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Black Holes and Hidden Dimensions

Slackware Geek writes "It is being reported in the Nature Science Update that a new observitory being built in Argentina to study cosmic rays could detect extra hidden dimensions if they exist. 'Cosmic rays could find holes in Standard Model of particle physics ...If the Universe contains invisible, extra dimensions, then cosmic rays that hit the atmosphere will produce tiny black holes. These black holes should be numerous enough for the observatory to detect.'"

200 comments

  1. Miniature Black Hole by alfredw · · Score: 4, Interesting

    Does anyone know how this works? Is this detecting the Hawking radiation from an evaporating hole, or is it detecting other effects?

    --
    In Soviet Russia, sig types you!
    1. Re:Miniature Black Hole by spiro_killglance · · Score: 4, Informative

      Yes they would be detected by the shower of particles produced by the (very rapid) Hawking radiation decay of the black holes. Its in the article except they didn't mention Hawking radiation by name.

    2. Re:Miniature Black Hole by mreece · · Score: 5, Informative

      >Is this detecting the Hawking radiation from an
      >evaporating hole, or is it detecting other effects?

      Yes, this is essentially what happens. The decay is actually somewhat more complicated; there is an initial "balding" phase in which the black hole loses its hair, along with a "spin-down" phase... after this, there's a very quick evaporation with high sphericity. Go to http://arxiv.org and search for "black hole production"; some recent papers by Giddings have details. It was believed for a while that the cross-section is geometric, which would lead to a good chance of detecting these in the next generation of colliders if large extra dimension (LED) models are correct. A paper by Voloshin indicates, on the other hand, that the cross-section is really exponentially suppressed by the black hole action. I'm not sure this has quite been settled completely.

      The basic idea behind all this, by the way, is that there may be extra dimensions which are large compared to the Planck scale (up to a millimeter in size - that's about as far as gravity has been probed!). Gravity would be a field in "the bulk", that is it propagates in all the dimensions, but the standard model fields are localized on some sort of 4-dimensional "brane." There are actually a couple of different models with large extra dimensions - one is the ADD model (Arkani-Hamed, Dimopolous, Dvali) and another is the Randall-Sundrum or "warped extra dimension" model. Searching on arxiv.org for any of these names should get you links to the papers.

      The basic reason for looking into all of this is the hierarchy problem, namely that the gravitational force is far weaker than the other forces. The electroweak scale is on the order of one TeV (= trillion electron volts, where one electron volt is about 1.6*10^-19 Joules). Gravity, on the other hand, is associated with a much higher energy scale. To explain this, the ADD model proposed that maybe the fundamental Planck scale is actually on the order of a TeV, like the electroweak scale. In other words, they solve the hierarchy problem by saying there is no hierarchy. Gravity propagates in more dimensions, so that its effect in our four-dimensional part of the universe looks much weaker. The other fields are localized in such a way that this ratio doesn't take any effect for them, so we see them at the "true" Planck scale on the order of a TeV.

      It just so happens that the TeV scale is what we're looking at with current colliders, which is why there's so much interest in this lately. But cosmic rays give an alternate approach. Keep in mind that these ideas are very speculative, but still worth looking into.

      --
      Matt Reece
    3. Re:Miniature Black Hole by Anonymous Coward · · Score: 0

      whoa, easy there...you could have gotten +5 just from the first paragraph. Then reply with "oh, and I forgot to mention....[2nd paragraph]". After some time passes, add, "I see I wasn't being clear enough. [3rd paragraph]". Then, for no reason, reply to whoever your first replier is who's at +4, and put, in parenthesese, your fourth paragraph. Oh, and forget your +1 bonus. Net result? Instead of 3 extra Karma, you get 16! Gawd, I miss the days before Da K-Kap.

    4. Re:Miniature Black Hole by MadAhab · · Score: 2
      The basic idea behind all this, by the way, is that there may be extra dimensions which are large compared to the Planck scale (up to a millimeter in size - that's about as far as gravity has been probed!).

      I find that amazing! Now if the theories allowed for those extra dimensions to periodically grow to sizes large enough to swallow single socks and small toy cars, I'd call it a very significant development.

      Seriously, I'm amazed that gravity hasn't been experimented with on smaller scales. Would that be something that requires zero-g and objects in a vacuum, or do you get other problems, like electrostatic/electromagnetic forces or even gravity of surrounding objects on those scales that make gravity difficult to measure directly at that resolution?

      --
      Expanding a vast wasteland since 1996.
    5. Re:Miniature Black Hole by Anonymous Coward · · Score: 0

      Yes, it's difficult to measure gravity on small scales, because to get two masses very close to each other, the masses have to be small, so the force is weak and hard to measure.

    6. Re:Miniature Black Hole by mreece · · Score: 2

      >Seriously, I'm amazed that gravity hasn't been
      >experimented with on smaller scales. Would that be
      >something that requires zero-g and objects in a
      >vacuum, or do you get other problems, like
      >electrostatic/electromagnetic forces or even
      >gravity of surrounding objects on those scales that
      >make gravity difficult to measure directly at that
      >resolution?

      Apparently the current limit is now somewhat less than a millimeter, but still on the order of a millimeter. Yes, it is very difficult to test. A group at the University of Washington has developed small-scale gravity tests; see http://www.npl.washington.edu/eotwash/shortr.html for an explanation.

      Basically, you have the right idea; it's hard to screen out all of the other effects at a scale that small, which is why studies at the millimeter scale are extremely difficult.

      --
      Matt Reece
    7. Re:Miniature Black Hole by ShoeHead · · Score: 1

      Alright, if I hadn't just noticed that this guy's from Uchicago, I probably would be saying that this guy's post is a sham. As it stands, I'm still too lazy to look all this stuff up to confirm it.

      UChicago is a good university for astrophysics, but I applied (this year) wanting to major in physics. They've got a second to Caltech teacher:student ratio, and a fairly good acceptance rate.

    8. Re:Miniature Black Hole by outrider45 · · Score: 1

      There are miniature black holes... they're called point singlarities. They have a shwartschild radius ( a few centimeters ) and have the enertial mass of a small planet, approx. 0.4g's. It may be just me, but if you could generate these and fire them at a decent percent of the speed of light you'd have one killer weapon.

      --
      'I am a mystery, wrapped in an enigma, and smothered with secret sauce' -Jimmy James, News Radio, 1996
    9. Re:Miniature Black Hole by adlam.bor · · Score: 1

      simple, lube up your younger brother, then begin fucking his ass. you may need to tie him down to guarantee that he doesnt fight back, as you will have to get a few friends together to fuck his tiny little ass for a few days straight. at the end of this buggery, shove an entire vacuum cleaner into his gaping anus, then turn it on. then be sure to place a large object into the opening on this gaping asshole, when the pressure builds up to the point of sucking the large object in, the universe will the collapse into your younger brothers rectal cavity. at that point, you have created a black hole.

      if it doesnt work, keep trying until it does, youll get it eventually...

  2. Must resist... by imrdkl · · Score: 4, Funny
    Black holes, expensive science project, currency devaluation, it's got potential, yes? Anyways, a different dimension would at least give them a new place to search for a president...

    Moderators, punish me now.

    1. Re:Must resist... by Anonymous Coward · · Score: 0

      Here about that pretzel incident?

      I don't mean to be rude or anything, but if the man can't remember which one to do, chew or swallow, first then there must be a problem.

    2. Re:Must resist... by notfancy · · Score: 0

      Black holes, expensive science project, currency devaluation, it's got potential, yes?

      Let me tell you, from this side of the black hole it sounds more surreal than eleven-dimensional spacetime.

      Maybe we're all radiating slowly away...

    3. Re:Must resist... by Anonymous Coward · · Score: 0

      the hidden dimension must be where all my lost socks and lost files went.

    4. Re:Must resist... by Anonymous Coward · · Score: 0

      I think he choked on an old gob of cocaine left over from his "young and irresponsible" days, when his rich/powerful family covered up his cocaine traficking arrest.

    5. Re:Must resist... by barawn · · Score: 3, Insightful

      I do just want to clear things up -

      Argentina didn't come up with this science project - the world did. It's an international collaboration of dozens of countries and about 300 scientists worldwide. Argentina was chosen as the southern site of the array due to the location - the array consists of a flourescence detector, which requires stable weather and clear air. The northern site is still under discussion, though it seems most likely to be in Utah (along with the dozen or so other cosmic ray observatories in Utah).

      The Auger collaboration is then completely distinct from Argentina's government, so we don't really worry about the governmental problems except for the problems they cause our friends down there and the Argentine portion of the collaboration.

    6. Re:Must resist... by sharkey · · Score: 2

      Anyways, a different dimension would at least give them a new place to search for a president...

      Ahhh. Hopefully, it'll be a pretzel-proof dimension.

      --

      --
      "Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
    7. Re:Must resist... by JabberWokky · · Score: 2
      Ahhh. Hopefully, it'll be a pretzel-proof dimension.

      No, that's American presidents. They'd be better off looking for a dimension full of spanish speaking Alan Greenspan clones willing to run.

      (Note to anybody who takes that wrong - America had Herbert Hoover for their financially inept leader, and in comparison Clinton *and* Bush look good, either choking on a pretzel or choking an intern with his...)

      --
      Evan

      --
      "$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
    8. Re:Must resist... by sharkey · · Score: 2

      ...America had Herbert Hoover for their financially inept leader...

      Better than J. Edgar Hoover. At least Herbert wore men's clothes, AFAIK.

      --

      --
      "Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
    9. Re:Must resist... by schon · · Score: 1

      the hidden dimension must be where all my lost socks and lost files went.

      Well DUH..

      I thought everyone knew this! The dissolution of the soap particles in the washer, combined with centrifugal action, friction and heat of the dryer can open a temporary wormhole, that is just small enough for socks and underwear to fit through..

      Jeeze, this is elementary physics, people!

    10. Re:Must resist... by drik00 · · Score: 1

      You Brits are so funny...you jump on us when we have something funny happen with our Presidents, but you forget that the whole world views your Royal family as a joke. Something about "people in glass houses..."?

      --
      Beer, now there's a temporary solution -- Homer Jay S.
    11. Re:Must resist... by Anonymous Coward · · Score: 0

      View the royal family as a joke? Hell No!!! We could learn a great deal from them. Just look at the queen. Wouldn't you like to know her secret for living to be 237 years old? And to think, she doesn't look a day over 160.

      And let's not forget Diana. Her transformation from normal person to wealthy international celebrity, accomplished by simply being the skankiest whore she could be, is a virtual blueprint to fame and fortune for young women all over the world.

  3. Bad idea? by Sc00ter · · Score: 0, Troll
    Why does this sound like a bad idea? And if it's not, could somebody please explain why it's not? Creating all these black holes and stuff seems dangerous.

    1. Re:Bad idea? by JanneM · · Score: 0, Redundant

      The experiment doesn't create black holes; it's just about detecting whether cosmic rays produce them naturally.

      If they do, BTW, the holes are so small that they evaporate almost instantly.

      /Janne

      --
      Trust the Computer. The Computer is your friend.
    2. Re:Bad idea? by RareHeintz · · Score: 3, Informative
      OK, that was probably a troll, but I'll bite...

