Klein-Gordon quantum relativistic equation negative energy
60289
How does QFT interpret the Negative probability problem of the real scalar fields' Klein-Gordon equation?
149674
Kinetic energy of a photon and Schwarzschild radius
152198
Is it possible for $\Delta x$ ($\sigma_x$) of any free particle wave packet to be decreasing at any time?
88658
Confusion regarding the principle of least action in Landau & Lifshitz "The Classical Theory of Fields"
41407
How to derive or justify the expressions of momentum operator and energy operator?
150985
Why can't the Klein-Gordon equation explain the hydrogen atom but the Dirac equation does?
141320
Particle energy in general relativity?
14373
In physics sometimes we find energy that is negative. What does the negative sign indicate?
111578
Why is gravitational potential energy negative, and what does that mean?
63304
The Dirac-delta function as an initial state for the quantum free particle
53170
Energy conservation in General Relativity
118346
Normalizing the solution to free particle Schrödinger equation
22829
Black holes and positive/negative-energy particles
41209
Does matter with negative mass exist?
45501
Why does the negative sign arise in this thermodynamic relation?
131016
Question about Klein-Gordon field Lagrangian
26125
Does the canonical commutation relation fix the form of the momentum operator?