Why should an action in SR be a lorentz scalar?
87125
Does action really have to be Lorentz-invariant in SR?
136921
Is the Lorentz force expression valid for magnetic field created by a magnetic monopole?
143315
How does the Lorentz group act on a 4-vector in the spinor-helicity formalism $p_{\alpha\dot{\alpha}}$?
105660
Invariance of action $\Rightarrow$ covariance of field equations?
122357
Discreteness of Spacetime and Violation of Lorentz symmetry
88658
Confusion regarding the principle of least action in Landau & Lifshitz "The Classical Theory of Fields"
131965
Why can't a real scalar couple to the electromagnetic field?
43304
Lorentz transformation of Gamma matrices $\gamma^{\mu}$
13786
A question in Special Relativity
82624
"Newtonian limit" property of special relativity
18583
What conservation law corresponds to Lorentz boosts?
61070
Lorentz invariance of the integration measure
38723
Can Poincare representations be embedded in non-standard Lorentz representations?
140184
Why all theories are Lorentz invariant?
131016
Question about Klein-Gordon field Lagrangian
74702
Are Lorentz transformations linear transformations?
83175
Infinitesimal transformations for a relativistic particle