Quantum Physics Forum

Join in expert discussion on quantum physics. Quantum physics is the mathematical description of the motion and interaction of subatomic particles. Quantum Mechanics and Field Theory.

Threads

Graduate What is the significance of the LSZ reduction formula in Srednicki's QFT book?

  • haushofer
  • · Replies 9 ·
Replies
9

Unreliable Sci-Fi Writer Attributes Quantum Flux

  • flatmaster
  • · Replies 3 ·
Replies
3

Graduate Why is a probe field necessary in pump-probe experiments?

  • KFC
  • · Replies 4 ·
Replies
4

Graduate Little fundamental question

  • facenian
  • · Replies 3 ·
Replies
3

Graduate Diffraction Grating Video (QED)

  • maverick_starstrider
  • · Replies 2 ·
Replies
2

Graduate Answer Me Precisely: Electronic Density Probability

  • Karrar
  • · Replies 5 ·
Replies
5

High School Cave of the Winds, CO - photons

  • neg entropy
  • · Replies 3 ·
Replies
3

Graduate Why Do Electromagnetic Interactions Involve Photons as Mediators?

  • tiny-tim
  • · Replies 2 ·
Replies
2

Graduate Is free will possible in Conway and Kochen's FW theorem?

  • Descartz2000
  • · Replies 4 ·
Replies
4

Undergrad Understanding Atom Excitation: Natural vs Triggered Movement and Photon Emission

  • wavingerwin
  • · Replies 3 ·
Replies
3

Are there any real quantum experiment videos available online?

  • maverick_starstrider
  • · Replies 10 ·
Replies
10

Graduate Question on function of operators

  • facenian
  • · Replies 6 ·
Replies
6

Graduate Are Quantum Boundaries Indefinite?

  • wittgenstein
  • · Replies 4 ·
Replies
4

Undergrad I really with spin quantum number.

  • Sunny09
  • · Replies 1 ·
Replies
1

Graduate Second Quantization: What Is It?

  • hagopbul
  • · Replies 1 ·
Replies
1

Graduate Wavefunction for particle inside a disk

  • lolgarithms
  • · Replies 13 ·
Replies
13

Undergrad Photoelectric Effect and light as a particle

  • Cmertin
  • · Replies 6 ·
Replies
6

Graduate Non-degenerate and degenerate perturbation theory

  • Lucien1011
  • · Replies 13 ·
Replies
13

Graduate Are virtual particles real or just mathematical tools?

  • wittgenstein
  • · Replies 5 ·
Replies
5

Graduate Energy, Time, Position, Momentum which is more fundamental?

  • compton
  • · Replies 4 ·
Replies
4

Graduate Fourier transform of a wave equation

  • mvillagra
  • · Replies 6 ·
Replies
6

Graduate The Energy Levels of a Quantum Harmonic Oscillator

  • mrausum
  • · Replies 2 ·
Replies
2
Replies
4

Graduate What is the relationship between temperature and emissive power for a gas?

  • lumberbunny
  • · Replies 1 ·
Replies
1

Graduate Why is the sum over all connected diagrams with a single source in QFT zero?

  • PJK
  • · Replies 6 ·
Replies
6

Graduate Isn't classical spin an instance of spin 1?

  • pellman
  • · Replies 3 ·
Replies
3

Graduate Spin 360 rotation - experiment

  • neworder1
  • · Replies 2 ·
Replies
2

Graduate Could Electrons Have an Internal Structure Beyond Fundamental Particles?

  • ghostanime2001
  • · Replies 6 ·
Replies
6

Graduate Is causality challenged by quantum theory's reliance on indeterminacy?

  • Borean
  • · Replies 56 ·
2
Replies
56

Graduate How Does Information Influence Quantum Particle Indistinguishability?

  • neworder1
  • · Replies 6 ·
Replies
6

Graduate Position and momentum operators in quantum field theory

  • pellman
  • · Replies 12 ·
Replies
12

Graduate How have breakthroughs in quantum mechanics been applied to real-world applications?

  • leftyguitarjo
  • · Replies 10 ·
Replies
10

Undergrad What Causes an Atom to be Unstable and More Prone to Radioactive Decay?

