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Closing In On The Quark-Gluon Plasma

Martin writes "A series of presentations and a press conference was held today at Brookhaven National Laboratory about new results from the Relativistic Heavy Ion Collider. The latest run was finished only a few weeks ago. The results are a new milestone in the search for the Quark-Gluon Plasma, a new state of nuclear matter. The data were analyzed on large Linux clusters at BNL and in Japan and France, with the biggest cluster of about 1100 dual-CPU nodes located at the RHIC Computing Facility. It's nice to see that results are out so soon after the data were taken. There were previous stories about RHIC on /., here(1), here(2) and here(3)."

60 of 264 comments (clear)

  1. Recent events by mao+che+minh · · Score: 5, Informative
    Here is a cool slideshow about the subject from 2000, when the theory was "complete speculation". And here is an article from Sciecne Watch that was written in 2001, when it was considered "somehwat speculative". There wasn't much news about it in 2002. And now, we have this story in 2003.

    Pretty cool.

    1. Re:Recent events by Anonymous Coward · · Score: 2, Funny

      Karma whore!

      We want pictures - here is what RHIC looks like from above-

      http://www.agsrhichome.bnl.gov/Images/RHIC.jpg

  2. Applications? by krisp · · Score: 3, Insightful

    Recreating something that existed at the time of the formation of the universe is facinating and all, but , what are the practicle applications for this research? How will it benifit mankind?

    1. Re:Applications? by The+Only+Druid · · Score: 3, Interesting

      Offhand-

      This sort of physics is relevant to nanotechnology (and the subsequent issues of high-volume micromanufacture, etc.), as well as possibly energy resources (i.e. ZPF if that bears out, etc.).

      --
      "Stumble before you crawl"
    2. Re:Applications? by ciroknight · · Score: 2, Interesting

      It's likely we will never see the benifits of the research we do now. That's just how it seems to go. But in the 23rd century, it may be used to do just about anything........... ;) (Tachyons here we come...)

      --
      "Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
    3. Re:Applications? by Anonymous Coward · · Score: 4, Interesting

      i did my ph.d. in particle physics and this question gets asked many, many times. the typical answer from physicists would pull up something like a tv as an example - the electron tube developed by physicists is the basis for CRT... i don't, however, buy this notion. the easiest answer would be to say, all this is (almost) useless from practical point of view. it's purely for knowledge. anything practical that might come of fundamental research is a lucky by-product. to some people, knowledge is everything. to others, not so. while it may seem a bit unfair that the tax money is spent so "those who seek knowledge for the sake of it" can (it's more like a hobby to them...), i personally think it's for a novel cause.

    4. Re:Applications? by Auckerman · · Score: 3, Insightful

      Sometimes applications of knowledge are either completely nonobvious or impossible to do at the time of the discovery. This is something people need to accept. Much like GPS was impossible to do even after we understood relativity, we may not see the practical results of this or any other fundamental research well into this century.

      --

      Burn Hollywood Burn
    5. Re:Applications? by Bootsy+Collins · · Score: 5, Insightful

      Recreating something that existed at the time of the formation of the universe is facinating and all, but , what are the practicle applications for this research?

      Need it have a "practical application"?

      How will it benifit mankind?

      Well, that's a very different question.

      I don't think this will have any practical value, per se. Absolutely zero. Oh, it's possible that down the road someone much cleverer than I will come up with something. In fact, that's the normal way in which major technological advances have occurred. For instance, when Schottky began studying the quantum behavior of transition metals, he wasn't interested in the tiniest bit in any sort of practical application; he just wanted to understand the implications of quantum mechanics for electrons inside certain solids. If you had asked at the time, "what's the practical benefit of this work?" the answer would have been "zippo." And yet pretty much all of modern technology is based upon the transisitor that was so discovered. That's the way it's always been. Michael Faraday didn't really see any public benefit to understanding electromagnetism, either. Pure research has historically been without such obvious benefit.

