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 Uncertainty Principle in Wilson Cloud Chamber Measurements

  • LarryS
  • · Replies 1 ·
Replies
1

Graduate Is There a Classical Analogue of Spin Angular Momentum in Dirac Fields?

  • jostpuur
  • · Replies 17 ·
Replies
17

Graduate References or aids in learning QM?

  • physicsnoob93
  • · Replies 2 ·
Replies
2

Graduate About mixed state and pure state

  • ssampak
  • · Replies 6 ·
Replies
6

Graduate Wavefunction collapse and measurement

  • wduff
  • · Replies 2 ·
Replies
2

Graduate Resources for information on Entropy

  • LukeD
  • · Replies 2 ·
Replies
2

Graduate What is the wavefunction of the localized particle?

  • Jano L.
  • · Replies 10 ·
Replies
10

Undergrad Anti-Bonding/Bonding Molecular Orbitals

  • Tan PK
  • · Replies 8 ·
Replies
8

Graduate Proof of trace of density matrix in pure/mixed states

  • barnflakes
  • · Replies 11 ·
Replies
11

Graduate Eigenvalues of a reduced density matrix

  • barnflakes
  • · Replies 3 ·
Replies
3

Graduate How does a single photon interfere with itself in the double slit experiment?

  • cragar
  • · Replies 5 ·
Replies
5

Graduate Bell's Inequalities and Double Dependencies on Hidden Variables

  • inflector
  • · Replies 8 ·
Replies
8

Graduate Why does distance not affect quantum entanglement?

  • Fuji Katsuaki
  • · Replies 4 ·
Replies
4

Graduate Radiation by accelerating charge

  • paweld
  • · Replies 11 ·
Replies
11

Graduate Calculating Spinning Probabilities in Richard Feynman's QCD

  • zincshow
  • · Replies 2 ·
Replies
2

Undergrad Compton Scattering: What is the Difference from Electron-Photon Absorption?

  • luxiaolei
  • · Replies 4 ·
Replies
4

Graduate Recovering lagrangian from equations of motion

  • tulip
  • · Replies 4 ·
Replies
4

Graduate Does a photon's wavefunction permeate the universe immediately?

  • jnorman
  • · Replies 17 ·
Replies
17

Graduate Squaring the delta function in QFT(Srendicki ch11)

  • LAHLH
  • · Replies 7 ·
Replies
7

Graduate Why Does Weinberg Extend Energy Integration to Negative Infinity?

  • Yat-lo Lay
  • · Replies 17 ·
Replies
17

Graduate Can two photon emerage into one?

  • luxiaolei
  • · Replies 1 ·
Replies
1

Graduate Associativity problem with observables

  • zetafunction
  • · Replies 1 ·
Replies
1

Graduate Why do electrons repel and electrons attract protons in QED?

  • paweld
  • · Replies 3 ·
Replies
3

Graduate Quantum optics, 2 qubit gates acting on 2 qubits - cannot be factorized?

  • yaboidjaf
  • · Replies 2 ·
Replies
2

Graduate Zee QFT In a Nutshell Propagator Question

  • sheaf
  • · Replies 7 ·
Replies
7

Graduate Clarifying spin, angular momentum, and triplet states

  • luxiaolei
  • · Replies 1 ·
Replies
1

Graduate How can electrons in separate atoms share the same quantum numbers?

  • LostConjugate
  • · Replies 2 ·
Replies
2

Graduate Is the uncertainty principle a fundamental limit or measurement limitation?

  • lennybogzy
  • · Replies 22 ·
Replies
22

Graduate Planck black body formula question

  • telegraphic
  • · Replies 3 ·
Replies
3

Graduate Slit diffraction: time between emission and detection of photon

  • m.e.t.a.
  • · Replies 1 ·
Replies
1

Graduate What Causes 2n^2 Vacancies in Atomic Orbitals?

  • motoroller
  • · Replies 1 ·
Replies
1

Undergrad Do photons travel in straight lines?

  • johne1618
  • · Replies 4 ·
Replies
4

Graduate Calculating Effective Mass of InGaAs Alloy

  • daffoddill
  • · Replies 1 ·
Replies
1

Graduate Is There a Smallest Time Interval in the Quantum World?