  • daisey
  • · Replies 25 ·
Replies
25

Undergrad What Is the Casimir Effect?

  • Benjamin113
  • · Replies 2 ·
Replies
2

Graduate Questions about variations on Double Slit experiment

  • underworld
  • · Replies 3 ·
Replies
3

Graduate Pertubation and density matrix

  • KFC
  • · Replies 2 ·
Replies
2

Undergrad How to make light act like a particle?

  • Cmertin
  • · Replies 1 ·
Replies
1

Undergrad Ionisation and the Photoelectrical Effect

  • Spud101
  • · Replies 3 ·
Replies
3

Graduate Hydrogen on one side, Helium on the other, and nothing in between ?

  • SimonA
  • · Replies 11 ·
Replies
11

Undergrad What CAUSES black cody radiation?

  • mahela007
  • · Replies 7 ·
Replies
7

Graduate What is the definition of a momentum *measurement*?

  • pellman
  • · Replies 2 ·
Replies
2

High School Do photons reflect off surfaces and what reflects them?

  • Spud101
  • · Replies 3 ·
Replies
3

Graduate How Is the Thickness of a Quantum Well Determined?

  • silentlamp
  • · Replies 1 ·
Replies
1

Graduate Does a Free Particle in Quantum Mechanics Have Constant Energy?

  • xcorat
  • · Replies 1 ·
Replies
1

Graduate Most accurate form of maxwell equations?

  • DeepSeeded
  • · Replies 10 ·
Replies
10

Graduate Spontaneous Symmetry breaking,phase factor

  • krishna mohan
  • · Replies 3 ·
Replies
3

Graduate Perpendicularity of quantuum states

  • markoX
  • · Replies 11 ·
Replies
11

Graduate Understanding X Quantum Gate: Act on |i> State?

  • markoX
  • · Replies 2 ·
Replies
2

Graduate Does the Born rule have implications for cosmology?

  • Count Iblis
  • · Replies 24 ·
Replies
24

Graduate Is Quantum Entanglement Just Correlation or a Real Physical Process?

  • PlayUK
  • · Replies 176 ·
6
Replies
176

Graduate Feynman diagram: incoming and outgoing particles

  • Dmitry67
  • · Replies 1 ·
Replies
1

Graduate Waves - bound and unbound states

  • quasar_4
  • · Replies 1 ·
Replies
1

Graduate Four momentum vector from energy-momentum-tensor

  • torus
  • · Replies 2 ·
Replies
2

Graduate Cassimir effect on a grand scale

  • Chaos' lil bro Order
  • · Replies 5 ·
Replies
5

Graduate Is there a paradox involving the Dirac equation and commutation with time?

  • ginda770
  • · Replies 1 ·
Replies
1

Graduate How does the Schrödinger equation lead to the QM theory of measurement?

  • LeonhardEuler
  • · Replies 6 ·
Replies
6

Graduate Can determinism survive quantum mechanics if outcomes are predetermined?

  • sftrabbit
  • · Replies 24 ·
Replies
24

High School Can energy be lost from a Photon?

  • Spud101
  • · Replies 16 ·
Replies
16

Graduate Black body radiation cavity with hole and thermal equilibrium

  • nietzsche
  • · Replies 8 ·
Replies
8

Graduate Can Virtual Particles in the Vacuum be Directly Detected?

  • AmyS7
  • · Replies 3 ·
Replies
3

Graduate Do non-local hidden variable theories account for Bose-Einstein condensates?

  • maverick_starstrider
  • · Replies 5 ·
Replies
5

Graduate Hardy's paradox in Bohm, Copenhagen, and MWI interpretations

  • Descartz2000
  • · Replies 8 ·
Replies
8

Graduate Faster-than-light communication

  • Albert V
  • · Replies 36 ·
2
Replies
36

Graduate Synthesis between Quantum Chaos and QFT.

  • MathematicalPhysicist
  • · Replies 3 ·
Replies
3

Undergrad How does the Electron get knocked off by a photon

  • raknath
  • · Replies 25 ·
Replies
25

Graduate What Is the Casimir Effect and Its Relation to Vacuum Energy?