      But nevertheless, I don't want to suggest that that's the eventual result here, because I don't believe it will be. I think that would be disingenuous of me. I highly doubt that an improved understanding of the history of the Universe from the Big Bang to the present will ever produce any wonderful and amazing technological advance. To me, the motivation is simply that understanding and knowledge -- especially of something like how the Universe got to be the way it is, and why it works the way it does -- is inherently a good thing. It has value by definition. Perhaps my least favorite thing about our society is that we are trained to evaluate the worth of things in terms of their economic value. Just like love, understanding has its own value, in my mind -- bereft of any "practical" value.

      Let me give you an example of what I mean. To the best of our ability to tell, there's only one place where elements heavier than carbon (such as nitrogen, oxygen, sodium, etc. etc.) can be formed in large amounts -- and that's inside a star. Only elements as heavy as carbon or lighter can be formed in the early universe; for heavier elements, you need a star. Now, if you didn't already know this, stop and think about it for a second. A huge chunk of you, perhaps all of you, was inside a star at one time. It appears that you and I are star debris. And it gets even better. The way that large amounts of these elements, forged within a star, can get out of the star is if the star supernovas -- dies at the end of its lifetime with a big boom. That big boom also serves to make very heavy elements -- such as uranium, for instance -- that cannot be made even in a star while it's burning away. There's uranium, and other similar very heavy elements, on our planet. Do you see what I'm getting at? Much of the atoms that make all of us up, that make this planet up, were at one time inside a star (or stars) that lived its life, supernovaed, and spewed out its stellar debris with heavy elements. Eventually, maybe a few hundred million years later, that stuff is part of our planet, part of our atmosphere, our water, part of you and me. We are all brothers and sisters; we all came from the same place, sorta.

      Now, that knowledge will never make me any money. It will never have any practical benefit in my life. And yet, I consider myself immensely richer for knowing it.

      Understanding has its own value.

    6. Re:Applications? by uberdave · · Score: 2, Interesting

      GPS and Relativity? The two are unrelated as far as I know. Although satelite navigation relies on time beacons, relativistic effects due to the velocity of the satelites, or the gravitational field differences, should be insignificant and irrelevant. Please enlighten me.

    7. Re:Applications? by Auckerman · · Score: 2, Informative

      The difference in the gravitational field of person and the satellites skews the GPS results somewhat. One needs to compensate for this to have a useable result for GPS.

      --

      Burn Hollywood Burn
    8. Re:Applications? by cens0r · · Score: 2, Insightful

      Read this link to answer your questions. To sum this up, the clocks in the satellites don't record the same time as those on earth, because of relativity.

      --
      Jack Valenti and Orrin Hatch will be first up against the wall when the revolution comes.
    9. Re:Applications? by LuckyStarr · · Score: 2, Interesting

      i'm not sure that tachyons are real. some of the string-theories predict that there is no such particle.

      --
      Meme of the day: I browse "Disable Sigs: Checked". So should you.
    10. Re:Applications? by ErfC · · Score: 4, Insightful
      Hear, hear! (Here, here? I can never remember.)

      Richard Feynmann also put it well:

      Science is like sex: occasionally something useful comes out of it, but that's not why we do it.
      --

      -Erf C.
      Cthulu always calls collect...

    11. Re:Applications? by Manic+Ken · · Score: 3, Informative

      It's early (or late..)for me but this is not what I read:
      from the metaresearch link:

