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 Pseudoparticle Operators: Fermion or Boson?

  • Gregory Gao
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Graduate Is the expectation value of momentum always zero for real wavefunctions?

  • dyn
  • · Replies 1 ·
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Graduate About diagonal element of dipole

  • KFC
  • · Replies 10 ·
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Graduate Effect of different atom on Compton Shift?

  • Seydlitz
  • · Replies 2 ·
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2

Graduate Most probable electron location in Hydrogen ground state

  • jaydnul
  • · Replies 20 ·
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Graduate Does Quantum Precession Contradict Traditional Spin Directions?

  • Jimmy87
  • · Replies 14 ·
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Graduate Frank-Condon Principle - Potential Energy Surfaces

  • elemis
  • · Replies 3 ·
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Graduate How Do Physicists Know That Quantum Superposition Does Exist?

  • pink laser
  • · Replies 18 ·
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Graduate Why Is the Wave Function Often Expressed as Psi = Cos(kr - wt) + i Sin(kr - wt)?

  • AL-Hassan Naser
  • · Replies 6 ·
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Graduate Heisenberg's Matrix Mechanics: An Understanding Review

  • Pollock
  • · Replies 3 ·
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Graduate Vector under Chiral transformation

  • PhyAmateur
  • · Replies 1 ·
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Graduate How Can a Hot, Vibrating Universe Remain Homogeneous?

  • acesuv
  • · Replies 1 ·
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Graduate Action corresponding to photon emission

  • semc
  • · Replies 1 ·
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Graduate Why Does an Operator in Quantum Mechanics Transform into a Matrix?

  • Jdraper
  • · Replies 3 ·
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Graduate Does electron has definite path?

  • Godparicle
  • · Replies 37 ·
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Graduate Superposition and retrocausality

  • Matush
  • · Replies 20 ·
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Undergrad Does every moving particle have a de Broglie wavelength?

  • gracy
  • · Replies 11 ·
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Graduate A Gedanken Experiment Regarding Bell's Theorem and Nonlocality

  • Gary Boothe
  • · Replies 1 ·
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Graduate Singlet and Triplet Terms misunderstanding

  • Eats Dirt
  • · Replies 2 ·
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Undergrad Double Slit Experiment and it's Results ?

  • kirsten_2009
  • · Replies 2 ·
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Graduate Who first theoretically determined the photon's spin value of 1

  • jjustinn
  • · Replies 16 ·
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Graduate The No Cloning theorem vs weak measurement

  • Checkster2323
  • · Replies 5 ·
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Undergrad Why does hydrogen gas absorb energy to excite electrons if it then emits photons?

  • gracy
  • · Replies 3 ·
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Graduate [QM] Conservation probability to degenerate eigenvalues

  • Saverio
  • · Replies 3 ·
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Graduate Localizing a high energy particle with momentum eigenstate superposition

  • Spinnor
  • · Replies 1 ·
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Graduate Associated Legendre differential equation involved in solving spin function?

  • bearcharge
  • · Replies 2 ·
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Graduate How do commutators derive the SO(2,1) Lie algebra from generators?

  • askalot
  • · Replies 3 ·
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Graduate About the photon carrying the electromagnetic forces

  • tonyxon22
  • · Replies 3 ·
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Graduate Wheeler-DeWitt and timelessness

  • nomadreid
  • · Replies 11 ·
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Graduate Polarization, Bell, and spin of photons

  • jk22
  • · Replies 6 ·
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Graduate Entangled Particles and the Hadron Collider?

  • KooperScooper
  • · Replies 8 ·
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Graduate Do fermionic operators on different subsystems commute?

