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 Artificial atoms used to improve compact discs?

  • underworld
  • · Replies 5 ·
Replies
5

Graduate In QM operators, why [YPz,YPx]=0, [ZPy,ZPy]=0 [X,Py]=0 [Y,Pz]=0, etc

  • mudyos
  • · Replies 10 ·
Replies
10

Graduate Time-dep perturbation theory

  • omyojj
  • · Replies 1 ·
Replies
1

Graduate How to work in the momentum representation?

  • pellman
  • · Replies 6 ·
Replies
6

Graduate Testing Hermiticity: How to Prove it?

  • Lorna
  • · Replies 2 ·
Replies
2

Graduate How do virtual photons mediate electromagnetic forces?

  • kcodon
  • · Replies 26 ·
Replies
26

Graduate Quantum physics with Green's functions

  • Tanja
  • · Replies 3 ·
Replies
3

Graduate Can a Quantum State Have Time-Dependent Eigenvalues?

  • pellman
  • · Replies 1 ·
Replies
1

Graduate System of hydrogen atoms in an electric field

  • Reid
  • · Replies 1 ·
Replies
1

Graduate Why are particles in quantum field theory discrete?

  • pellman
  • · Replies 24 ·
Replies
24

Graduate Why does spin 0 have to be a true scalar?

  • pellman
  • · Replies 28 ·
Replies
28

Graduate Can four-photon entanglement be a pure state like |HHH⟩ + |VVV⟩?

  • DrChinese
  • · Replies 16 ·
Replies
16

Graduate Does the Four Fermion Interaction Conserve Current Like Standard Models?

  • quantumfireball
  • · Replies 1 ·
Replies
1

Graduate Proving the Spin Half Nature of Dirac Quanta

  • quantumfireball
  • · Replies 7 ·
Replies
7

Graduate What is Quantum Physics and How Does it Differ from Classical Physics?

  • Lavace
  • · Replies 12 ·
Replies
12

Graduate Can Quantum Mechanics Allow for Discontinuous Wavefunctions and Probabilities?

  • Loren Booda
  • · Replies 4 ·
Replies
4

Graduate Non-Commutative Angular Momentum, and Muonium

  • YouWish
  • · Replies 1 ·
Replies
1

Graduate A crank's idea about Uncertainty Principle

  • neelakash
  • · Replies 27 ·
Replies
27

Graduate Probability Amplitude phases

  • Frankww
  • · Replies 3 ·
Replies
3

Graduate How can a single-frequency photon be a wave packet?

  • wawens
  • · Replies 7 ·
Replies
7

Graduate Nonlocality of a single particle without objections

  • Ivan Seeking
  • · Replies 6 ·
Replies
6

Graduate Intiutive approach to Green's function for SE

  • gulsen
  • · Replies 1 ·
Replies
1

Graduate Entanglement: Can We Logically Say a Body is in All Possible States?

  • Impulse2
  • · Replies 4 ·
Replies
4

Undergrad Multiple lines in H2 and Hg emission spectra

  • hagopbul
  • · Replies 1 ·
Replies
1

Graduate Hilbert/Fock space spanned by non-interacting states

  • smallphi
  • · Replies 13 ·
Replies
13

Graduate What exactly constitutes a gauge transformation?

  • captain
  • · Replies 3 ·
Replies
3

Graduate A contradiction of Heisenberg uncertainty principle?

  • AlbertEinstein
  • · Replies 29 ·
Replies
29

Graduate So, the question is: Can hidden variables explain quantum behaviour?

  • Enzoblue
  • · Replies 3 ·
Replies
3

Graduate Double slit variations: geometry, material, temperature, and neutral particles

  • PopcornKing
  • · Replies 2 ·
Replies
2

Graduate Spectral line width calculations

  • Mjolnir
  • · Replies 3 ·
Replies
3

Graduate Why are eigenstates important in the treatment of atomic systems?

  • Artaxerxes
  • · Replies 4 ·
Replies
4

Graduate Does closing one slit in the double slit experiment trigger Heisenberg uncertainty?