  • Mr Peanut
  • · Replies 6 ·
Replies
6

Undergrad Are atoms and the universe structurally similar?

  • Ali Asadullah
  • · Replies 9 ·
Replies
9

Graduate Von Neumann entropy in terms of the tangle

  • barnflakes
  • · Replies 1 ·
Replies
1

Graduate Interpreting the probability distribution of the potential step

  • Identity
  • · Replies 7 ·
Replies
7

Graduate Relativistic Uncertainty Principle

  • LarryS
  • · Replies 5 ·
Replies
5

Undergrad Is the Momentum of a Photon Conserved in Matter?

  • tozhan
  • · Replies 7 ·
Replies
7

Undergrad What is electron spin and what does it do?

  • Char. Limit
  • · Replies 96 ·
4
Replies
96

Graduate Why Do These Quantum Mechanical Selection Rules Result in Zero?

  • sokrates
  • · Replies 18 ·
Replies
18

Graduate Peskin & Schroeder questions index and resources

  • Jimmy Snyder
  • · Replies 1 ·
Replies
1

Graduate Visualizing Electrons as Probability Densities

  • stevmg
  • · Replies 10 ·
Replies
10

Graduate Quantum / gauge field -> Classical limit

  • ansgar
  • · Replies 1 ·
Replies
1

Graduate Relativistic Mechanics of Hydrogen Like S Orbials at high Z

  • ChmDudeCB
  • · Replies 4 ·
Replies
4

Graduate What causes energy levels in atoms?

  • d-wat
  • · Replies 39 ·
2
Replies
39

Graduate Physical meaning of higher-dimensional Dirac matrices

  • eoghan
  • · Replies 1 ·
Replies
1

Graduate Is Geometric Quantum Mechanics a Viable Alternative to Hilbert Space?

  • Quadratrix
  • · Replies 2 ·
Replies
2

Graduate Information erasure without an energy cost

  • jimgraber
  • · Replies 1 ·
Replies
1

Graduate Feynman Diagrams for Exam Prep: Position vs. Momentum Space

  • madness
  • · Replies 5 ·
Replies
5

Graduate How Does Photon Spin Relate to Frequency and Polarization?

  • Prologue
  • · Replies 5 ·
Replies
5

Graduate How does a photon carry force?

  • FireBones
  • · Replies 60 ·
3
Replies
60

Graduate Schrodinger Equation: Kinetic Energy Impact?

  • HarryDaniels
  • · Replies 2 ·
Replies
2

Graduate Poisson bracket of canonical momentum and spatial field derivative

  • vertices
  • · Replies 14 ·
Replies
14

Graduate Is there an energy density limit before black hole formation?

  • flashprogram
  • · Replies 12 ·
Replies
12

Graduate Fermions with no mass, and helicity coupling.

  • IRobot
  • · Replies 1 ·
Replies
1

Graduate Are quarks really in isocoles triangle positions?

  • Puma
  • · Replies 1 ·
Replies
1

Graduate Can Energy and Interactions Create Electrons?

  • Moviemann345
  • · Replies 2 ·
Replies
2

Graduate How Does the Heisenberg Uncertainty Principle Challenge Classical Physics?

  • Rico L
  • · Replies 26 ·
Replies
26

Graduate New look at Youngs experiment

  • Iforgot
  • · Replies 8 ·
Replies
8

Graduate Where Does Charge Originate in Antimatter and Elementary Particles?

  • Leon_of_Vinci
  • · Replies 13 ·
Replies
13

Graduate Is the Photon a Unique Entity or a Chain of Energy Interactions?

  • madhatter106
  • · Replies 3 ·
Replies
3

Graduate Uniqeness of elemental particles

  • mark noble
  • · Replies 15 ·
Replies
15

Graduate Concervation of Momentum and Non-Classical Paths

  • JDługosz
  • · Replies 20 ·
Replies
20

Graduate QFT - interaction between field

  • paweld
  • · Replies 1 ·
Replies
1

Graduate Why does this integral go to zero?

