Questions tagged [locality]
The locality tag has no usage guidance.
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What combinations of realism, non-locality, and contextuality are ruled out in quantum theory?
Bell's inequality theorem, along with experimental evidence, shows that we cannot have both realism and locality. While I don't fully understand it, Leggett's inequality takes this a step further and ...
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If $: V(\phi) :$ is non-local in space, does that mean interacting quantum field theory is non-local?
Free field theories are definitely local in.
In the interaction picture, we can decompose the fields into creation operator modes and annihilation operator modes. The product of operators can be ...
user2124
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How fast does gravity propagate?
A thought experiment: Imagine the Sun is suddenly removed. We wouldn't notice a difference for 8 minutes, because that's how long light takes to get from the Sun's surface to Earth.
However, what ...
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Why is lagrangian density with interactions correct?
The textbooks I have available explain that due to the infinite degrees of freedom of a field, the relevant object in QFT is the Lagrangian density. A Lagrangian is then obtained for the field by ...
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Why is quantum entanglement considered to be an active link between particles?
From everything I've read about quantum mechanics and quantum entanglement phenomena, it's not obvious to me why quantum entanglement is considered to be an active link. That is, it's stated every ...
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