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Simulations Back Up Theory That Universe Is a Hologram
ananyo writes "A team of physicists has provided some of the clearest evidence yet that our Universe could be just one big projection. In 1997, theoretical physicist Juan Maldacena proposed that an audacious model of the Universe in which gravity arises from infinitesimally thin, vibrating strings could be reinterpreted in terms of well-established physics. The mathematically intricate world of strings, which exist in nine dimensions of space plus one of time, would be merely a hologram: the real action would play out in a simpler, flatter cosmos where there is no gravity. Maldacena's idea thrilled physicists because it offered a way to put the popular but still unproven theory of strings on solid footing — and because it solved apparent inconsistencies between quantum physics and Einstein's theory of gravity. It provided physicists with a mathematical Rosetta stone, a 'duality', that allowed them to translate back and forth between the two languages, and solve problems in one model that seemed intractable in the other and vice versa. But although the validity of Maldacena's ideas has pretty much been taken for granted ever since, a rigorous proof has been elusive. In two papers posted on the arXiv repository, Yoshifumi Hyakutake of Ibaraki University in Japan and his colleagues now provide, if not an actual proof, at least compelling evidence that Maldacena's conjecture is true."
The way I think of the universe, is like a 11 dimensional sphere of putty, that got hit with a hammer. (aka the big bang).
So, the sphere got deformed spraying outward in 3 dimensions (space) while flying off into a 4th (time) and the other 7 dimensions got compressed.
A Particle is a bit of energy caught in a loop around some number of those 7 dimensions, each combination of possible wrapping gives a different fundamental particle, with antiparticles having the same wrap, but opposing spin.
Light/radio 'waves' are caused by the photons looping around one of the higher dimensions, not one of our 3 spatial dimensions, which is how it is travelling in a straight line space, yet still taking a wavering path; like a piece of string wrapped around an infinitesimally small cylinder.
But that's just my mental model, it work well enough to keep me from going mad (I think)
A very crude analogy would be a Fourier transform. If you take a simple wave it is very complicated to describe it in time domain (lots of terms mathematically), but it has a simple mathematical expression in frequency domain with just a single term.
The physicists have figured out how to simplify the maths. This transformation also has a physical interpretation which is best explained as a hologram. A hologram has information from 3 dimensions scrunched into 2 dimensions, ie when you look at a hologram, it appears to have depth. In a common hologram sticker, that information is encoded in polarization. In the same manner, they seem to say information in a 11 Dimensional world can be scrunched into lesser number of dimensions. Hence the analogy.
http://slashdot.org/submission/1062723/Cheap-mobile-data-plan?art_pos=2
One can manipulate math to to describe or answer pretty much anything you want. Just because the equations match what's happening does not mean they describe what's going on.
Who cares? As long as the equations match what's happening (and what's going to happen), does it matter what's "really" going on? We've been doing quantum mechanics for almost a century now, and still no one actually knows what it all means - but we're perfectly happy to take advantage of QM in our technology.
Yes, it really matters. In the middle ages, there were mathematical formulas which described the planets and sun revolving around the earth. The math worked very well even though the theory was proven to be very wrong.
Math, particularly when used as a language, can be used to describe all sorts of things. As with the spoken language, one can create a sentence that is technically and grammatically correct, but still is nonsense. The whole purpose of langauge, any language, even mathematics is to convey ideas. So, yes, it really does matter what's going on. That's the whole point of using a precision language, like math, in the first place.
I got into this discussion too late to be noticed, but I feel the need to help people understand that this theory is *NOT* stating the universe is a simulation. Projections are not simulations.
What the theory suggests is that of all the dimensions we know about (the article mentions 6, which is how many dimensions you get with one flavor of string theory), some of them are illusion. Like a hologram -- a 2D plastic or glass toy that displays a 3D image. The universe does not contain 6 dimensions; it contains a smaller number, and the rest of the dimensions only appear to be there.
It's likely that the universe contains at least three dimensions, because we would have noticed non-isomorphic behavior in space. But the jury is still out on whether the fourth dimension -- Time -- is an illusion. The same goes for the fifth and sixth dimensions.
None of this says anything about the universe being simulated. That's a philosophical question that physics will probably never be able to answer.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
What do you mean it was proven wrong? It never was, and it hasn't been yet. It probably can't be. (Well, except in the sense that Newtonian Mechanics was wrong.)
What was proven was that the heliocentric theory was a lot easier to calculate. And you didn't need to keep adding on as many special correction factors each time the instruments improved. So now we're doing relativity and quantum mechanics, and they are just means of calculation. Relativity doesn't really define an interpretation, and Quantum Mechanics is consistent with multiple different interpretations. The different interpretations seem quite different when described in English, but the math is exactly the same. You can't chose between the multi-world interpretation and Solipsism on the basis of evidence, you need to choose on the basis of philosophical biases.
Just consider, Relativity talks about bent spaces, but in what direction is space bent? Well, that's not clear. Perhaps saying bent is just something to enable you to understand that what we're really talking about is lengths being longer in one direction than in another, but that's just gibberish. You CAN'T translate Relativity into English and have it really make sense, any more than quantum mechanics. The last one you could "pretty much" do that with was Newtonian Mechanics, and if you really think carefully about that, you also find places where you must follow the math rather than reason. Just try to think carefully about what an infinitesimal means, or an imaginary number. You can't. You're just used to them, so you slide over the places where they are incomprehensible.
FWIW, I don't understand pre-Newtonian mechanics well enough, but I'm rather certain that they had equally incomprehensible places. Think of Cantor's proofs, and then try to imagine what it means to paint one copy of the interval of real number red and another blue. Or Zeno's paradoxes.
I think we've pushed this "anyone can grow up to be president" thing too far.
The fixation on "best" accepted theory is more about hubris than insight.
The Kolmogorov/Chaitin view is that you should believe every statement about the universe that you can't formally disprove—all at the same time— using an exponentially weighted average based on the minimum description length of each viable description (baroque theories with billions of epicycles are down-weighted by k^-1e9, where k is the mean entropy of your typical epicycle). I don't really know the math, so take that with a grain of salt, but it's at least the general idea.
The standard model is extremely cogent and concise. It will exponentially outweigh practically everything else.
The only reason this isn't used is that we pretty much never know the minimum description length for anything (there's a result where something akin to minimum description is length is formally proven to be the hardest computation definable), and we can't take the exponentially-weighted integral of all as-yet undisproven theories by any convenient method.
Any undisproven theory that comes along with the potential to be formulated as cogently (or nearly so) as the standard model should be regarded as valid until proven otherwise (either false, or irredeemably baroque).
There's no sane reason to impose incumbency politics on theory. Theory is not a vote.