Is quantization of energy a purely mathematical result or is there a fundamental reason behind it?
591
Reason for the discreteness arising in quantum mechanics?
112899
Final theory in Physics: a mathematical existence proof?
88926
Why do we use operators in quantum mechanics?
29728
Does the vacuum in QFT have nonzero energy or not?
100748
Probability, quantum physics, and why (can't it/does it) apply to macroscale events?
22958
Is there such a thing as charge density in quantum mechanics?
148541
Quantization of a particle on a spherical surface
2657
Can energy be taken out of the QFT vacuum?
81503
Do photons truly exist in a physical sense or are they just a useful concept like $i = \sqrt{-1}$?
48440
Quantum made easy: so what *is* quantum mechanics all about?
46450
Physical meaning of quantum operators
146039
Is it always possible to define energy of a system?
90716
Conservation of energy and wavefunctions
39017
The notion of an adiabatic process in thermodynamics -vs- quantum mechanics
100870
In De Broglie's Explanation for Bohr's Quantization Condition, why do we not use 2πr = n λ/2, why do we use 2πr = n λ?
10504
What are the reasons to expect that gravity should be quantized?
143668
Theoretical reasons for charge quantization