<we><edit> <!-- questions and answers -->
tensor-calculus
angular-momentum
fluid-dynamics
charge
radiation
renormalization
photons
experimental-physics
electromagnetism
quantum-electrodynamics
temperature
operators
homework-and-exercises
astrophysics
visible-light
work
time
electric-circuits
wavefunction
momentum
soft-question
forces
potential
potential-energy
acceleration
quantum-field-theory
The interrelation of the different forms of coupling constants
quantum-field-theory
renormalization
Auxiliary field path integral in nonlinear sigma models
quantum-field-theory
string-theory
path-integral
sigma-models
functional-determinants
Understanding renormalizability and bare mass
quantum-field-theory
renormalization
Do spin states have a shape? If so, what are they?
quantum-mechanics
quantum-field-theory
particle-physics
quantum-spin
Can quantum particle wave functions be located on multiple points in space at once?
quantum-mechanics
quantum-field-theory
particle-physics
wavefunction
Dirac once said that renormalization is just a stop gap procedure, and there had to occur a fundamental change in our ideas. What changed?
quantum-field-theory
renormalization
effective-field-theory
Trying to work out the CP-transformation property of the Higgs potential
quantum-field-theory
symmetry
standard-model
higgs
cp-violation
One-point function and vacuum expectation value in $\phi^4$-theory
quantum-field-theory
particle-physics
symmetry-breaking
correlation-functions
1pi-effective-action
Field renormalization of $\phi^4$ to second order
quantum-field-theory
renormalization
Physical understanding of the change in scattering cross-sections at finite temperatures
quantum-field-theory
particle-physics
cosmology
scattering
thermal-field-theory
Is the String Field of String Field Theory the same (ontologically identical to) as the field of QFT?
quantum-field-theory
string-theory
string-field-theory
Solving the Klein-Gordon Equation with a Fourier Transform
homework-and-exercises
quantum-field-theory
klein-gordon-equation
Funny term in my Lagrangian
quantum-field-theory
lagrangian-formalism
higgs
term-symbols
Temperature in the Hamiltonian limit
quantum-field-theory
statistical-mechanics
temperature
hamiltonian
ising-model
Gauge invariance is just a redundancy. Why is massive abelian gauge field renormalizable but massive non-abelian gauge field nonrenormalizable?
quantum-field-theory
gauge-theory
renormalization
Getting particles from fields: normalization issue or localization issue?
quantum-field-theory
hilbert-space
normalization
Spin magnetic moment direction of a particle
quantum-mechanics
quantum-field-theory
quantum-spin
Positive and negative energy modes of scalar field
quantum-field-theory
fourier-transform
klein-gordon-equation
Is anti-matter matter going backwards in time?
quantum-field-theory
time
antimatter
How does QFT help with entanglement?
quantum-mechanics
quantum-field-theory
special-relativity
quantum-entanglement
Quantum electrodynamics extended with a special topological term
quantum-field-theory
topological-field-theory
Random phase approximation for interacting electron gas
quantum-field-theory
statistical-mechanics
condensed-matter
electrons
feynman-diagrams
Wick rotations, convergence and Feynman propagators?
quantum-field-theory
path-integral
regularization
wick-rotation
analyticity
Obstruction in calculating $\mathcal{Z}_{\mathcal{N}=1}$ SYM partition function
quantum-field-theory
gauge-theory
supersymmetry
renormalization
partition-function
Is the reduction of tensor loop integrals to scalar integrals using Passarino Veltman Functions, theory dependent?
quantum-field-theory
Ordering of factors when calculating Feynman Diagrams
quantum-field-theory
feynman-diagrams
"Dimensional analysis" arguments in quantum field theory
quantum-field-theory
renormalization
dimensional-analysis
regularization
Intuition behind mass corrections to massless fermions
quantum-field-theory
renormalization
Connection between Hubbard-Stratonovich and (generalized) coherent states
quantum-mechanics
quantum-field-theory
condensed-matter
many-body
coherent-states
Counting Degrees of Freedom in Field Theories
quantum-field-theory
field-theory
gauge-theory
classical-field-theory
degrees-of-freedom
Dilaton coupling to CFT
quantum-field-theory
conformal-field-theory
scale-invariance
Cutoff-dependent "inverse propagator" for renormalization
quantum-field-theory
renormalization
feynman-diagrams
propagator
Is the Feynman propagator integrable over Minkowski spacetime?
