Lie groups are crucial to some of the most fundamental theories in physics

Re:Lie groups are crucial to some of the most fundamental th... by elchananHaas on Wednesday December 03, 2025 @05:35PM (#46141215)

The consequence of Noether's theorem is that if a system is time symmetric then energy is conserved. On a global perspective, the universe isn't time symmetric. It has a beginning and an expansion through time. This isn't reversible so energy isn't conserved.

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Re:Lie groups are crucial to some of the most fundamental th... by measurablefunc on Wednesday December 03, 2025 @06:22PM (#46141682)

I think you're confused about what the theorem says & how it applies to formal models of reality.

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Re:Lie groups are crucial to some of the most fundamental th... by lupire on Thursday December 04, 2025 @12:41PM (#46150431)

Please explain. Noether's theorem equates global symmetry laws with local conservation laws. The universe does not in fact have global symmetry across time.

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Re:Lie groups are crucial to some of the most fundamental th... by measurablefunc on Thursday December 04, 2025 @02:15PM (#46151574)

You are making the same mistake as OP. Formal models and their associated ontology are not equivalent to reality. If you don't think conservation principles are valid then write a paper & win a prize instead of telling me you know for a fact that there are no global symmetries.

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Re:Lie groups are crucial to some of the most fundamental th... by lupire on Thursday December 04, 2025 @03:23PM (#46152500)

The Nobel Prize is yours to collect: https://en.wikipedia.org/wiki/Expansion_of_the_universe

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Re:Lie groups are crucial to some of the most fundamental th... by measurablefunc on Thursday December 04, 2025 @03:47PM (#46152823)

I have other interests but you are welcome to believe in whatever confabulation of formalities that suit your needs.

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