Slashdot Mirror
Gravity Diluted By Multiple Dimensions?
SEWilco writes: "Why is gravity so weak? Maybe it isn't, but it's diluted by propagating through many dimensions. The theory provides a relatively simple explanation to several oddities of physics, and it should be relatively easy to test. Notice the links at the bottom of the story; one of them mentions that the concept doesn't have a catchy name yet...and we'll be reading more about it soon. Slashdot discussed extra dimensions before, but this concept involves gravity actually propagating into them." I think we should call it 'The Emmett Effect.' There's got to be some lab-coated brainiac out there than can make it happen.
I mean how the hell can you compare two forces with completely causes? It is just as absurd as saying that 1 gram is more than 1 coulomb.
That's right. They're comparing the values of the coupling constants, which are dimensionless quantities (ie. no units), so they can look at things on the same scale. The coupling constant determines the strength of the interaction. (It also has a really bad name; it turns out that it's not constant.)
- W. Blaine Dowler
http://www.bureau42.com
LOL! I always figured humanity's last word would be something like, "Oops."
How about, "What do you mean, it doesn't have an 'off' switch?!?"
I looked into the abyss, and the abyss looked into me--and we both winked.
A proton decays into a neutron by emitting a positron and an electron-neutrino. Welcome to conservation of lepton number, as well as possibly spin.
Don't get your physics off of kiddie webpages.
In this scenario, we have to conserve a few quantities.
- Charge: this is why we have to have a positron, a proton can't just drop to a neutron, we have to conserve charge by kicking off a positron.
- Baryon number: this is why the proton turns into a neutron (although, to do this, you have to add energy, protons mass slightly less than neutrons)
- Lepton number: Leptons in equals leptons out. A positron has lepton number of -1, which is balanced by the +1 of the electron-neutrino.
- Spin: Spin conservation is what led to first the hypothesis for, and then the eventual detection of, neutrinos.
Only some of the conservations can ever be broken, like CP (this is the very slight violation that we think led to the predominance of matter in the universe, as opposed to a perfect balance of antimatter and matter). There's a good physics website out there that lists the current experimental conservation limits, some of them down to one part in a billion or so.Maybe we need a Particle Physics for Slashdotters webpage. Any suggestions?
Dimensions do not have a size. Objects have sizes in a set of dimensions.
Of course dimension have a size, due to the fact that they are either limited in some extent or infinite. For instance time has a definite starting point and may be infinite in size (an open universe) or finite in size (a closed universe with a Big Crunch). Since the Universe isn't infinitely large the three spatial dimensions we're familiar with also have a size.
In superstring theory the compactified dimensions have a size corresponding to the Planck length in usual models - approx 10^-33 metres. There are models in which the size of these dimensions could be much larger, as in the article, and in those the idea in the article could be made to mesh with superstring theory.
The earth is holding back millions of pins plus everthing else as well. It also doesn't seem to get any weaker however many things you put on the earth, or indeed how "heavy" they are.
The problem is, you can't "concentrate" gravity on any one particular object. By its very nature, gravity is a distributed force. Furthermore, because of that distributed nature, gravity won't get weak no matter how much you throw at it. It may be holding down ten pins, or ten trillion pins - at any given distance from the center of mass, the force of gravity will be the same for the former amount of pins as it for the latter.
For this instance, gravity is the same everywhere on the surface of the planet (oversimplifying). So whether you take that pin to Guatemala, Madrid, Tokyo, or Minneapolis, gravity will still exert the same amount of force. Hence, it can be said that the entire force of the planet is holding that pin on the surface (as much force as Earth is going to exercise at any other point on Earth). So you have to consider the thought: an object the size of Earth, with it's hundreds or thousands of billions of tons (I don't know the figure off the top of my head), is holding a piece of paper. Yet, with a little rubbing on carpet, a balloon weighing maybe several grams, or a few dozen grams, can hold that paper up against the pull of the mass of the Earth.
It even seems to be able to hold the moon in place too! In fact, it seems to me that it could hold lots of moons in place.
But that has less to do with the force of gravity. I can put an arbitrary number of objects in orbit around the Earth. All I have to do is make sure that the rate at which gravity pulls them towards Earth is balanced by their motion around the Earth. At close distances, the object has to go really fast. At far distances, the object can go really slow. The strength of the gravity has nothing to do with how many objects can orbit around Earth, only with how far away those objects have to be.
In fact, the magnet *does* sometimes win the
fight over the 2-ton hunk of iron. Ask anybody
who runs a junkyard.
Chris Mattern
I recently finished reading the widely popular book "The Elegant Universe" (here's an Amazon link) by Brian Greene. It starts with the simplest of Newtonian physics, heads over to Einstein and quantum mechanics and then takes a sharp left into string theory, and eventually m-theory. I'm just an amateur, but this book is very readable (someone else mentioned the ants on a garden hose analogy, which is used in this book) and understandable. It generally avoids the intricate math involved and concentrates on getting the reader to grasp the concepts rather than the details. It takes some perseverence to make it through the 400 or so pages, but I highly recommend it.
Whoops, sorry about that. I even previewed the thing before I posted. That's what I get for typing before I've had Mountain Dew.
Sure, having some arbitrary dimensions and fundamental particles entangled in them does seem far fetched. But remember, these are just models. There probably aren't little teensy rings of dimensions upon which some force particles are "caught". It's something so our poor 3-dimensional biased minds can understand reality. Perhaps you're right, and "dimensions" are actually a continuum, instead of cut and dried orthogonal measurements. But I think the human mind needs some model it can innately understand.
It's 10 PM. Do you know if you're un-American?
In large part, the difference in the examples you give is not so much gravity, but other issues. For the insect, their fall is governed primarily by aerodynamic drag - in a vacuum it will plummet directly to the ground, same as the horse. In all cases, the amount of damage sustained is controlled primarily by the 'square-cube' law - the strength of the body's structural components goes up as the square of the size, but the mass goes up as the cube of the size. This means the strength to weight ratio gets worse the larger you get, so the larger, hence heavier objects will suffer worse damage.
...phil
...phil
"For a list of the ways which technology has failed to improve our quality of life, press 3."
Is the correct answer the German???
I'd put up my proof of how I solved it to prove it wasn't a wild guess, but I don't want to spoil the fun...
-- A computer without COBOL and Fortran is like a piece of chocolate cake without ketchup and mustard
Hoagland already mentions this in his physics i think.. Try www.enterprisemission.com
multiple dimensions, huh how about the "Buckaroo Bonzai Effect" now there's a pretty catchy name
Gentlemen, you can't fight in here...this is the war room!!
No brain, no pain!
Actually, I often refer to protons as fundamental particles.
Well, guess what: they are not. And it is not nitpicking, it is absolutely essential to be precise when discussing technical issues.
If experiments reveal smaller particles for which gravity is more important than other forces, then maybe it would be wrong to diss gravity so much.
Ah, so I need to prove to you by experiments the existence of other particles.
However when the article mentions dimensions wrapped inside other dimensions with gravity diffusing from one dimension to another and everything being ~1mm in size you are willing to take their word for it.
And you know why? Because you really are short sighted and insecure. Insecure because these mumbo-jumbo theories only serve to protect other flawed theories which you believe in so firmly. And you are willing to believe anything that will give those theories another chance, because your world would collapse if someone proved them wrong.
We already know that we don't know everything about physical law.
Yes we do. But you also believe that the things we know are correct, whereas I don't make any such assumptions.
What on earth are you complaining about?
The technical inaccuracies of the article.
I guess you never watched Knight Rider.
$ cat < /dev/mouse
I don't think your argument:
is applicable - the square/cube law is certainly true, but its implication for animals is that their supporting structure size must increase - so a horse is as strong as an insect, but because its fall is dominated by gravity, its impact speed is such that it's a much greater force than it normally experiences.See here for more.
Troll? Me? Never...
The Casimir effect is NOT negative energy.
Nor is it a bottomless source of energy, as people seem to assume.
Just because two plates fall towards each other, that doesn't mean that it is negative energy. Potential energy is not negative energy. Otherwise, you could say that potential energy from gravitation is negative energy (hey, stuff falls down, right?)
Also, amusingly, the two plate thing creates an "attraction," but, depending on the geometry of the two surfaces, you can also get a repulsion, where the two surfaces would push apart. The math is really, really ugly, though.
So, again, Casimir effect is NOT negative energy. Also, all of my previous stuff stands. Negative net energies would cause all kinds of things to happen that we just do not see.
Casimir effect is a purely QM phenomenon. In a very weird way, it's like the Van Der Waals forces. I'm not sure if you've ever done the basic blackbody stuff, but, imagine a box, say the size of the universe, with two metal plates floating in the midst of it. You can have all kinds of allowable, full wavelenghts of photons (virtual, hey, this is QM) on either side of the plate. Big wavelengths, light-years long. Little ones, nanometers long. Anyway, the possible push that QM allows on the plates is just a little bit bigger than the push generated by the possible push between the plates, thus generating what appears to be an attraction (really just unbalanced pushing from both sides).
The jury's still out on that one.
Well...
As I understand it, QED (Quantum ElectroDynamics, which is the basis of quantum EM theory) makes the assumption that EM propagates through space as a background, not affecting the metric through which it travels. In other words, it assumes that EM doesn't bend space and time.
QED's prediction of the EM coupling constant has been verified out to at least a dozen decimal places as far as I know, and that was over a decade ago. If EM does have any effect on the local space-time metric (aside from the fact that photons have energy, which equals mass, which means they should generate gravity in sufficient concentration), certainly nobody's been able to detect it as of yet.
Part of the reason that nobody's been able to come up with a workable Quantum GravitoDynamics theory is that gravity does affect the local metric of space and time. This means one of the basic simplifying assumptions goes right out the window. EM may have gravity's range (the other two fundamental forces use massive particles as intermediaries, and so don't have an infinite range), but it doesn't affect the underlying structure the same way. At least, not to any significant degree.
