Is Everything in the Universe Truly a Mathematical Structure?

[MathematicalPhysicist]

One of the main assumption is computability, i.e., that every result can be obtained by applying an algorithm and performing a FINITE number of steps with it. By this criterion, even the circumference of a unit circle cannot be computed, because pi=3.14159265...
cannot be calculated by a finite number of steps. In my opinion, this implies that Nature is not such an algorithm (a Turing machine), so the Godel theorem is not applicable to the behavior of Nature. (Another possibility is that Nature does not really work with pi, but with a rational number that only approximates pi. Such a Universe could be computable, but not elegant.)

should i recall you calculus where pi is an irrational number which is the limit of a sequence of rational numbers, i think you and others mistakingly mix between the use of maths in physics and maths by its own merits.

 

[Demystifier]

should i recall you calculus where pi is an irrational number which is the limit of a sequence of rational numbers, i think you and others mistakingly mix between the use of maths in physics and maths by its own merits.

I do not see how it is related to what I said.

 

[Demystifier]

http://arxiv.org/abs/0704.0646

I predict that this paper will become famous and frequently cited, not only by those who will like it, but also by those who will not.
Does anyone wants to take a bet?

By the way, I am not one of those who will particularly like it.

Now more then 2 years later let us see if I was right.

At the moment it has 15 SPIRES citations. It is not very impressive, so I was not right that it will become frequently cited.

Still, I think I was right that it will become famous. For example, it has 19 blog links, which is quite impressive.

 

[Demystifier]

Now I've noticed that this thread is moved on Math and Science Software forum from Beyond the Standard Model forum. This thread certainly does not belong to Math and Science forum. Could someone in charge move it on a more appropriate place?

 

[pellman]

I just had a brief look at the paper for the first time today.

The most weird thing with the mathematical universe is that, according to Tegmark, EVERY mathematical structure exists, and no mathematical structure is more real then other. Thus, not only quantum mechanics is real, but also classical mechanics is real, Ptolomei mechanics is real, a model in which the universe is a dodecahedron is real, anything. It seems that almost every paper on physics is correct, provided that a purely mathematical mistake has not been made. In fact, such papers with mathematical mistakes are also correct, because these papers themselves are also mathematical structures (because everything is a mathematical structure).

this is essentially the same as my thoughts on it. If we ask, "why is our universe the way it is, and not some other way?" or "why is there a universe and not merely nothing?" the answer has to be contingent, "baggage" in Tegmark's view, and not in the math itself. The alternative is that all possible universes exist (and maybe some impossible ones). everything happens. There is no answer.Another problem is multiplicity itself. On page 4 Tegmark notes that "if two structures are isomorphic, then there is no meaningful sense in which they are not one and the same". so how do we have a universe containing such a vast number of phenomena described by the same mathematics if there is nothing underneath but the mathematics itself? How are they distinguished? I admit, though, it is likely that I pose this question because I don't really understand Tegmark well enough.

So, if Tegmark is right, what is the point in doing science?

It's fun.