      Nobody's talking about creating any more black holes than get created naturally. They are talking about detecting black holes that do get created naturally in our upper atmosphere.

      If you actually need more explanation, go to the article.

      OK,
      - B

    3. Re:Bad idea? by mandolin · · Score: 0, Redundant
      Creating all these black holes and stuff seems dangerous.

      According to the liner notes, the observatory would detect black holes, not create them.

    4. Re:Bad idea? by Anonymous Coward · · Score: 0

      Because the black holes don't last long enough to suck anything up. It was mentioned in the article that they evaporated very quickly, due to Hawking radiation.

  4. antimatter particles by Anonymous Coward · · Score: 0

    if a black hole sucks in an antimatter particle, but does not suck in a matter particle, what happens?

    1. Re:antimatter particles by hogsback · · Score: 1

      This is called Hawking radiation.

    2. Re:antimatter particles by nusuth · · Score: 5, Informative
      nope, hawking radiation is when a spontnous pair creation occurs, but one of the members of pair falls into the black hole while the other escapes.

      Reply to parent: nothing. antimatter is not a very exotic thing, normal matter with reverse charge reverse spin. Once in the blackhole there is no telling whether what fell was matter or antimatter, they all behave the same (increase black hole's mass, that is, and nothing else.)

      --

      Gentlemen, you can't fight in here, this is the War Room!

    3. Re:antimatter particles by Tattva · · Score: 1
      So is there a tendency for the anti- or real matter of the pair to fall in the hole? If it is balanced then Hawking radiation doesn't affect the size of the hole, but if antimatter does tend to fall into the hole and the real matter tends to escape, then the antimatter particle would vaporize some matter in the black hole and the tendency for the Hawking radiation would be to evaporate the black hole, no?

      --
      personal attacks hurt, especially when deserved
    4. Re:antimatter particles by Anonymous Coward · · Score: 0

      Yes, that's what Hawking radiation is, and that's what the person was talking about. In spontaneous pair creation, one particle is an antiparticle. That's why they are so short-lived. They tend to annihilate each other immediately. But it really doesn't matter if the matter particle or the antimatter particle falls into the gravity well. Either one will do the same job. And another way of thinking of antimatter is that it's time-reversed matter. Symmetry is fun.

    5. Re:antimatter particles by mreece · · Score: 2

      >antimatter is not a very exotic thing, normal
      >matter with reverse charge reverse spin. Once in
      >the blackhole there is no telling whether what fell
      >was matter or antimatter, they all behave the same
      >(increase black hole's mass, that is, and nothing
      >else.)

      Sorry for being so pedantic, but they also affect its charge and angular momentum. So you're essentially right, except that if you know, for instance, that either an electron or positron fell into a black hole, and you could somehow monitor its charge, you could distinguish which.

      --
      Matt Reece
    6. Re:antimatter particles by nusuth · · Score: 2, Informative
      No, both can fall equally likely. You can feed a blackhole with either matter or antimatter and the hole wouldn't care, it will just grow. It will also attract both with equal probabilities.

      How hawking radiation actaully occurs is something I understand but do not grok. I can't really explain from ground up, since I'm not an expert. I'll give it a try but don't quote me on this.

      The whole process is lending a bit of energy from nothing, such that it won't violate conservation of energy by being strictly in limits of uncertanity part of uncertainity principle. Sometimes this energy is borrowed in form of two photons with opposite momentum, some times a particle-antiparticle pair. You have to pay back soon what you have borrowed, but sometimes the blackhole gets greedy and swallows either one of your photons or you particles. When the death calles for destruction, black hole no option but to pay back what debt it has inherited. So far, so good. Now here is the part I don't really understand (I can explain preceeding part in techincal terms and in detail if you prefer, but not this part) but accept: black hole for some reason pays the debt for the pair, not only the one it has assimilated. If it does this, the other particle, photon, whatever is free to roam the universe.

      --

      Gentlemen, you can't fight in here, this is the War Room!

    7. Re:antimatter particles by nusuth · · Score: 1
      So you're essentially right, except that if you know, for instance, that either an electron or positron fell into a black hole, and you could somehow monitor its charge, you could distinguish which.

      These are two thing I (as a chemical engineer) "know" about black holes which conflicts with each other. I have always wondered this, which one is correct so thanks for giving me a chance to ask:

      1 - If a charged particle drops into a black hole it has to change black hole's chargebecause of conservation.

      2 - It also happens to be the case that no information can be obtained from (if you excuse the term) "inside of" event horizon, we can determine mass changes and angular momentum changes because it changes the shape and size of event horizon. If something happens to the black hole that doesn't change the properties of its detectable "border", event horizon, we aren't supposed to be able to detect that.

      So how can charge be preserved if it doesn't affect event horizons properties? How can you tell total charge of a black hole?

      --

      Gentlemen, you can't fight in here, this is the War Room!

    8. Re:antimatter particles by barawn · · Score: 4, Interesting

      You're right - they don't jive.

      So, to explain: black holes have three properties. They're the universe's most massive particles in that respect. :) A black hole is completely described by its charge, mass, and angular momentum. It has no other properties (hence "black holes have no hair" - "hair" in this case is any other property).

      Charge does affect the event horizon's properties, basically in the same way that angular momentum does - it alters it massively. You can get very weird black holes, including ring singularities instead of point singularities (black hole donuts!).

      In reality, it's very difficult to charge up a black hole. Most of the matter falling in is neutral, and a buildup of one charge will result in a preferential draw of the other charge (opposites attract, y'know) and therefore, an overall neutral black hole. In falls an electron, and a proton is drawn preferentially over another electron. You also need a ton of charge to change the event horizon significantly - but in theory, it is possible to tell.

    9. Re:antimatter particles by mreece · · Score: 2

      >1 - If a charged particle drops into a black hole
      >it has to change black hole's chargebecause of
      >conservation.

      This is correct - charge, momentum, and angular momentum are all globally conserved, so far as we can tell.

      Note that "mass" is not *really* conserved - this is especially obvious in certain decays of elementary particles (i.e., electron+positron -> photon+photon; you end up with 0 mass). What *is* conserved is the energy-momentum four-vector (E, p), and for any one particle E^2 - p^2 = m^2. Mass only is conserved in the nonrelativistic limit. But I digress...

      >2 - It also happens to be the case that no
      >information can be obtained from (if you excuse
      >the term) "inside of" event horizon,

      This is basically true: no information is obtained. It is said that "black holes have no hair." But they do have a few properties - charge, mass, and angular momentum are essentially it. (Temperature and entropy also, but these depend on mass.)

      >determine mass changes and angular momentum
      >changes because it changes the shape and size of
      >event horizon.

      This is somewhat true; I'm not sure I would have expressed it in terms of "shape and size." I have to admit my knowledge of the black hole solutions in general relativity is fairly rudimentary, so I'm not sure in exactly what way that is true, but I think it is. There is a metric - called the "Kerr black hole" - that describes black hole solutions that spin; I think when they have charge there is another term. But the thing to note is that the metric of spacetime is actually different for different values of black hole spin, or charge. You'll also see a change in the electromagnetic potential (phi, A) outside the black hole for the charged case. So there are external effects.

      >So how can charge be preserved if it doesn't
      >affect event horizons properties? How can you
      >tell total charge of a black hole?

      The simple answer is: Maxwell's equations. Anything with charge, even a black hole, will change your electromagnetic potentials.

      In other words, black holes tend to wear their charge, angular momentum, and mass "on the outside", in some sense.

      --
      Matt Reece
    10. Re:antimatter particles by barawn · · Score: 4, Informative

      It's mainly shape of the horizon and shape of the singularity that's affected due to charge/angular momentum. That, and the stability relation - too much charge/angular momentum, and everything goes to hell in a handbasket. If I had my copy of Misner, Thorn, and Wheeler here, I could expound a bit, but...

      Schwarzschild metric: mass only
      Kerr metric: mass+angular momentum
      Reissner-Nordstrom metric: mass+charge
      Kerr-Newman(sp? on second): mass+charge+angular momentum - i.e., real black holes.

      J messes with the angular dependence and structure of the horizon. Not sure what charge does - it doesn't enter into the metric in many places other than the numerator. You'll note that a != 0 causes the metric to be nonsingular at the origin...

      Charged/spinning black holes are interesting, because the Schwarzschild throat/Einstein-Rosen bridge may be passable in some geometries. For a standard Schwarzschild geometry, it's not - try to pass through the center of a nonspinning noncharged black hole, and you'll die, as it's not stable.

    11. Re:antimatter particles by dragons_flight · · Score: 3, Informative

      Electric field comes out of the event horizon. Actually it's more correct to say that electric field is created at the event horizon, since it doesn't make any sense to say that it propogates up out of the horizon. It is perfectly valid to say that the electric field lines have been frozen into the event horizon, and are a property of the event horizon. As charged particles cross the horizon they contribute new electric field which is measurable by the way it distorts and adds to the existing field lines.

      Net charge is a property we could infer from the electric field, but the actual field emanates from the event horizon, not the unreachable singularity.

    12. Re:antimatter particles by Anonymous Coward · · Score: 0

      if antimatter is time-reversed matter, then why would it be the opposite charge of its corresponding matter particle? Does time actually have something to do with charge? I don't see how since we have both charges in positive time, in both matter and antimatter.

    13. Re:antimatter particles by julesh · · Score: 1

      To be honest, I wouldn't expect to survive passing through the center of a black hole, even if it held a charge equivalent to half the electrons in the universe, and was spinning so quickly that its mass only just held it together, but maybe that's just me...

    14. Re:antimatter particles by barawn · · Score: 2

      You'd think so, wouldn't you? But it isn't hard to calculate the tidal stresses on particles with world-lines passing through the throat region (it's just differential acceleration, after all). I know nothing can pass through a Schwarzschild throat, but that's not true of a Kerr metric. Of course, that's assuming that the throat opens up in another location of the universe and that it's not behind a horizon there, but hey.

    15. Re:antimatter particles by ShavenYak · · Score: 1

      if antimatter is time-reversed matter, then why would it be the opposite charge of its corresponding matter particle?

      Think about how you would tell whether a charge is positive or negative - its movement through a magnetic field. Now imagine seeing a film of it run backward. You would make the opposite determination about its charge. Incidentally, you would also notice that it has an opposite spin.

      You can even look at matter-antimatter annihilation this way: A matter particle is traveling forward in time, becomes somehow 'unstable', turns backward through time, and emits two photons to satisfy mass-energy conservation in the future. It's new backward path through time is seen by outside observers as a separate antiparticle which collided with the first particle to produce the photons.

      --

      Hey kids, there's only 5 days left 'til Yak Shaving Day!
    16. Re:antimatter particles by esonik · · Score: 1

      but if antimatter does tend to fall into the hole and the real matter tends to escape, then the antimatter particle would vaporize some matter in the black hole and the tendency for the Hawking radiation would be to evaporate the black hole, no?

      No, once matter or anti-matter has passed the event-horizon, nothing can come back - not even the pair annihilation radiation. Hawking radiation occurs at the border of the event horizon, where it is just possible for the radiation/particle to escape. Pair annihilation inside the black hole also doesn't affect it's apparent mass to the outside observer, because the annihilation radiation itself also "generates" gravity (as does every from of energy).