-- Bryan Feir
Dimensions do not have a size. Objects have sizes in a set of dimensions.
Saying a dimension has a "size" is an unfortunate wording born in an attempt to reach a broader audience. Dimensions have scales. I'm a little fuzzy on this part, since I'm in particle physics and not cosmology, but the idea is that the other dimensions could be "curved in" on themselves in such a way that their existance would be masked from our perceptions. I have yet to find a decent layperson's explanation for this, but I'll keep looking. The mathematical gymnastics in the theory do lead to characteristic length scales.
- W. Blaine Dowler
http://www.bureau42.com
OK, the statements are wrong, but they were still taught to me when I was starting Physics.
:-) an expansion brought in relativity and everyone was happy again.
It's true of the entire field - even early on the laws of motion were taught at such a level to be considered wrong 2 years later futher up the school.
The point is that the simplefications work to a degree - look at the law of gravity that we are looking at just now - it worked fine for ages till astronomers realised that Mercury didn't quite fit the formula. Years later (in sixth form
What I'm trying to say is that while over simplification can be interperated as 'wrong' it can also help a beginner understand the basics of what is going on.
just my lil bit,
Avendit22
The four forces, in order from weakest to strongest, are
Sex. death and guilt were unified early in the 1800's. Gravity remains ununified.
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"I used to listen to Null Device before they sold out."
When I calculate, I do. However, using it here would defeat the purpose of relating things to constants people know from high school physics.
- W. Blaine Dowler
http://www.bureau42.com
I don't have the answer to your question, but maybe this will help: They say if you travel far enough you will eventually meet yourself.
The formula for calculating the gravity between two objects from Newton is:
Fg = G * m1 * m2 / d^2
Fg - is the force
G - is a constant that is very small (about 10^-11)
m1 and m2 - are two masses of objects attracting
d - is the distance between objects
Gravity acts between every two objects in space. Even between you and me. But because G and our "weight" is so small, we can't notice the gravity. It is very weak force.
But when gravity acts between the Earth and you, the Earth's mass is very very big and the gravity is noticable. If the gravity would be a strong force, then you'd probably change into a pancake.
We rearrange this equation:
Fg=(G*m1/d^2)*m2
(G*m1/d^2) = g ~ 10 m/s
So we get the good old (and very simplified) equation:
Fg= g * m
But the word weak is very relative. You must compare gravity with the other forces. And relatively it is very weak.
Gravity is related to mass, and electromagnetic forces on charge. How can someone compare the mass of the earth with the charge in the atoms in a magnet? They are totally different things
Not quite: you can compare the gravitational force of an electron or proton to the electric force effecting it. If you compare the repulsive force between two electrons to the gravitational force between them, you'll get around 10^40 ratio.
The notion sounds deceptively simple: besides the familiar three dimensions of space there may be other dimensions, too small to see yet perhaps as large as a millimeter.
Dimensions do not have a size. Objects have sizes in a set of dimensions.
It is true by your perception of a dimention it doesn't have size, since you're used to think about infinite dimentions. However, imagine a dimention is wrapped around another dimention, and thus creates a loop - this loop have a limited size - after one milimeter of movement along this dimention you return to your initial point. So this is how dimentions may have size.
Sela
> So while gravity allows us to detect the presence of other universes, they do not merge with ours because no strong, weak or electromagnetic interactions can occur across universal boundaries.
What would happen if a super-massive object in the other universe passed "near" the earth? Could the gravitational leakage cause us any problems? Could we get sucked into a black hole in the center of a galaxy a gazillion light-years away?
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Sheesh, evil *and* a jerk. -- Jade
Mass = energy
Charge = energy
Johan V. (who sometimes likes to cut away all the syntactic sugar generally referred to as English, although it's not a wise thing to do from a Karma point of view, but who cares about Karma anyway, enough rambling, I hope the message was clear and stuff)
The real odd question is that gravity is only weak at large distances, such as that which we see in every day life. Down on the subatomic scale, everything gets flipped over. Gravity becomes stronger than all of the other forces.
This presents a problem for those who want to find what lies at the heart of matter (what comprises quarks, for instances) because no useful theory for how gravity behaves at those levels has been developed yet.
I'm pretty sure you meant to type protons, just wanted to clarify, since photons have no charge to repel each other with, and it was a little confusing. :) It must have been Win2k.
You don't get it. The article is basically comparing the mass of the magnet to the mass of the earth. The mass of the magnet is irrelevant: it's the charge that matters. And the article doesn't say how much charge the magnet has, just how much mass it has. So it's a totally stupid argument.
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GetSystemMetrics(SM_SECURE) == FALSE
Oh come on !
Semi mystical garbage ?
Listen to yourself ? Ever heard of the Einstein/Rosen Bridge efect ? The theory of parallel universes, based on the concept of multiple dimensions was an Einstein theory !
I really get ticked of when people try to hide their ignorance behind other peoples genius. Are you aware that Einstein divided by zero in the orriginall theory of relativity, something that was only discovered 30 years later by a 2nd year physics student (sorry, can't remember his name) Einstein acknowledged throughout his life that he is not infallible, and expansions upon his theories had always done him proud. What makes it sacrosanct now ?
Here is a litle something else for you, in 1891 Jules Verne (One of the Godfathers of SCI-FI) wrote a story called Paris, which his publisher rejected because "it was too unbelievable"
He described Paris in the 20th century as a city where everbody has electric lighting (back then the lightbulb had yet to be invented) and cars (which was a brand new invention). The manuscript made headlines a few years ago when someone decided to publish this, pitty Verne could not live to see it. Get the point ?
Science Fiction has a lot of Science in it. And has been the inspiration for many inventions (more recently voice-recognition software, which in the 80's was considdered completely impossible)
And frankly this theory tends to make sense, even to someone who doesn't understand the maths behind it. Yeah, I admit where my knowledge falls short - try it sometime.
PS. I would like to propose the name "Chrighton Efect" I'm sure Michael will be writing a story about this soon, and thereafter make a sucky movie version.
"Semper in excretum set alta variant"
fuckhead
It was Win2K combined with the "it's not even 8am yet" factor!
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
a force is (in newtonian terms) mass*acceleration and acceleration is the rate that speed changes over time so forces don't equate to speed. look at a car that has a 0-60 in 4 secs this means that it is accelerating at a rate of 60 mph/4sec which would mean that it exerts a force of its mass times that acceltation.
Don't mention it. :) I'm a physics student now, but I plan to work in Academia. I enjoy teaching (informally, and as a lab TA), so I take every chance I get to practice for the times when it's my job to make sure someone understands something.
Besides, I don't see the point in flaming someone because they took different classes than I did in high School and University. What's the point? If you're asking questions now, you're trying to learn. Why should I discourage that?
- W. Blaine Dowler
http://www.bureau42.com
The article talks about how we see the effects though gravity...it mentions that this could explain cold dark matter which by definition can only influence other matter through gravitational effects or by very very rare collisions with other matter
While in three spatial dimensions, gravity obeys an inverse square law -- if you halve the distance between masses, the gravitational attraction between them quadruples; cut the distance to a third, and the force increases nine times -- in four spatial dimensions, gravity increases or falls off as the inverse cube of the distance. With each additional dimension, the inverse law increases.
oh yeah? so in 2-D it's the 'inverse law' (1/dist^1) and in 1-D the 'constant law' (1/dist^0 = 1)??
This is nonsense!
It all depends on what norm you are using. What tells you that in these other dimensions - if they exists - the Euclidean norm should be used??
Two extra dimensions need only extend about a millimeter for gravity to be comparable in strength to the other forces.
It really hurts to read this stuff: "two dimensions extend a millimeter". WTF??? since when have dimensions got lengths? Some dimensions aren't even measured in centimeters (->time).
Da Warez D00d
living in the 5th dimension of Software
Actually, no its not nonsense. Gravity and the Electrstatic force are both measured in Netwons(N) -- that is, (kg)(m)(s)^(-2). Or, kilogram-meters per second-squared. Thus, they can be compared. However, I see your point. I believe what you are concerned about is the density of force -- that is, force per size, etc. Well, if you take an electron in the hydrogen atom, it is a valid comparison to compare the electrostatic force attracting the electron to the nucleus with the gravitational force attracting the electron to the nucleus. The electrostatic force attracting the electron to the nuclues is: (k)(q1)(q2)(r)^(-2). The gravitational force attracting the electron to the nuclues is: (G)(m1)(m2)(r)^(-2). Both an electron and a proton have an absolute value in Coulombs of ~1.602EE-19 Coulombs. An electrons mass is on the order of 10^(-31). A protons, on the order of 10^(-27). [I don't know the precise values off the top of my head]. k is an electrostatic constant. G is a graviational constant. Thus, the net electrostatic force attracting the electron to the nuclues is much smaller than the net graviational force attracting the electron to the nuclues. However, you may still accuse me of making an invalid comparison, if you carefully look at the two equqations: F(electromagnetic) = (k)(q1)(q2)(r)^(-2) F(graviational) = (G)(m1)(m2)(r)^(-2) In my example, the electron in the Hydrogen atom, the product of q1q2 was not equal to the product of m1m2. Thus, the comparison may be said to be invalid. However, even if such hair-splitting is employed, it is still obvious that Gravity is an inherently 'weaker' force than electromagnetism. Let us say that we have an object of 1kg and 1 Coulomb; and another of 1kg and -1 Coulomb. Let us say they are 1m appart. These two objects would be attracted to eachother by both the graviational and the electrostatic force. F(g) = (G)(1kg)(1kg)(1m)^(-2) F(g) = (6.67E-8 Nm^2/kg^-2)(1kg)(1kg)(1m)^(-2) F(g) = 6.67E-8 N F(e) = (k)(1C)(-1C)(1m)^(-2) F(e) = (8.99E9 Nm^2/C^2)(1C)(-1C)(1m)^(-2) F(e) = 8.99E9 N Clearly, even given a perfectly level playing ground in terms of the absolute magnitude of the mass/charge, the graviational force is much weaker. It is interesting to note that both these forces approach infinity as the radius -- that is, the distance between the two object's centres -- approaches zero. This is the concept behind a black hole. Because a black hole -- or singularity -- is essentially a large mass concentrated at a singular point, the gravity is very strong round that point. For example, being 100 meters above the surface of the earth you would feel little force. But being 1000 meters above the "surface" of a singularity, you would be stretched out like a sphagetti. This is because with the earth, you are farther away from its center. Such also shows why it is *impossible* to dig through the moon. As one starts digging down into the moon, the gravity becomes much stronger, as one is approaching its center(at the center of the moon, gravity is infinite). Eventually, as one digs down to the center, the gravity becomes too much to bear: it will crush one's body like you would squash a bug, turn your bones into dust, and do other unpleasant torturous things to you.
social sciences can never use experience to verify their statemen
Does antimatter have negative mass?
