Phototubes

Photo-tubes cut off (don't respond to photons) at sufficiently small wavelengths. This is because the photo-tube's glass does not transmit UV. They also cut off at sufficiently large wavelengths, where the glass does transmit the light. Why?

Interference of light waves: Young's double slit experiment.

Imagine doing Young's two slit interference experiment with an average of one photon per second incident on the slits. If you cover one slit with your thumb every other second, will there be interference ? Why ? What's going on ? What pattern will you see if you average for a long time ?

'Quantum Mechanics'

This question is from the text book 'Quantum Mechanics' second edition by David J. Griffiths. (See attached file for full problem description) --- Problem 3.5 - The hermitan conjugate (or adjoint) of an operator Qprime... Problem 3.7 - The Hamiltonian and the initial state for a certain three-level system is given. Find its state at a time t

'Quantum Mechanics'

This question is from the text book 'Quantum Mechanics' second edition by David J. Griffiths. (See attached file for full problem description) --- Problem 3.27 - Sequential measurements. An operator Aprime, representing observable A, has two... ---

'Quantum Mechanics'

This question is from the text book 'Quantum Mechanics' second edition by David J. Griffiths. (See attached file for full problem description) --- Problem 3.39 - (a) For a function f(x) that can be described... - As a measure of how fast a system is changing... ---