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

High School The Spectral Gap and Quantum Vacuum Fluctuations

  • Cerenkov
  • · Replies 2 ·
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2

Undergrad Why does computing momentum for a superposed wave give imaginary result?

  • learn.steadfast
  • · Replies 20 ·
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20

Graduate Entangled wave function solved perturbatively

  • friend
  • · Replies 1 ·
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1

Graduate Finding expectation values of position and momentum for a Gaussian wave packet

  • bkmtkm
  • · Replies 2 ·
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2

Undergrad Period and probability density for a harmonic oscillator

  • Another
  • · Replies 2 ·
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2

Undergrad Space and time dependence of entangled particles

  • friend
  • · Replies 2 ·
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2

Undergrad Why does adding a detector eliminate interference in the double-slit experiment?

  • mk9898
  • · Replies 11 ·
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11

Graduate Why do particles have spin and what happens if they stop?

  • Kanishka Toshniwal
  • · Replies 31 ·
2
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31

Undergrad Wave function collapse in a double slit experiment

  • Sandeep T S
  • · Replies 6 ·
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6

Undergrad How close do electrons and positrons have to be to interact?

  • Cato
  • · Replies 4 ·
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4

Undergrad Why we do not need the total Lagrangian?

  • fxdung
  • · Replies 10 ·
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10

Graduate Quantum fields and the harmonic oscillator

  • Higgsono
  • · Replies 4 ·
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4

High School Why Do We See Distinct Lines in Atomic Emission and Absorption Spectra?

  • black hole 123
  • · Replies 17 ·
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17

Undergrad Hyperfine structure - Hamiltonian and bases

  • Teri
  • · Replies 1 ·
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1

Undergrad Is the electromagnetic field of an electron in QFT a real physical field?

  • Philipsmett
  • · Replies 11 ·
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11

Undergrad What is the significance of coupling in surface plasmons and plasmon polaritons?

  • Avardia
  • · Replies 1 ·
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1

Undergrad Polarization of light and probability

  • rasp
  • · Replies 17 ·
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17

Undergrad Understanding Redshift: The Role of Relative Motion between Emitter and Absorber

  • Harry17
  • · Replies 2 ·
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2

Undergrad Difference between preparing and measuring

  • rasp
  • · Replies 15 ·
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15

High School Can three-particle entanglement enable faster-than-light communication?

  • mataku
  • · Replies 56 ·
2
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56

Undergrad Multiplication of ladder-operators

  • Philip Land
  • · Replies 1 ·
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1

Undergrad Why can't two electrons occupy the same quantum state?

  • Quantum9999
  • · Replies 1 ·
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1

High School Entropy -- What exactly is it?

  • Levi Woods
  • · Replies 6 ·
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6

Graduate Green's function for the wave function

  • Higgsono
  • · Replies 1 ·
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1

Graduate Is the Fenna-Matthews-Olson complex a quantum dot?

  • Christopher Rourk
  • · Replies 1 ·
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1

Undergrad Does quantum entanglement depend on the chosen basis?

  • microsansfil
  • · Replies 37 ·
2
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37

Graduate Fermi-Dirac statistics, finding all electron configurations

  • sigint00
  • · Replies 3 ·
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3

Undergrad What is the common & connection of quantum entanglement and entropy?

  • Dhammika
  • · Replies 4 ·
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4

Graduate How to measure the first qubit in two qubit system? QC

  • Frank Schroer
  • · Replies 4 ·
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4

Graduate Fresnel Diffraction - Opaque Barrier Question

  • frederico
  • · Replies 6 ·
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6

Undergrad Phase and group velocity for a free particle

  • hokhani
  • · Replies 9 ·
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9

Undergrad Interference between an electron and a photon?

  • Sandeep T S
  • · Replies 11 ·
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11

High School Can a neutral pion contain a strange quark and anti-strange quark pair?

