What would it mean if symmetries in physics would not be fundamental?

In summary, physicist Joseph Polchinski argues that string theory allows for no exact global symmetries and the concept of local (gauge) symmetries has been challenged as well. He suggests that no symmetries, global or local, should be considered fundamental in nature and that they may all be emergent rather than inherent. This raises questions about the fundamental nature of all laws of physics. Additionally, Polchinski's work primarily focuses on string theory and its related models, which may propose the idea that all symmetries in nature are not fundamental. Ultimately, the concept of emergence and the process of establishing fundamental laws remains a complex and ongoing discussion in the scientific community.
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Suekdccia
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What would it mean if all symmetries in physics would not be fundamental?
Physicist Joseph Polchinski wrote an article (https://arxiv.org/pdf/1412.5704.pdf) where he considered the possibility that all symmetries in nature may not be fundamental. He says at page 36:

"From more theoretical points of view, string theory appears to allow no exact global symmetries, and in any theory of quantum gravity virtual black holes might be expected to violate all global symmetries

Moreover, as we have already discussed in §2, local (gauge) symmetries have been demoted as well, with the discovery of many and varied systems in which they emerge essentially from nowhere. It seems that local symmetry is common, not because it is a basic principle, but because when it does emerge it is rather robust: small perturbations generally do not destroy it. Indeed, it has long been realized that local symmetry it is ‘not really a symmetry,’ in that it acts trivially on all physical states. The latest nail in this coffin is gauge/gravity duality, in which general coordinate invariance emerges as well.

This leaves us in the rather disturbing position that no symmetry, global or local, should
be fundamental (and we might include here even Poincaré invariance and supersymmetry).
Susskind has made a distinction between the mathematics needed to write down the equations describing nature, and the mathematics needed to solve those equations. Perhaps symmetry belongs only to the later."


I have a few questions about this:

1. If all symmetries (even the most fundamental ones) would not fundamental after all, would it mean that no laws of physics are really fundamental? If all symmetries and all laws associated with them would not be fundamental, would that mean that literally all laws of physics would not be fundamental but rather emergent?

2. Polchinski has mostly worked on string theory and models related with it. Is it there any type of string theory or any kind of model/theory related with it which proposes that all symmetries may not be fundamental?
 
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Suekdccia said:
If all symmetries (even the most fundamental ones) would not fundamental after all, would it mean that no laws of physics are really fundamental?
No, it would mean that no currently known laws of physics are really fundamental.
 
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Suekdccia said:
1. If all symmetries (even the most fundamental ones) would not fundamental after all, would it mean that no laws of physics are really fundamental? If all symmetries and all laws associated with them would not be fundamental, would that mean that literally all laws of physics would not be fundamental but rather emergent?
While I agree with what Demystifier says in principle., i would raise the question also to elaborate on what emergence means, and what it actually means to establish that laws are fundamental? One possibility here is the position that the process of emergent laws is a physical one, and that no finite time process can ever claim to reach an confident eternal truth.

Suekdccia said:
It seems that local symmetry is common, not because it is a basic principle, but because when it does emerge it is rather robust: small perturbations generally do not destroy it...
this line of thinking is in line with the idea that process of communication rules, or laws, as an eternal ongoing process and all we can state or observer is current local steady states with effective fapp symmetries. The fallacy is when theorists mistake them for eternal fundamental and exporapolate them widely in both time directions. Examples of this is: Extrapolated laws established from Earth based science into some very speculative ideas of quantum cosmology. At minimum even unlike thinkers should be able to agree that it is speculative.

/Fredrik
 
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