      2. What relativistic effects on GPS atomic clocks might be seen? General Relativity (GR) predicts that clocks in a stronger gravitational field will tick at a slower rate. Special Relativity (SR) predicts that moving clocks will appear to tick slower than non-moving ones. Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth. So if a hypothetical clock at Earthâ(TM)s north or south pole is used as a reference, a clock at Earthâ(TM)s equator would tick slower because of its relative speed due to Earthâ(TM)s spin, but faster because of its greater distance from Earthâ(TM)s center of mass due to the flattening of the Earth. Because Earthâ(TM)s spin rate determines its shape, these two effects are not independent, and it is therefore not entirely coincidental that the effects exactly cancel. The cancellation is not general, however. Clocks at any altitude above sea level do tick faster than clocks at sea level; and clocks on rocket sleds do tick slower than stationary clocks. For GPS satellites, GR predicts that the atomic clocks at GPS orbital altitudes will tick faster by about 45,900 ns/day because they are in a weaker gravitational field than atomic clocks on Earth's surface. Special Relativity (SR) predicts that atomic clocks moving at GPS orbital speeds will tick slower by about 7,200 ns/day than stationary ground clocks. Rather than have clocks with such large rate differences, the satellite clocks are reset in rate before launch to compensate for these predicted effects. In practice, simply changing the international definition of the number of atomic transitions that constitute a one-second interval accomplishes this goal. Therefore, we observe the clocks running at their offset rates before launch. Then we observe the clocks running after launch and compare their rates with the predictions of relativity, both GR and SR combined. If the predictions are right, we should see the clocks run again at nearly the same rates as ground clocks, despite using an offset definition for the length of one second. We note that this post-launch rate comparison is independent of frame or observer considerations. Since the ground tracks repeat day after day, the distance from satellite to ground remains essentially unchanged. Yet, any rate difference between satellite and ground clocks continues to build a larger and larger time reading difference as the days go by. Therefore, no confusion can arise due to the satellite clock being located some distance away from the ground clock when we compare their time readings. One only needs to wait long enough and the time difference due to a rate discrepancy will eventually exceed any imaginable error source or ambiguity in such comparisons.
      Different effects cancel eachother?
      Is this what I read. And (this is what I read some where else) we wouldnt do anything different if it we never had GR or SR.

    12. Re:Applications? by confused+one · · Score: 2, Insightful
      So, you can honestly say that having a better understanding of, say for example, QCD isn't worth the effort? And you say you have a Ph.D in particle physics?

      I sincerely hope you're not teaching; because with an attitude like that, all of your students will be tainted with a distaste for advancing science.

    13. Re:Applications? by Idarubicin · · Score: 2, Interesting
      What I read from that is that the clocks on the satellites operate with a slightly redefined notion of a 'second' to compensate for the effects of relativity. Further, for clocks on Earth's surface at sea level, the effects of special and general relativity coincidentally cancel, so that a clock at the pole will seem to run at the same rate as one on the equator. Fair enough, it means that everybody's second seems to be the same length, to an observer at sea level on the earth.

      Nevertheless, someone had to be able to do the calculation for just what the adjusted second should be in the first place--this requires special and general relativity.

      Further, there is a small discrepancy introduced due to relativity for observers not at sea level, or travelling at significant speeds. Presumably, a knowledge of SR and GR would be handy to account for these effects.

      Having said that, we could indeed use GPS with no knowledge whatsoever of relativity. We would notice pretty quickly that atomic clocks aboard satellites seemed to drift, and we could come up with a completely empirical system to compensate. (Of course, this would lead to someone developing a theory of relativity...scientists abhor this sort of unsolved problem.)

      --
      ~Idarubicin
  3. Scary Thought by mgcsinc · · Score: 3, Interesting

    I know it's provincial, but there's just something scary about the thought of harnessing something, and I quote, "1,000,000,000,000 degrees" in temperature on earth...

    1. Re:Scary Thought by localghost · · Score: 4, Insightful

      1e12ÂF is 5.56e11ÂC. 1e12ÂC is 1.8e12ÂF. While any of those numbers could be accurately described as "fucking HOT", it still makes a difference. Whether it starts at absolute 0, or 273ÂK above 0 probably doesn't make any difference at this order of magnitude, though.

  4. Gluons? by grub · · Score: 5, Funny


    I've heard of strap-ons, wouldn't a gluon hurt when removed?

    --
    Trolling is a art,
  5. disappointing by Boromir+son+of+Faram · · Score: 4, Funny

    I was all excited about this at first, but it turns out that it's just a milestone in the search for quark-gluon plasma. I guess I'll have to put up with plain old photon-muon plasma for a couple more years.