  • gonadas91
  • · Replies 17 ·
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Graduate Spin 1 Particle Representations of SO(3) and SU(2)

  • LarryS
  • · Replies 4 ·
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Graduate Quantum scattering theory (lab frame, center of mass frame)

  • moriheru
  • · Replies 10 ·
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Graduate Why weak values can exceed the eigenvalue range of A

  • msumm21
  • · Replies 2 ·
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Graduate Dissipation in quantum mechanics

  • hokhani
  • · Replies 1 ·
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Graduate Description of the Electron Degeneracy Principle

  • realPhysics49
  • · Replies 1 ·
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Graduate What is the energy of a particle

  • jaydnul
  • · Replies 3 ·
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Graduate Finding solutions for combined 1D potentials with scattering states

  • morve
  • · Replies 1 ·
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Graduate Current of Complex scalar field

  • PhyAmateur
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Graduate Why is the integration range 2π to 0 in renormalization?

  • moriheru
  • · Replies 2 ·
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Graduate Solve Gauge Equiv. of Chern-Simons Action EOM

  • Maybe_Memorie
  • · Replies 1 ·
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Graduate Lower bounds on energy eigenvalues

  • jfy4
  • · Replies 3 ·
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3

High School Why does excess neutrons over protons make a nucleus unstable?

  • Fabian901
  • · Replies 5 ·
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Graduate What Constitutes a Quantum Measurement in Liquid Helium Experiments?

  • muppet
  • · Replies 2 ·
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Graduate What is the definition of future according to quantum mechanics?

  • amrani
  • · Replies 15 ·
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Graduate Spectrum of the Reduced matrix's eigenvalues

  • fpaolini
  • · Replies 1 ·
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Graduate How can I compute translation invariance for p in a one dimension wave function?

  • MickaelPC
  • · Replies 2 ·
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Graduate Calculating Expectation Value of Momentum with Fourier Transform

  • rwooduk
  • · Replies 2 ·
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Graduate In QM, can the trajectory in the phase-space split?

  • ORF
  • · Replies 7 ·
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Graduate Commuting operators require simultaneous eigenfunctions?

  • kmm
  • · Replies 25 ·
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Graduate What causes the weak interaction and what is its range?

  • mokeejoe5
  • · Replies 3 ·
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Graduate Can quantum indeterminacy affect macroscopic objects like falling stones?

  • Nick O
  • · Replies 5 ·
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Graduate Can Singlet Spin Pairs Behave Like Bosons?

  • anorlunda
  • · Replies 3 ·
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Graduate Can Wave Function Constants Be Both Positive and Negative?

  • terp.asessed
  • · Replies 5 ·
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Graduate Photonic density of state in matter

  • Jeffrey Yang
  • · Replies 2 ·
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Graduate How Does a Wave Packet Represent a Free Particle in Quantum Mechanics?

  • Waxterzz
  • · Replies 19 ·
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Graduate Quantum Teleportation - Misconceptions and QM fundamentals

  • Goodies1
  • · Replies 5 ·
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Graduate Proving an identity and some interesting maths stuff

  • gentsagree
  • · Replies 1 ·
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Graduate Renormalisation of the Schrodinger equation

  • spaghetti3451
  • · Replies 6 ·
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Graduate Information from the correlations

  • naima
  • · Replies 1 ·
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Graduate SU(3)-invariant Heisenberg XXX chain

  • Maybe_Memorie
  • · Replies 1 ·
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Graduate Why do particle beam relative velocities have consistent dimensions in this formula?

  • guest1234
  • · Replies 2 ·
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2

Graduate How do combination bands appear in vibrational spectra?

  • Talita
  • · Replies 1 ·
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Graduate Photon entanglement in type II spontaneous parametric down conversion

  • Clovis
  • · Replies 7 ·
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Graduate Is Planck's Law Based on Incorrect Assumptions About Boltzmann's Distribution?

  • Luck0
  • · Replies 9 ·
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Graduate Quantum objects and Electromagnetic waves

  • aditya ver.2.0
  • · Replies 13 ·
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Graduate Should the Normalization Constant be Positive or Complex?

  • kmm
  • · Replies 6 ·
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Graduate Is perturbation theory necessary for constructing quantum field theories?