  • Quarkyguy
  • · Replies 4 ·
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4

Undergrad Does Multiplying Wavefunctions Affect Their Radius?

  • Bob Dylan
  • · Replies 5 ·
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5

High School Is the classical EM wave a single photon?

  • S Beck
  • · Replies 12 ·
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12

Undergrad Compound double slit with measurement on only one

  • Sting33
  • · Replies 20 ·
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20

Undergrad Schmidt decomposition and entropy of the W state

  • yamata1
  • · Replies 1 ·
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1

Undergrad Superposition of ortho and parahelium states

  • Rafael
  • · Replies 3 ·
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3

Undergrad Send the measurement device through a double slit

  • greypilgrim
  • · Replies 5 ·
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5

Graduate How can quarks exist if they are confined?

  • DarMM
  • · Replies 65 ·
3
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Graduate What is the role of Eve in a Man in the Middle attack?

  • Nur Ziadah
  • · Replies 6 ·
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6

Undergrad Why does classical wave energy theory fail to explain the photoelectric effect?

  • Sandeep T S
  • · Replies 6 ·
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6

Undergrad Diffracted photon/partice momentum

  • negative
  • · Replies 11 ·
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11

Graduate Seeking a derivation of Schrödinger's wave equation

  • gnnmartin
  • · Replies 12 ·
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12

Undergrad Hertz Experiment: Original Paper on Photoelectric Effect

  • Sandeep T S
  • · Replies 8 ·
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8

Undergrad The virtual photon can turn into a virtual electron positron?

  • Philipsmett
  • · Replies 6 ·
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6

Graduate Conserved currents from Standard Model symmetries before and after SSB

  • HomogenousCow
  • · Replies 6 ·
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6

Undergrad No interference if orthogonally polarized

  • greypilgrim
  • · Replies 2 ·
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2

Undergrad Photon detector on a dual slit experiment

  • rasp
  • · Replies 3 ·
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3

Undergrad The Uncertainty Principle - question within Griffiths' Text

  • Sparky_
  • · Replies 1 ·
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1

Undergrad Griffiths' Intro to Quantum Mechanics - primed variables

  • Sparky_
  • · Replies 10 ·
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10

High School Is radioactive decay truly random or just unpredictable?

  • JesW87
  • · Replies 5 ·
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5

Undergrad How to interpret the diffraction envelope

  • Bill Sellers
  • · Replies 4 ·
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4

Undergrad Are there proposed physical processes for superposition

  • rasp
  • · Replies 13 ·
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13

Undergrad What makes a field theory relativistic?

  • LarryS
  • · Replies 2 ·
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2

Undergrad Effect of Roughness on Cavity Resonator Spectrum

  • Swamp Thing
  • · Replies 2 ·
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2

Graduate Dipole, harmonic oscillator, and the coherent state

  • Karthiksrao
  • · Replies 3 ·
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3

Undergrad Light reflections between glass surfaces in Feynman's QED

  • Srihari05
  • · Replies 1 ·
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1

Undergrad Mathematics of Normalization in Physics

  • KurtLudwig
  • · Replies 4 ·
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4

Undergrad What happens to entanglement inside a polarizer?

  • boxfullofvacuumtubes
  • · Replies 4 ·
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4

Undergrad Can spacetime perturbation reveal which slit a photon passes through?

  • greypilgrim
  • · Replies 7 ·
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7

Undergrad Can a qubit have a finite number of ontic states in an epistemic model?

  • msumm21
  • · Replies 1 ·
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1

Graduate Causality and probability in QFT with real scalar fields

  • Aleolomorfo
  • · Replies 1 ·
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1

Undergrad Electron and virtual electron-positron pair

  • Philipsmett
  • · Replies 1 ·
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1

Undergrad Compton scattering in a Feynman diagram

  • nomadreid
  • · Replies 8 ·
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8

Graduate Heisenberg/Schrodinger pictures versus passive/active

  • Geofleur
  • · Replies 10 ·
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10

High School Can you measure a particle without breaking superposition?