No, antimatter has normal mass.
"Antimatter" is a misnomer. It isn't a different form of matter, really, and it isn't a true mirror image of "normal" matter. What makes antimatter different is that an antiproton simply has the opposite charge from a proton. A proton has a charge of +1, an antiproton has a charge of -1. In most other respects, protons and antiprotons are identical. Certainly, they are both massed objects.
What happens to all the energy that is released in a matter-antimatter collision? Since mass cannot just appear out of nowhere, (1st Law of Thermodynamics?) and can only be converted from energy or energy to matter, wouldn't it stand to reason that since the matter got converted to energy, that the anti-matter got converted to anti-energy?
No. All the energy that is released in a matter-antimatter collision is given off in a burst of light and heat (mostly heat).
The weird thing is is that if there is no such thing as anti-energy, what happened to the antimatter?
It is simply destroyed, with the mass of the antimatter and the matter (the antiproton and the proton) being converted into the light and heat energy given off by their collision. The first law of thermodynamics.
The part in the article that bothers me the most is the claim that gravity hasn't been measured at distances smaller than a millimeter.
/dev/null 2>&1
I remember reading about an effect that could be measured with a table-top setup. Take to plates and put them really close together. At some distance, they are pushed together without any added force. The explanation was that the photon pressure (or was it some quantum effect?) on the outside surfaces of the plates was larger then the force pushing against the inside surfaces because the gap between the plates was smaller then the wavelength of the ( particle | force ).
Why not measure gravity at sub-millimeter distances by taking two plates, placing them inside a vacuum chamber that is electromagnetically shielded, including light. If you have a mechanism to very slowly push the plates together, you could put something like springs on each plate and measure the pull the springs are exerting(sp). Taking into account any friction, the force used to move the plates closer and the tension the springs create, shouldn't you be able to measure the tension on the springs to see if the plates pull on the springs with extra force at small distances?
A millimeter is about how thin a dime is. It's small but we have micrometers that can measure much smaller then that, surely we have devices that can measure very small forces like tension on a spring. All you would need to know for this experiment would be the tension created by the spring along the same distance without the plates to compare with the tension created by the springs with the plates.
Kelly
Ideas? Questions? Rants? Raves?
rants >
We the Sheeple...
It was a pretty good original post. But the downside is that the record companies and artists wouldn't make as much money as they normally do now (unless of course someone wants to buy the song at a few million).
I also must agree about the moderation. There's no way to stop it. Most people moderate only new articles, and then only moderate other posts that have been moderated up (me-too syndrome).
"Evil will always triumph over good, because good is dumb." - Dark Helmet (Spaceballs)
There is still the problem of how do you know gravity pulls and its not the result of something else pushing? All I'm asking for is a simple proof.
Take a simple example. A verticle pipe full of water that is caped on the bottom will push on the sides of the pipe and we say the water is applying pressure on the sides and that is base on the weight of the water because we know how gravity works with fuilds in the macroscopic world. Now if we didn't have thouse nice equations and the knowlege to back it up, how could you describe the pressure on the pipe? How would you know it pushes or isn't pulled by some magic force? Today we say gravity pulls on the water through the pipe but modern plumbing design is based on the concept that the water is pushing on the bottom of the pipe.
I see current gravity theory like the last stages of chemistry before Bohr came up with his idea about electron orbits. He wasn't quite right but he was much closer than the others in his day.
I don't know what it would be, but I think science should call something The Reindeer Effect. That way, maybe someday, someone would get to say, "Gentlemen, what I think we have here is a terrifiying example of The Reindeer Effect." -Deep Thoughts, By Jack Handy (paraphrased)
Education is the silver bullet.
...the Slashdot Effect, already known to dissipate the strength of powerful servers.
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What? WHAT?!! Oh.
LOL! I always figured humanity's last word would be something like, "Oops."
"There is no shot you can take that I cannot simply deny." - Ertai, wizard goalie
Ah, now I get it... I hadn't though of that, you're right.
The illegal we do immediately. The unconstitutional takes a little longer.
--Henry Kissinger
Could someone give me some background on what precisely makes gravity weak? I never thought of it as anything but normal before. :)
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NeoMail - Webmail that doesn't suck... as much.
Unfortunately, at this point all 7 other dimensions are filled with unpaired socks, lost keys, and pocket change.
Mr. Ska
Oh wait, that's always repulsive!
Sorry
Or he uses a different definition of "science fiction" than people who label Knight Rider that way. I prefer the general term "speculative fiction" for most of what Hollywood calls sci-fi. This is any premise built on the "what if the world was just a little bit different..." idea, and includes all of science fiction, as well as fantasy, alternate history (if you consider that outside the sci-fi realm), etc. When I refer to science fiction, I usually mean to "hard science fiction," which is something that can be built upon (and does not violate) the known laws of science. That means that anything which has sound in space is immediately tossed out of sci-fi and into spec-fi, for one example.
- W. Blaine Dowler
http://www.bureau42.com
Based on the numbers given in the article, Gravitational Attraction can be represented as:
Ga = (L)^-(d-1)
GA = Gravitaitonal Atraction
L = reduction Amount
d = the dimension
(reduction amount to the power of the dimension minus 1 negated)
If you were to reduce the distance of 2 objects in the seventh dimension by half, the attraction becomes 64. That a lot of gravity. It would be interesting if they could prove this, but would there be any real change in our lives? This is just my simple formula based on the limited information from the article.
At the next eco-hypocrisy-meeting, count the private jets used to get to the meeting. Should be interesting to see that
Perhaps the "reinforced wall" you're looking for is the fact that the strong, weak and electromagnetic forces do not "leak" between universes. So while gravity allows us to detect the presence of other universes, they do not merge with ours because no strong, weak or electromagnetic interactions can occur across universal boundaries.
$ cat < /dev/mouse
Honestly, even with a doctorate in particle physics behind me, after attending lecture on this subject recently at SLAC, I felt like a dummy. Beats me, some people are just crazy enjoying working on this stuff... Or, well..
<^>_<(ô ô)>_<^>
Well, I for one am not gonna kowtow to some commie pinko extradimensional invader...
Exactly! Remember what the RHIC folks were saying about the possibility their collider could destroy the earth? "Oh, the chances of accidentally creating a black hole that would rapidly sink to the center of the earth and then eat it all up is rather quite small..." And now they want to intentionally make one? Someone take away their keys, quick! *scoove*
I still can't fly, so I guess gravity is stronger than a little ol' wonderchicken. I guess stronger than me is a very relative way of looking at it.
Kate
_________________________ Visit me at http://pornforcomputers.com
Also, I wonder what sort of experiment could possibly test whether these extra dimensions are really needed for grand unification - or whether they're an unnecessary complication.
That's true. I've heard of cases where test audiences in 1970's sci-fi movies thought something was wrong with the print because there was no sound in space. Hollywood chose to run with the most common misconceptions rather than correct them, and now they propogate them. "Sound in space" is the most forgivable error. Nothing like the old Star Trek "he won't remember what happened when we beam him back to the past because it wouldn't have happened yet" cop-out. The sad thing is, Lois & Clark ripped that off thirty years later, in the episode where H. G. Wells built a time machine and came to visit.
- W. Blaine Dowler
http://www.bureau42.com
You need MULTIPLE particles to manifest a gravitional force, force is not a property of anything.
Sure, gravity is a function of mass, but it's also a function of distance. To have a distance you need multiple particles.
So, the Earth does not have a "gravity". It has a mass, other objects have mass, and as a result there is "gravity" acting between the earth and another object.
Christ, take any simple physics class, I'm not your teacher...
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You're right. It was Boltzmann. IIRC (all my quantum books are at home, and I'm at work) Einstein was the one who proposed to look at QM effects with statistical mechanics, and not to bother with the individual particles. Of Course, I Could Be Wrong(tm).
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
They said they didn't have a cool name for it yet. I don't see how "The Emmett Effect" could posibly be considered a 'cool name'...
We don't know how bad things are in north korea, but here are some pictures of hungry children. -- CNN
ReadThe ReflectionEngine, a cyberpunk style n
But, it's not actually on Slashdot. Slashdot is merely "metareporting."
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Damn, where is that taken from?
cheers,
G
Although the prospect of such a exciting new approach to gravity and the dark (or rather 'transparent' since it does not absorp light) matter problem, it needs to be stressed that lack of theories and ideas is not the problem.
The actual limit on progress in this field is lack of relevant data, obtained either from super colliders or from deep cosmological observations. Currently it is possible to make many models consistent with the observational constraints because it is these constraints themself which are so loose.
Everybody knows the US killed the giant supercollider program, and the state of affairs in observational cosmology learns that it is very difficult to calibrate measurements of (dark) matter.
To so something more about the last point, since I've researched this last year, it is far from trivial to yield reliably answers on galactic cluster potentials via dynamic or gravitational lens measurements, especially because you need to go into the Infrared to observe (optical) light emitted by stars in the deep universe. Only recently with instruments like ISAAC on one of the VLT telescopes we are able to obtain high quality near-infrared data. For the far infrared imaging space based missions like the NGST are required, because of the polluting thermal radiation from the earths atmosphere. The NGST is still under study and not expected to be launched until 2010!
