Internal symmetry not of spacetime

[AntonioLao]

Steven Weinberg shared the 1979 Nobel Prize in Physics with Salam and Glashow for the discovery of the electroweak force. In his Nobel Lecture dated December 8, 1979,

http://nobelprize.org/physics/laureates/1979/weinberg-lecture.pdf, he talks about two research approaches in theoretical physics. (1) The approach of investigating the powerful abstract concept of symmetry. (2) The approach of controlling the monsters of infinity in quantum field theories. The solutions of these two investigations are the discoveries of various principles of symmetry and principles of renormalization.

However, some internal symmetry principles lie outside the invariance group of spacetime: isospin symmetry, strangeness, parity, and ‘eightfold’ symmetry, this last is an approximate symmetry. Nevertheless, all of these are categorized under the ‘global’ symmetry group, whose transformations do not depend on position in space and time.

[Guille]

I think that the renormalization that is done to solve the infinity problems is an error. Renormalization, up to what I know, is a fakening of what there really is, an adaptation. Infinity shouldn't be avoided, there is not need for this, we should just beable to understand infinity and control it, have an absolute logical control of infinity in mathematics, for me, is the main task for mathematicians and matheamtical physicists nowadays.

About symetry, I had an idea which I think could be interesting: The amount of symetry in the universe is inverselly proportional to the amount of entropy. And thus, the disorder in the universe grows, and the disorder is what makes things un-symetric, so the symetry lowers when the disorder grows.

What do you think about my idea?

[AntonioLao]

increasing entropy is increasing randomness and increasing randomness is increasing symmetry. Chaos is perfect symmetry or directional invariance. Order is directional.

[Guille]

increasing entropy is increasing randomness and increasing randomness is increasing symmetry. Chaos is perfect symmetry or directional invariance. Order is directional.

WHAT?

I mean, I think completely opposite.

INCREASING THE DISORDER AND RANDOMNESS DECRESES THE SYMETRY.

How can something have symetry if it's completely caotic?

[dleviwing]

Quite right Guille;
Chaos started the universe and it will end with symmetry.
Entropy leads to symmetry not chaos.
Antonio however is making reference to other symmetry concepts other than the commonly accepted notions.

[AntonioLao]

GUILLE,

Total randomness implies no probability distribution, normal or otherwise. All events are equally likely. This is like the quantum fluctuation of the vacuum. The optimal temperature can be zero or infinite depending on the starting perspective. At infinite temperature, the system is totally chaotic and nonlinear hence unpredictable and infinite degrees of freedom. At the other extreme of zero temperature, the system is in complete orderliness and there is no motion, the temperature is exactly zero.

[Guille]

GUILLE,

Total randomness implies no probability distribution, normal or otherwise. All events are equally likely. This is like the quantum fluctuation of the vacuum. The optimal temperature can be zero or infinite depending on the starting perspective. At infinite temperature, the system is totally chaotic and nonlinear hence unpredictable and infinite degrees of freedom. At the other extreme of zero temperature, the system is in complete orderliness and there is no motion, the temperature is exactly zero.

Thanks now, I understand what this symetry means.

Thanks also dave.

[subversion]

can somebody please explain the infinity problem to me and why it was solved with renormalization. I'm not well versed in QM. thanks

[Guille]

can somebody please explain the infinity problem to me and why it was solved with renormalization. I'm not well versed in QM. thanks

I don't have detailed information, but I know that the infinite problem is that when equations from especial and general relativity are mixed with the equations of quantum mechanics, then absurd answers such as infinite appear as results, and this is a problem. It hasn't been absolutelly solved (I think), because if it would have been solved, then we would have a TOE (basically, toe is unification of qm and gr).

[AntonioLao]

can somebody please explain the infinity problem to me and why it was solved with renormalization. I'm not well versed in QM. thanks

another explanation of the infinity monster is that there is no such thing as a probability greater than unity. For example, adding all the probabilities of all paths in a Feynman path integral or the perturbative addition of all loops in a Feynman diagram. The sum of all probability must always be less than or equal to unity.

[math]\\int^{\\infty}_{-\\infty} p(t) dt \\leq 1 [/math]

In layman terms, absolute certainty can never exceed 100%. I'm 100% sure.