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 Are there any decoherance experiments someone could link to me?

  • batmanandjoker
  • · Replies 2 ·
Replies
2

Graduate What is the role of symmetry in quantum mechanics?

  • AndrewShen
  • · Replies 8 ·
Replies
8

Graduate Bell's theorem with spin-1/2 particles at 0, 45, 90, 135 degrees

  • jk22
  • · Replies 3 ·
Replies
3

Graduate Trying to understand Hermitian adjoint proof

  • Mary
  • · Replies 15 ·
Replies
15

Undergrad Double slit experimental method

  • zthompson47
  • · Replies 5 ·
Replies
5

Graduate What causes the repulsive force in diatomic molecules?

  • Runei
  • · Replies 2 ·
Replies
2

Graduate Simultaneously diagonalize two operators

  • kashokjayaram
  • · Replies 6 ·
Replies
6

Graduate Shifting integration variable when determing population densities

  • "Don't panic!"
  • · Replies 8 ·
Replies
8

Graduate Parition function for Boson gas with two quantum numbers

  • dipole
  • · Replies 2 ·
Replies
2

Undergrad Closing the Free Will Loophole: What to Expect

  • Jilang
  • · Replies 1 ·
Replies
1

Graduate Optical Tweezers experiment =]

  • BiGyElLoWhAt
  • · Replies 2 ·
Replies
2

Graduate Higgs field as the 5th fundamental force?

  • d-richard
  • · Replies 1 ·
Replies
1

Graduate A step in derivation of E-t uncertainty not clear

  • nomadreid
  • · Replies 6 ·
Replies
6

Graduate Can there be multiple ground states?

  • marc32123
  • · Replies 1 ·
Replies
1

Graduate How are atoms not in superposition if the electrons are

  • batmanandjoker
  • · Replies 10 ·
Replies
10

Graduate Commutators, mutual eigenkets, and observables

  • unscientific
  • · Replies 7 ·
Replies
7

Undergrad Less than one photon, what does it mean?

  • suma
  • · Replies 6 ·
Replies
6

Graduate Left hand side of the Schrödinger equation

  • mpv_plate
  • · Replies 16 ·
Replies
16

Graduate Why is a massless spin-2 automatically a graviton

  • Sonderval
  • · Replies 21 ·
Replies
21

Graduate Transition Rates / Squared Dirac Delta

  • MisterX
  • · Replies 2 ·
Replies
2

Graduate Theoretically predicting half-lives in particle physics

  • Moeen
  • · Replies 3 ·
Replies
3

Graduate What state do we have if we don't know if a measurement was performed?

  • greypilgrim
  • · Replies 20 ·
Replies
20

Graduate Are matrix element indices (row, column) or (column, row)?

  • LagrangeEuler
  • · Replies 2 ·
Replies
2

Graduate Why can't raising and lowering operators work for infinite square well?

  • LagrangeEuler
  • · Replies 12 ·
Replies
12

Graduate Klein Paradox - Dirac equation with step potentional

  • Drew Carey
  • · Replies 1 ·
Replies
1

Graduate Why do bound systems have less rest mass than the sum of its parts?

  • dimwatt
  • · Replies 5 ·
Replies
5

Graduate Is the Stern-Gerlach experiment sufficient?

  • intervoxel
  • · Replies 4 ·
Replies
4

Graduate Planck and Maxwell-boltzman distribution

  • Entanglement
  • · Replies 1 ·
Replies
1

Graduate Is this expression for the Dirac Lagrangian correct?

  • "Don't panic!"
  • · Replies 17 ·
Replies
17

Graduate Definition of a Gaussian wave packet for a Initial State

  • Gabriel Maia
  • · Replies 5 ·
Replies
5

Graduate Passing a black kole from double slit experiment setup

  • us40
  • · Replies 6 ·
Replies
6

Graduate The one-loop correction in Lehmann-Kallen form

  • JILIN
  • · Replies 7 ·
Replies
7

Graduate Inverse of unitary operator transformation for ladder operators

  • Hazzattack
  • · Replies 14 ·
Replies
14

Graduate Understanding Energy and Frequency in Rotation Spectra

  • unscientific
  • · Replies 5 ·
Replies
5

Graduate Understanding Standing Waves in Hydrogen with Animation and Quantum Mechanics

  • bobie
  • · Replies 4 ·
Replies
4

Graduate Understanding Spin-Orbit Interaction's Impact on Electron Energy Levels

  • bobie
  • · Replies 4 ·
Replies
4

Graduate The double slit experiment question?

