User Wild Feather

4 votes

3 answers

890 views

Is the parity operator an observable?

asked Jun 12, 2020 at 8:23

4 votes

3 answers

157 views

Why do free-falling particles converge onto the Hubble flow?

asked Jan 8, 2023 at 13:39

4 votes

3 answers

206 views

Change of variables from FRW metric to Newtonian gauge

asked Jun 1 at 16:03

3 votes

0 answers

302 views

Dirac delta in Fourier space for finite volume

asked Jun 13, 2023 at 10:02

2 votes

1 answer

134 views

Why is cosmological time unique?

asked Jan 12, 2023 at 10:12

2 votes

1 answer

100 views

Concept of distance in cosmology

asked Jan 13, 2023 at 14:23

2 votes

1 answer

269 views

Poisson equation in universe with gravity and expansion

asked Jul 24, 2023 at 18:42

2 votes

2 answers

5k views

Expected value of linear momentum with real wave function

asked Feb 1, 2021 at 9:40

2 votes

1 answer

96 views

Why are the distances in real space and Fourier space inverses of each other?

asked Feb 21 at 18:22

1 vote

0 answers

116 views

Gravitational potential for concentric spherical shells

asked May 17, 2023 at 18:13

1 vote

1 answer

147 views

Dimensionless power spectrum

asked Oct 6, 2022 at 19:10

1 vote

2 answers

3k views

Variation of resistance with temperature in semiconductors

asked Oct 18, 2017 at 16:46

1 vote

1 answer

182 views

Different definitions of recession velocity

asked Jan 19, 2023 at 9:50

1 vote

2 answers

233 views

Continuity equation for the conservation of energy from the conservation of the energy-momentum tensor

asked Jan 27, 2023 at 10:24

1 vote

2 answers

275 views

Upper index covariant derivative $\nabla^\mu$

asked Feb 2, 2023 at 18:39

1 vote

1 answer

1k views

Compute density of states in momentum space and in phase space

asked Feb 11, 2023 at 19:54

1 vote

0 answers

52 views

Contraction of distances in explanation of relativity of simultaneity in special relativity

asked Mar 9, 2023 at 10:09

1 vote

1 answer

103 views

How to express symmetry of a mixed (1,1) tensor with upper and lower index?

asked Mar 15, 2023 at 10:24

1 vote

1 answer

278 views

Poisson equation in Cosmology at first order in perturbation theory

asked Jul 26, 2023 at 8:25

1 vote

2 answers

441 views

How to obtain the continuity and Euler equations by taking moments of the Vlasov equation in Cosmology?

asked Oct 16, 2023 at 16:49

1 vote

0 answers

31 views

Fourier coefficients of fluid velocity in Cosmology

asked Nov 24, 2023 at 13:06

1 vote

0 answers

96 views

Momentum in terms of comoving velocity in cosmology

asked Aug 27, 2023 at 19:41

1 vote

1 answer

76 views

Sign convention for the Lagrangian of a free massive point particle in general relativity

asked Sep 15, 2023 at 17:14

1 vote

1 answer

239 views

How to express the linear growth equation in Cosmology in terms of $\partial_a$

asked Oct 5, 2023 at 16:42

1 vote

1 answer

155 views

Fourier transform of the top-hat filter [closed]

asked Jul 12, 2023 at 13:45

1 vote

1 answer

310 views

Explanation for the value of the Hubble radius

asked Apr 10, 2023 at 9:15

1 vote

0 answers

93 views

Spatial and temporal derivatives of a perturbation

asked Apr 18, 2023 at 10:13

0 votes

1 answer

359 views

Calculation about two-point correlation function in Fourier space

asked May 8, 2023 at 18:11

0 votes

1 answer

104 views

Calculating distance from the FRW metric

asked Jan 17, 2023 at 18:54

0 votes

0 answers

39 views

Why is it true that $\mathcal{H}'\vec{x}=-\vec{\nabla}\phi_b$?

asked Oct 10, 2023 at 12:56

Stack Exchange Network

41 Questions

Is the parity operator an observable?

Why do free-falling particles converge onto the Hubble flow?

Change of variables from FRW metric to Newtonian gauge

Dirac delta in Fourier space for finite volume

Why is cosmological time unique?

Concept of distance in cosmology

Poisson equation in universe with gravity and expansion

Expected value of linear momentum with real wave function

Why are the distances in real space and Fourier space inverses of each other?

Gravitational potential for concentric spherical shells

Dimensionless power spectrum

Variation of resistance with temperature in semiconductors

Different definitions of recession velocity

Continuity equation for the conservation of energy from the conservation of the energy-momentum tensor

Upper index covariant derivative $\nabla^\mu$

Compute density of states in momentum space and in phase space

Contraction of distances in explanation of relativity of simultaneity in special relativity

How to express symmetry of a mixed (1,1) tensor with upper and lower index?

Poisson equation in Cosmology at first order in perturbation theory

How to obtain the continuity and Euler equations by taking moments of the Vlasov equation in Cosmology?

Fourier coefficients of fluid velocity in Cosmology

Momentum in terms of comoving velocity in cosmology

Sign convention for the Lagrangian of a free massive point particle in general relativity

How to express the linear growth equation in Cosmology in terms of $\partial_a$

Fourier transform of the top-hat filter [closed]

Explanation for the value of the Hubble radius

Spatial and temporal derivatives of a perturbation

Calculation about two-point correlation function in Fourier space

Calculating distance from the FRW metric

Why is it true that $\mathcal{H}'\vec{x}=-\vec{\nabla}\phi_b$?