  • Dropout
  • · Replies 4 ·
Replies
4

Graduate Two particles in superposition

  • freerangequark
  • · Replies 6 ·
Replies
6

Undergrad Difference between flux and fluence

  • kolawole Bayowa
  • · Replies 1 ·
Replies
1
Replies
1

Graduate Can q Have Eigenvectors Other Than Zero in Standard Quantization Procedure?

  • kvl
  • · Replies 10 ·
Replies
10

Graduate Need a quick tutorial on the following topics

  • bochain
  • · Replies 5 ·
Replies
5

Graduate Deducing Degeneracy in Spin from Commutation Relations

  • Manchot
  • · Replies 2 ·
Replies
2

Graduate Does Absolute Zero Occur in the Universe?

  • dobroplayer
  • · Replies 13 ·
Replies
13

Graduate The Dirac Equation and the Neutrinos

  • Magister
  • · Replies 8 ·
Replies
8

Graduate Quantum Spin Chain Problem: An Overview

  • genloz
  • · Replies 4 ·
Replies
4

Graduate Fourier Transform of Hermitian Operators

  • BeauGeste
  • · Replies 4 ·
Replies
4

Graduate How Do I Derive the Zeta Function Using Zeta Function Regularization?

  • robousy
  • · Replies 5 ·
Replies
5

Graduate Understanding Non-Relativistic Path Integral Formulation

  • CPL.Luke
  • · Replies 5 ·
Replies
5

Undergrad Light through polarizing filters

  • clinchem
  • · Replies 8 ·
Replies
8

Graduate Is the physical whole a sum of quantum measurements?

  • Loren Booda
  • · Replies 1 ·
Replies
1

Graduate How Do Electrons, EM Waves, and Electricity Interact?

  • caybo
  • · Replies 7 ·
Replies
7

Graduate Why does the delta function well bind the particle when its energy is higher?

  • Poop-Loops
  • · Replies 7 ·
Replies
7

Graduate Can operators describe a single or many measurements simultaneously?

  • cscott
  • · Replies 1 ·
Replies
1

Graduate Communication using quantum entanglement

  • phsopher
  • · Replies 5 ·
Replies
5

Graduate What assumptions go into the 3D wave equation?

  • pardesi
  • · Replies 2 ·
Replies
2

Undergrad How do you visualize the transpose and adjoint of a Hermitian matrix?

  • nolanp2
  • · Replies 11 ·
Replies
11

Graduate How can the momentum be non-zero if the probability current density is zero?

  • neelakash
  • · Replies 2 ·
Replies
2

Graduate What is the use of representing wavefunctions as an exponential?

  • pardesi
  • · Replies 7 ·
Replies
7

Graduate Perturbation effect on harmonic osclillator

  • fahmed6
  • · Replies 6 ·
Replies
6

Graduate COM vs Lab Total energy discrepency

  • physmurf
  • · Replies 3 ·
Replies
3

Graduate How Does Quantum Theory Explain Repulsion Between Charged Balloons?

  • GTrax
  • · Replies 19 ·
Replies
19

Graduate Why Does a 2π Rotation Change the Sign of a Wavefunction in Quantum Mechanics?

  • neelakash
  • · Replies 5 ·
Replies
5

Graduate Calculating Group Velocity of Schrodinger Waves: Dispersion Relation

  • Euclid
  • · Replies 6 ·
Replies
6

Graduate Does Observing a Particle in Superposition Entangle You With It?

  • michael879
  • · Replies 65 ·
3
Replies
65

Graduate Is the collapse of the wavefunction in entangled particles instantaneous?

  • skihobbes
  • · Replies 2 ·
Replies
2

High School Direction of revolution of atomic electrons

  • armaronvinu
  • · Replies 1 ·
Replies
1

Undergrad Absorption of photons by electrons

  • Davnewil
  • · Replies 13 ·
Replies
13

Graduate Understanding Bound States in Quantum Mechanics

  • silimay
  • · Replies 7 ·
Replies
7

Graduate How Can You Have Negative Energy in a Positive Potential?

  • CPL.Luke
  • · Replies 5 ·
Replies
5

Graduate Typo in Kapusta or Ashok Das ? Formula for thermal propagator

  • Sunset
  • · Replies 1 ·
Replies
1

Graduate Euclidean QFT and thermodynamic analogy

  • OOO
  • · Replies 10 ·
Replies
10

Understanding How to Manage Your Finances

  • wdlang
  • · Replies 9 ·
Replies
9

Graduate Electromagnetic casimir effect

  • robousy
  • · Replies 1 ·
Replies
1

Graduate How two quantum systems interact ?