  • masky007
  • · Replies 4 ·
Replies
4

Graduate Collapsing the wavefuntion to an Energy Eigenfunction?

  • mkarydas
  • · Replies 3 ·
Replies
3

Graduate Are Lasers Truly Examples of Quantum Coherent States?

  • Xyius
  • · Replies 18 ·
Replies
18

Graduate Laplace-Runge-Lenz vector problem

  • wantommy
  • · Replies 2 ·
Replies
2

Graduate Form of Solution to Schrodinger Equation

  • mrrelativistic
  • · Replies 5 ·
Replies
5

Graduate Heisenberg's Uncertainty or hidden variable

  • JohnLuck
  • · Replies 9 ·
Replies
9

Graduate Completeness of the eigenfunctions (Which vectorspace?)

  • Runei
  • · Replies 2 ·
Replies
2

Graduate One dimensional problems. More particles.

  • LagrangeEuler
  • · Replies 5 ·
Replies
5

Graduate Perturbation theory (the math)

  • Runei
  • · Replies 5 ·
Replies
5

Graduate What is the average value of an observable in a quantum system?

  • LagrangeEuler
  • · Replies 7 ·
Replies
7

Graduate Phase factors with eigenstates

  • Hazzattack
  • · Replies 8 ·
Replies
8

Undergrad Activity of photon during wavelegnth duration

  • acesuv
  • · Replies 3 ·
Replies
3

Graduate How Can Mixed States Be Prepared Beyond Decoherence?

  • naima
  • · Replies 17 ·
Replies
17

Graduate Is determinism truly at play in this scenario?

  • craigi
  • · Replies 54 ·
2
Replies
54

Graduate Why do two people see the same experimental results?

  • wmikewells
  • · Replies 38 ·
2
Replies
38

Graduate All eigenvalues of a Hermitian matrix are real

  • Isaac.Wang88
  • · Replies 3 ·
Replies
3

Graduate Fermi's golden rule for non-sinusoidal potentials like e^{-at}

  • MisterX
  • · Replies 6 ·
Replies
6

Graduate Graph States for Quantum Secret Sharing

  • limarodessa
  • · Replies 1 ·
Replies
1

Graduate Didn't understand what Sakurai meant by this.

  • M. next
  • · Replies 6 ·
Replies
6

Graduate Exact S-matrix for potential scattering

  • alemsalem
  • · Replies 1 ·
Replies
1

Graduate Diffraction accompanied with photoelectric effect

  • bgq
  • · Replies 6 ·
Replies
6

Graduate C-G coefficients by matrix method

  • M. next
  • · Replies 16 ·
Replies
16

Graduate The Relationship Between Wavelength and Amplitude of Photons and Electrons

  • bobie
  • · Replies 27 ·
Replies
27

Graduate Mean Occupation Number of Non-interacting quantum fluids

  • unscientific
  • · Replies 3 ·
Replies
3

Graduate Name of this relation, and struggle proving it.

  • M. next
  • · Replies 3 ·
Replies
3

Graduate What's up with the absorptive quantum eraser?

  • ab_gladsaxe
  • · Replies 5 ·
Replies
5

Graduate QFT (derivative the covariant and contravariant fields)

  • aams
  • · Replies 10 ·
Replies
10

Graduate Spin as internal angular momentum

  • Idoubt
  • · Replies 4 ·
Replies
4

Graduate Quantum Physics Science Advanced Project

  • The12thDoctor
  • · Replies 8 ·
Replies
8

Graduate Joint distribution of position and momentum

  • atyy
  • · Replies 6 ·
Replies
6

Graduate Understanding Spin Magnetic Field and its Direction in Relation to Charge Spin

  • M.Kalai vanan
  • · Replies 1 ·
Replies
1

Graduate Can Quantum States Be Deduced from a Density Matrix?