Until then we can only speculate aboute the nature of dark matter.
Ivo
We are all in the gutter, but some of us are looking at the stars
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Gravity is related to mass, and electromagnetic forces on charge. How can someone compare the mass of the earth with the charge in the atoms in a magnet? They are totally different things.
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Exactly. A person could make the opposite argument - that you can place a rock on the ground and it will stay there, and yet remain stationary when you move a magnet over it.
Or even plop down a 2 ton chunk of solid iron. It's a lot easier to keep it on the ground than to lift it with a magnet.
- Jeff A. Campbell
- VelociNews (http://www.velocinews.com)
- Jeff
Come on, this is not a troll. It's about the first original posting about hotgrits since a very long time.
Johan V.
So now, individual objects have a "gravity" associated with them, I suppose.
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String theory requires 10 dimensions. It's been effectively replaced by membrane theory, which requires an 11th dimension. They weren't brought in to make the math easier, they were brought in to make it possible. String theory didn't quite pan out, but membrane theory is gaining strength.
Part of the string theory problem was that there were five totally separate formulations for the theory. Membrane theory allows all five to be related by "gauge transformations."
A gauge transformation is essentially a freedom within the math. When calculating the potential energy of an object, we need a reference height, generally the height of the lowest place it can go. This is totally optional; we can set "ground level" to be the ground, the ceiling, or the basement. As long as we use the same ground level in all calculations, anything that we can measure or observe will be correctly predicted by the theory.
- W. Blaine Dowler
http://www.bureau42.com
I have a simple question.
Suppose for a moment that, indeed, many universes inhabited this specific multiversee.
Also suppose that certain extreme events would lead to cross universal leakage.
We wouldn't need to wait for a particle accelerator to be built to witness such effects--those stellar furnaces known as stars should be a constant source of evidence for reactions so extreme that they violate the bounds of this 3D environment.
In fact, stellar reactions should be the most mysterious, because they'd contain the most missing energy by far. It's not unimaginable, to be sure. Where I think some things start to break down is that, if there *is* leakgage, the events that cause such things as Gamma Ray bursts would *need* to involve cross universal effects.
A bigger problem actually with cross universal gravity is that it would cause real problems for universal integrity. In order for multiple universes to to exist in parallel to eachother without any kind of "reinforced wall" between those universes, they must grow in parallel to one another and never blur together. But if gravitation in one universe can extend out towards another, there'd be no way for the parallel universes to remain separate--particularly if the forces equated at short distances, the universes would draw together into one.
Thoughts?
Yours Truly,
Dan Kaminsky
DoxPara Research
http://www.doxpara.com
"Little Caesars? You do pizza?"
There's a great collection of essays by a fellow by the name of Michael R. Feltz who describes the possibility that the three-dimensional universe we live in may be built upon a fourth spatial dimension which is expanding. This could also explain gravity if matter is "dragging behind" in this expanding fourth dimension.
Feltz's essays are located at http://www.cyburban.com/~mrf/. It's really worth checking out, as it gives you some great ways to visualize the fourth spatial dimension, and some interesting insight into the possibilities of the structure of our universe.
Sometimes the math gets a bit heavy, but the discussion is worth reading.
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Matter consists of leptons, antileptons, quarks, and antiquarks. Baryons (including but CERTAINLY not limited to protons and neutrons) are built out of quarks and antiquarks, three of them, to be exact. Mesons (a class of particles you have neglected) are made of two quarks. No, quarks don't ever appear singly. Leptons aren't quarks. In the lepton family, we have electrons, muons, tauons, antielectrons (positrons), antimuons, and antitauons.
"Electrons have a negative charge but no mass." Wrong!
Electrons have mass. The mass is smaller than that of a proton, and it would take roughly 1,300 of them, if I recall, to equal that mass, but, yes, they definitely have mass.
Same thing goes for positrons.
Also wrong "a proton is essentially a neutron combined with a positron." First, neutrons weigh more than protons. Second, you're forgetting about conservation of baryon number.
When a neutron beta-decays, it typically falls apart into a proton, an electron, and an electron anti-neutrino.
I agree. How can you prove that time had a starting point? That's like trying to prove how the world began.
Of course, the standard response is, "How can you prove that time didn't have a starting point?"
At best, the proposition is a draw. If I wanted to defend the original post, about time having a definite starting point, my best starting place would probably be with entropy. You can only go from high entropy to low entropy, and never in reverse (which is why you don't see shattered glasses magically reforming). If you accept that the universe has a limited size, and is truly not infinite in nature (regardless of how big that limited size is), and that the universe is expanding, then it implies that the universe is moving from a high entropy to low entropy state. Logically, it follows that at some point a finite-size universe would have had a moment of highest entropy and smallest size - a.k.a., the moment before the Big Bang.
As far as most people are concerned, measurable time in the universe starts with the Big Bang, because that is the moment of highest entropy.
I'm sorry, today is apparently backwards day for me.
Everywhere you see "high entropy to low entropy," replace with "low entropy to high entropy." Entropy always increases, never decreases.
Ehm, excuse me but doesn't the phrase "comparing apples to oranges" come to mind here? I mean how the hell can you compare two forces with completely [different] causes? It is just as absurd as saying that 1 gram is more than 1 coulomb. Gravity is related to mass, and electromagnetic forces on charge. How can someone compare the mass of the earth with the charge in the atoms in a magnet? They are totally different things.
It's true that mass and charge have different units, but what we're talking about here is forces. Mass + gravity == a force, and Charge + EM == a force. Those two forces certainly have the same units!
Dimensions do not have a size. Objects have sizes in a set of dimensions.
True if the dimension is infinite and unbounded. Not true if the dimension is wrapped in on itself (as string theory speculates), therefore finite and unbounded. Consider an infinitely large sheet of paper. It's meaningless to ask "what is the width of the sheet?" unless "infinite" is an acceptable answer. But when the sheet is rolled up into a long tube, it's perfectly meaningful to ask "what's the radius of the tube?" Of course, the unit of measurement is always arbitrary anyway, but if you consider two rolled-up dimensions you can use their ratio as a quantitative measure independent of whether you use feet, millimeter, parsecs or whatever.
That is the strong force, carried by the 'gluons', which have been around for quite some time now, cant exactly remember how long though.
:-)
Gluons have most certainly existed since the beginning of the universe. Sorry, I couldn't resist...
Normally, the photons are repelled from each other due to electromagnetism, since like charges repell. But at small distances (like you mentioned) the strong, attractive nuclear force between the particles overpowers the electromagnetic repulsion. So, if you slam two protons into each other at high energies, they tend to stick. In fact, they release energy in the process by losing the potential energy inherent in their separation (similar to a brick losing potential energy when it falls). That's a rough way of putting it but you get the idea.
The process I just described is two hydrogen ions (aka protons) fusing into one helium ion (2-proton nucleus), which releases the energy of nuclear fusion-- it takes a lot of energy to cause it but you get more energy out than what you put in. That's why if you use a fission bomb as the detonator for a hydrogen (fusion) bomb, it can release 100X the energy of the fission bomb by itself.
Hopefully that wasn't more background information than you needed...
Disclaimer: any inaccuracies in my description of the physics are due to me typing this in Windows2K.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
I searched for the info but could not find it.
Blar.
I am still kinda ticked about the
gee maybe we can make a black hole idea.
But....
If the article is right, and there are multiple universii??? Then would not a black hole be located in both of them? I would think so since it collapses ALL the dimensions into a point....
Now if I can only get my twinkie-transporter to harness the power of a black hole, we can trade glorious golden sponge cakes filled with creme to our neighbors "next" door, and make a MINT!!!!
(Or an inter-universal war) HEH HEH HEH......
Service guarantees Citizenship! Questions Guarantee GITMO.... Amerika Uber Alles!
"Just because the force of gravity is different, or weaker, than the other forces in the universe, right away you judge it and say there is something wrong with it. This kid of bigotry troubles me deeply."
Newton predicting weakening through dimensions? Yeah cool!
Well, as I said I not arguing against theory itself. I'm arguing against the fact that the article shows a clear distinction between three-four dimensions and two more. There is some sort of strange dessimetry in this story. Gravity weakens due to unseen dimensions. And the other three "feed up the boy"???? What the Hell is this? Physics? Einstein is jumping in his grave man. What tells you that one dimension "strenghts" and other "weakens"??? Third Law and similar stuff to the trashcan? And why it looks like that our dimensions strengthen gravity while the two poor "unseen" weaken it? White-necks, niggers, and red-skins in Physics? Too human for the Universe...
Well I like a lot of these theories of multi-dimensional worlds. But such idea of "dividing" dimensions the way it is shown in the article is rather ridiculous.
Jesus. I need to sleep or get laid as soon as possible. This computer shit is bad for your head.
What I'm wondering, is what this has to do with mice? I mean, since it is Science and it was posted on /., it HAS to have a mouse that was genetically engineered, right?
RIGHT?
--
rJames.org - illustration
I am!,
Besides he's German, even if he did live during a time when coke was massly available, he would have never had it cold, just ask a German for a Icecube and you'll find out what I mean
Einstein was never comfortable with quantum theory despite the fact that his own work was part of the lead-in for it. The best way to examine this dichotomy would be to look up the dialogues between him and Niels Bohr.
Despite that however, Einstein didn't have have the cow you seem to be having so chill. What you don't seem to understand is that the leading edge of Physics is happening in areas so esoteric that it's extremely difficult to explain in any language besides mathematics, so naturally it comes out seeming a lot more weird in Human.
On a semi-related note, there's an interesting play by the name of Copenhagen on Broadway about a hypothetical meeting between Bohr, Heisenberg, and Dirac during the World War 2 era.
check out. http://www.copenhagenbroadway.com/
If this checks out, it could lead to a new era of physics research as productive as the first half of the 20th century. Too much of recent work in physics has revolved around explaining cosmology or developing theories that involve energy levels far beyond our reach. But this gravity theory leads to something that can be worked on. That's where new technology comes from.
