Can the charge of $d$, $s$ and $b$ quarks be thought of as unitary charge?
33784
Is it a coincidence that quarks have exactly -1/3 or 2/3 the electron's charge?
29688
Why are scattering matrices unitary?
21581
Empirical bound on sum of electron and proton charge
152110
How does $p\cdot u$ relate to observed energy and momentum for a massive particle?
135502
How many physical degrees of freedom does the $\mathrm{SU(N)}$ Yang-Mills theory have?
143668
Theoretical reasons for charge quantization
50178
\qed for theorems without proofs
4789
Apparent Violation of Newton's $3^{\text{rd}}$ Law and the Conservation of Momentum (and Angular Momentum) For a Pair of Charged Particles
87921
Why is the up quark is lighter than the down quark, while top is heavier than bottom?
69799
Why, fundamentally, are particles charged?
29152
Conversion of the Polyakov action into the Nambo-Goto action?
51601
Double counting potentials in $N$-Body Problem?
10413
Why do quarks tend to bond in groups of three?
83220
If $U$ is unitary operator then spectrum $\sigma(U)$ is contained inside the unit circle
86967
The concept of particle in QFT
22040
Why is there no theta-angle (topological term) for the weak interactions?
13683
How is $J^{PC}$ value experimentally determined for new types of particles?