quantum-field-theory
mathematical-physics
feynman-diagrams
integration
propagator
Amplitude for Spacelike Separation of Particle in QM
quantum-mechanics
quantum-field-theory
integration
complex-numbers
Matter effects in neutrino oscillation
quantum-field-theory
particle-physics
neutrinos
Step involving delta-function in the Klein-Gordon equation solving
quantum-field-theory
dirac-delta-distributions
What's the key point to argue that pure gravity can't be renormalizable from two-loop?
quantum-field-theory
general-relativity
renormalization
quantum-gravity
qft-in-curved-spacetime
Invariance, covariance and symmetry
quantum-field-theory
symmetry
tensor-calculus
covariance
invariants
Why are derivatives in interaction terms treated differently from derivatives in the kinetic term?
quantum-field-theory
lagrangian-formalism
feynman-diagrams
perturbation-theory
interactions
Vertex factor for $\frac{g}{4} (A_{\nu}A^{\nu})^2$ in QED
homework-and-exercises
quantum-field-theory
lagrangian-formalism
feynman-diagrams
Perturbative reheating after Inflation in $\phi^4$ theory
quantum-field-theory
cosmology
cosmological-inflation
Massless $m=0$ 4D Fourier transform of $(p^2 + i \epsilon)^{-2}$
quantum-field-theory
fourier-transform
feynman-diagrams
dirac-delta-distributions
propagator
Klein-Gordon propagator integral in the light-like case
quantum-field-theory
path-integral
integration
Sakurai"s Comment Anti-particle in Klein-Gordon equation: Reversing momentum and Moving backward in time
quantum-mechanics
quantum-field-theory
special-relativity
time
antimatter
Connection between quantum field and the wavefunction
quantum-mechanics
quantum-field-theory
wavefunction
What are particles if quantum fields are not physical objects?
quantum-mechanics
quantum-field-theory
Schrodinger Wave Functional (quantum fields) - Solving Functional Gaussian Integrals
homework-and-exercises
quantum-field-theory
fourier-transform
propagator
Operator Product Expansion on cylinder
quantum-field-theory
conformal-field-theory
Fourier transform and momenta flow in Feynman diagram
quantum-field-theory
momentum
conventions
fourier-transform
feynman-diagrams
Are the field renormalization factors infinite or finite?
quantum-field-theory
renormalization
regularization
Transition amplitude of n-vacuua in QCD
quantum-field-theory
vacuum
quantum-chromodynamics
What's the geometric (or representation independent) definition of central charge of Lie algebra $\mathfrak{g}$?
quantum-field-theory
mathematical-physics
lie-algebra
lie-group
Bremsstrahlung and infrared divergences in Peskin & Schroeder 6.5
quantum-field-theory
quantum-electrodynamics
renormalization
scattering
photon-emission
Renormalization of a Feynman diagram with zero bare mass
quantum-field-theory
renormalization
integration
How is scale invariance broken in QCD?
quantum-field-theory
quantum-chromodynamics
scale-invariance
LSZ reduction theorem derivation in Weinberg QFT
quantum-field-theory
renormalization
non-perturbative
fock-space
Homework: Feynman diagram loops, confusion about natural units
homework-and-exercises
quantum-field-theory
feynman-diagrams
absolute-units
How to say "speed of light is constant in all frames" in QFT?
quantum-field-theory
special-relativity
reference-frames
inertial-frames
observers
QFT Hilbert spaces over other rings than the complex numbers $\mathbb{C}$
quantum-mechanics
quantum-field-theory
hilbert-space
complex-numbers
clifford-algebra
How do phase transitions really work in high energy / early universe physics?
quantum-field-theory
particle-physics
phase-transition
Intuitive sketch of the correspondence of a string theory to its limiting quantum field theory
quantum-field-theory
string-theory
Why pseudoscalar can decay to photons
quantum-field-theory
conservation-laws
standard-model
beyond-the-standard-model
parity
Spin Up with Indefinite Helicity
quantum-field-theory
dirac-equation
spinors
helicity
Contact terms in proof of Ward identity
quantum-field-theory
quantum-electrodynamics
ward-identity
On the generator $K$ of boost transformation in interacting system
quantum-field-theory
operators
hamiltonian
interactions
poincare-symmetry
Why is there a Cardy formula in 2d cft?
quantum-field-theory
gravity
conformal-field-theory
ads-cft
Why does the integral for a "generic one-loop snail diagram" in scalar QFT blow up?