Science is prediction, not explaination. - Fred Hoyle.
Its one of those riddles that can be easily solved with linear equations. I of course had to see if I could solve it the traditional way which is more fun, and took me about 30 minutes longer than just doing the math would have.
Leptons refer to the "light" particles. There are six leptons known of today, the electron, the muon, the tauon, the electron-neutrino, muon-neutrino, and tauon-neutrino.
Their are six flavors of quarks, the combination of them produces the mesons and hadrons. The mesons are particles like Kaons, they are the middle particles composed of two quarks. Protons and neutrons are examples of hadrons, or heavy particles composed of three quarks.
The 6 flavors of quarks are:
Up
Down
Charm
Strange
Bottom (originally called beauty)
Top (originally called truth)
Each of these quarks have their respective anti-quarks. The proton has the combination of Up Up Down, and the neutron has Up Down Down. Quarks are always found in groups of two or three, the search for a single quark is being conducted but many believe that it will never be found. The last quark to be found was the Top quark, and it was theorised many years before it was actually found. There is a lot of research still be conducted on Top quarks because they are so new to the playing field.
There are a couple other fundemental particles that no one has mentioned. Those are the force particles and the Higgs Boson Field particle.
Both quarks and leptons are considered fermions, which is the classification of any particle with spin 1/2, 3/2, 5/2... The fundemental force particles, the photon, Z, W, gluon, and, assuming it exists, the graviton are considered bosons, or those with integer spin. All of those, except the graviton have spin 1, while the graviton has spin 2. The Higgs Boson is the really wierd one, is theoretically has spin zero, and is the fudge factor for giving particles mass in the standard model (its existance also breaks the standard model because it would technically have infinite mass).
There are theories out there like Supersymmetry which believe that at high energies all fundemental particles and forces have a supersymmetric partner. This supersymmetric partner has +/- 1/2 spin off of the low energy particle/force, so a fermions supersymmetric partner is a boson, and a bosons partner is a fermion. If Supersymmetry is true then we will roughly double the number of elementary particles.
If you want to learn more about particle physics then go to the particle data group site.
Disclamer - Opinion of Person
Do we REALLY want scientist creating black holes on Earth? Look at all the problem in the past that were cause because we didn't understand something completely!!! We'd be asking for trouble!
At the next eco-hypocrisy-meeting, count the private jets used to get to the meeting. Should be interesting to see that
If gravity really is weak because it has to propagate through extra dimensions, why is it that the electrostatic force is comparatively so much stronger? I mean, they both follow inverse square force laws on macroscopic lengths so why should they scale differently as we probe smaller and smaller distance scales?
Perhaps the answer to my question lies in the properties of the underlying gauge bosons which mediate the field. The graviton is supposed to have very different properties from the photon (eg., the graviton is spin 2 while the photon is spin 1) so perhaps this would explain the discrepancy in scaling behavior necessary for this theory to work.
I often used what's known as Cp, or the CausticPuppy constant, which is unitless.
It's not a universal constant, since its value changes from problem to problem, but it is a constant within the scope of any one problem.
Cp is the value by which you multiply your answer in order to equal the answer given in the back of the book (or the "expected result.")
It's best used if you bury it somewhere in the middle of the math, because hopefully the TA who's grading the papers won't follow too closely.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
Sorry I only reply now, had to go to a (useless meeting) I think you misunderstood me. Voice Reconition was deemed impossible by the scientists and tech's of the day, I used to catch every tech publication, radio/tv show etc. I heard it a thousand times "talking and understanding language is something that computers only do in science fiction".
In other words, shows like Star Trek, Knight Rider and 2001 were predicting what science at the time deemed undoable, and less than 10 years there-after their fantasies were starting to come true. Remember those old voice-command systems in the win3.1 days, when only the rich and famous even had sound-cards or cd-roms ?
"Semper in excretum set alta variant"
"Dark Matter" is of course the name given to some substance that has mass, but neither absorbs nor reflects light. According to many calculations, the visible universe should weigh much more than what we can account for with telescopes.
This theory stated that "Dark Matter" may be a manifestation of mass sitting outside of our three (four?)-dimensional universe, undetectable to all of our instrumentation. The idea is that the gravitron is the only subatomic particle that's capable of jumping through dimensions, and therefore makes its presence felt even though we can't find any mass to associate with it.
All this is way beyond me.
Wah!
After reading the article I have a question. If there are multiple "walls" connected only by gravity, then why is it that we don't see the effects in our "wall" from any of the other "walls"? And vice versa, what will happen in the other "walls" when they use a particle accelerator to create mini black holes?
I've used the term walls several times, I'm referring to the dimension; groups that the articles refer to e.g. x,y,z,t (or space-time).
What do you mean 'Linux in a nut shell', it don't fit.
Well I'm glad I'm not alone in this one... I was thinking similar things as I read the article. My physics is limited to a couple intro courses at college, but I was thinking the same things with both the examples you brought up.
I pawned it off as the person writing the article had no physics background, or maybe I didn't have enough of a background in physics. Hell, milimeter is a 1-D concept, maybe there is someway to put a measurement on dimensions (of the existance kind). On the other hand, maybe it was the scientist trying to put it in lay person terms for whoever was writing the article. Who knows? Maybe we need to get a copy of the article that appears in Scientific American.
-- A computer without COBOL and Fortran is like a piece of chocolate cake without ketchup and mustard
Einstein's Riddle
"98% of the population cannot solve this riddle." - Albert Einstein
There are 5 houses in 5 different colors.
In each house lives a person with a different nationality.
The 5 owners drink a certain type of beverage, smoke a certain brand of cigar, and keep a certain pet.
No owners have the same pet, smoke the same brand of cigar or drink the same beverage.
The question is "Who owns the fish?"
Clues:
LOAD "SIG",8,1
LOADING...
READY.
RUN
thank you
Duh! I should have known you were trolling - all your posts were full of nonsense but I just had to reply. Oh well, I guess I will be more careful next time.
Couldn't you have used "Overrated?"
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Where does he live? :)
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This would explain why I have only one sock out of a pair. The other one is in another dimension.
> It is just as absurd as saying that 1 gram is
> more than 1 coulomb.
1 C weighs 5.69ng. Therefore 1 gram IS more than 1 C. Ha, ha.
Ryan
at the small scale, gravity is completely irrelevant compared to the other forces.
Scale is relevant. How do you define what is small and what isn't?
Electrons are smaller than the earth. They are not small. There may be other particles even smaller, which actually cause electromagnetism and gravity. Then you may find that these subparticles which cause electromagnetism have a much higher concentration than those which cause gravity.
The point is that it is not meaningful (and very inaccurate) to say that gravity is weaker as a force. You can only say that it has a smaller influence when dealing with objects of a certain scale.
I can't see the point in that, or is Emmett diluted perhaps? or having propaganation problems?
Well, so the question changes from "why is gravity so much weaker" to "why are the electromagnetic, strong and weak atomic charges (if present at all) so much greater than the gravitational ones in all particles known to human science?
Same difference.
The illegal we do immediately. The unconstitutional takes a little longer.
--Henry Kissinger
Laine Walker-Avina
LaineW@technologist.com
"In
The one potential flaw in this argument is that if gravity is pandimensional, why wouldn't electromagnetic forces be as well. which would result in two things if true:
1) gravity is still weaker
2) EM forces can be even stronger than we could possibly imagine.
also did the paragraph about creating black holes give anyone else the willies? that just seems like a Bad Idea.
Holy shit dude you are right on. There is not one advertisment on/in any form of media that thoroughly pisses me off more than that commericial. It doesn't help either that pepsi chose the f*cking ugliest girl amaginable to head there multimillion dollar advertising compaign. I mean you can't even understand how irate I become when everything stops and elephant girl says "Well, duh." oh my God. I have sworn off pepsi for the duration of my life becuase of this commercial, and the thought that there are people out there that would approve and further more ejoy this commercial is quite disturbing. God I hate that girl and all pepsi commercials! I would be the first to volunteer her as a lab rat for interdemtional travel....well maybe not, I don't want her representing my species. Her death at my hands would satisfy me however.
***Yeah, I'm the Million Dollar Man.*** You shot who in the what now?
Because we had the same question on our coffee machine, and it took me about 1 hour to figure it out.
I'm not bragging at all, I'm just saying that I don't think that this riddle is hard.
Yes, I have read the THEORIES....
and that is EXACTLY what they are, THEORIES!!!
I am not saying they are wrong, but you must admit
that as a THEORY, it has some chance of being
incorrect yes????
That is in essence what a THEORY is, an idea of what can best describe what we see or will see as a result.
As for them not creating black holes, I think you are mistaken. The physicists WILL say "hey, if we run up to X GeV we might get a black hole's signature" now THEY may not expect to create a STABLE long lasting black hole, but consider this: for a very long time scientists thought there was no way for elements much higher than the "normal" end of the periodic chart to exist beyond a few milliseconds, if that.
Well surprise surprise they have now found an "island of stability" much higher in the
periodic chart.... While these elements do not last as long as normal elements they last MUCH longer than science thought they could...
Suppose for just a SECOND that PREVAILING theory
is wrong. As a scientist looking at a theory, is not one SUPPOSED to have that element of doubt?
They are in essence playing poker with the fate
of the human race.
Would you advocate above ground nuclear tests in this day and age? I think not, because we now KNOW about the radiation dangers...
What about work on diseases like the ebola virus?
would you want researchers working on this in a
open air environment, or a level 4 containment
facility?
All I am saying is perhaps we may want to QUESTION
the idea before some idiot uncorks the DJINNI eh?
Service guarantees Citizenship! Questions Guarantee GITMO.... Amerika Uber Alles!
Dose gravity have a speed? Dose any force have a speed? What is a force? My head hurts...
We can laugh, but there are a lot of people who ask this question seriously every time physicists push the envelope a bit further. (Last time I checked we didn't collapse into a Bose-Einstein Condensate or become a strange(r) planet.)