  • vertices
  • · Replies 9 ·
Replies
9

Graduate Visualizing 6pz orbitals with Python and Mayavi

  • fk08
  • · Replies 1 ·
Replies
1

Undergrad About the excited state of an electron

  • oguz
  • · Replies 2 ·
Replies
2

Graduate Can someone explain this quantum physics concepts to me?

  • matthayzon89
  • · Replies 46 ·
2
Replies
46

Graduate How to Calculate Momentum using QM Completeness Relation?

  • luisgml_2000
  • · Replies 6 ·
Replies
6

Graduate Calculating weights of Feynman Diagrams

  • vertices
  • · Replies 5 ·
Replies
5

Graduate Why can't S_z equal zero if angular momentum is along the x or y axis?

  • LostConjugate
  • · Replies 13 ·
Replies
13

Graduate Experimental test of the Uncertainty principle

  • IRobot
  • · Replies 15 ·
Replies
15

Graduate Peskin Schroeder which chapter

  • Neitrino
  • · Replies 3 ·
Replies
3

Graduate Seperation of variables, infinite cubic well

  • student111
  • · Replies 2 ·
Replies
2

Graduate Physicists capture first images of atomic spin

  • Frzn
  • · Replies 1 ·
Replies
1

Graduate How can a photon carry electromagnetic force if photons have momentum?

  • scilover89
  • · Replies 8 ·
Replies
8

Graduate LS coupling for identical electrons

  • mk_gm1
  • · Replies 2 ·
Replies
2

Graduate Laplacian of 1/r in Darwin term

  • NanakiXIII
  • · Replies 3 ·
Replies
3

Graduate Time dependence of scalar product

  • Shredface
  • · Replies 2 ·
Replies
2

Undergrad Why Does Photomultiplier Tube Emit 2 Electrons?

  • SciencePF
  • · Replies 2 ·
Replies
2

Graduate Can infinite information be stored in nested spheres if volume equals surface area?

  • rrw4rusty
  • · Replies 1 ·
Replies
1

Graduate Can a Computer Generate Precognition Through Positron Experimentation?

  • rhenretta
  • · Replies 4 ·
Replies
4

What aspects of quantum mechanics interest you most?

  • Aki
  • · Replies 20 ·
Replies
20

Undergrad Electron energy increases with N?

  • diagopod
  • · Replies 9 ·
Replies
9

Graduate Normalised wavefunction to calculate the expectation

  • roshan2004
  • · Replies 5 ·
Replies
5

Graduate The radius of an electron orbit in helium

  • Kennalj
  • · Replies 11 ·
Replies
11

Graduate Schrodinger Time Dependent equation

  • HarryDaniels
  • · Replies 3 ·
Replies
3

Graduate Why doesn't energy expectation value depend on time for a particle in an infinite well?

  • Master J
  • · Replies 6 ·
Replies
6

Graduate What does 'Nothing' mean to a quantum physicist?

  • pctopgs
  • · Replies 21 ·
Replies
21

Graduate Really basic quantum mechanics question

  • barnflakes
  • · Replies 1 ·
Replies
1

Graduate What is the physical reason for the speed of light paradox?

  • Jean Paul
  • · Replies 11 ·
Replies
11

High School Is 'The Secret Law of Attraction' considered quantum physics? Do you support it?

  • matthayzon89
  • · Replies 7 ·
Replies
7

Graduate Radial probability density / quantum numbers.

  • adwodon
  • · Replies 4 ·
Replies
4

Graduate Overlap integrals in quantum harmonic oscillator problems

  • randybryan
  • · Replies 1 ·
Replies
1

Graduate Why does Σ¹ = 2iγ²γ³ from the Levi-Civita commutator formula?

  • vertices
  • · Replies 2 ·
Replies
2

Graduate Quantum Suicide Theory = Everyone Dies Of Old Age?

  • Marglar7
  • · Replies 13 ·
Replies
13

Graduate How Can Degenerate Fermi Gases Illuminate Quantum Statistics?

  • PRodQuanta
  • · Replies 1 ·
Replies
1

Graduate Allowed energies for electrons in hydrogenic atoms

  • manenbu
  • · Replies 2 ·
Replies
2

Graduate Is this an error in Srednicki?

  • LAHLH
  • · Replies 1 ·
Replies
1