      The reason why Hawking radiation reduces the mass of a black hole is that the energy for the pair production at the event horizon is taken from the black hole, but one partner of the pair manages to escape (otherwise it's not called Hawking radiation) thereby reducing the mass/energy of the black hole.

  5. `Width' of a single atom by joebp · · Score: 2, Interesting
    Many physicists now argue we cannot experience these extra dimensions directly because they became rolled up more tightly than the width of a single atom during the Big Bang.
    Wow, how scientific.

    There's more information about the Pierre Auger Project here.

    1. Re:`Width' of a single atom by joib · · Score: 1

      Do you have a problem with the concept of 'width of a single atom' or what are you saying? Or perhaps radius would be a better word? Of course, the radius of an atom is not something which is very precisely defined due to quantum mechanics. IIRC, a common definition of the radius of an atom is the value r for which (formula in LaTex) \int ^{r}_{0}dr\int d\Omega \Psi ^{\dagger }\Psi >0.5 where \Psi is the normalized wavefunction for the atom. Of course, determining \Psi for anything more complicated than a He atom is a many-body problem with no analytical solution (supercomputers here we come!).

    2. Re:`Width' of a single atom by joib · · Score: 1

      Uh oh... To correct myself, the He atom is no longer analytically solvable, only the H atom is. Of course depending on whether you are calculating electron orbitals or the nuclear structure. I.e. for electron structure, a proton with only one electron orbiting it, and if you're calculating nuclear structure the deuteron nucleus (1 proton + 1 neutron) are the most complicated things with analytical solutions. The rest is more or less daring approximations, and number crunching...:)

    3. Re:`Width' of a single atom by joebp · · Score: 1
      the radius of an atom is not something which is very precisely defined due to quantum mechanics
      Indeed. What I was trying (unsuccessfully I must admit) to communicate is that relating something to the size of an atom is like measuring my head with an elastic ruler, for the reasons you give.
    4. Re:`Width' of a single atom by Decimal · · Score: 1, Flamebait

      > any physicists now argue we cannot experience these extra dimensions directly because they became rolled up more tightly than the width of a single atom during the Big Bang.

      Do you have a problem with the concept of 'width of a single atom' or what are you saying? Or perhaps radius would be a better word?

      Width or radius, neither would matter. "During" the big bang (0 - 5 seconds for example), there were no atoms. The universe was far too hot for any to form.

      --

      Remember "Bring 'em on"? *sigh
    5. Re:`Width' of a single atom by Anonymous Coward · · Score: 0

      You can experimentally measure form factor & fourier transform to give charge distribution.

    6. Re:`Width' of a single atom by barawn · · Score: 2

      Actually, as I've stated elsewhere, the best information on the PAO is here, because this is the Argentine site, where we're actually doing things. Most of the stuff on auger.org is administrative and outreach stuff - if you want to find out what's actually going on, check out the Argentine page. If you notice, it's actually rather active! (Check under the CDAS page for a better list of the milestones we've reached).

    7. Re:`Width' of a single atom by Anonymous Coward · · Score: 0

      same thing goes for the size of anything then. All rulers are after all, elastic.

      At least that's my entry in this pedantry competition, what do I win?
      And as for 'How unscientific', scientists use rule of thumb, or orders of magnitude estimations in their arguments all the time, in the real world, away from classroom toy problems.

  6. Re:Hey morons! by jfroot · · Score: 0, Offtopic

    What is even more disturbing than this is the fact that someone had to sit and look at the goatse.cx picture long enough to make an accurate ASCII version.

  7. "Extra" by Anonymous Coward · · Score: 1, Interesting

    Extra is the wrong word; "undetected" or "hitherto unseen" is more accurate. Extra implies "laws of nature" and similar nonsense that the cult of science preaches to the guild.

    Any other dimensions that are there are already existing, and are not "extra" or in addition to whats in the universe.

    1. Re:"Extra" by Hunsvotti · · Score: 1

      "Undetected" or "hitherto unseen", I'll agree with. I do not get your reasoning for "extra" implying "laws of nature", nor do I see how science is a "cult."

  8. Not a bad idea by Anonymous Coward · · Score: 0

    If you care to read the article on Slashdot's frontpage, it clearly says:

    'Cosmic rays could find holes in Standard Model of particle physics ...If the Universe contains invisible, extra dimensions, then cosmic rays that hit the atmosphere will produce tiny black holes. These black holes should be numerous enough for the observatory to detect.'

    The observatory does not create black holes, it simply looks for ones that occur naturally in the atmosphere.

  9. Black holes... by prof187 · · Score: 1

    Black holes are weird things. I mean, think about it, something that is strong enough that light can't even get out of it. And like it warps space. That's deep...

    --

    My other sig is an import.
    1. Re:Black holes... by PhuCknuT · · Score: 1

      Yes but if you accept the fact (fairly well proven) that all matter warps space, then black holes aren't all that strange anymore. If everything warps, space, then it becomes fairly obvious that something dense enough will warp it to the point that it's inescapable.

    2. Re:Black holes... by batboy78 · · Score: 1

      Deep indeed, but black holes aren't the only celestial bodies that affect light, any large star or planet can bend light toward it. Thus making stars appear in different regions of the sky then they actually are.

    3. Re:Black holes... by Genyin · · Score: 1

      Black holes suck.

  10. Never expected to read that story by Deosyne · · Score: 1

    Every time I read kooky sounding things like this, I want to shake my head and sigh, but then I think that is probably what a crapload of people were doing when Goddard was sitting around playing with frames and fuel and just feel that weird, "Damn, they could actually be on to something," feeling. I'm just waiting for some religious scholar to do something similar so I can be the first man to fly into the sun and have bragging rights in the afterlife for most badass exit.

  11. circular/spherical space-time by carambola5 · · Score: 5, Insightful

    I wonder if this can shed some light on the subject. It talks about modeling a universe where light naturally travels at a fixed radius rather than a straight line. Assuming the radius to be extremely large, the proposed universe would act quite similarly to ours. Assuming an extremely small radius (small as in atomic-level) and I think we may be hitting upon the door of the next dimensions.
    Think of it... In a world where light traveled in a fixed radius of one meter, you would see the back of your head if nothing is in the way. And, it would seem, that your head is 6.28 meters away from you. Problem is, you wouldn't be able to see beyond that one-meter radius circle. Now, what if that radius was shrunk to the atomic level... you wouldn't be able to see beyond the circle(sphere?) that the fixed radius spans. Obviously, your eye is way too large to detect that kind of precision.
    Thoughts anyone?

    --
    IWARS.
    People, in general, disappoint me. Politicians even more so.
    1. Re:circular/spherical space-time by bunratty · · Score: 1

      It's just a hypothetical "universe" for use in a mathematics class, and someone wrote ray-tracing software to determine what vision would be like in that universe. I don't see that having any bearing on physics in this universe!

      --
      What a fool believes, he sees, no wise man has the power to reason away.
    2. Re:circular/spherical space-time by Tattva · · Score: 1
      This sounds like it is something different from the debate on whether the universe is open, closed, or balanced. IIRC, that debate has to do with whether parallel lines tend to converge, diverge, or remain the same "distance" apart over the distance of the galaxy. There is a good argument that the universe is exactly balanced, because if it is closed or open the equations lead quickly to massive expansion or sudden collapse. Or am I wrong? :)

      --
      personal attacks hurt, especially when deserved
    3. Re:circular/spherical space-time by carambola5 · · Score: 3, Informative

      First of all, it's believed that these other dimensions are so-called "curled up," meaning that there is some sort of circular attribute to them. Taking this into account, I remembered viewing that website and put some ideas together:

      Think of what the author said in terms of particle physics. He/She looked into a world where photons moved in a circular fashion. If the radius was big, it'd be just like our current universe. If it was small, we wouldn't be able to see much beyond our point of view.

      What I'm trying to say is that photons move in the three orthonormal dimensions, and change coordinates with respect to the fourth dimension. Duh. Everyone knows that. But what if there were some other particles (Higgs boson, perhaps?) that function similarly, only on these "curled-up" dimensions? The reference to the website was made simply to introduce the reader to a circular/spherical coordinate system. My comments following the link asked the reader to reduce the radius of said coordinate system.

      --
      IWARS.
      People, in general, disappoint me. Politicians even more so.
    4. Re:circular/spherical space-time by slashdot2.2sucks · · Score: 1

      "if it is closed or open the equations lead quickly to massive expansion or sudden collapse."

      On the universal time scale, what is 'sudden'

      Last I heard, and I haven't payed attention in about 2 years, evidence was suggesting that Hubble's constant was getting larger over time ... the universe is expanding faster and faster

    5. Re:circular/spherical space-time by jaoswald · · Score: 2

      I'm no expert, but my best guess for "sudden" is the Planck time (derived from G, Planck's constant, and the speed of light) which is 5 x 10^-44 seconds.

      The only other possibility I could imagine is the size of the universe divided by the speed of light, which is something like the age of the universe. That of course, would have been sudden when the universe was celebrating it's Planck's time birthday, but pretty darn sluggish today.

    6. Re:circular/spherical space-time by Anonymous Coward · · Score: 0

      go read "redshift rendevous"

    7. Re:circular/spherical space-time by slashdot2.2sucks · · Score: 1

      It was a rhetorical question.

      I appologize for being a smart ass, I should have just said no.

    8. Re:circular/spherical space-time by Richard+Kirk · · Score: 1
      Yup, you got it. If you have a circular dimension, then you can stick standing waves into it. You could have a clockwise wave with N periods to the universe, and an anticlockwise wave with N periods to the universe. This would mean a wavefunction could have a set of two possible energy conditions for each integer N above zero. See under Kaluza-Klein theory (yeah, a bunch of old guys got there first, tough bananas eh?).

    9. Re:circular/spherical space-time by ThePixel · · Score: 3, Funny

      If it was small, we wouldn't be able to see much beyond our point of view.

      Correct me if I'm wrong... we can't see beyond our point of view now. That's why it's a point of view.

      --
      People see the world as they are, not as it is.
  12. Correction by Anonymous Coward · · Score: 0

    Sorry, that should be "hear" instead of "here".

  13. Interesting theory, but practice? by oliverk · · Score: 1

    Let's assume for a moment that the observatory really IS able to discern the energy released as the minature black holes--wouldn't that energy be largely comprised of particles from our own spacetime dimension? My assumption is that the energy released would be the collision of the singularity with the surrounding particles, so in effect all we would be able to track would be "common" energy, not the extradimensional black hole which would have collapsed into nothingness.

    Maybe I'm missing something...

    --
    ---- Please be nice in case my Slashdot karma ~= my real life karma.
    1. Re:Interesting theory, but practice? by bunratty · · Score: 1

      Very tiny black holes evaporate very quickly due to Hawking radition. The radiation is actually the black hole itself exploding.