For people who are worried about micro black holes, remember two compensating factors:
<ul>
<li>Hawking radiation should quickly evaporate it
<li>Even if it doesn't, this black hole would be so small that the earth would look as empty as interstellar space to it. It would quietly orbit within the earth and very, very, very, very rarely hit a proton (or quark?!) head-on.
</ul>
David Brin (astrophysicist by training) discussed this in _Earth_. I don't recall the mass of a black hole which could ultimately consume the earth, but it's a lot heavier than you would expect - equivalent to small mountains (or larger!)
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
There was a quote somehwere along the lines of "given enternity, type-writers and a room full of monkeys [that are either eternal or constantly replaced], they can produce the complete works of Shakespear; The law of probility dictates this."
Yes there are a lot of scientific background in Sci-Fi, but given the amount of Sci-fi that people comes up with, and the amount that actually comes true, and our ability to "stretch things" that doesn't fit exactly but have resemblence, we are no different from a room-full of monkeys! (yes, I'm stretching that too...)
Anyway, I'm terrible at Physics, and all this string theory 'n what not was talked about by Steven Hawkings at Kipp Thorn's 70th bday celebration a little over a month ago on my campus, of course I was too ignorant to go and left the opportunity to someone else who might understand better. Anyway, my point being, it's annoying to see people peckering at articles that tries to use analogies for the mass audience while they know probably less about the topic than the author of the article! (yeah, I guess this is flame bait, but after so many posts, I don't think more than 1 or 2 person will actually read this)
We had this as a lunch time puzzle at work one day. I won a free lunch because I was the first one to get it. :)
Time does not have a definite starting point. There are theories which claim that, but that is as far as it goes.
I agree. How can you prove that time had a starting point? That's like trying to prove how the world began.
And frankly, that may not even be in the realm of science.
I need a TiVo for my car. Pause live traffic now.
I doubt there's any way even for an "outside observer" to tell if we're "in the centre of it", as opposed to the "first three or last three" dimensions. Why do I say this? Well, every dimension is supposedly orthogonal to each other (neglecting curvature), so who's to say there's any real "ordering" of the dimensions anyway? I agree, it's a matter of perspective. Scientists will likely consider us to be "in the center of it" - whatever that means in terms of multiple dimensional analysis - unless and until some genius comes up with an argument that some other view makes the math simpler.
Zahlman Q. Namlhaz, esq. {:> "Zahl Incorporated - the Last Word in Everything(TM)"
Who says our normally observable dimensions are strengthening gravity, though? Does the theory predict weaker gravity in a 1- or 2-dimensional universe?
Zahlman Q. Namlhaz, esq. {:> "Zahl Incorporated - the Last Word in Everything(TM)"
>Ehm, excuse me but doesn't the phrase "comparing apples to oranges" come to mind here? I mean how the hell can you compare two forces with completely causes? It is just as absurd as saying that 1 gram is more than 1 coulomb. Gravity is related to mass, and electromagnetic forces on charge. How can someone compare the mass of the earth with the charge in the atoms in a magnet? They are totally different things
Gravitation coupling constant = 2piKM^2/hc = 5.3*10^-38.
electromagnetic = e^2/2hc = alpha = 1/137
weak = G_F8piM^2c/h^3 = 1.02 * 10^-5 (even though weak and electro are the same thing)
strong = alpha_s =~ 1
Hence gravitation is extremely weak
Also, they are all charges, just difference kinds of charges, gravitation is carried by the graviton, and is the gravitational charge, strong is the colour charge, weak is the weak charge, and electro is the electric charge -- they are all analagous.
>Dimensions do not have a size. Objects have sizes in a set of dimensions.
Since I am only a 3rd year uni student, I cant comment much on on this, but I know the article is correct however.
OK, I'm not that good ath physics, but isn't e=mc^2, that is, mass is energy. And charge (Or more precisely, difference in charge) is energy too. So it should be pretty easy to compare them. Or where is my error?
--The knowledge that you are an idiot, is what distinguishes you from one.
--The knowledge that you are an idiot, is what distinguishes you from one.
I agree. But the article does not mention the charge of the earth, the magnet, nor the pin. They are relying solely on the reader's perception of things as "big" and "small" to illustrate a point that happens to be true for other reasons.
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Leptons and quarks are fundamental particles. The earth is not a fundamental particle.
I would very cautious before making such statements: at best it makes you look very short sighted.
A few decades ago people thought protons and neutrons were fundamental particles. A century ago people thought atoms were fundamental particles.
This is why I made the analogy between the earth and a proton: there is no fundamental difference between them.
Why dont we see a 1/dist^7 relation to distance if there are 7 dimensions. This is what they are saying. If there were more dimensions we would see another power. but we don't see this.
could somebody explain.
Refresh my chemistry and physics, what are Leptons and quarks?
Sorry, its been a few years
I think we've pretty much beaten to death the idea that this is just superstring theory reproduced yet again. Personally I don't buy it, and one reason for this was something I saw on slashdot a while back. If you go here: http://www.npl.washington.edu/AV/altvw100.html you can read a competing version of general relativity that implys that there are no such thing as black holes, a theory I'd have to say I support at this point. This would be important in this discussion since all of the recent progress in superstring thoery is based on a supposed duality between perhaps nonexistant black holes and these strings.
If anything is disurbing is that you would use a commercial to decide anything related to product purchasing. Heck, even more disturbing is your hatred of something on the television, to the point of murderous thoughts.
Okay, I've got my asbestos on, so flame away.
Here's what I think is really going on. Gravity isn't us being pulled toward the earth, it's us being pushed towards it. Why do I think this? The Zero Point Energy field. It's everywhere. Einstein always said there was more than enough energy in the space occupied by a coffee cup to vaporize all of Earth's oceans. He wasn't talking about the strong nuclear force, you know, the one that makes the wonders of atomic weapons possible. No, he was talking about the energy inherent in space-time itself. It's everywhere -- not only in pure vacuum, through which it constantly streams unobstructed, but also both inside and outside every object, every atom, every *thing* that exists. It's what keeps the negatively-charged electrons orbiting an atom's nucleus instead of spiraling right down into it, attracted there by the positively-charged proton. Because it's everywhere, it exerts a force in every direction. This force extends outward without bound, its strength decreasing with distance. It also interacts with matter, which "blocks" it somewhat. And what happens when a force meets resistance? It tends to push that resistance in the same direction as its force vector; at the same time, some of its energy is consumed by the work it does (moving the matter it hit). But what happens when this force is pushing on an object from *every* direction at once? You might think it'd crush it. Nope. Remember; to be crushed, there would have to be a "pressure" or force differential between the object's inside and outside and, as explained previously, the force is equally pressing from both within and without the object. This is analogous to our own very observable situation on earth. We exist under a rather thick layer of atmosphere. Right now, there are millions, if not billions, of tons of force pressing down on your head from the weight of the air above you. Why aren't you crushed under all that weight? Because there's an equal force balancing it from the opposite side. (Just trust me on this one.) Same thing with the ZPE field.
So here we have this great big giant ball of matter we lovingly refer to as "Earth." It, being made of matter, presents resistance against the force of the ZPE field, and it dissipates some of that force before it gets all the way through the earth to the other side. Now, because all the energy coming from every side of the earth interacts with the earth's matter in the same way, with resistance, it doesn't push the earth in any one direction -- just like the air above your head doesn't push you right into the ground. But think now of something sitting ON the earth, something that can be considered part of its matter. Something like you, sitting there at your computer. You too have ZPE energy coming at you from all sides; up, down, inside, outside, left, right, etc. But because the earth, in interacting with it, is shielding some of that energy by absorption during its travel through the earth (some comes from beyond the other side of the earth from you, some comes from 12 feet under your chair, some comes from .001 millimeters under your butt sitting on the chair, etc, but all of it is absorbed in some way by passing through matter), there is NOT a net zero ZPE force acting upon you. There is in fact more of it pushing you down from the relatively unshielded "Up" direction than there is from the highly shielded "Down" direction; therefore, you are pushed down towards the center of the earth, and the force with which you are pushed is in direct correlation to your mass and the earth's mass. Does that sound familiar? :)
Now think of a black hole. Eerie, scary things. They are of course extremely dense collections of matter, where even the electrons can't orbit because it has been crushed so competely. In ordinary matter, there is LOTS of empty space; a neutrino could pass all the way from your forehead to the sole of your right foot without even touching any of the matter that makes you up. That's why only a very very small percentage of the ZPE energy interacts with you in a direction that isn't balanced from the other side (ie, through the earth) -- because there's very little there to interact WITH. But what about a black hole? Very very dense, trillions of trillions of trillions of trillions of trillions of tons of matter all smashed into a tiny ball -- there isn't ANY free space inside it; it's all matter. So what does that mean? Yep; ALL the ZPE energy gets absorbed by interacting with it, from every direction, and so the energy flowing from behind you, through you, and towards the black hole isn't balanced by anything pushing back FROM the black hole -- and you are completely crushed into it.
This is also why there is such a thing as the Gravitational Constant. It refers to the amount of interaction between the ZPE energy force and matter. It is very very small, and is multiplied by the mass of two objects to determine the amount of gravitational attraction between them (the GxM1xM2/d^2 formula). That number, "G", is literally how much of the energy in the ZPE field gets absorbed by passing through one kilogram of matter. Let's get into a bit of math here...
The gravitational force, in Newtons, between objects having masses of M1 and M2, in kilograms, and separated by a distance of d, in meters, is the product of the two masses divided by the square of the distance between them... multiplied by G, which is 6.673e-11 Newton-meters squared per kilogram squared (the odd units associated with G are there so they cancel out all the units in the formula other than the result, which is in Newtons). Two 1-kg objects separated by 1 meter would yield Gx1x1/1x1 Newtons, or 6.673e-11 Newtons. Not very much. This means that most of the ZPE energy passes through these objects unobstructed. But how much doesn't? Literally, "G" doesn't... thus, 0.000000006673% of the energy gets absorbed and translated into "motion" by pushing the matter in the direction in which it is imbalanced. I may have said it before, but it's worth repeating: Nature doesn't abhor a vacuum. Nature abhors imbalance. All things will seek balance. That's how you can siphon gas out of your gas tank, and that's why you get pushed to the earth.
