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9

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1

answer

177

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+100

Is there no mode expansion for $:e^{i k_\mu X^\mu(z, \bar z)}:$ in the free boson CFT?

quantum-field-theory string-theory conformal-field-theory

modified yesterday and008 51

2

votes

1

answer

88

views

+50

Derive vacuum polarization and magnetization

quantum-electrodynamics

answered Feb 25 at 15:42 John Donne 4,208

2

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0

answers

48

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+50

Light by light cross section using equivalent photon approximation (EPA)

quantum-field-theory scattering computational-physics scattering-cross-section

modified Feb 25 at 19:15 CStarAlgebra 1,380

4

votes

5

answers

293

views

+100

Special Relativity - Reference Frames $S$ and $S'$

special-relativity reference-frames inertial-frames

modified yesterday Young Kindaichi 4,631

3

votes

1

answer

94

views

+50

Diagrammatic representations of generating functionals $Z[J]$, $W[J]$, and $\Gamma[\varphi]$

quantum-field-theory resource-recommendations feynman-diagrams partition-function 1pi-effective-action

answered 2 days ago Richard Myers 2,486

7

votes

4

answers

184

views

+50

Why do wet papers create no sound at all?

acoustics material-science vibrations

answered 2 days ago Sagar Gorijala 39

2

votes

2

answers

221

views

+400

Why a falling object has a constant acceleration?

newtonian-mechanics forces mass acceleration free-fall

modified yesterday user1379857 5,374

1

vote

0

answers

69

views

+50

Average of Two successive momenta $m\frac{x_{k+1}-x_k}{\epsilon}m\frac{x_k-x_{k-1}}{\epsilon}$ using rules of path integral

quantum-mechanics field-theory path-integral greens-functions propagator

modified 11 hours ago Lonitch 97

5

votes

2

answers

173

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+200

Physics of the Planche

newtonian-mechanics forces torque statics biology

modified yesterday Plonker 21

5

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4

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267

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+50

Are fundamental forces, forces or net forces?

forces electrostatics electric-fields intuition

modified 17 mins ago GRAVITON PI 535

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