Has a surfer Ph.D. rewritten physics? Maybe. • Hacker News Board

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#11

Post by brentr » Sun, Jul 27, 2008, 6:13 PM UTC

I don't remember where I read it, nor the exact wording, but there is a quote that is perfect for this. It went something like this, "Godel proved incompleteness. Anyone who thinks there is a theory of everything laughs in the face of Godel."

My point is that physics does not exist in a vacuum. It is built up from observational data found in nature and taken from experiments. If mathematics can't come to complete truth (Godel has proven this), then there is no hope for a theory of everything in something that uses mathematics as its language.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#12

Post by robg » Sun, Jul 27, 2008, 6:14 PM UTC

gaika wrote: post #8

whordeley wrote: post #7

Earlier quoted context omitted.

Oh. That made perfect sense. Can you summarize?

From the link: "the overlap between the set of people who know some group theory and those who are (still) interested in giving Lisi’s “Theory of Everything” a passing thought is empty."

From the article, Lee Smolin (http://www.leesmolin.com/) has already put out a paper building on Lisi's approach.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#13

Post by DanielBMarkham » Sun, Jul 27, 2008, 6:20 PM UTC

brentr wrote: post #11

I don't remember where I read it, nor the exact wording, but there is a quote that is perfect for this. It went something like this, "Godel proved incompleteness. Anyone who thinks there is a theory of everything laughs in the face of Godel." My point is that physics does not exist in a vacuum. It is built up from observational data found in nature and taken from experiments. If mathematics can't come to complete tru…

I'm with you about 80% of the way here.

Godel showed (and guys tell me if I mess this up) that formal self-consistent systems have both statements that are true that cannot be proven and false statements that cannot disproved. In other words, complete systems are incomplete.

This does not mean that complete systems cannot model reality to a high degree -- there's no reason why a ToE could pop out from some rotation or transmutation of mathematics. It just means there would be parts of it that would be incomplete -- the model itself could have a very high degree of fidelity.

When applied to higher math and physics, this is another way of saying "you don't know what you don't know" ie, the models can work perfectly across all observation space and still be true to Godel.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#14

Post by sarehu » Sun, Jul 27, 2008, 6:21 PM UTC

brentr wrote: post #11

I don't remember where I read it, nor the exact wording, but there is a quote that is perfect for this. It went something like this, "Godel proved incompleteness. Anyone who thinks there is a theory of everything laughs in the face of Godel." My point is that physics does not exist in a vacuum. It is built up from observational data found in nature and taken from experiments. If mathematics can't come to complete tru…

That's complete nonsense. There's nothing about Godel's theorem that says the physical rules of the universe can't be described. You're babbling religiously.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#15

Post by senthil_rajasek » Sun, Jul 27, 2008, 6:25 PM UTC

Here is a nice observation from Lee Smolin about this theory,

"I don't see it as a finished theory," he says of Lisi's formulation. "I see it as some mathematical observations and then a proposal."

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#16

Post by brentr » Sun, Jul 27, 2008, 6:26 PM UTC

sarehu wrote: post #14

brentr wrote: post #11

I don't remember where I read it, nor the exact wording, but there is a quote that is perfect for this. It went something like this, "Godel proved incompleteness. Anyone who thinks there is a theory of everything laughs in the face of Godel." My point is that physics does not exist in a vacuum. It is built up from observational data found in nature and taken from experiments. If mathematics can't come to complete tru…

That's complete nonsense. There's nothing about Godel's theorem that says the physical rules of the universe can't be described. You're babbling religiously.

Check out the following entry on Wikipedia related to Godel's Incompleteness Theorem and the Theory of Everything

http://en.wikipedia.org/wiki/Theory_of_everything

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#17

Post by robg » Sun, Jul 27, 2008, 6:40 PM UTC

canoebuilder wrote: post #4

I'm not entirely keen on the hubbub refered to(the articles on Lisi from about this time last year?) Here is another article I read the other day, probably pretty similar, but it wasn't bad http://www.newyorker.com/reporting/2008/07/21/080721fa_fact_...

Not surprising given the source, but that's a much better version. Thanks.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#18

Post by sarehu » Sun, Jul 27, 2008, 6:45 PM UTC

brentr wrote: post #16

sarehu wrote: post #14

Earlier quoted context omitted.

That's complete nonsense. There's nothing about Godel's theorem that says the physical rules of the universe can't be described. You're babbling religiously.

Check out the following entry on Wikipedia related to Godel's Incompleteness Theorem and the Theory of Everything http://en.wikipedia.org/wiki/Theory_of_everything

What about it? All Godel's incompleteness theorem says is that there will be open questions about a universe describable by finitely many rules. The laws of physics don't need to provide answers to questions about whether computers in its universe will halt or whether planetary systems are stable.

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#19

Post by Allocator2008 » Sun, Jul 27, 2008, 6:47 PM UTC

Well leaving aside Godel, I think one can have a theory of everything that has, as Rumsfeld would say, "known unknowns", i.e., a theory of everything which "manages" in some way unknown parameters. Like infinities in quantum field theory go away by the nature of string theory's elimination of arbitrarily small distances. Anyway. I think I'm keeping my money on string theory, but an interesting thought nonetheless!

Re: Has a surfer Ph.D. rewritten physics? Maybe.

#20

Post by brentr » Sun, Jul 27, 2008, 6:51 PM UTC

sarehu wrote: post #18

brentr wrote: post #16

Earlier quoted context omitted.

Check out the following entry on Wikipedia related to Godel's Incompleteness Theorem and the Theory of Everything http://en.wikipedia.org/wiki/Theory_of_everything

What about it? All Godel's incompleteness theorem says is that there will be open questions about a universe describable by finitely many rules. The laws of physics don't need to provide answers to questions about whether computers in its universe will halt or whether planetary systems are stable.

What do you mean "the laws of physics don't need to provide answers to whether planetary systems are stable"? Since when are planetary systems outside of physics?

Your sentence "All Godel's incompleteness theorems says is that there will be open questions about a universe describable by finitely many rules" shows right there that there cannot be a theory of everything. How can you have a theory of everything yet still have open questions? That means that you have not answered everything.