  • eimos
  • · Replies 32 ·
2
Replies
32

Graduate Solution gross pitaevskii equation

  • dahaf
  • · Replies 1 ·
Replies
1

Graduate Does classical angular momentum conservation derive Planck's constant?

  • LarryS
  • · Replies 3 ·
Replies
3

Undergrad Why can't we see a laser beam in a perfect vacuum?

  • JSEverex
  • · Replies 5 ·
Replies
5

Graduate Why don't the Slits collapse the wave function?

  • kliide
  • · Replies 90 ·
4
Replies
90

Graduate Did photon obey Uncertainity Principle?

  • sndtam
  • · Replies 8 ·
Replies
8

Writing a science fiction novel

  • MrMyagi
  • · Replies 2 ·
Replies
2

Graduate Commutator of Position and Energy

  • meichenl
  • · Replies 2 ·
Replies
2

Graduate Antimatter interact with massive matter through gravity.

  • jweygna1
  • · Replies 3 ·
Replies
3

Graduate Particle collisions collapse wave function?

  • mordechai9
  • · Replies 2 ·
Replies
2

Graduate About Feynman rules for an external field

  • Sleuth
  • · Replies 2 ·
Replies
2
Replies
3

Graduate Is p²/2m the energy operator in momentum representation?

  • Geezer
  • · Replies 1 ·
Replies
1

Graduate Why does the Schrödinger cat paradox require the Copenhagen interpretation?

  • ArielGenesis
  • · Replies 103 ·
4
Replies
103

Graduate Does a Collision in Space Affect a Spaceship's Center of Mass Motion?

  • Count Iblis
  • · Replies 1 ·
Replies
1

Graduate Matter waves with zero momentum and single-slit diffraction

  • hotcommodity
  • · Replies 5 ·
Replies
5

High School Electron Orbits and Nuclei 2- Rotation vs Orbital Motion

  • Karrar
  • · Replies 74 ·
3
Replies
74

Graduate Simultaneous diagonalization and replacement of operators with eigenvalues ?

  • AxiomOfChoice
  • · Replies 1 ·
Replies
1

High School Does light have an electric charge?

  • gonegahgah
  • · Replies 2 ·
Replies
2

Graduate Generator of rotations rotations of WHAT?

  • AxiomOfChoice
  • · Replies 4 ·
Replies
4

Graduate Expectation of the Wilson Loop

  • Perturbation
  • · Replies 2 ·
Replies
2

Graduate Is 3s to 2s transition for Hygrogen forbidden?

  • SimonZ
  • · Replies 7 ·
Replies
7

Graduate Very elementary notation question

  • romistrub
  • · Replies 3 ·
Replies
3

Undergrad Uncertainty in simple harmonic oscilator

  • omri3012
  • · Replies 1 ·
Replies
1

Graduate Understanding UV/IR Terminology in Physics

  • ramparts
  • · Replies 4 ·
Replies
4

Graduate Why are electrons lighter but larger than quarks?

  • sidmontu
  • · Replies 6 ·
Replies
6

Graduate The Difference Between a Few Terms

  • Jilvin
  • · Replies 2 ·
Replies
2

Graduate Lorentz Algebra in Boosts for the spin-1/2 Dirac Field

  • maverick280857
  • · Replies 3 ·
Replies
3

Graduate Path Integrals in QED: Solve by Substituting Classical Solution?

  • RedX
  • · Replies 4 ·
Replies
4

Graduate A silly question I'm sure about Feynman's many paths

  • jaketodd
  • · Replies 62 ·
3
Replies
62

Graduate Moments in QM: When Can I Say JLS^2 Approx Equal JL+S?

  • Petar Mali
  • · Replies 5 ·
Replies
5

Graduate Uncertainty principle violation?

  • espen180
  • · Replies 4 ·
Replies
4

Graduate Quantum Tunneling - some silly thoughts

  • annatar
  • · Replies 3 ·
Replies
3

Graduate Parallel universes and the Quantum Field

  • MrMyagi
  • · Replies 2 ·
Replies
2

Undergrad Electron Phasepositive and negative?

  • rabbitweed
  • · Replies 2 ·
Replies
2