- #1
asimov42
- 377
- 4
Hi all,
Just a clarification to ask about: if a have an electron (all by its lonesome) in its ground state, it will have non-zero kinetic energy (zero-point energy), even at absolute zero. This should mean the particle (oscillating field excitation in QFT) is always moving.
Now, to be clear, I may measure the momentum of the particle to be zero several times in a row, statistically speaking (to the best accuracy of my measurement device). The energy is the expectation of the Hamiltonian - so despite those measured values, the particle has a fixed zero-point kinetic energy and is always in motion.
Sorry, this is probably obvious - I'm basically asking about relationship between energy as the expectation, and the fact that you may randomly measure the particle momentum to be zero at certain times despite the fact it has non-zero energy always.
Just a clarification to ask about: if a have an electron (all by its lonesome) in its ground state, it will have non-zero kinetic energy (zero-point energy), even at absolute zero. This should mean the particle (oscillating field excitation in QFT) is always moving.
Now, to be clear, I may measure the momentum of the particle to be zero several times in a row, statistically speaking (to the best accuracy of my measurement device). The energy is the expectation of the Hamiltonian - so despite those measured values, the particle has a fixed zero-point kinetic energy and is always in motion.
Sorry, this is probably obvious - I'm basically asking about relationship between energy as the expectation, and the fact that you may randomly measure the particle momentum to be zero at certain times despite the fact it has non-zero energy always.