      --
      What a fool believes, he sees, no wise man has the power to reason away.
    2. Re:Interesting theory, but practice? by Anonymous Coward · · Score: 0

      No, that energy wouldn't "largely" be comprised of particles from our own spacetime dimension, it would COMPLETELY be comprised of that. We aren't talking about walking through a dimensional doorway here, into a realm of science fiction. Your assumption is wrong, the energy in question is Hawking radiation, which has nothing to do with the singularity. The cosmic censorship principle forbids the singularity from being able to collide or act upon anything outside the black hole. I don't know what kind of energy you expect to find other than "common" energy, but I recommend you brush up on your physics and maybe read something on string theory, like Brian Greene's "The Elegant Universe".

    3. Re:Interesting theory, but practice? by Cato+the+Elder · · Score: 2

      It's not that the energy would be from particles from higher dimensions, but rather that without the extra dimensions the cosmic rays would have insufficent energy to form the black holes in the first place. This is made pretty clear by even a cursory reading of the article, but that seems to doesn't seem to be the norm around here.

      Now, a slightly more interesting question is why the extra dimensions would lower the threshold of singularity formation. Do they make space more compressible by giving it more room to flex in or what?

    4. Re:Interesting theory, but practice? by Anonymous Coward · · Score: 0

      I think that maybe the rest of the replies to this have missed the point. The reason that they would feel comfortable saying that they detected a black hole is because they have already done the calculations/monte carlo simulations of the event (the black hole evaporation) and seen that it would produce a shower of particles that probably decay very quickly into other particles, and so on a few times until there is nothing but a shower of yes, completely "ordinary" (my quotes) particles that actually pass through their detector. The idea is that they can look at the pattern of those particles they detected and more or less extrapolate backwards to the original event that caused them, which with a certain likelihood would be black hole evaporation. This is how all experimental particle physics is done, nothing is actually detected directly, but the after-effects are tell-tale streams of particles we know and love going in certain directions that would be pretty unlikely otherwise. That's why there is always some imprecision in the rarer types of events, e.g. observation of the top quark. They weren't able to peg it's mass to something more than like 180 MeV +- 10 MeV initially (maybe it's GeV, it's been a while since I took the damn class, and I am too lazy to look it up). So they model the event to tell them what the after effects will look like (if their theory is right that is) and how often they should expect it and then they sift through the data looking for the signature of the event. So essentially, they know what they think should happen according to string theory or whatever, and they will look for the tell-tale signs of it. I assume it has a pretty distinctive signature, or they probably wouldn't be publishing it in physical review letters. Anyway, I hope that helps, and if it doesn't, sorry.

  14. Could help in validating string theory? by Anonymous Coward · · Score: 1, Insightful

    If I remember correctly, the idea that our universe contains extra tiny dimenions is a key component of string theory. If these hidden dimensions can be proven to exist, then this could lend string theory a lot of credibility.

  15. Of course there are! by Graff · · Score: 2, Funny

    Of course there are extra, invisible dimensions! Where else do you think all those socks go when you wash them in the laundry?

    1. Re:Of course there are! by AstroJetson · · Score: 0

      Where else do you think all those socks go when you wash them in the laundry?

      My navel...in the form of belly-button lint.

      --
      Admit nothing, deny everything and make counter-accusations.
    2. Re:Of course there are! by Graff · · Score: 0

      Hmm, what if you took that belly-button lint, knitted a pair of socks from it, and washed them in the laundry. Would you set up some sort of odd sock-belly-button lint matter feed-back loop? Inquiring minds want to know!

      I smell an experiment brewing here, or maybe that's just April Fresh Downy I'm smelling...

    3. Re:Of course there are! by AstroJetson · · Score: 1

      I do think you're on to something. Starting tonight, I shall begin collecting my belly-button lint in a quart Mason jar and when I have enough (about 2 years from now), I'll get my grandmother to knit me a pair of socks from it. Then it will be OUR experiment on the front page of /. not some lame-ass story about some stooopid black hole observatory.

      --
      Admit nothing, deny everything and make counter-accusations.
    4. Re:Of course there are! by tRoll+with+Butter · · Score: 1
      Of course there are extra, invisible dimensions! Where else do you think all those socks go when you wash them in the laundry?

      It has something to do with static electricity. It is interesting to note that while man has found a way to artificially create this phenomenon with a major appliance, dogs are able to do it on their own. Dave Barry wrote a great article about this a few years ago. To quote:

      Darrell's theory is that ''the dirt is being pawed into the ozone layer,'' or that ''enough dirt is being tossed into the sky that another planet will be formed somewhere between Earth and Mars.'' Thanks to the Hubble astronomers, we now know that this is not the case; a more logical explanation is that dogs have somehow figured out how to paw the dirt into (speaking of Newt Gingrich) a completely different dimension.
      --

      ---
      Siggy, siggy, siggy, can't you see? Sometimes your puns just irritate me.
    5. Re:Of course there are! by Anonymous Coward · · Score: 0

      They become coat hangers and easter grass.

  16. Experimental proof for string theory by bravehamster · · Score: 5, Informative

    This would be a nice feather in the cap of string theory, which to this point does not have any experimental observations to back it up.

    One of the predictions (or you could say requirements) of string theory, is that the universe contains a total of 11 space-time dimensions, 7 of which are "curled-up" and are extremely tiny. Every time you move, you pass through the entire universe in each of these 7 dimensions, although your position in the 3 "enlarged" dimensions hardly changes. The interesting thing is that a guy predicted these extra dimensions way back in the 1910's, and was ignored for about 50 years. Experimental evidence on the side of string theory (or as they're calling it now, M-theory) would go a long way towards convincing the experimental physicists that all these theoretical physicists aren't off their rockers.

    --
    ---- El diablo esta en mis pantalones! Mire, mire!
    1. Re:Experimental proof for string theory by killthiskid · · Score: 2

      Actually, String theory has moved to M-theory, and involves "super strings" and membranes. I've read many books on the subject... most of them have taken a long time to read, i.e. read a few pages, think about it for a few days, go back...

      Anyhow, some links:

      My take is that, as has been said before, the world consists of 11 dimensions. There are actually many super-string/m-theories, but they are not contradictory, kinda like different views of the same thing.

      A main problem with these theories is that there are many (infinite?) solutions the math sets that descibe them.

      A 'string' in the theory is like a circular guitar string that is taunt... it has certain modes of vibration, each mode representing a certain type of particle.

      Also, there are different types of strings... strings that are self connecting, open string, string that loop around more than once...

      Ok, that probably didn't clear anything up...

    2. Re:Experimental proof for string theory by wpmegee · · Score: 2, Interesting
      Or, we could just build a superconducting particle accelerator as large as the solar system. Then we could probe distances as small as the Planck length (the approximate size of most strings).

      Then again, with the SSC canceled, maybe not . . .

    3. Re:Experimental proof for string theory by Anonymous Coward · · Score: 1, Insightful

      Extra dimensions weren't predicted back in the 1910's. They were postulated back in the 1920's, by Kaluza and refined by Klein. Kaluza-Klein theory was not ignored; IIRC, Einstein helped Kaluza get a faculty position on the basis of this work. K-K theory had problems though (e.g., the existence of the extra unobserved dilaton field). It got resurrected in the context of grand unified theories, until Witten killed it by showing you couldn't get the Standard Model out of it. (Then he shot down his own proof when working on M-theory, by introducing compactification onto a line segment rather than a closed manifold.)

    4. Re:Experimental proof for string theory by mreece · · Score: 3, Interesting

      Detection of signatures of large extra dimensions wouldn't actually offer direct experimental evidence for string theory. Yes, string theory predicts extra dimensions, but it isn't necessarily the only theory that does.

      Direct evidence for string theory at any point in the near future is highly doubtful. We just can't get good evidence of such high energy scales. We could see associated effects, like extra dimensions or supersymmetry, but those don't necessarily imply string theory.

      --
      Matt Reece
    5. Re:Experimental proof for string theory by Anonymous Coward · · Score: 0

      Of course the recent interest in these large extra dimension theories is to resolve the hierarchy problem. Since this places GUT scale at 1-10 TeV cosmic rays (and the LHC) would be able to probe GUT + produce black holes (according to semiclassical analysis).

      But Planck scale compactified extra dimensions, which are all you need for M theory, would not necessarily be detected by this means. This experiment is only really good for supporting/ruling out large extra dimensions and Randall-Sundrum universes. (But this is very worthwhile.)

    6. Re:Experimental proof for string theory by Anonymous Coward · · Score: 0

      go back to masturbating to the elegan tnuiverse, you twat

  17. What is the Evaporation Process Then? by Tattva · · Score: 1

    I've been trying to wrap my mind around the basic ideas of quantum physics with the help of one of those popularizing books, but they have not talked about black hole evaporation. Is this like alpha radiation, where the probability curve of the location of a couple of protons is such that there is a reasonable chance that it will find itself outside of the range of the strong nuclear force? (but in the case of the black hole the force would be gravity and the location would be the event horizon or at least the point where the electrical force pushing on an ion would be stronger than gravity.)

    --
    personal attacks hurt, especially when deserved
    1. Re:What is the Evaporation Process Then? by PhuCknuT · · Score: 1

      It's called Hawking radiation, it occurs when spontaneous pair generation occurs right next to the event horizon and one of the particles falls in while the other escapes.

    2. Re:What is the Evaporation Process Then? by japer · · Score: 1
      My ( basic ) understanding is that this is a quantum mechanical process. Right outside the
      event horizon you get particle-antiparticle
      creation. If memory serves the antiparticle is absorbed by the black hole ( reducing it's mass)
      and the particle is emitted.


      http://wwwusr.obspm.fr/admin/seminaire/chalonge/ bl ack-hole.html

    3. Re:What is the Evaporation Process Then? by dragons_flight · · Score: 2

      Yes. The process by which blackholes evaporate is called Hawking Radiation. One interpretation of the evaporation is that particles tunnel out of the gravity well by a quantum process exactly analogous to that attributed to spontaneous radioactive decay. Of course gravity isn't limited to a short distance, which decreases the probability of quantum tunnelling.

      An alternative interpretation (and the more popular one), is that virtual particles of positive and negative mass enegries are created near the event horizon, and the negative mass energy particles fall into the black hole, while the positive mass particles escape. Ordinarily such virtual particles are created all the time and quickly annhilate each other back out of existence, but in the rare case that one crosses the event horizon they can't come back together and thus one becomes a real particle. Since we assume that negative mass energies can never be truly realized, only positive particles will ever escape.

      In both cases the blackhole loses mass and appears to emit particles. In fact, there is nothing about Hawking radiation that makes either interpretation more valid than the other.

  18. It happens all the time! by DaftShadow · · Score: 4, Informative
    Well, sort of :)

    As the article said higher up, the smashing of cosmic rays into ozone has been known to create such an amount of energy at such a tiny level that an extremely unstable black hole can be created for an infinitesimal period of time. This object does not have close to enough energy to suck anything into it. Even if the black hole created was a bit larger than an atom, it couldn't do more than take in a few atoms before it expends the energy it has available and "fizzle[s] out".

    The article also states that it is a decently rare experience that rays with enough pent-up energy arrive that a black hole can be created.

    The attempt to generate these black holes ourselves is somewhat of a different matter, but not much. CERN originally got a lot of flak for attempting to do this, since a lot of uneducated people freaked out about the thought of a black hole being created. But, that has since died down because it was so long ago and, annoyingly, the average person is kinda forgetful :).

