It’s a quality. Potential for change. Without potential for change, it’s inertial.
If the whole universe was inertial, there’d be no interaction between anything and the Universe would have 0 energy.
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Example: Neutrinos.
They’re considered “low-energy” because they don’t do any “work” – that is, they don’t affect change in much of anything.
They’re considered “low-energy” because they don’t do any “work” – that is, they don’t affect change in much of anything.
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What I love about Feynnman is that he didn’t give the “final word” on things but left things open for us to ponder as it’s through that pondering that leads to understanding and discoveries.
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In these lectures, you can see the germs of ideas in his mind that led to https://en.wikipedia.org/…/Wheeler%E2%80%93Feynman… quantum electrodynamics and quantum field theory
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