    --

    Boromir, son of Faramir, King of Gondor and Minas Tirith
  6. BNL by das_katz_socrates · · Score: 5, Funny

    "The data were analyzed on large Linux clusters at BNL..."

    Who would've thought that the musical group Bare Naked Ladies ran linux.

    --
    This sig has no nutritional value...
  7. "Quark-Gluon Plasma" by GoofyBoy · · Score: 4, Funny

    Give Star Trek writers a larger vocabulary.

    "Captian, it will take at least an hour to clean the quantum-transductor of all residual Quark-Gluon plasma!"

    --
    The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
    1. Re:"Quark-Gluon Plasma" by visualight · · Score: 2, Informative

      This one doesn't seem to be in the catalogue of Start Trek Particles...

      At least not yet.

      --
      Samsung took back my unlocked bootloader because Google wants me to rent movies. They're both evil.
  8. Filter update overdue by jabbadabbadoo · · Score: 2, Offtopic

    Could someone please add the word "beowolf" to the friggin' lameness filter?

  9. Applications ? Oh well... by McSnarf · · Score: 5, Insightful
    ...the most well-known example of pure science known to man is electricity. Why bother with something that can make frog's legs kick ?

    Experience has shown that "pure" research often leads to applications the researchers never imagined.

    Cutting research to areas with "immediate applicability" is quite in fashion in some circles. (The same circles, coincidentally, that do not usually do something for the benefit of mankind. Corporates come to mind.)

    1. Re:Applications ? Oh well... by Tim+C · · Score: 3, Informative

      ...and almost every component in it is based on the results of pure, academic research that was performed with no immediate apparent application.

      The laser, for example, was a curiosity sat around in research labs for a decade or more before anyone thought of anything to do with it.

  10. Also reported in Physics News Update 642 by prestidigital · · Score: 3, Informative

    I don't know what half this stuff means. But I think it's cool that someone else does.

    Here's the body of the email update:

    INTRIGUING ODDITIES IN HIGH-ENERGY NUCLEAR COLLISIONS. Missing
    debris in the smashup between gold nuclei going at close to the
    speed of light suggests the creation of a highly unusual plasma
    environment, researchers have announced at Brookhaven National
    Laboratory. By smashing together gold ions at Brookhaven's
    Relativistic Heavy Ion Collider (RHIC), scientists are attempting to
    make and study a state of matter that existed only millionths of a
    second after the big bang. Called a quark-gluon plasma (QGP), it is
    a hot, dense soup of individual quarks and gluons. In today's
    universe, by contrast, quarks come in groups of twos and threes,
    held together by gluons. This spring, Brookhaven researchers
    performed a "control" experiment, in which they collided a gold
    nucleus with a deuteron, a light nucleus consisting of just a proton
    and neutron. In these and other kinds of nuclear collisions, a pair
    of quarks from a proton or neutron occasionally gets ejected. In
    turn each ejected quark produces a stream or "jet" of particles in
    its wake. In some of the gold-deuteron collisions, the researchers
    indeed observed pairs of jets flying in opposite directions. But in
    head-to-head collisions between two gold nuclei, researchers
    observed only one, rather than two, jets. This property, called jet
    quenching, suggests that the particle jet traveling in the direction
    of the collision region is getting absorbed by a hot, dense state of
    matter. Jet quenching is predicted to occur in the correspondingly
    hot, dense environment of a quark-gluon plasma, but RHIC
    experimentalists are not ready to claim the QGP prize quite yet. To
    verify its presence and rule out rival scenarios, they are planning
    numerous other experiments for finding other signatures of a QGP.
    However, the new data has convinced Columbia theorist Miklos
    Gyulassy that the RHIC team is already seeing a QGP (see
    http://www-cunuke.phys.columbia.edu/people/g yulass y/Welcome.html).
    The gold-gold collisions, he and his colleagues calculate, produce
    an environment 100 times denser than ordinary nuclear matter and
    display properties predicted in QGP models based on quantum
    chromodynamics (QCD), the theory of the strong force which holds
    nuclei together. On June 18, three of the four RHIC experimental
    groups have submitted papers on the new results to Physical Review
    Letters and researchers discussed these new results at a special
    Brookhaven colloquium today. (Brookhaven press release, June 11,
    http://www.bnl.gov/bnlweb/pubaf/pr/2003/bnlpr 06110 3.htm.)