    Now, onto the good stuff. The black holes that CERN is attempting to generate are the equivalent of those that the article talks about that the PAO is trying to detect. Why it won't hurt us is due to the nature of black holes and how they are created.

    A black hole requires an immense amount of energy to be created on a grand scale. That's the reason that only the largest of giant stars will become black holes when nova. The more energy it has in it while in a black hole state, the greater stability is has (though it's likely excruciatingly chaotic, and that's another branch of really fun science :). The ones that will be created will only have a small amount of energy, so little in fact that they could not possibly stay in existence for long enough to do damage. More so, with every particle that is brought into the black hole it requires a specific amount of energy expended by the black hole to drag this particle in. This is, of course, the fun part because no one's quite sure what happens to this particle. Does it disappear from our dimension? Does it come back when the black hole dissipates? There's only one way to find out, and by using harmless black holes so small they cannot do any sort of damage (if it's really damage) to more than a few nearby atoms, we are extremely safe from the attempt.

    Hope you find some solace in all that :)

    - DaftShadow

  19. New Observatory by Y+B+MCSE · · Score: 4, Funny


    Cosmetic rays will indeed prove that the univers is shallow and one dimensional.

  20. A bit more on the multiple universe theory... by instinctdesign · · Score: 4, Informative
    Coincidentally I was just reading an article from a Discover magazine about the possibility of multiple universes. Thankfully you can also get the very same article online from Discover's website. Here is a snippet:
    We also have every possible option we've ever encountered acted out somewhere in some universe by at least one of our other selves. Unlike the traveler facing a fork in the road in Robert Frost's poem "The Road Not Taken," who is "sorry that I could not travel both / And be one traveler," we take all the roads in our lives. This has some unsettling consequences and could explain why Deutsch is reluctant to venture from his house.
    Also, at the end of the article, it provides a few good links for those interested in reading more about Young's double slit experiment. For the sake of being thorough (and those who don't want to read the article) the urls are www.colorado.edu/physics/2000/schroedinger and zebu.uoregon.edu/~js/21st_century_science/lectures /lec12.html.
    --
    forma3
    1. Re:A bit more on the multiple universe theory... by Anonymous Coward · · Score: 0

      This has nothing to do with multiple universes. That's a totally different topic. Why do people always mate these two ideas?

    2. Re:A bit more on the multiple universe theory... by mreece · · Score: 3, Informative

      These are actually completely different theories. What you call "multiple universes" sounds a lot like the Everett "many worlds" interpretation of quantum mechanics, i.e. that we can think of "wave function collapse" as a branching of the universe into different possibilities. Most people tend to think of this more as a way of looking at QM rather than an actual claim that other "universes" exist, and it certainly doesn't suggest any way of making contact with these other "universes."

      The idea of extra dimensions, on the other hand, simply implies that there are more spatial dimensions in the universe than it appears. Of course, there seem to be 3, plus one time dimension, but it's possible there are others that are visible on in small-scale (high-energy) effects. This has nothing to do with other universes.

      --
      Matt Reece
    3. Re:A bit more on the multiple universe theory... by pimpinmonk · · Score: 1

      Are you talking about that the article with the "11 Unanswerable Questions"? That was indeed, at least to me, a phenomenal read. It's based on 11 questions that premier scientists came up with at a recent NASA convention for physicists and astronomers. The article is interesting not only for its mad-crazy science (that's a technical term), but also the convergence of astronomy (ultra-macroscopic) and particle physics (ultra-microscopic) and how they need each other to explain these questions.

      Sadly, it is not up on Discover.com's website yet so I can not provide a link. It is in the latest (February 2002) issue and I highly reccomend it--it definitely re-piqued *my* interest in astrophysics...

    4. Re:A bit more on the multiple universe theory... by instinctdesign · · Score: 1

      These are actually completely different theories. What you call "multiple universes" sounds a lot like the Everett "many worlds" interpretation of quantum mechanics, i.e. that we can think of "wave function collapse" as a branching of the universe into different possibilities. Most people tend to think of this more as a way of looking at QM rather than an actual claim that other "universes" exist, and it certainly doesn't suggest any way of making contact with these other "universes."

      Interesting, sorry about the error... I read a lot of science articles but on a very broad range of topics so I get things confused now and then. Too bad you can't edit posts... shucks.

      Also, I actually have the newest Discover sitting about four feet from where I'm sitting but I have not yet had the chance to read the cover article. (I like to save the most interesting looking for last.) However the article on the new type of holography is absolutely not to be missed either, nor is the article on savants. Got a bit off-topic there... like I said, I have a varied taste. :-) Thanks again for the correction.

      --
      forma3
    5. Re:A bit more on the multiple universe theory... by Anonymous Coward · · Score: 0

      "there seem to be 3, plus one time dimension, "

      That is according to old mechanical Newtonian physics and is how the universe _seem_ to work in "everyday life". But Einstein changed all that and Quantuum Physics goes beyond our wildest dreams of how the universe works. I don't claim to understand General Relativity, but it does claim that space and time is inherently linked in a 4-dimensional spacetime. However, this is by far NOT 3 spacial dimensions + 1 time dimension. Quantuum physics continues the trend to completely falsify the myth of the universe being a clockwork ready to be wind up. QP actually _specifies_ that we can NEVER predict even the smallest particle accurately. That "accurately" is not a property of the universe, but a fabrication of our minds! There are no "elementary" particles in QP. There aren't even "real" particles, only waves of probabilities in a medium we could just as well call Ether, but which is called the Quantuum Field.

      We can't even safely predict much accurately using Newtonian physics, since it's so complicated to calculate _accurately_ with more than two bodies in a system we're forced to iterate and truncate the values. Which the mathematical chaos-theory (and experience) states will make HUGE differences in the result.

      I'd recommend reading Fridtjof Capra's "The Tao of Physics", or some other similar books. They may enlighten you more. Remember, that your model of 3 space-coordinate and 1 time-coordinate is just a very limited model of the universe in your head. It does the trick in most practical situations, but it's not the real thing.

    6. Re:A bit more on the multiple universe theory... by mreece · · Score: 2

      Although relativistic physics does predict a sort of "inherently linked" spacetime, as you say, it is still the case, in a well-defined way, that this spacetime has 3 space + 1 time dimensions. It is not necessarily possible that we can find some global time coordinate and dissect the spacetime into 3-dimensional space "slices", but it is still true that locally spacetime always resembles Minkowski space. The Lorentz group is SO(3,1), the metric has signature (3,1); these things don't change. There is no absolute time or space, but counting the number of dimensions of each type is always possible. We tend to say that spacetime is 3+1 dimensional, but this is not intended to suggest that we can find some sort of global coordinate system with 3 space and 1 time coordinates.

      Ordinary non-relativistic quantum mechanics, on the other hand, maintains the idea of a separate time dimension while treating spatial coordinates as operators. It's only in relativistic QM, and quantum field theory (QFT), that quantum effects and special relativity are reconciled. But this does not take general relativity into account, so QFT actually maintains the idea of global (but not absolute!) space + time coordinates, in a certain sense. We can't determine the position of a particle exactly, however (and there are problems with constructing "time-of-arrival" operators... but I'm getting in over my head with that comment.)

      Also, there are elementary particles in quantum physics. We might never be completely sure that at some huge energy scale, the particles we think are elementary are not composite, but there are certainly particles which, from the standpoint of current theory, seem to be elementary.

      --
      Matt Reece
  21. Random thought: no dimensions, no space by Nindalf · · Score: 3, Interesting

    If we're going to go to such extreme wierdness as space having dozens of dimensions, why not just give up on the concept of position as fundamental quality of a particle? Between relativity and quantum mechanics, we've already lost absolute motion, flat space, and simultaneous exact position and momentum. What still makes so much sense about the concept of space?

    Why not go for a dimensionless graph universe of immutable particles/nodes representing conserved quantities? In addition to mass particles, have energy particles, charge particles, etc. (these are bad examples, of course; given the mass-energy equivalence, a "particle" of kinetic energy would have to be a compound entity). Just set up the rules to define the various types of connections, which have variable quantities (or possibly, are made and broken; however it works out to be simpler) and for determining the probabilities with which they may change from one arrangement to another. To put it in programming terms, take the data out of the particles, and put it into the relationships between them.

    It wouldn't be easy, it might be useless, but I know it would at least give me fewer headaches to start with a clean slate than to twist the classical ideas of space all out of shape.

    You can certainly have a graph system that behaves identically to a spacial system (though a graph system of Newton's physics would certainly be uglier than his elegant concepts), and it would lead to fighting fewer spacial preconceptions that give people such a miserable time keeping up with modern physics.

    Anyway, just a random thought.

    1. Re:Random thought: no dimensions, no space by SevenTowers · · Score: 2

      Relativity and quantum mechanics dump the "classical ides" of space. The problem is that we are thought all our lives to think in those classical bounds. If you look at it from a purely physical, or even purely mathematical point of view, there is nothing classix about the description of space being made. You can't graph the spatial system in any clear way since its more than 3 dimensional...

      --
      Imperium et libertas
      Autocracy and freedom
    2. Re:Random thought: no dimensions, no space by Anonymous Coward · · Score: 0

      There aren't dozens of dimensions. There are eleven. That's less than one dozen, and two less than a baker's dozen, in case you need to brush up on English measures. And every particle DOES have "simultaneous exact position and momentum," it's just that we aren't capable of determining both through observation. We can determine one or the other.

      given the mass-energy equivalence, a "particle" of kinetic energy would have to be a compound entity.

      I can't say I've ever heard a photon be described as a "compound entity".

      It seems that the only person with preconceptions of physics here is you. And those preconceptions aren't the fault of classical physics. Since you like putting things in programming terms, I should call this a user error rather than a software error. Instead of giving yourself a headache doing.... whatever it is that you're doing, you might consider reading a modern book on string theory, or quantum mechanics, or even relativity. I'm sure any of the three will help you understand this.

    3. Re:Random thought: no dimensions, no space by killthiskid · · Score: 2

      Hmm... I think everything is energy. The difference between energy & matter is just perception on our part.

      Matter is just a very tight bundle of energy.

      Matter is also just the property of having momentum and being subject to gravity. It's just a 'mode' of being...

      Hmm... personally, I think it is really interesting to consider how our modes of observation effect our possible theories. What if we were being that 'saw' in terms of microwaves? How would our theories be different? I suppose it would all ultimately lead to the same place.

    4. Re:Random thought: no dimensions, no space by Bryan+K.+Feir · · Score: 5, Interesting

      And every particle DOES have "simultaneous exact position and momentum," it's just that we aren't capable of determining both through observation. We can determine one or the other.

      No, not exactly, though this is a common misconception.

      Heisenberg's Uncertainty Principle has nothing to do with the act of observation. The actual uncertainty is fundamental to the quantum model. It's not that you can't measure both the position and the momentum at the same time, it's more that the particle's wave aspect cannot be constrained by both 'measurements' at the same time. Think of the particle like a water balloon on the position/momentum graph: if you compress it in one direction (measuring position) it spills out in the other (uncertain momentum).