  • suma
  • · Replies 7 ·
Replies
7

Graduate Definition of Pointer in Measurement

  • SheikYerbouti
  • · Replies 2 ·
Replies
2

Graduate Simultaneous measuring of two operators

  • Caulfield
  • · Replies 4 ·
Replies
4

Graduate Fourier transform. Impulse representation.

  • LagrangeEuler
  • · Replies 1 ·
Replies
1

Graduate Is the Momentum Operator Hermitian in Quantum Mechanics?

  • dyn
  • · Replies 14 ·
Replies
14

Graduate Can Photon States Be Represented as Column Vectors in Quantum Mechanics?

  • suma
  • · Replies 1 ·
Replies
1

Graduate Changing the Hamiltonian without affecting the wave function

  • Isaac.Wang88
  • · Replies 1 ·
Replies
1

Graduate Normal ordering of two creation or annihilation operators

  • kashokjayaram
  • · Replies 3 ·
Replies
3

Graduate Quantum Mechanics without Measurement

  • stevendaryl
  • · Replies 286 ·
10
Replies
286

Graduate Partition Function, Grand Potential

  • unscientific
  • · Replies 2 ·
Replies
2

Graduate Calculating Probability of Field States in QFT

  • GarageDweller
  • · Replies 8 ·
Replies
8

High School Are electrons particles or waves?

  • sharnrock
  • · Replies 18 ·
Replies
18

Graduate Signs in the Field-Theoretic Euler-Lagrange Equation

  • Xezlec
  • · Replies 2 ·
Replies
2

Graduate What is the lowest rotational energy level for a diatomic molecule?

  • spaghetti3451
  • · Replies 2 ·
Replies
2

Graduate Why is the conductance quantized?

  • wdlang
  • · Replies 2 ·
Replies
2

Graduate Why do some particles couple to the Higgs field and others don't?

  • themadquark
  • · Replies 5 ·
Replies
5

Graduate Normal ordering versus no normal ordering

  • geoduck
  • · Replies 14 ·
Replies
14

Graduate Question on the 2-dim representation of the Lorentz group

  • Kontilera
  • · Replies 6 ·
Replies
6

Graduate How Do Eigenvalues Relate to Quantum Mechanics and Classical Physics?

  • CSOleson
  • · Replies 6 ·
Replies
6

Graduate What Causes Amplitude Changes in Light During Surface Interaction in QED?

  • NewChemTeache
  • · Replies 1 ·
Replies
1

Graduate Entanglement Swapping Superluminal Communication

  • burke142
  • · Replies 1 ·
Replies
1

Graduate The Extra Energy of a Doppler-Shifted Photon: Where Does it Go?

  • Zak
  • · Replies 2 ·
Replies
2

Undergrad Do electrons and nuclei rotate and vibrate in atoms?

  • M.Kalai vanan
  • · Replies 2 ·
Replies
2

Graduate What are some examples of non-commutating observables in quantum mechanics?

  • anorlunda
  • · Replies 6 ·
Replies
6

Graduate Destructive interference with different path lengths?

  • fleem
  • · Replies 8 ·
Replies
8

Graduate What is the first and second quantization?

  • Gabriel Maia
  • · Replies 3 ·
Replies
3

Graduate Can you calculate the commutator [V(x),p] in an infinite square well?

  • LagrangeEuler
  • · Replies 35 ·
2
Replies
35

Undergrad Does Heisenberg's uncertainty principle apply to classical measurements?

  • X_Art_X
  • · Replies 13 ·
Replies
13

Graduate On the classical action in Feynman approach

  • metroplex021
  • · Replies 3 ·
Replies
3

Graduate 'Largest' Schrodinger cat states created to date?

  • Gwinterz
  • · Replies 2 ·
Replies
2

Graduate Expectation value for momentum operator using Dirac Notation

  • sddang
  • · Replies 12 ·
Replies
12

Graduate Relativistic Quantum Mechanics?

  • Zak
  • · Replies 7 ·
Replies
7

Graduate What is the use of Dirac delta function in quantum mechanics?

  • manimaran1605
  • · Replies 8 ·
Replies
8