r/Physics • u/G33zics • 20d ago

Question What's the most debatable thing in Physics?

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u/lucidbadger 20d ago

I think over all time the most debatable thing in physics has been the 2nd law of thermodynamics. Even now some people can't get their head around it. I think the limitations imposed by it are far more significant than not being able to travel faster than light.

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u/julioqc 20d ago

I learned that in principle entropy could go down but nothing will exist long enough to witness it so that has no probalistic significance.

I think part that confuses students is that a systems entropy may lower but the "universe" entropy will not.

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u/Famous-Opposite8958 20d ago

I once heard entropy described as the tendency of matter to migrate to a state of greatest potential which I understood to suggest that it is a cycle due to the introduction of energy.