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At Multiverse Impasse, a New Theory of Scale

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Re: At Multiverse Impasse, a New Theory of Scale

#81

Post by AtmaScout »

MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

Thanks for your post and link. I recently watched Particle Fever on Netflix and became extremely fascinated with the field. A lot of the information you posted is touched on in the documentary. It is mostly focused around CERN and the years leading up to the Higgs particle discovery. There are also great interviews with David Kaplan and Nima Arkani-Hamed.

You've likely seen it but if not you might enjoy it.

Re: At Multiverse Impasse, a New Theory of Scale

#82

Post by kazinator »

> "Multiverse ennui cannot last forever" says Graham Ross?

That is naive. There is no way to prove or disprove it; it can be safely regarded as true without ever contradicting any possible observation we can ever make.

I do not think physics will ever settle the questions in such a way that the "multiverse ennui" is not invoked to cover the loose ends; in fact, it will become more and more obvious as the inescapable conclusion.

The deeper we dig into nature, either we keep finding more mathematics, or we encounter some absolute that can no longer be analyzed.

Once we know every physical law, and are certain nothing more is to be discovered, how do we distinguish our universe from a set of mathematical axioms? We have two choices then: to suspect there is some outer universe which implements the rules and axioms of this one. Or else admit that axioms do not require an implementation: they just are, and that's what makes their system exist (which means that any other axioms and rules we can imagine also exist just as much).

Either hypothesis is an unprovable "cop out"; but the latter of the two is more plausible. The first hypothesis still leads to an infinity of universes, and they have to be nested in each other in an infinitely regressing sequence. The second one has no such silly requirement; and it has the anthropic principle which plausibly explains everything that seems arbitrary or special.

Re: At Multiverse Impasse, a New Theory of Scale

#83

Post by evanb »

MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

Do you have any rumors or specific knowledge (even if it's not something you'll share) regarding SUSY? They found missing energy? A new plethora of resonances? Higgsinos or sfermions? Something more exotic?

Re: At Multiverse Impasse, a New Theory of Scale

#84

Post by jwuphysics »

MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

I study astrophysics, so I won't be able to say much about SUSY or string theories or conformal field theories. I do agree that we're living in a golden age of physics! But your second and third points, inflation and SUSY-- those are definitely not confirmed. In fact, the primordial gravitational waves from BICEP2 are almost certainly dust contamination signal (e.g., http://arxiv.org/abs/1405.5857). The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Perhaps you know something that I don't!

Re: At Multiverse Impasse, a New Theory of Scale

#85

Post by mkaziz »

smokel wrote: post #72
axilmar wrote: post #45

Earlier quoted context omitted.

I do not think that it is possible. Any physical system that can be described by a set of mathematical laws is bound to have some axioms that simply cannot be proven within its context. Godel's incompleteness theorems prove that. Hence, we will never get to the bottom of the reality of our universe.

Your statement that we will never get to the bottom may be true, but the reasoning is flawed. Gödel's incompleteness theorems are about mathematical theories, not about physical theories. It may well be that for physical understanding a very limited arithmetic is sufficient. Also, there may be statements that are unprovable, but these might turn out to be irrelevant to sufficiently understanding the universe. Also, a…

Do you not have to start off with a set of axioms though? Assumptions that will never be proven?

Re: At Multiverse Impasse, a New Theory of Scale

#86

Post by mSparks »

calinet6 wrote: post #66
mSparks wrote: post #56

Earlier quoted context omitted.

But the whole point of the multi verse model is that universe also exists. Multi verse theory afaik is just a mathematical construct of the various dimensions we can observe in a space time framework. The whole http://en.m.wikipedia.org/wiki/Flatland Idea.

You're thinking of parallel or alternate universes, which is based on the "many worlds" interpretation of quantum mechanics, where the universe "forks" at every quantum possibility into an infinite number of universes. That's one type of multiverse. A "Multiverse" is a superset of that idea—it simply means a condition of many universes existing. They could have arisen in the same way ours did through a "big bang" in…

That's just one of dimensions 7-10. http://www.universetoday.com/48619/10-dimensions/

Re: At Multiverse Impasse, a New Theory of Scale

#87

Post by marktangotango »

clusterfoo wrote: post #75
calinet6 wrote: post #41

Earlier quoted context omitted.

It "kills it" because it's only really appealing if the universe we're in appears extremely unlikely, like it's the "just right" goldilocks balance of cosmic variables that we can't explain, that happened to be the stable ones that resulted in life evolving eventually. If the universe is actually very likely to occur in the state that it's in, then we don't need to use this "vast multiverse where our universe was the…

Naive question (I know nothing about this stuff): If mathematical logic is a property of our universe, then aren't we again entering the realm of circular logic? i.e: "Given the logical frameworks that are correct in our universe, our universe is very likely." Unless math is something that somehow exists independently of our physical universe... but then "where" does it come from?

Neal Stephenson explores this line of questioning in a fun way in the novel Anathem.

Re: At Multiverse Impasse, a New Theory of Scale

#88

Post by angersock »

MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

So, erm, what does that buy us?

I'm just an engineer, so I'm not sure I see the utility in any of that--sorry to sound closed-minded, but am genuinely curious.

Re: At Multiverse Impasse, a New Theory of Scale

#89

Post by derefr »

jwuphysics wrote: post #84
MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

I study astrophysics, so I won't be able to say much about SUSY or string theories or conformal field theories. I do agree that we're living in a golden age of physics! But your second and third points, inflation and SUSY-- those are definitely not confirmed. In fact, the primordial gravitational waves from BICEP2 are almost certainly dust contamination signal (e.g., http://arxiv.org/abs/1405.5857 ). The discovery of…

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet.

Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If they disconfirmed it, that'd be surprising.

Re: At Multiverse Impasse, a New Theory of Scale

#90

Post by Strilanc »

trhway wrote: post #14

>With their field stuck at a nasty impasse of course. Natural thing when a field is dominated by orthodoxy that closes their eyes to everything that they don't want to see. Like yesterday "entangled photon imaging" where what really happens is that a beam modulated by an image heats/excites crystal (with that heating/excitement thus obviously modulated by the image) which generates another beam (thus that another bea…

I'm not sure why you're grouping entanglement in with the multiverse.

One of those is a theoretical idea for reducing the Solomonoff complexity of the universe with no clear experimental implications. The other is an integral component of how we predicted and explain experimentally confirmed phenomena like violations of Bell's inequalities, the Elitzur-Vaidman bomb tester, quantum cryptography, and quantum teleportation.

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