Let's take a more realistic example: you and the earth. You have a mass of, let's say, 80 kg (176 pounds); the earth's mass is 5.974e24 kg (rather a lot of pounds). The distance from you to the earth isn't 0, as you might think; it's the distance from your center of mass to the earth's center of mass, which is roughly 3,185,500 meters. So plugging all that crap into the formula, we get 4.71e+13 * G, which makes 3,142.83 Newtons of force pushing you to the earth. G is the percentage of "gravitational" energy that gets absorbed or deflected by its interaction with the matter making up you and your body.
I haven't completely worked out ALL the math yet, but something tells me this is right. It answers all the unknown things about gravity, it explains momentum and inertia, it explains what keeps atoms from just collapsing into themselves... hell, it might even be the definition OF matter. So come on; let's see you armchair physicists blow some holes in my theory...
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It can't possibly "propagate at c^2" because the units would be wrong. Propagation is how fast the effect goes from being felt at A to being felt at B, so it has units of m/s, just like c. Squaring a quantity squares its units too.
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I have been watching sci-fi shows and movies for a number of years about parallel dimensions, during that time you tend to develop your own theories about 4th dimensions.
From what I have gathered, for every choice we make there is an infinite amount of possibilities and from those possibilities an inifinite amount of alternate universes are created. Each universe is unique. And the theroy of a paradox, a loop error (example: I go back in time and kill my mother before I was born, I was never born, but then how could I have killed my mother...endless loop), is in fact only half true. If you make a change in the past you begin to exist in an alternate reality and you would continue on. (Reference in Back to the Universe: "...it would destroy the entire universe, however it would probably be limited to our own galaxy"....almost true; you'd never return to that universe (but it would continue on as normal without your existence.)
Now getting back to the gravity theory. If in fact gravity is a constant and you could effect changes in one universe and affect anothers, then it would make the above theory false. There would have to be a universe that would not be affected by the action of creating that change. It'd be as if you created a paradox in every other universe (affected some change that should not have happened because they did not do it).
I believe this gravity theory to be false
"Imagination is the only weapon in the war against reality." -Jules de Gautier
From a Newtonian perspective Gravity acts instantly. If the Earth needed to wait 8 minutes for the suns gravity to hold it in orbit we would spin off out of the galaxy. A physician named Laplace postulated this in 1825.
I would imagine that the best place to measure the propagation of gravity would be in an event such as a supernova. There are tremendous energy to mass conversions that would effect the gravity between the supernova and an observer on Earth. If Gravity propagates instantly you would get a different event observed on Earth than if gravity is limited by the speed of light and a "gravity wave" traveling at the speed of light is unable to overtake and slow down or blue shift the radiation traveling towards Earth from the supernova. When you ask what is the speed of gravity is from this perspective you are really asking how accurate is your stopwatch.
Physics according to Einstein uses the speed of light as a limit to gravity propagation non locally. The relativistic calculations work for many applications, but they are not very easy to use for doing things like calculating satellite orbits.
I guess it all depends on what you want to do with a calculation. When I go to a restaurant and need to calculate a tip it is easier for me to move the decimal point in my mind than try to do it out on paper. I have friends that make their children do it out longhand on paper for the practice.
Yep
LOAD "SIG",8,1
LOADING...
READY.
RUN
Hyperspatially Orthogonal Transmission of Gravitational Rays In Twisted Space, or HOTGRITS for short...
Damn...I think I've just used up my day's supply of long words...
-- Bah weep grah nah weep nini bong
Definitely not right.
Never confuse equality of quantity with equality of property. Example: A dollar buys me two dollars. However, apples are not the same thing as dollars. Apples are tender, dollars are legal tender. Apples are round, dollars are rectangular and flat.
Conversion may occur under some limited conditions, as well.
For example, I may not transform an electron directly into energy. You gasp! No, I'm not kidding. I have to have an electron and a positron to do that. Nor can I convert a photon into just an electron.
Saying that "mass=energy" and "charge=energy" ignores all kinds of basics, like conservation of baryon number, conservation of lepton number, conservation of charge, etc.
Matter and energy are not the same two things. You may exchange one for another, under limitations, but don't think that they are in any way identical.
As they mentioned in the article, all the forces in nature are tied together somehow, except for gravity. If you assume that gravity is in fact connected to the other forces but there's just no good explanation, then the comparison is valid. Since they are looking for this explanation/connection, they probably assume that it exists and so there's nothing wrong with them making comparisons, preliminary as they may be. But, hey, don't take my (or their) word for it. If you have any doubts, jump off a tall building. Gravity will accelerate you for at least a few dozen meters (if you pick a good building) and yet the forces that hold the concrete together will decelerate (accelerate in the opposite direction, against gravity) you over a distance of a few millimeters.
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Even as you read this, your pants are strangling your loins! Aaa!
I have no grounding physics whatsoever but the assertion that gravity is weak because it takes the entire earth to hold onto a pin seems odd to me. The earth is holding back millions of pins plus everthing else as well. It also doesn't seem to get any weaker however many things you put on the earth, or indeed how "heavy" they are. It even seems to be able to hold the moon in place too! In fact, it seems to me that it could hold lots of moons in place.
I am missing something terribly obvious to everyone else?
Regards
Yep.. put it in the same category as bible codes and conspiracy theories that invovle the number of letters in presidential assassin's names.
Introduce enough unknowns (particularly ones that involve infinity) and you can prove about anything.
How we know is more important than what we know.
All this thought about folded space and parallel worlds makes me wonder. Could there be something larger that our galaxies are evolving out of? Maybe theres this whole space-time matrix, i know it sounds very sci-fi but if you look at the maps they currently have of the universe you see a pattern where theres all these strings of galaxies like mountain ranges and huge voids of nearly empty (as far as we know) space between them. Could this be like the ocean where there are huge empty areas and islands strung across the planet in stretches? But if you think about it islands are really just mountains on the ocean floor reaching the surface. Perhaps theres some huge multidimensional surface beneath us we just dont happen to see it because we're on the top just as it tooks plate techtonics and ocean floor mapping to truely understand the geology of islands and their creation.
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Who's with me?
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Dimensions do not have a size.
Don't confuse math and physics.
There is nothing in the physical world that definitively suggests that dimensions are infinite. However, we use mathematical models to describe this physical world which usually are open-ended. After all, there is often no point in introducing a model which is more limited than the real thing.
That said, models such as an S2 (a two-sphere) which ship navigators would describe using only longitude and latitude (since ships as a matter of normal operation wouldn't have useful altitude from sea level) can have size. Imagine squeezing the earth down so that a great circle about the equator was only a 1m circumference but a great circle about the poles was 10,000 Km. You could use measurements within that space to determine that one dimension had a longer transit (time to return to origin) than another. It would be 'bigger' than the other, though you could not reach the end of either, since you'd constantly be retracing locations.
The size of a S2 universe could be infinite if you imagine it expanding like a balloon. But it could be mixed, where some dimensions expand, and others contract. So a S2 universe which was spherical at creation could mature (that is, change according to a linear dimension R - time - so we'd call it RxS2) whereby the equator contracts and the poles expand. The equator could contract to such an extent that the universe begins to resemble a S1 - a circle, where you would travel up the meridian and down the date line, but a 'left turn' would bring you to your current location so quickly that you wouldn't notice. (It's a bit more complicated than that, but you get the idea) There'd be no visible concept of latitude, only longitude.
So classically we wouldn't measure latitude because it'd be so small, however it is still there. Now consider that subatomic particles, who are more sensitive to small numbers, would seem to behave strangely because in measuring them, latitude would have a big effect. Particles would seemingly blink in and out of existance as they crossed your line of longitude if they moved along a line of latitude. They might appear to wiggle, or vibrate. They would be hard to measure because there'd be this uncertain measurement, latitude, which we've never dealt with before. Their velocity would be strange in the same way. Forces that drop off over distance would still be affected by the latitude measurement whether we recognize it or not.
This general theory has been around for a rather long time, but the specifics have never really been nailed down. Typically we deal with models that are well behaved: S1, S3, S7, etc. S2 is not well behaved because our mapping breaks at the poles (when you are at the north pole you are at 90 degrees N latitude and at every longitude, which is a problem...) S1 (a circle) is well behaved because there is a 1-1 mapping between actual locations and coordinates. S2 maps the north pole to an infinite number of coordinates.
Scientists have looked at universes with 10 and 11 dimensions, where one is linear (time), 3 are expanding and provide our spacial measurements, and the remainder are contracting and provide for the hodge-podge of forces and interactions that we see.
The article was interesting and the idea
may hold promise. BUT.........
Did anyone notice the little BLURB in the real
article?
http://unisci.com/stories/20003/0718001.htm
"Moreover, if the force of gravity increases dramatically at short distances, it may be possible for the next generation of accelerators -- such as Europe's Large Hadron Collider scheduled to begin operation in 2005 -- to create BLACK HOLES, regions smaller than the radius of the extra dimensions where gravity is so strong that nothing can escape.
Since small black holes quickly evaporate by Hawking radiation (orphaned members of pairsm of virtual particles whose partners are swallowed by the hole, and which carry off some of the hole's mass), this low-energy radiation from a high-energy collision would be an unmistakable signal that a black hole had been created."
So whaddya wanna bet these guys are gonna try and make a black hole or two????
And yes they MAY be safe, but what if they are wrong hmmmmm??? Anyone else feel kinda sketchy about a man made black hole fuck-up?????
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Actually this is a perfectly sensible and serious theory, which has been around for 10 or 15 years, in various guises, it has just suffered from abbrevation and simplification.