quantum-field-theory
feynman-diagrams
integration
dimensional-analysis
singularities
How is the $\langle\psi| x(t')\, x(t)|\psi\rangle$ interpreted in the Heisenberg picture?
quantum-mechanics
quantum-field-theory
Why are short distances synonymous with high energies?
quantum-field-theory
Determining Feynman rules from Lagrangian
quantum-field-theory
lagrangian-formalism
quantum-electrodynamics
feynman-diagrams
Lorentz-invariant phase space for 2->2 scattering
quantum-field-theory
special-relativity
kinematics
integration
lorentz-symmetry
Could the unexpectedly fast accelerating expansion of the universe be caused by the theoretical graviton's anti-particle?
quantum-field-theory
particle-physics
gravity
What does "consistent at an infinitesimal level" mean?
quantum-field-theory
momentum
terminology
representation-theory
lie-algebra
Electrons in the nuclei
quantum-mechanics
quantum-field-theory
nuclear-physics
elementary-particles
Modern treatment of effective QFT in curved spacetime
quantum-field-theory
general-relativity
resource-recommendations
quantum-gravity
qft-in-curved-spacetime
The relation between anomalous dimensions and renormalization constants
quantum-field-theory
research-level
renormalization
dimensional-reg
Anomalous triangle vertex: divergencies and symmetry argument
quantum-field-theory
symmetry
gauge-invariance
regularization
quantum-anomalies
How to compute the normal ordered angular momentum of a Klein-Gordon real scalar in terms of ladder operators?
quantum-field-theory
angular-momentum
operators
homework-and-exercises
Coupling $A_\mu$ to Klein Gordon equation and action?
quantum-mechanics
electromagnetism
quantum-field-theory
lagrangian-formalism
gauge-invariance
Why can the Klein-Gordon field be Fourier expanded in terms of ladder operators?
quantum-field-theory
fourier-transform
klein-gordon-equation
Wilsonian definition of renormalizability
quantum-field-theory
renormalization
Boson on a Torus: mode expansion
quantum-mechanics
quantum-field-theory
conformal-field-theory
Hermiticity of Dirac Operator $\gamma^{\mu}D_{\mu}$ and Expansion in eigenmodes
quantum-field-theory
operators
dirac-equation
quantum-anomalies
Why don't we see macroscopic "electron waves"?
quantum-mechanics
quantum-field-theory
electrons
quantum-electrodynamics
Valid Bogoliubov transformation?
quantum-mechanics
homework-and-exercises
quantum-field-theory
Schwinger effect verified by Unruh temperature?
quantum-field-theory
virtual-particles
unruh-effect
Question about renormalization and parts of the Lagrangian
quantum-field-theory
renormalization
Canonical commutation relation field theory
homework-and-exercises
quantum-field-theory
fourier-transform
commutator
What is the physical meaning of nilpotent operator?
quantum-field-theory
gauge-theory
brst
Srednicki QFT Chapter 29: Feynman diagrams for calculating the effective action
quantum-field-theory
path-integral
feynman-diagrams
effective-field-theory
1pi-effective-action
Classical version of tree-level QFT correlation functions
quantum-field-theory
correlation-functions
classical-field-theory
Physical poles in QFT scattering amplitudes?
quantum-field-theory
scattering
Why does the axial/chiral gamma matrix $\gamma^5$ not exist in odd dimensions?
quantum-field-theory
dirac-equation
dirac-matrices
Antiparticle solution of the Dirac Equation
quantum-field-theory
antimatter
dirac-equation
charge-conjugation
What is an observer in QFT?
quantum-mechanics
quantum-field-theory
hilbert-space
quantum-interpretations
observers
What is the physical (i.e. non-mathematical) cause off the difference between a system of identical bosons and fermions?
quantum-mechanics
quantum-field-theory
pauli-exclusion-principle
Is it possible to construct a pure Bosonic creation operator in scalar QFT?
quantum-field-theory
hilbert-space
fourier-transform
second-quantization
How can there be vacuum quantum fluctuations of photons if they require electric charge to "see the light"?
quantum-field-theory
pair-production
Gupta-Bleuler and Lorenz Gauge: I don't understand the principle behind Gupta-Bleuler
quantum-field-theory
gauge-theory
quantum-electrodynamics
quantization
Gapless modes on both sides of the SFT/QFT correspondence
quantum-field-theory
statistical-mechanics
path-integral
partition-function