      The fun part is that you can actually use the uncertainty principle to make more accurate measurements. An experiment that was done years ago in Australia proved this. The idea is that a photon travelling here from a distant star has a very narrowly defined transverse momentum: it's heading almost directly towards us, so the uncertainty in its side-to-side momentum is directly related to how much space it takes up in the sky. (Since that defines the range of angles the photon could arrive from.) Since the transverse momentum is highly constrained, the transverse position must be highly spread out. So in theory the photon could be seen as a paper-thin pancake several miles across.

      Now, from the standard double-slit experiments, you get an interference pattern as long as there is a possibility of the photon 'hitting' both slits at the same time. In this experiment, the slits were replaced with radio telescopes on train cars, on a long straight section of track. (Hence why this was done in the Australian outback.) So long as the telescopes are closer together than the uncertainty in the photon's position, you get an interference pattern. Once they're further apart than that, you revert to two seperate streams of photons.

      So, you slowly move the telescopes apart, watching the star, until the interference pattern disappears. Presto, you have the 'size' of the photon, which gives the uncertainty of its transverse position. Back-calculating throug Heisenberg's inequality gives you a limit on its transverse momentum. And that gives you a good idea of the 'size' of the star in the sky, in fractions of an arc second.

      This has been done, and gave answers that agreed with other observations of the stars. So the Uncertaintly Principle has, in this case, improved the accuracy of measurements.

      And demonstrated that the HUP is a lot more fundamental than what you said. Particles simply do NOT have "simultaneous exact position and momentum."

      -- Bryan Feir

    5. Re:Random thought: no dimensions, no space by Anonymous Coward · · Score: 0

      Indeed, people working on quantum gravity have at times tried to get rid of the notion of "space". The "graph of relationships" replacement for "space" that you suggest actually is quite similar to Penrose's original spin network proposal. (He simplified things by considering only angular momentum as a conserved quantity, and studying a network of interactions between spins, taking that network of interactions as fundamental and not postulating that they exist within some space.) Penrose didn't get too far with it; it remains to be seen whether the idea will be realized in practice. (The appearance of spin networks as "quantum geometry" in loop quantum gravity is an interesting, if somewhat different, application.)

    6. Re:Random thought: no dimensions, no space by mreece · · Score: 3, Informative

      Actually, there are some people working on combinatorial quantum gravity models, though I don't know enough about them to be very informative. Look up "spin networks" or "spin foams."

      --
      Matt Reece
    7. Re:Random thought: no dimensions, no space by Anonymous Coward · · Score: 0

      If I may be allowed to speak in terms of reality* for a while, rather than theory -

      The term "dimension" means what?? The common definition is "measurement". Space and real* objects in it are commonly called 3-dimensional (excluding 'time', which isn't relevant to what I'm getting at). What does 3-dimensional mean? It means that the simplest real object can be described by using three measurements. Of course, there are no real objects that can be perfectly described with only three measurements. All real* objects require an infinite number of perfectly precise measurements (dimensions) to create a perfect description of them. It is currently impossible to do that though, and may always be.

      So I ask - What purpose does it serve to redefine the term "dimension" to mean something as nonsensical as a spooky semi-duplicate universe?

      *reality: The really, really, really real. Not theoretical, not definition-warped.

    8. Re:Random thought: no dimensions, no space by Gravityboy · · Score: 0

      The term dimension merely reffers to the number of coordinates to fix an object's position. In the case of these higher dimensional spaces that we're To locate something in the stringy universe you need both it's large space-time coordinates, plus the coordinates as given by the higher dimensions.

    9. Re:Random thought: no dimensions, no space by dragons_flight · · Score: 2

      Position isn't a fundemental quantity. Physicists have known this for a long time. Unfortunately we don't have any idea how to do math or geometry, let alone physics without a concept of absolute positions.

      Quantum mechanics is one way to fudge the matter by saying that we know how the particle is distributed over space, assuming space really had geometric (point-like) positions. String Theory takes this farther by building a structure for the universe where no objects are ever point-like. We believe that this can work because non-point-like objects can be described by the volume of space they take up, but it's probably not the best way.

      Many of us in physics would love a system to represent the world that physics actually takes place in, but we just don't know how to do that so we continue to work in increasingly awkward point based geometries and try to figure out what physics looks like when we impose our artificial framework on top of it.

    10. Re:Random thought: no dimensions, no space by slashdot2.2sucks · · Score: 1

      "Hmm... I think everything is energy."

      You forget all the different kinds of charges.
      You can't throw away 3/4 of the fundamental forces.

    11. Re:Random thought: no dimensions, no space by j_w_d · · Score: 1

      Among other things the experimental production of a Bose-Einstein condensate means that you are mistaken. The Heisenberg Uncertainty Principle is fundamental, not a problem of being unable to juggle measuring tools. The condensate appears because as the particle (atom in the BEC case) is cooled, its momentum can be known more and more accurately. B and E argued that if Heisenberg's argument were true, then as the temperature of a group of particles approached 0 deg. Kelvin, they would blur together because otherwise their position would become known precisely, just as the momentum was becoming a fixed quantity. B and E thought this was absurd, but recent experimental work verifies the conjecture. Karl Popper corresponded with Einstein about this decades ago (1903s) and, in the light of modern experimental work and they proved just how wrong you can be, while being perfectly logical. Check the appendices to Popper's The Logic of Scientific Discovery.

      --
      ------ The only greater hazard to your liberty than n politicians is n+1 politicians.
  22. Argentina -- a bad idea. by juju2112 · · Score: 3, Interesting

    I don't think Argentina is really the best location for a scientific observatory -- they're currently in the process of overthrowing their government. There is rioting in the streets, mass looting, etc, etc. If I was in charge I would want it to be in a country that was much more stable.

    1. Re:Argentina -- a bad idea. by FiberToTheCurb · · Score: 0

      How about Afghanistan? Or Pakistan? Or StanTheMan? Why not Argentina? If it is the way you say, it sounds like they could also study chaos theory.

      --
      "God is dead!" ----Nietzsche "Nietzsche is dead!" ----God
    2. Re:Argentina -- a bad idea. by Anonymous Coward · · Score: 0

      How about Afghanistan? Or Pakistan? Or StanTheMan? Why not Argentina? If it is the way you say, it sounds like they could also study chaos theory.

      Well, in fact, WE actually don't study chaos theory, we only teach it... :)

  23. good show my man! by Anonymous Coward · · Score: 0

    It is good that things like speaking flurbs and a very human choking incident are grounds for determining the leadership ability of someone. Uhhh, Your FAT! I don't like you tie! You suck! I hate people that like Orange Soda, they are EVIL!

    1. Re:good show my man! by Anonymous Coward · · Score: 0

      You're right, of course, but it just gets so old saying "Bush is a republican, and they are pure evil" over and over again.

    2. Re:good show my man! by Pathetic+Coward · · Score: 1

      Remember the ridicule Jimmy Carter got from the killer rabbit?

      At least that was a living creature with teeth!

  24. Possible source of cosmic rays by SevenTowers · · Score: 2

    It has been suggested more than once in the litterature that cosmic rays might actually be linked with the mass repartitionin the universe. Superclusters are aranged in a sponge like maner. Astronomers have and still do wonder how this came to be, since it means either the universe was asymetric in the beginning or somehow became asymetric. Quantum non-locality gives a pretty satisfying answer : As a particle passes in "empty" space, it accelerates. how? well empty space isn't exactly empty, rather it's a swarming soup of particle anti-particle pairs being created and destroyed. The theory goes to say that the particle, over a long period of time, gets accelerated by the absorbtion of these half-photons being created and destroyed. The particles accelerate until they are slowed down by a gravitational field and thus matter conglomerates and empty space gets emptier. Those particles arrive at extremely high speeds and are thought to be the cause for cosmic rays.

    --
    Imperium et libertas
    Autocracy and freedom
    1. Re:Possible source of cosmic rays by barawn · · Score: 4, Interesting

      Unfortunately, this argument isn't very likely. The main problem we have is how to accelerate particles to such high energies - 10^20 and above is impossible by any stretch of the imagination, but the 3 x 10^20 particle that slammed into Dugway, Utah appeared to have a slightly better imagination than humans.

      Empty-space acceleration would have to be massive to counteract the utterly huge deceleration caused by energy loss in galactic/extragalactic magnetic fields, interaction with the interstellar medium, and, most importantly for extreme high energy cosmic rays (UHECRs), the GZK effect - photopion production by interaction with the cosmic microwave background radiation. It's simply not possible to accelerate particles like this in empty space - we would've seen it already in particle accelerators.

      Seriously, physicists right now have no idea how these particles are accelerated. Supernovae? Not nearly enough energy, by any stretch of the imagination - fundamental arguments like conservation of energy kill you far below the 10^20 eV limit. Gamma-ray bursts? Maybe, but the distribution of cosmic-rays doesn't agree with GRBs as a possible source. Extragalactic? Not unless you throw away basic physics and ignore the GZK effect - there's no way they could propagate that far.

      Basically, the one question that there have been tons upon tons of papers in the recent literature for is "where is this gigantic particle accelerator nearby us?"

    2. Re:Possible source of cosmic rays by tashanna · · Score: 1

      >Basically, the one question that there have been tons upon tons of papers in the
      >recent literature for is "where is this gigantic particle accelerator nearby us?"

      Maybe its this interocitor I've got here in my basement. I was using it to make coffee. Sorry about the high energy particles. I'll only make decaf in the future

      - Tash

    3. Re:Possible source of cosmic rays by Sabriel · · Score: 1

      Interesting. Maybe the SETI folks should be looking for signs of ET science experiments instead of ET cellphones. :)

    4. Re:Possible source of cosmic rays by he-sk · · Score: 2
      Basically, the one question that there have been tons upon tons of papers in the recent literature for is "where is this gigantic particle accelerator nearby us?"


      I dont know where it is, but its probably run by some mice.
      --
      Free Manning, jail Obama.
    5. Re:Possible source of cosmic rays by ShavenYak · · Score: 1

      Heh. It would be quite funny if we had wasted all that CPU time looking at wimpy radio signals, when the aliens have been using cosmic rays to try to fax us the blueprints for warp drive.

      --

      Hey kids, there's only 5 days left 'til Yak Shaving Day!
  25. And furthermore.... by Y-Crate · · Score: 4, Funny

    ".....Argentine officals hope to discover new black holes, dimensions and other phenomena, and find new ways to send their debt there."

  26. yes!! by TheQuantumShift · · Score: 1

    Allright, so when will I be able to go to wal-mart and pick up my sliders brand dimension hopper? Just imagine the possibilities of disposing a body...

    --

    Shift happens. Fire it up.
  27. Must resist... by cliffy2000 · · Score: 1

    This is a first... I mean, we get the goatse.cx references on the NORMAL boards, but this is one on black holes! I say this at the risk of losing my precious karma.
    (Humor. Not troll.)

  28. Why should this happen? by GospelHead821 · · Score: 1

    The article was okay in describing the result of these high-energy collisions and the means of detecting them, but what I want to know is why, if there are additional dimensions in addition to the four familiar ones, this should decrease the energy necessary to generate these miniature black holes? Could somebody more familiar with the appropriate theories fill me in on why this should be so?

