Perturbing about the Renormalized Field Theory: What justifies perturbing if the counter-terms are large?
67261
How does a perturbation theory make sense in quantum field theory?
45061
Physical interpretation of $Q^i = \partial _\nu T^{i \nu}$
18414
Energy-Momentum Tensor in QFT vs. GR
983
Use partial or covariant derivatives when deriving equations of a field theory?
49348
S. Weinberg, “The Quantum theory of fields: Foundations” (1995), Eq. (9.2.15)
86967
The concept of particle in QFT
94433
Rigorous underpinnings of infinitesimals in physics
35694
Can virtual particles be thought of as off-shell Fourier components of a field?
131016
Question about Klein-Gordon field Lagrangian
44239
Why the extra term $\frac{1}{2}(\partial_{\rho}A^{\rho})^2$ in the photon Lagrangian?
150395
Struggling to understand degenerate perturbation theory
136886
Large sample asymptotic/theory - Why to care about?
29329
Does a four-divergence extra term in a Lagrangian density matter to the field equations?
48192
Staggered Indices ($\Lambda^\mu{}_\nu$ vs. $\Lambda_\mu{}^\nu$) on Lorentz Transformations
7555
Why do we consider Lagrangian densities in field theory (as opposed to Lagrangians as in point mechanics)?
121584
Rigor in quantum field theory
130259
Is the S-Matrix the only quantum field observable?