  • TheQuestionGuy14
  • · Replies 4 ·
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4

Undergrad Can you measure a particle's speed over one Planck length?

  • InfiniteEntity
  • · Replies 5 ·
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5

Undergrad The allowed energies of a 3D harmonic oscillator

  • kkabi_seo
  • · Replies 3 ·
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3

High School UV catastrophe and photoelectric effect in gold leaf electroscope

  • Jimmy87
  • · Replies 1 ·
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1

Undergrad Do all TISE solutions for a finite barrier have either a or b zero?

  • Clara Chung
  • · Replies 5 ·
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5

Undergrad About spin precession in a magnetic field

  • Francisco Dahab
  • · Replies 4 ·
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4

High School Allowed and forbidden transitions

  • PainterGuy
  • · Replies 18 ·
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18

Undergrad Why are vector components conjugated in the inner product formula?

  • SebastianRM
  • · Replies 15 ·
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15

Undergrad Why is Lz quantized but Lx and Ly are not in hydrogen?

  • Rafael
  • · Replies 3 ·
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3

Graduate Representing harmonic oscillator potential operator in. Cartesian basis

  • Apashanka
  • · Replies 7 ·
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7

Undergrad Raising the ladder operators to a power

  • MooshiS
  • · Replies 3 ·
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3

Undergrad What is the difference between quantum field theory and quantum electrodynamics?

  • Philipsmett
  • · Replies 10 ·
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10

High School Have interference on single particles been mapped

  • Martyn Arthur
  • · Replies 4 ·
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4

Undergrad Transistors and Quantum Physics

  • Zeynel
  • · Replies 12 ·
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12

Undergrad Why are <dx/dt> and <dp/dt> 0?

  • EquationOfMotion
  • · Replies 14 ·
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14

Graduate Is there an additional assumption in the PBR theorem?

  • PeterDonis
  • · Replies 120 ·
5
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120

Undergrad Polarization and the beam splitter

  • Mentz114
  • · Replies 7 ·
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7

Undergrad Resolvent formalism in quantum mechanics

  • Konte
  • · Replies 7 ·
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7

High School So what is the new definition of the kilogram?

  • bbbl67
  • · Replies 63 ·
3
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63

Undergrad Why does the fermionic field have this time ordered contraction?

  • Avogadro Number
  • · Replies 3 ·
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3

Undergrad If the wave function is complex and the measurement is real

  • rasp
  • · Replies 4 ·
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4

Graduate Diagonalization of Hubbard Hamiltonian

  • Guilherme
  • · Replies 1 ·
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1

Undergrad Poles in Casimir force as function of frequency & mode

  • Swamp Thing
  • · Replies 2 ·
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2

Graduate Is there an uncertainty in energy measurement in quantum mechanics?

  • CGandC
  • · Replies 17 ·
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17

High School Are bosons always their own antiparticle

  • friend
  • · Replies 11 ·
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11

Undergrad How can laser photons have the same precise energy?

  • LarryS
  • · Replies 15 ·
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15

Undergrad Writing perturbed wave function

  • TheBlueDot
  • · Replies 1 ·
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1

Undergrad Accuracy of time dilation measurement *in principle*

  • bland
  • · Replies 9 ·
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9

Undergrad Thought experiment about superposition.

  • rasp
  • · Replies 3 ·
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3

High School How slow can Gedanken experiments be theoretically?

  • NTHstars
  • · Replies 9 ·
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9

Graduate Operators used without being explained

  • Technon
  • · Replies 4 ·
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4

Undergrad About the Schrödinger equation

  • Konte
  • · Replies 19 ·
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19

High School What Makes Two Identical Hydrogen Atoms Different?

  • Wondermine
  • · Replies 25 ·
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25

Undergrad Solution of Quantum differential equation

  • Edge5
  • · Replies 4 ·
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4