    --
    Virtue finds and chooses the mean.
    Aristotle, Ethica Nichomachea
    1. Re:Why should this happen? by Anonymous Coward · · Score: 1, Informative

      This article discusses your question in the "Long before the Planck scale" section; the idea is that the size of the extra dimensions brings down the "effective" 4D Planck scale from the usual 10^19 GeV to about a TeV.

    2. Re:Why should this happen? by mreece · · Score: 3, Informative

      The essential reason is that the "fundamental Planck scale" is ~ 1 TeV in LED (large extra dimension) theories. Gravity is a "bulk" field (propagates in all dimensions) while the standard model fields are localized, so this affects them differently. The gist of it is, if you put enough energy in a small enough region, you make a black hole. If there are more dimensions, the size of that region is bigger, so it's not as difficult to make black holes.

      Let me try to outline what's going on: I'm getting this from "Black hole production in TeV-scale gravity, and the future of high energy physics" by Steven Giddings (hep-ph/0110127 on arxiv.org). It's a nice article to start with, if you want to dig into the literature on this.

      (By the way, this is using the "warped" extra dimension model but the general ones are similar.)

      The Planck mass in D dimensions is M_p^(D-2) = (2 pi)^(D-4) / (4pi G_D) with G_D the gravitation constant. It turns out (M_4 / M_p)^2 = (M_p)^(D-4)V_{w}, with V_{w} the "warped volume" of the extra dimensions. (I'm not being very rigorous here; in fact this is how the volume is defined, and the ratio is given by a certain integral in terms of the warped metric.) This is essentially a sort of "Gauss law" argument, over the extra dimensions.

      Now, let's consider a black hole with radius r_h much less than the geometrical scale R_c of the extra dimensions. It turns out that for a black hole of mass M, spin J, in the J = 0 limit, we have r_h = 2 [C M / M_p^(D-2) ]^[1 / (D-3)] where C is some constant in terms of D that I don't want to bother writing. The Hawking temperature looks like T_h = (D-3)/(4pi r_h). This description is valid roughly for M_p > 1.1 TeV - .8 TeV for D = 6 - 10.

      Black hole cross-section was assumed to be geometrical (pi (r_h)^2), but as I mentioned in another post this is questioned (look up papers by Voloshin - but Giddings questions those), and there may be an exponential suppression. Anyhow, the important point is that, once you take all this into account, you get that the cross section sigma grows when D is larger, i.e. you don't have to put energy into as small a region if there are more dimensions.

      --
      Matt Reece
  29. Quit yer bitching. by Anonymous Coward · · Score: 0

    The world isn't going to hell in a bucket. Go get a perscription for Effexer and LIVE a little.

  30. Observatory ?? by Anonymous Coward · · Score: 0

    Well, I'm not aware of any observatory been built in our country. I'm not sure if we have the technology needed to detect tiny black holes. But for sure, our whole country is becomming a very big hole... !!!

    Sad but true.

    Daniel, sometimes Raistlin Majere

  31. Bug by metis · · Score: 5, Funny
    Rumor has it the the code for the sixth dimension has a dangerous bug. An attempt to observe a cosmic ray entering this dimension can cause an illegal cast from a neutrino to a photon.

    The problem is that

    "The result of casting elementary particles outside the inheritence hierarchy is undefined."

    The Manual 4.1, chapter 7 cited in Universe(3)

    --
    -- look, cheese ahoy!
  32. Re:BFD by coljac · · Score: 1

    People probably said that about Aristotle. Wasting his time philosophizing when Greece was going down the tubes - just look at the young people these days. No respect. Lucky people like that only seldom get elected President. :)

    --
    Everyone knows that damage is done to the soul by bad motion pictures. -Pope Pius XI
  33. More info on the Observatory by barawn · · Score: 5, Interesting

    Oh my God, I'm amazed - this is the observatory I actually WORK for, and it's on SLASHDOT, my God.

    Forgive me for going completely crazy replying to everyone, but this is just too cool.

    OK, so long as people promise not to Slashdot the server (heh, that was dumb) for anyone who wants more information, go to the main Auger website, or for even cooler information, go to the Auger site in Argentina.

    Auger is actually a very interesting project, and it's not like anything you'd ever think of - it's a 1600 km^2 array of water Cerenkov detectors (10 cubic meters of water) spaced 1.5 km apart - the picture in the article is of the flourescence detector, which is more like what you think of for a standard detector, but due to the limitations of the flourescence method of detecting cosmic rays, its duty time is only 10%, as opposed to the 100% of the surface array.

    The project is proceeding along... pretty well. We've basically finished the Engineering Array, a small-scale testbed to find all of the design flaws in the initial project (and boy, did we find them) and we've detected some cosmic rays which we believe to be ~10^19 eV. We've also demonstrated the hybrid design as well (events where the flourescence detector triggers as well as the surface detector).

    The black hole stuff isn't the important goal of the project - the goal is to elucidate the spectrum of cosmic rays above 10^20 eV, because we have no idea where those particles come from - all of basic physics says they can't exist. This is one of the big questions in astrophysics in recent years, up there with gamma ray bursts and odd quantum states of matter.

    It's way cool. And not just because I work on it...

    1. Re:More info on the Observatory by Marticus · · Score: 1

      It is quite a shock to see something central to daily life appear on /.

      I have the honour of working on the Cerenkov reconstruction routines, in Fortran no less :)

    2. Re:More info on the Observatory by Anonymous Coward · · Score: 0

      How does the current economical state of Argentina affect the observatory functions?

    3. Re:More info on the Observatory by barawn · · Score: 3, Informative

      Not at all. The Argentine collaboration, while a large contributor to the project, is nowhere near the sole contributor. The largest contingent in the collaboration is (guess who) the US, and so our current guess is that if all hell breaks loose, and Argentina is no longer able to contribute one cent to the project, the US will probably shore up the Argentine portion simply because the investment is so high.

      That, and for those in the cosmic ray research area, this observatory is so critical. At the last ICRC in Hamburg, the rappoteur (sp?) in the "Cosmic Rays >10^19 eV - Upcoming Projects" area said that the one thing that the recent data underscored most significantly is how much Auger is needed. I couldn't agree more - the two largest current observatories, AGASA and HiRes, both have markedly contradictory data, with no clear way to resolve this difference! Previous observatories tend to somewhat agree with HiRes (Haverah Park), but that's iffy at best, as AGASA has some fundamental advantages over the HiRes design. Therefore, it seems extremely unlikely that the international collaboration will let the project suffer for any troubles that the Argentines have.

      It is a little unnerving, though, because for me, personally, the most promising people that I work with down there are the Argentines (and one Frenchman to be left unnamed) - the prospect of losing them due to lack of funding is really worrying. However, it should be noted that the beauty of international collaborations and a small field of study is that you get people moving cross countries to work on a project. There's already one Argentine who just got his PhD and is headed to Colorado, so we definitely won't lose him. :)

      It should be noted - strongly! - that the observatory still is in the construction phase. 1600 autonomous water Cerenkov detectors are difficult - and expensive - to build! We're still working out a lot of the kinks in the design, so right now a lot of the work is being done off-site, though there is PLENTY of work being done on-site as well.

  34. Not really by barawn · · Score: 3, Informative

    The media and the rest of the world is convinced that Argentina is synonomous with Buenos Aires. That, and they're perfectly happy to sensationalize everything as well.

    The observatory is actually in a place along the Chilean border called Malargue (you'll never find it on a map - ever) which (according to all my friends there) is a little bit worried about the goings on in BA, but life, for the most part, seems normal.

    Seriously, the government overhaul is the least of the Observatory's problems - the biggest problems we have are getting things in and out of the country. International customs is horrible. Ever try to explain to someone what a photomultiplier is? Or how something that looks like a very big light bulb is worth $1000?

    1. Re:Not really by mbstone · · Score: 1

      Waving my arms and shouting "Turista! American!" was enough to get an Argentinian Customs supervisor to pull me and my luggage off the Secondary Inspection line at EZE and throw me out onto the street. It's really not a bad country -- the Recoleta section of Bs.As. reminds one of Greenwich Village or SF, complete with street vendors and mimes, except nicer -- and the place will probably be dirt cheap once the Argentinian peso floats 40-50% down in value as is predicted.

    2. Re:Not really by barawn · · Score: 2

      "Norteamericano" is the correct way of doing it - they're american down there too - South American. But, I digress...

      Ezeiza's inspection really has never been anything at all to me - they don't even LOOK at anything non-Argentines bring in, because they don't care - all they're checking for is an excess of the import duty-free limit (which, I've been told, can easily be avoided, like all taxes in Argentina - which is one of their problems). No one has ever even spoken to me in that line - it's just hand over import form, smile, nod, and walk.

      The Recoleta didn't really impress me. I was also extremely disturbed by the number of cats in that graveyard. That's just plain weird. The area was nice, but seemed a little too touristy. Just my opinion though. I love Malargue, though (where the project actually is - in the Mendoza province). It's like a jump back 50 years in time, and the people are all incredibly friendly. The only problem I have is that the geography is so incredibly boring, as Argentina, save for the Andes, is simply ridiculously flat.

  35. Re:BFD by sgage · · Score: 1

    Yes, we live in the best of all possible worlds. Phhhhttttt!

  36. Um... by --daz-- · · Score: 1

    *bubble bubble bubble from the bong*

    Someone's been smoking a *little* too much Argentinian "coffe".

  37. Visualize the hypercube... by TheOnlyCoolTim · · Score: 1

    Here's a fun way to play with extra dimensions... This used to have some nice ASCII art for the first three but Lameness filter encountered. Post aborted!
    Reason: Please use fewer 'junk' characters.
    Fucking lame-ass filter.

    1.) Visualize a line. It has one dimension.

    2.) Now add another dimension. Visualize a square. It has two dimensions.

    3.) Now add yet another dimension. Visualize a cube. It has three dimensions.

    4.) Now add another dimension. Visualize a hypercube. It has four spatial dimensions. Kinda fucks with your head doesn't it? Stuff like this is REAL bad to think about if you can't sleep, by the way.

    Tim!

    --
    Omnia vestra castrorum habetur nobis.
    1. Re:Visualize the hypercube... by evacuate_the_bull · · Score: 1

      if you really want to fuck with someone's head, tell them that line has 2 dimensions (which it does). then draw them a square and tell them it has 3 dimensions. that is, unless you can draw an infinitely thin line, but then you wouldn't be able to see any of the aforementioned. you sure can have a lot of fun with dumb people. sad thing is, they are so dumb you can't get far enough to make fun of their stupidity!

      --
      Satanists get good grades too...suspiciously good grades
    2. Re:Visualize the hypercube... by akiaki007 · · Score: 2, Informative

      Take a note of help from Ken Perlin. And the recent post about Tron should make him happy.

      Quick background info on him. He has worked on texture mapping for quite some time now. Created such things as "Perlin Noise." Here is a good example. He also got an oscar for this work.

      I hope this all helps you visualize the hypercube now. :)

      --
      "Time is long and life is short, so begin to live while you still can." -EV
    3. Re:Visualize the hypercube... by TheOnlyCoolTim · · Score: 1

      That is damn skippy. Anyone with mod points mod those links up!

      The one note is you want to be sure to view that applet in 3d either with 3d glasses or by clicking "Cross" so it goes into "Magic Eye" mode. It's hard enough trying to make sense of that hypercube when it is approximated to 3 dimensions, never mind 2 dimensions...

