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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

#41

Post by calinet6 »

mSparks wrote: post #11

I don't see why this kills the multi verse theory. Which is a basic conclusion of a 10 dimensional space-time environment that doesn't include mass anyway.

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 one that produced an observer" explanation. It could be a single universe in all of existence, where everything makes sense mathematically and no further posturing is required in that silly unscientific field of cosmic philosophy.

Or if it fails, and it remains that our universe is unexpectedly perfect, then we are forced to resort to statistical explanations within an impossible-to-observe external multiverse. Scientists don't very much like conclusions built on not being able to observe things.

Though to me, the multiverse theory has a sort of fractal appeal to it. It is surely applicable to our planet, after all. Why not our entire universe?

Re: At Multiverse Impasse, a New Theory of Scale

#43

Post by noiv »

givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

I think, we are not bad at describing reality, the problem is describing our self, because whatever the outcome is it doesn't sound, well, motivating?

Re: At Multiverse Impasse, a New Theory of Scale

#44

Post by danbruc »

givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

For the moment it seems to me that there is no chance to ever know what something REALLY is. There is obviously stuff out there that behaves exactly like mathematical models we made up - there are things called electrons behaving like our model of electrons interacting with things called photons behaving like our models of photons. But what does this tell you about the nature of electrons and photons? Is a electron just a handful of numbers like charge -1 and spin 1/2 behaving according to the laws of physics or is there more to an electron? I can't even imagine how one could bridge the gap between our models of reality and reality but then there is probably so much more to learn about our universe, maybe some day...

Re: At Multiverse Impasse, a New Theory of Scale

#45

Post by axilmar »

givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

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.

Re: At Multiverse Impasse, a New Theory of Scale

#47

Post by tinco »

calinet6 wrote: post #41
mSparks wrote: post #11

I don't see why this kills the multi verse theory. Which is a basic conclusion of a 10 dimensional space-time environment that doesn't include mass anyway.

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…

A cool thing about the multiverse is that it makes a team out of us and the rest of our universe. 'We' are the universe that became stable and self aware, in contrast to many other universes. 'We' are a self aware universe. You, me, and the rest of the universe together, so we should act like it.

Re: At Multiverse Impasse, a New Theory of Scale

#48

Post by k__ »

snarfy wrote: post #40
givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

"Any effectively generated theory capable of expressing elementary arithmetic cannot be both consistent and complete. In particular, for any consistent, effectively generated formal theory that proves certain basic arithmetic truths, there is an arithmetical statement that is true, but not provable in the theory" - Gödel (Kleene)

Some CS prof. told us this in first semester. After that, Physics was over for me.

And I felt that the Planck-scale was somehow a proof for this.

Re: At Multiverse Impasse, a New Theory of Scale

#50

Post by JackC »

For a heroic attempt to explain this article to laypeople, check out physicsmatt's comments over at Metafilter:

"First, for maximum sense-making, read my previous comments here, here, here, and here. I realize that's a lot, sorry. The Universe is complicated. Then, for what follows, recall that to a particle physicist such as myself, there is no difference between lengths and energies (or indeed, any other dimensional quantity). Length is inverse energy: very energetic phenomenon probe very small lengths ...."

https://www.metafilter.com/142211/Multiverse-No-More-a-New-T...

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