  11. Re:OK... by jandrese · · Score: 3, Informative

    Isn't this the same thing they said about Lasers in the 50s?

    --

    I read the internet for the articles.
  12. Units? by wcspxyx · · Score: 4, Funny
    From the article:

    The top, purple band is the realm where QGP can exist, at very high temperatures above 1,000,000,000,000 degrees.

    Is that in Celsius or Fahrenheit?

    --
    Sig? What sig? Do I have to have a sig!?!?
    1. Re:Units? by Abcd1234 · · Score: 2, Informative

      Given they're physicists, methinks it's in Kelvins.

    2. Re:Units? by red+floyd · · Score: 2, Funny


      "Top Purple Band" would be a good name for a rock band.
      </DAVE-BARRY>

      --
      The only reason we have the rights we have is that people just like us died to gain those rights. -- Cheerio Boy
  13. Weapons? by handy_vandal · · Score: 2, Funny

    ...what are the practicle applications for this research? How will it benifit mankind?

    More to the point -- what are the military applications?

    --
    -kgj
  14. Re:OK... by warpSpeed · · Score: 4, Insightful
    But where, ultimately, does this research lead?

    We will not know until we get there...

    I believe that there is far too little basic research going on these days.

    There is nothing more basic then finding out how all this matter/energy around us works.

  15. Re:OK... by Telastyn · · Score: 4, Insightful

    Well, let's see... One time the cavemen managed to smash certain rocks together and reliably get sparks -> fire. Pretty much the basis of civilization...

  16. you may have to wait for the LHC in 2007 by zptdooda · · Score: 2, Interesting

    âThe scientists are not yet ready to claim the discovery of the quark-gluon plasma, however. That must await corroborating experiments, now under way at RHICâ

    The Large Hadron Collider will hopefully be powerful enough to extend the Standard Model and get direct evidence of the Higgs boson as well.

    --
    Esteem isn't a zero sum game
  17. 1100 dual-CPU nodes... by Anonymous Coward · · Score: 2, Funny

    I think I've just discovered the root cause for global warming...

  18. Parent is a troll by Anonymous Coward · · Score: 2, Informative

    ...Scientists can use these jets to probe your anus...

    These article posting trolls seem to be gaining in popularity lately... Maybe because the mods don't take the time to read them fully before modding them up.

  19. Coolest name for matter ever! by foo+fighter · · Score: 5, Informative

    I'm going to name my band "Quark-Gluon Plasma". All my fans will call it "QGP" for short. It's much cooler than "Bose-Einstein Condensate".

    On a slightly more serious note...

    The article links to a helpful physics primer if you, like me, need a little help understanding subatomic physics. (I'm just have a lowly Math degree.)

    A little googling turned up this awesome page on subatomic particles called The Particle Adventure. This is the most accessible physics lesson I've ever received. Awesome.

    This is the most fun I've ever had with subatomic physics: Quark Dance!

    --
    obviously no deficiencies vs. no obvious deficiencies
    1. Re:Coolest name for matter ever! by SteveAstro · · Score: 2, Funny

      I'm going to name my band "Quark-Gluon Plasma". All my fans will call it "QGP" for short. It's much cooler than "Bose-Einstein Condensate".

      No, the whole point is QGP is much much HOTTER than a BEC.....

      So you won't be a cool band, you'll be a hot band.