  • the_pulp
  • · Replies 28 ·
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Graduate Quantum Mechanics Prior To The Big Bang

  • Dryson
  • · Replies 7 ·
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Graduate What is reality according to quantum mechanics?

  • Warpspeed13
  • · Replies 7 ·
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Graduate Exchange symmetry when adding angular momentum and in LS coupling?

  • CrimsonFlash
  • · Replies 3 ·
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3

Undergrad Electron transition notation should be simple

  • elegysix
  • · Replies 2 ·
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2

Graduate What does visibility mean in quantum interference?

  • suma
  • · Replies 3 ·
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3

Graduate Two slit electron diffraction / observer

  • Goodver
  • · Replies 1 ·
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1

Graduate Why does N fluctuate if the number operator commutes with the Hamiltonian?

  • Xemnas92
  • · Replies 38 ·
2
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Graduate Representing a bilinear functional as an inner product in Merzbacher 9.8

  • tigigi
  • · Replies 1 ·
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1

Graduate Advice for first time studying Quantum Mechanics ?

  • Ibrahim Hany
  • · Replies 6 ·
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Graduate When is |x|^μ in L2(-1,1) and how to learn Lebesgue spaces?

  • tigigi
  • · Replies 2 ·
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Graduate Evaluating Integrals of Exponential Functions with Dirac Delta

  • Dixanadu
  • · Replies 7 ·
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7

Graduate Quantum Imaging with Undetected Photons arXiv:1401.4318(quant phy)

  • Dadface
  • · Replies 8 ·
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8

Graduate Can there be non-trivial IR fixed points in asymptotically free theories?

  • geoduck
  • · Replies 1 ·
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1

Undergrad What are Einstein's 3 postulates for Photo electric effect?

  • uzman1243
  • · Replies 2 ·
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2

Graduate Hidden variable theories and Bell's theorem assumptions

  • miosim
  • · Replies 53 ·
2
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Graduate SU(2): Get RHS from LHS of Expression

  • intervoxel
  • · Replies 2 ·
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2

Graduate Nested Schrödinger's cat boxes with a hammer chain

  • moriheru
  • · Replies 20 ·
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20

Graduate How do you know the change in ml for a transition?

  • Jt00
  • · Replies 1 ·
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1

Graduate Analytical solution for bound state energies of infinite well

  • Bob007
  • · Replies 2 ·
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2

Undergrad Light remaining in a perfectly reflecting room after removal

  • doanr
  • · Replies 1 ·
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1

Graduate Fermi's Golden Rule Density of States

  • I<3NickTesla
  • · Replies 3 ·
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3

Graduate Emuberable and Demumerable sets

  • sweet springs
  • · Replies 8 ·
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Graduate Why does Dirac set m = 0.5ℏa for angular momentum magnitude 0.5ℏ?

  • jamie.j1989
  • · Replies 4 ·
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Graduate Efficiency of non-linear optical device

  • zhanhai
  • · Replies 3 ·
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3

Graduate Proving the Isomorphism Property of the Spinor Map in SL(2,C) and SO(3,1)

  • gentsagree
  • · Replies 2 ·
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2

Graduate The simplest derivation of position operator for momentum space

  • cryptist
  • · Replies 6 ·
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6

Graduate Understanding Scattering and Bound State Solutions in Quantum Mechanics

  • Logan Rudd
  • · Replies 1 ·
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1

Graduate How Should I Think About the Dirac Equation

  • bolbteppa
  • · Replies 13 ·
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Graduate Experimental Support of Shrodinger Equation

  • Hertz
  • · Replies 12 ·
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Graduate Divergence of the Stress-Energy Tensor

  • Paddyod1509
  • · Replies 4 ·
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4

Graduate RQM vs QM ( relativistic quantum mechanics vs quantum mechanics)

  • moriheru
  • · Replies 8 ·
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