      --
      Omnia vestra castrorum habetur nobis.
    4. Re:Visualize the hypercube... by Freija+Crescent · · Score: 1

      According to your logic, i could draw a line and claim it to have 3 dimensions, one for length, one for line width, and one as the ink penetrates into the paper. What you get is a highly chaotic 'line' that more resembles a piece of rough yarn.

      -fc

      --
      . echo -e \\04 > /dev/hand1
    5. Re:Visualize the hypercube... by tommck · · Score: 2
      Yeah... my cousin's husband works with Perlin at Improv Technologies . They do some really neat stuff there.

      T

      --
      ---- It puts the lotion on its skin or else it gets the hose again. It does this whenever it's told.
  38. Amazing! by gonzoucab · · Score: 0

    I am really amazed!, is they find that cosmic rays form, black hole at that level of energy. the superstring theory would do a major lap.. we are posibbly closer to a unified theory of fisics.

  39. What if one uncurls? by LichP · · Score: 2, Interesting

    This may sound like a silly question, but would it be theoretically possible for one of these potentially-existant curled up dimensions to uncurl?

    What the universe be like if we suddenly got some osrt of extra spacial dimension?

    Or going the other way, would there ever be any risk of one of our current spatial dimensions curling up?

    1. Re:What if one uncurls? by Anonymous Coward · · Score: 0

      There has been speculation (by, hmm, Brandenberger and somebody?) that the universe started out with all dimensions uncompactified, but some of them curled up to produce the situation we see now.

    2. Re:What if one uncurls? by jakew · · Score: 1

      I'd suspect you wouldn't notice, since you'd have no experience of these dimensions. In effect, you wouldn't be able to see or interact with them. Probably. I may of course be totally wrong, and we might find ourselves in a reality like those distorting mirrors in fairgrounds. But that seems improbably, because that can all be seen in the existing 3 dimensions. Perhaps any effects would have to be 'projected' into 3D so that we can experience them, like 3D to 2D projection on computers now.

      What I'm wondering is would a newborn child be able to experience them? (See Immanuel Kant's Critique of Pure Reason)

    3. Re:What if one uncurls? by Shade,+The · · Score: 1

      Since it hasn't happened yet, I would say it was pretty unlikely :)

      But if it did happen, then we would likely die. The more dimensions gravity acts within, the more the gravitational force increases. I suppose it would be possible to calculate what would happen if this were the case, but being the squishy, frail forms of life that we are, I wouldn't put much hope in our survival. Most likely we would burn up as Earth approached the Sun.

    4. Re:What if one uncurls? by Anonymous Coward · · Score: 0

      There's another theory that we're still in an unstable state following the Big Bang, and that matter might suddenly become impossible or wildly different if a high enough energy event were to shake things up. Basically this state change would radiate outwards at the speed of light until it consumes the universe.

      Of course, it might have already happened, and just hasn't reached us yet.

    5. Re:What if one uncurls? by Anonymous Coward · · Score: 0

      I've heard of this as well, though i should admit i'm pretty uneducated in the area. during the big bang, the original 11 dimensions became the 4 dominant (uncurled) ones we know now, and the remaining 7 which 'curled' up into superstrings (see string theory. interesting stuff). other estimates place the amount of dimensions up around 25. Anyway, going by this 11 dimension model, the other 7 dimensions are comprised of pure geometry. it has been proposed that superstrings are the basis of all matter, and since superstrings are basically nothing, then it follows that we are made of nothing. Frankly i think this last bit is crap, but like i said i don't know much about this area
      can anyone add to this?

    6. Re:What if one uncurls? by Anonymous Coward · · Score: 0

      I think everything in existence would convert into energy since that is the easiest form to exist in.

      altho my example is most likely based on nonsense, but I see it like this.

      If you chance the amount of dimentions, it is like trying to replace all the cement in a brick house.

      The whole house has to be brought back to it's primary state... 'a pile of bricks'.

      So when you implement an extra dimention into existence (which would occour instant and explosively), everything will no longer be stable to exist in the new configuration. everything would fall apart into pure energy.
      probably into superstrings since I read somewhere superstrings have the ability to interact with other dimentions.

      And then we'll have to wait for reality to recreate itself acording to the new dimentional configuration, forming protons, anti-protons, electrons (the new types).

      Now, tell me, how bizarre did my fantasy sounded like?
      Or did I manage to sound plausable?

  40. Re:Visualize the timecube... by underwhelm · · Score: 1

    Once you master the hypercube, see if you can explain to me what the heck this is all about.

    --

    I don't need large brains to have a good time.

  41. In related news... by Geekenstein · · Score: 0

    A project is now underway to build a far more powerful observatory to detect Microsoft's social conscience, Richard Stallman's humility, and Larry Ellison's ability to share the spotlight.

  42. Will do research for food... by supernova87a · · Score: 1

    I just hope that the locals in Argentina don't storm the facility and cannibalize the parts to sell for money. That country is not the most reassuring place to conduct science right now... And photomultiplier tubes go for quite a lot -- recall the accident at SuperK in Japan, where they blew out 2/3 of their PMTs, costing something like $30 M, and a huge experiment downed.

    Astronomers, on the other hand, chose Chile for their telescopes -- a little bit more stable politically, I think?

    1. Re:Will do research for food... by zer0vector · · Score: 1

      Chile is probably chosen not only for its economic stability, but also the fact that most observatories there go up in the Atacama Plateau. Its pretty dry there (hasn't had any measurable rainfall in over 400 years). Plus no rebel faction is going to want to climb up a 16,000 foot mountain, which also happens to be a desert, to steal some radio recievers.

      --

      ----
      Striving to put right what once went wrong, and hoping each time that his next leap, will be the leap ho
    2. Re:Will do research for food... by barawn · · Score: 2

      Not likely - there's really no commercial value in any of the parts. That, and the "facility" is actually 1600 square kilometers of desert/ranch: if the locals stormed it, they'd get attacked by an angry bull (trust me: it's not pleasant to stare at a bull defending a herd).

      Please also realize that Argentina (media) = Buenos Aires, and Argentina (country) = a whole lot more. Malargue, the place where the observatory is located, is about as "politically unstable" as we are - not that that's saying a whole lot. Really don't trust the media as to what's going on in Argentina.

      Also, who exactly would buy a PMT on the black market? They're useless commercially. The only thing of any value commercially in the entire project are the solar panels for power, and they'd be rather difficult to take (and not be noticed by the gauchos - a covert op into a ranch is not exactly easy).

      Finally: SuperK is not downed at all. If you check their Web site, it's an absolute given that they're going to rebuild the observatory. $30M for one experiment that's proven and contributed massively to science is dirt friggin' cheap.

    3. Re:Will do research for food... by Anonymous Coward · · Score: 0

      Since you work on the project, will you answer a question I posted here?

      (Obviously, it would be redundant of me to repeat it.)

    4. Re:Will do research for food... by barawn · · Score: 2

      That link's broken. Can you repeat the question or email me directly?

  43. Extra Dimensions Already Proven!!!! by s1r_m1xalot · · Score: 1

    It has already been concluded by TimeCube.com in an exhaustive scientific process that there are, in fact, four dimensions. The link simply points to a rehash of the cube's pioneering work.

  44. More Gibberish by Anonymous Coward · · Score: 0

    ... From the least intellectually gifted on the planet. Big Bang, Schmig Bang, now we have extra dimensions. Fancy life, getting to sit around in a lab and spout all that all the time.

  45. Re:Visualize the timecube... by Jaysyn · · Score: 2

    Wow!

    + Wierd for sure

    Jaysyn

    --
    There is a war going on for your mind.
  46. UFOs are actually WormHoles by Anonymous Coward · · Score: 1, Interesting

    UFOs are actually WormHoles

  47. This is Terrible! by F34RL3SS+L34D3R · · Score: 0
    There could be a major time paradox that would destroy the whole Universe!

    Hey. Wanna hear the most annoying sound in the world?

  48. Damn tourists! by Dutchmaan · · Score: 1

    You go find yourself a nice quiet dimension and the next thing you know you have people prodding and poking around in it with their little scientific instruments... then comes the invetable "How do we get there?" portion..and after all that you wake up one morning to find your favorite grove of floating trees being torn down so they can put up a White Hen... oh the humanity!

  49. Yes! by 3Suns · · Score: 2, Funny

    Very soon I will be able to travel between these alternate universes, and assassinate all my alternate selves. By doing this, I shall transfer all their energy to my own body. I will be the posessor of godlike speed, strength, and intelligence! It's not murder, I'm just collecting all the excess energy into one container.

    I shall be The One!

    --

    -3Suns

    ~~~~
    The Revolution will be Slashdotted
  50. Could confirm String theory? by chiark · · Score: 1

    Hmm, proving the existence of wrapped up dimensions could be a tangiable shot in the arm for superstring theory which necessitates 10 spatial dimensions and 1 time dimension. If this sort of thing interests you, do read the Elegant Universe by Brian Greene. It's well written and very readable considering the complexity of the subject matter. Hawking radiation is also covered, and a string twist is put on the process. The book kept me quiet for days.

  51. Can't wait. by PrimeNumber · · Score: 2, Funny

    As soon as they find the black holes in our atmosphere, I can reclaim my lost pens, socks and lighters -- maybe even bring back Jimmy Hoffa.

  52. cosmic rays trillion accelerators by peter303 · · Score: 3, Informative

    The most energetic cosmic rays are 10^14 more
    energetic than the largest human accelerators.
    The tradeoff is "luminosity". You may only see a
    few of the highest energy cosmic rays in a year,
    while you want zillions of hgih energy particles
    in an accelerator.

  53. That's not my department by Walrus99 · · Score: 1

    Says Werner Von Braun.

  54. Entropy and Temperature of these black holes. by zippit · · Score: 2, Informative

    Well, from what I know about black holes, as matter passes through the event horizon, the entropy increases. This increase in the black holes entropy translates into an increase in the size of the event horizon. So, as the mass increases, so does the event horizon. At the same time, the temperature of a black hole is inversly proportional to the mass. So the temperature decreases as the mass increases. On the flip side, if the mass is small, the event horizon is small, and the temperature is extremely high. Since we are talking about a extremely small black hole, we are talking about photons being radiated at an extremely high energy in a very short time. Now I understand that the uncertainty principle allows extreme fluctuations in changes in energy as long as it is "paid back" within a short amount of time. But it seems that this extreme "Heat" is being radiated off by extremely energetic photons. In my layman analysis, it would seem that such extreme energies in our atmosphere would be detectable by several means. In lieu of this, I can understand that if there are 10 spatial dimensions, energy is being radiated in all dimensions and therefore in the three spatial dimensions we experience, we would only see a fraction of the total energy radiatated. Now for my question. It would seem likely that the radiation radiates in proportion to the spacial dimensions. If these extra spacial dimensions are soooo small, then they would have only a small fraction of the total energy radiated. Therfore, wouldn't we STILL see a phenomenal amount of energy in our atmosphere from the Black Hole Evaporation???? (Sorry for the length).

    --
    Life is like a box of chocolates. I hate Chocolates!