      Steve

    2. Re:Coolest name for matter ever! by Josh+Booth · · Score: 2, Informative

      If you really want to read a funny book on physics, I recomend The God Particle by Leon Lederman. It is written by an experimentational physicist, not a theoretical physicist, and is the greatest book on physics. It goes through an entire history of physics, from Democritus of Abdera from ancient Greece, who first hypothecized that everything was made of a-toms (Lederman's spelling for really uncuttable things, not chemical atoms), to modern day (~1993) with the Fermilab particle accelerator. Everything is explained very incrementally and very well, but if you don't get it, Lederman inserts so much humor that it is extremely enjoyable to read.

  20. Actually... by blamanj · · Score: 4, Funny

    The results are a new milestone in the search for the Quark-Gluon Plasma, a new state of nuclear matter.

    ...it's a 13.7 billion year old state of matter.

  21. Re:OK... by Mr.+McGibby · · Score: 2, Insightful

    But where, ultimately, does this research lead?

    Nobody knows. That's why it's called research.

    True, the verification of a theory isn't really that world-changing, especially when the theory turns out to be correct. It's when an experiment shows that the theory is *incorrect* is when the world changes.

    Take the experiments that showed the universe is speeding up. They were simply to try to refine the Hubble constant. No one would've seen that coming. In fact, one might have said, "Why bother ? We know the universe is expanding. How accurate does it need to be?!"

    --
    Mad Software: Rantings on Developing So
  22. Re:OK... by mhore · · Score: 4, Insightful
    What, pray tell, could be the useful results of this research? I don't mean to be critical - I believe that there is far too little basic research going on these days. But where, ultimately, does this research lead?

    I think this is possibly why you lost interest in physics. We're not always interested in the APPLICATION of knowledge. Sometimes, we just like to know why a particular thing is like it is. We leave the application to the engineers and business men.

    --

    Mmmm......sacrelicious.

  23. Basic Introduction by HughJampton · · Score: 3, Informative

    Here's a decent Nature article on QGP http://www.nature.com/nsu/000217/000217-5.html

    --
    In Soviet Russia, beowulf clusters imagine YOU!
  24. Re:OK... by dlakelan · · Score: 2, Interesting

    Yes but lasers don't require megawatthours of electricity to generate. This sort of thing absolutely requires super high energies...

    Therefore there will probably never be a commercial application to quark gluon plasma generation.

    Of course it's possible that some quark-gluon plasma fusion reaction may be discovered that allows us to generate massive terawatt power plants the size of a volkswagen that run off lithium pellets or something, but I'm not holding my breath for that.

    Fundamentally we know enough about physics in this region of the universe to know how much energy we can get from a certain quantity of mass (ie. e=mc^2) and to know the limitations of generating and distributing that energy (ie. conductivity of metals, and cooling requirements of superconductors). From our fundamental understanding of physics as we know it so far, we know that in order to do useful work you have to manipulate the electroweak force (ie. move electrons and atoms around). Fundamentally, all useful chemical reactions and intermolecular forces in our everyday world are electric phenomena. Now THAT's what I call neat physics.

    If you want "Practical" you have to look to the engineering industry. They are the ones creating more efficient power plants, lower emissions engines, higher strength construction techniques, higher efficiency agriculture, and better water treatment systems.

    --
    ((lambda (x) (x x)) (lambda (x) (x x))) http://www.endpointcomputing.com a scientific approach to custom computing.
  25. Those damn humans! by mikeophile · · Score: 4, Interesting
    This is from a report Brookhaven made to define the possible dangers of the RHIC. Oddly, the site seems to be down now. Black holes and stable negatively charged strangelets, while cool ways to snuff the world, don't hold a candle to this one. the report
    This is an exotic possibility of which the report states that "Physicists have grown quite accustomed to the idea that empty space  what we ordinarily call 'vacuum'  is in reality a highly structured medium, that can exist in various states or phases, roughly analogous to the liquid or solid phases of water. . . . Although certainly nothing in our existing knowledge of the laws of Nature demands it, several physicists have speculated on the possibility that our contemporary 'vacuum' is only metastable, and that a sufficiently violent disturbance might trigger its decay into something quite different. A transition of this kind would propagate outward from its source throughout the universe at the speed of light, and would be catastrophic."
    1. Re:Those damn humans! by istewart · · Score: 2, Funny

      Wow... sounds like the Genesis Effect from Star Trek II.