  • ronan1
  • · Replies 37 ·
2
Replies
37

Graduate Can QT estimate the ionization energy of neutral Helium, He I?

  • Sean Torrebadel
  • · Replies 30 ·
2
Replies
30

Graduate What Does Not Local in Space Mean in Relativistic Quantum Mechanics?

  • asub
  • · Replies 3 ·
Replies
3

Graduate Parity Operator, Symmetric Potential: Is V=PV?

  • fantispug
  • · Replies 2 ·
Replies
2

Graduate 'Spookytech'? Technology based on quantum interactions

  • sanman
  • · Replies 2 ·
Replies
2

Undergrad Do photoelectric electrons come from atomic nuclei?

  • Liger20
  • · Replies 14 ·
Replies
14

Graduate Transforming a Lorentz Scalar: psi-bar x psi x y_0

  • captain
  • · Replies 8 ·
Replies
8

Graduate Why doesn't a collapsed wavefunction collapse again in a different basis?

  • sridhar
  • · Replies 17 ·
Replies
17

Graduate Quick QM: Why Does Schrodinger Eq Being 1st Order Matter?

  • Thrice
  • · Replies 5 ·
Replies
5

Graduate Pψ=aψ and wave function uniqueness

  • mengsk
  • · Replies 5 ·
Replies
5

Graduate Orthonormal basis and operators

  • friend
  • · Replies 15 ·
Replies
15

Graduate Is wavefunction collapse an axiom or can it be derived?

  • lalbatros
  • · Replies 32 ·
2
Replies
32

Graduate Usefulness of Heisenberg picture?

  • Manchot
  • · Replies 11 ·
Replies
11

Graduate How does Helium-4 exhibit bosonic properties despite being composed of fermions?

  • Iamu
  • · Replies 6 ·
Replies
6

Graduate Angular Momentum Ladder Operators

  • masudr
  • · Replies 2 ·
Replies
2

Graduate Photon, black hole, Wikipedia quote

  • pdxjjb
  • · Replies 5 ·
Replies
5

Graduate How can one ensure Lorentz invariance when using an external field in QFT?

  • smileii
  • · Replies 5 ·
Replies
5

Graduate Are All Particles in Quantum Physics Excitations of Fields Like the Higgs Boson?

  • Coin
  • · Replies 4 ·
Replies
4

Graduate Can Energy Be Calculated from a Single Point in Full CI Calculations?

  • reddorange
  • · Replies 4 ·
Replies
4

Graduate How observation leads to wavefunction collapse?

  • Mr Virtual
  • · Replies 445 ·
15
Replies
445

Graduate How do bell states transform under a phase gate?

  • quantumlooser
  • · Replies 7 ·
Replies
7

Graduate Spin Interference: Looking for Thought Experiments with Single Electrons

  • msumm
  • · Replies 8 ·
Replies
8

Undergrad What Happens to a Particle's Energy When a 1D Box Shrinks?

  • msumm
  • · Replies 1 ·
Replies
1

Graduate Shor's algorithm giving high probability for period 0

  • michael879
  • · Replies 1 ·
Replies
1

Graduate Significance of the hamiltonian commuting

  • sridhar
  • · Replies 1 ·
Replies
1

Graduate Is the Ground State of a System Always Pure?

  • Physicist
  • · Replies 3 ·
Replies
3

Graduate Why don't entangled idler photons reveal which-path information in double slits?

  • bruce2g
  • · Replies 29 ·
Replies
29

Undergrad Are Atoms Affected by the Big Bang Theory?

  • ShadowWorks
  • · Replies 11 ·
Replies
11

Graduate On the helicity of the electrons

  • luisgml_2000
  • · Replies 1 ·
Replies
1

Graduate Symmetry and conserved probability current for wave functions

  • pellman
  • · Replies 33 ·
2
Replies
33

Graduate How are the positions of particles described in QFT?

  • vcdfrexzaswq
  • · Replies 25 ·
Replies
25