Regarding the comparisons, if you take any fundamental particle in the universe which actually has both mass and charge and place an identical particle at rest 1m away from it, the electrostatic force between them exceeds the gravitational by many orders of magnitude. If you want a theory that explains both electromagnetism and gravity as aspects of the same thing (which is generally considered desirable) then it has to explain this huge discrepancy.
Regarding the dimensions, imagine a 1mm^2 two-dimensional creature living on the outer surface of a garden hose. It has two very different dimensions: along, which is practically infinite (althoiugh explorers may claim to have reached the mythical "tap" and "spout") and around, in which you can go only a few dozen body-lengths before you get back to your starting point.
Actually an even closer analogy would be to imagine creatures living on the hose big enough to actually wrap round it in places. Fundamental particles are supposed to be entangled with the extra dimensions in this way.
The strong nuclear force is given credit for holding the nucleus together. It doesn't affect our everyday lives because it is short range (about 10^-15m) and it doesn't effect leptons or photons. (Leptons are electrons and a few other particles like neutrinos that you won't see unless you look for them, or make them in particle accelerators.)
- W. Blaine Dowler
http://www.bureau42.com
IIRC you set c=1, h-bar=1 and G=1 in natural units - it makes equations a hell of a lot simpler since you don't need to deal with conversion factors for units.
>Would this then account for the internal forces in an atom keeping the positrons together? Last I heard we still weren't sure what was causing it, but if the force of gravity increases dramatically at very small distances from the source...? (IANATP - I Am Not A Theoretical Physicist)
Do you mean protons within the nucleus? That is the strong force, carried by the 'gluons', which have been around for quite some time now, cant exactly remember how long though.
The nuclear binding can then be nicely explained, and gravitation is certainly not the cause of that.
Because G is small.
:-) I'd like to know why G constant is the way it is.. what does it stand for? The number of angels who can dance of the head of a pin? The number of massless spin 2 bosons which can fit into a 3x3 room which has a 2.5 people in it?
The equation for measuring the gravitation force between two objects is the same as the equation for measuring the electromagnetic force between two objects, except for the constant.
If you want to figure out why gravity is weak, figure out why G is small. There are a lot of "magic numbers" used in physics that were measured through experimentation, but which have no explanation. As a programmer, I find the situation intollerable
Once we know where the magic numbers come from, we'll have a better chance of understand how things work on the lowest (i.e.: quantum) levels where they likely originate.
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Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
Here:
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http://www.alexchiu.com/spacestation/grav1.htm
Peter
Most "strong" interactions are measured upon contact or in the levels and quanta of an atom's electron cloud.
Electromagnetism is one of these that at least radiates to a distance similar to gravity... and thus a radio wave can be heard on the other side of the planet and beyond. Yet even EM doesn't match gravity's uniquely far reaching ability to bend space and time.
If Newton's equation is taken at face value, without factoring in theories of how gravity may be quantitized, then the sense of scope is amazing:
Makes you feel empowered, doesn't it?Took me about 30 minutes or so. Pretty sad if 98% of people can't do it.
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Somebody else posted a cool link, but I don't have moderator points to bump it up. I do, however have karma to burn, so here it is.
Maybe you +5 posters should learn some physics. You can compare the effect of gravity to the effect of electrostatics on electrons, for instance, and electrostatics is [e^2/(4*pi*e0)]/[Gm^2] times stronger than gravity
The other reason we (as humans) don't directly feel the strong and weak forces is because they have limited range, being carried by particles with mass. EM is carried by massless particles and therefore has an infinite range. Gravitons are postulated to be massless as well.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
If you have to ask you just wouldn't understand;) Perhaps a future article will explain;)
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10 spatial dimensions, and the math is quite complicated. These are used in GUT which attempt to explain electro-weak, strong, and gravitational forces in a single, unified theory, and the differences arrive from symetry breaking at conventional energies. However, at very large energies, like the first 10^30s after the big bang, they were all 1 force. It is speculated that as the universe changes, the laws of physics as we percieve them may change, but it's that for now, speculation.
Gravity IS the weakest of all known forces of nature. If you compare the force of gravity to the other forces: weak&strong nuclear force and electro-magnetic force, than gravity is far far behind.
The fact gravity is felt strong to us is just because any other force is balanced on large scale, and thus we feel only "residual" force. There are positive and negative electric charges, whereas the strong nuclear force is created by three-color quarks that balance each other.
Anyone with a good scientific background can see that this article is very flawed. Here are some examples:
Although we think of gravity as strong -- we can get hurt if we fall down -- compared to electromagnetism, gravity is astonishingly weak. It takes the gravity of the whole Earth to hold a pin on a tabletop; a toy magnet can lift it easily.
Ehm, excuse me but doesn't the phrase "comparing apples to oranges" come to mind here? I mean how the hell can you compare two forces with completely causes? It is just as absurd as saying that 1 gram is more than 1 coulomb.
Gravity is related to mass, and electromagnetic forces on charge. How can someone compare the mass of the earth with the charge in the atoms in a magnet? They are totally different things.
The notion sounds deceptively simple: besides the familiar three dimensions of space there may be other dimensions, too small to see yet perhaps as large as a millimeter.
Dimensions do not have a size. Objects have sizes in a set of dimensions.
I hope Sla
I wonder if this new theory was derived from the one about the curvature of space giving rise to dimentions...It seems to me that this could be the reason for the nano-sized dimentions...gravity could be "curling" space into itself creating spacial eddys for matter and light to be trapped
Does this mean that we will be able to build gravity bombs so we can preemptively defend ourselves from invasion from those other dimensions? "Let's 'grav' those suckers before they decide to come over here and take our stuff."
This is starting to sound too much like the Seth books. In one of the books (don't remember which one) he claims matter is time-shared between dimensions. So we get our little time slice, then we are suspended and some other dimension gets a chance to "run". (He didn't mention what happens if our swap space gets corrupted though.)
When I was reading through some topology book when I was in high school it seemed to make perfect sense to me that if folds of the universe were sufficiently "close" to each other (perhaps even *overlapping) that they could have some sort of interaction. In fact, this is what wormholes are (supposed to be).
Just imagine a tablecloth on a table. Now ruffle it up. The surface of the tablecloth is actually a three dimensional world. If you trace your finger accross the surface you are travelling in space. But what if you could "jump" through a ruffle, from the upslope of the ruffle to it's downslope (or vice versa). What if a magnet on one side of the ruffle attracted a piece of metal on the other side "through" the tablecloth. That is sort of what this theory is saying. Close folds are having a dampening affect on the local gravity. The best theories are the ones that just "make sense" in retrospect.
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Could this explain why our universe is expanding or moving apart? Say, for example, that we were in one of those small dimensions and the gravity from this dimension was propagating across and acting on our universe, wouldn't that pull it apart?
Also, if we can learn how to manipulate gravity, could this allow cross-dimensional communications? I also read that gravity propagates at c^2, this would be excellent for interstellar communications.
Of course I'm most likely talking out my ass. Damn, I wish I had taken particle physics courses in college. Time to buy some books I guess.
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Don't they know that it isn't the multiple dimemensions that make gravity weak. It is the presence of the other dimensions that are causing gravity to begin with.
It is quite an interesting article. However it shows an all-time stereotype that we are some sort of center. It seems that Relativity teached absolutely nothing to a bunch of monkeys that just came out of the trees.
What if this, "our" Universe is just a projection of much larger structures? No we are not looking through 3-4 dimensions over two or five or seven more. We could be folded in three dimensions that result from something much larger and bigger. Or "our" Universe could be the result of the intersection of two or more "meta-Universes".
You may argue quite strongly with this. Well I'm not pointing how the Universe is made. I'm pointing on how we look at the Universe. Imagine that our Universe is made of five dimensions. What tells you that you are "in the center of it"???? You could well be in the first three or last three. The two other you don't see, feel, taste. As much as what you see is just a 0,01% of what sorrounds you. Besides you see nothing. All what you "see" is the result of how your eyes and brain produce out of something beyond you. Forget about radio waves, infra-red, ultra-violet, X-rays, your sunglasses and your short-sightness and you can still say "I see the world" with the same success.
When one talks about "other dimensions" should be very careful. Because it will be quite serious the problem on how we are positioned to them. I would wildly laugh if suddenly anyone found the "originator" of gravity in the dimension next to us. No one knows how exactly gravity is made of. And G is, until the biggest mistery of all. I consider that this article fails in this little thing. It considers gravity as "weakening" through dimensions. Could it be that gravity is born from "travelling" through them? We are talking about dimensions. This is not a thing that stays next door. It is in every quantum of our Universe. a dimension determines a section of the space. And we live in it.
PS: Again about relativity. For the hard-thinkers. What is the correct theory: geocentrism or heliocentrism. Note: both are correct. The problem is that it is much simpler to calculate planet dynamics from a heliocentristic point of view. However if you are hard in maths we can do this from a geocentristic point of view. The problem is that you have to do a lot more of maths to achieve this. And be quite careful about forces and gravity. However it is done. Many observational tasks are made from a goecentristic point of view. Middle Age geocentrism failed because it ignored completely Dynamics and mixed everything in a mystical-religious-political pan. However you still can say with some success that you are in the center of the Universe. The problem is that you have to be a damn mathematician to do it...
is the relation you're looking for. However since these dimensions aren't large-scale but are curled up, this relation will be different due to the topological differences between a (relatively) flat surface and a curled up tube.
Correct me if I'm wrong but isn't the sole premise of quantum string theory that there are 9 (or something) dimensions? The extra dimensions were brought in just to make the math easier I beleive and string theory is generally shunned by quantum theorists as a bit of mathematical magic.
How we know is more important than what we know.
If the Universe isn't infinitely large, what's beyond it?
If gravity spans dimensions do black holes dump their loads into our inter-dimensional neighbor's yards?
I am a Goddamn Cosmic Miracle!
Thank you for taking the time to explain this so well. I appreciate it even though the idea of a distributed force as you describe makes me realise just how little I know about the subject!
Regards