    2. Re:Those damn humans! by confused+one · · Score: 4, Informative
      You know, the reason the link was dead was because this was FUD generated by a few physicist claiming that RHIC could lead to the end of the world....

      It was discredited with the simple truthful statement that a neutrino interacting with matter in the Earth could potentially release more energy than RHIC could generate in it's lifetime. i.e. higher energy reactions than those generated at RHIC occur all the time, all around us; and, we're still here.

      of course, I'm paraphrasing a little...

  26. The obvious will happen. by pixelgeek · · Score: 2, Funny

    -- The data were analyzed on large Linux clusters at BNL

    Which makes one wonder how long it is before we see Microsoft announce Windows XP Nuclear Collider Edition

  27. Not really by f97tosc · · Score: 4, Interesting

    Because it is only a few atoms that have this high temperature. 10 atoms that are 10^12 degrees hotter than the environment can heat up the 10^13 surrounding atoms by one degree. That is, it is enough energy to heat up one nanogram of material one degree. I would not sleep over it.

    This is of course a very rough calculation, but the point is that we are not so much dealing with enormous energies as with moderate energies concentrated to extremely small matter. They are not going to blow something big up.

    Tor

  28. Quark by eclectic4 · · Score: 2, Funny


    ...will this new "gluon plasma" be in version 7 then? And how long are we going to have to wait for it THIS time...?

    --

    "The greatest obstacle to discovery is not ignorance - it is the illusion of knowledge." - Daniel Boorstin
  29. Coverage on Ch. 12, Long Island's News Station by StefanJ · · Score: 4, Funny

    Interdimensional Gateway Opens in Suffolk County.

    Elder Gods awake from aeons of slumber.

    Film at Eleven.

  30. History of nucleosynthesis by Bootsy+Collins · · Score: 2, Interesting

    All elements of mass greater than Iron are either a) Big Bang remmnants, b) created by mad scientists with nuclear acclearators. Fusion in stars stops at Iron.

    No. You're correct that, because of the curve of nuclear binding energy, you can't produce anything more massive than iron through fusion. But that doesn't mean heavier elements than iron come from the Big Bang. In fact, atoms heavier than carbon cannot be produced through Big Bang nucleosynthesis; H through C is all that's around when the first generation of stars form. Elements heavier than iron are produced in high-energy nuclear reactions that occur during supernovae. This is standard contemporary astrophysics, from any current textbook.

    For an overview of Big Bang Nucleosynthesis, see e.g. The Early Universe by Kolb and Turner, or Cosmological Physics by John Peacock. Pitched at a lower level, try Joe Silk's The Big Bang . For more general descriptions of nucleosynthesis in stars and supernovae, see e.g. Harwit's Astrophysical Concepts or Bowers and Deeming's Astrophysics, Vol. I: Stars .

    1. Re:History of nucleosynthesis by Bootsy+Collins · · Score: 2, Interesting

      The remnants from the Big Bang are only hydrogen, helium, and maybe a little lithium (I'm not sure about that).

      You synthesize nuclei up to carbon in Big Bang Nucleosynthesis, but the mass fractions produced above helium are *very* small. The hydrogen mass fraction is about 0.76, the helium mass fraction is about 0.24, and the lithium mass fraction is about 1e-6. Beryllium, boron, and carbon are significantly less than that.

      But despite the low abundances above helium, observers do go hunting for these relic abundances (of lithium, anyway); see e.g. papers by Doug Duncan's group at the University of Chicago on lithium abundances in old halo stars.

  31. Requisite SCO Bashing Humor Post by Nom+du+Keyboard · · Score: 2, Funny
    The data were analyzed on large Linux clusters

    SCO adds the entire branch of physics to their lawsuit maintaining that all discoveries made with Linux software belong to them.

    Their suit against God for creating a world where Linux IP was infringed is on hold while they attempt to hire Dilbert as their process server.

