Recent content by Someone_physics

I'll have a look. In a similar spirit to page 21 I can modify the last inequality by stating the time taken for the sudden approximation to be valid is \tau = t_{1/2} - t_0 >> \frac{\hbar}{\langle \Delta E \rangle} The time after the sudden approximation is measured is given by \Delta t_1 =...

Can I have a reference for this? I've skimmed through a book of RQM (https://www.springer.com/gp/book/9783540674573) which makes not mention of this :/

Background --- Consider the following thought experiment in the setting of relativistic quantum mechanics (not QFT). I have a particle in superposition of the position basis: H | \psi \rangle = E | \psi \rangle Now I suddenly turn on an interaction potential H_{int} localized at r_o =...

Question --- So I've done a calculation which seems to suggest if I combine the system of a measuring apparatus to say an experimenter who "reacts" to the outcome of the the measurement versus one who does not. Then the change in entropy in both these situations is bounded by: $$ \Delta S_R...

I don't see why ##|x>## or ##|p>## can't be expressed as a superposition of energy-eigenstates and be plugged into the Schrödinger equation. Honestly, I was thinking of doing this in quantum mechanics. The main motivation of this calculation is, It is known (see...

Question --- I can show for a position eigenstate ## | x \rangle ## if it evolves in time ##U(\Delta t) | x\rangle ## (where ##U## is the unitary operator). Then one can bound the time elapsed by finding the probability amplitude ##| \langle x | U^\dagger(\Delta t)| x + \Delta x \rangle |^2 ##...