    --
    "It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
  32. It isn't the action, it's the knowledge by forii · · Score: 2, Interesting

    Yes but lasers don't require megawatthours of electricity to generate. This sort of thing absolutely requires super high energies...

    Therefore there will probably never be a commercial application to quark gluon plasma generation.


    It often isn't the actual scientific experiment that is important, it's the knowledge that is gained through that experiment. For example, and this is slightly related to this experiment, in the 30s Stern and Gerlach sent a beam of hydrogen atoms through an inhomogeneous magnetic field and detected the nuclear magnetic moment. Later on Rabi sent a beam of LiCl molecules through oscillating magnetic fields to test if there was a magnetic resonance effect happening at a certain frequency.

    Now neither of these experiments are used in applications today, but what they did do is establish the foundations of Nuclear Magnetic Resonance, which today is used every day in MRI machines around the world. And while none of which use high energy beams in their operation, they wouldn't exist if it wasn't for the use of "non-applicable" experiments.

  33. Band title.. by efuseekay · · Score: 2, Interesting

    hehehe, we physics students have a nice time thinking about band names from physics jargon. OUr favourite is still "The Naked Singularity."

    Btw, the naked singularity is a concept from general relativity : it is the point in spacetime where Einstein's equation blows up and makes no sense. All blackholes, mathematically, have singularities in the middle, but they are "hidden" behind the event horizon, so a guy who fall into the blackhole may see the singularity, but will never get out to tell his friends outside the black hole. A naked singularity is one that is not "hidden" by an event horizion.

    There is a conjecture, called Cosmic Censorship that says that naked singularities do not exist in nature. It is not proven. ALso, Cosmic Censorship is a great name for a band too :)

    --
    Mode (3) smart-aleck mode. Press * to return to main menu.
  34. Not exactly by MickLinux · · Score: 2, Interesting

    To the best of our ability to tell, there's only one place where elements heavier than carbon (such as nitrogen, oxygen, sodium, etc. etc.) can be formed in large amounts -- and that's inside a star.

    I don't have a lot other than my (very faulty) memory to back this up, but I seem to remember a Scientific American article that most of our heavy elements were formed in the shock waves of supernovas of the first round of stars. Not only that, but the progress of the supernova shock wave creates large clumps of specific types of elements.

    But most of us was not inside a star at one type, hydrogen possibly excepted. Most of us was most likely formed in a shock wave.

    But your point still stands: you feel immensely richer for thinking you know what you do. [Sorry for that small withdrawal from your bank account, but the interest that will accrue from your *knew* imagined knowledge will accrue at a much faster rate.]

    All joking aside, we don't *know* anything, but we have our theories, and those theories do help us feel at home within our universe [much like my fish in his tank feels very uneasy when I drop a ping pong ball in the water, but later feels at home with it], and that makes us more comfortable.

    --
    Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's
  35. Re:Come on you guys! by Tim+C · · Score: 2, Interesting

    I must say that the nature of ~ 80% of the posts here is completely misinformed crap!

    You're being rather generous there.

    I have a degree in Physics, and the amount of utter tripe regurgitated here whenever there's a science-related article is astounding and frankly upsetting. I'm not just talking about people getting subtle matters of cutting-edge stuff wrong - I mean fundamental misconceptions on the sort of stuff I learnt at school, let alone college or university.

    Mind you, the same happens with programming-related stories. I've been a professional programmer for a little over four years, and was an amateur for a lot longer before that. The signal to noise ratio is much better than in science stories, but some of the misconceptions are still shocking.

    It's got to the point that I barely do much more than skim the front page most days. A shame, really, as I've been here for quite a while, as my uid should tell you.

  36. Re:(OT) Hear hear by klui · · Score: 2, Informative

    It's "hear, hear." "A shout of support or agreement. Originated in the British parliament in the 18th century as a contraction of 'hear him, hear him'. It is still often heard there although sometimes used ironically these days." http://phrases.shu.ac.uk/meanings/178100.html