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 Quantum Optics wave amplitude question

  • Master J
  • · Replies 1 ·
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Graduate Quadrupole-quadrupole interaction?

  • neo143
  • · Replies 9 ·
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9

Graduate Are There Operators in Quantum Physics Without Eigenvalue Properties?

  • sancharsharma
  • · Replies 8 ·
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8

Graduate What does h.c. mean in Lagrangians?

  • hamiltonjr
  • · Replies 2 ·
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2

Graduate Wavelength of photon and size of imaged object

  • fred1234
  • · Replies 7 ·
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7

Undergrad What is the effect of photon-electron collisions in X-ray imaging?

  • genefalk
  • · Replies 24 ·
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24

Graduate What Are Propagators and Green's Functions in Quantum Mechanics?

  • Niles
  • · Replies 4 ·
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4

Graduate Number of electron of a Hydrogen atom (molecule)

  • torehan
  • · Replies 8 ·
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8

Graduate Why Is Quantum Mechanics So Difficult to Understand?

  • y.moghadamnia
  • · Replies 5 ·
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5

Undergrad Entanglement and Teleportation

  • Nienstien
  • · Replies 1 ·
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Undergrad Was the relation between E and f known BEFORE quantum theory?

  • nonequilibrium
  • · Replies 8 ·
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Graduate Why is the beta decay electron spectrum continuous rather than discrete?

  • TrickyDicky
  • · Replies 3 ·
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3

Graduate Temporal symmetry solves all quantum paradoxes?

  • TheAlkemist
  • · Replies 90 ·
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Graduate Analysis and case study ideas for BB84 quantum cryptography

  • mumaga
  • · Replies 9 ·
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9

Graduate Etracting ZPP from the vacuum is in violation of the 1st law of thermodynamics?

  • jonnyk
  • · Replies 2 ·
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2

Graduate Thermal average of fermionic operators in equation 8.60

  • Niles
  • · Replies 3 ·
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3

Graduate Mapping Points on the Bloch Sphere

  • captainhampto
  • · Replies 5 ·
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5

Graduate What happens if two operators commute?

  • Master J
  • · Replies 2 ·
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2

Graduate Attosecond Tomography and Elephants

  • Joseph14
  • · Replies 1 ·
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1

Graduate How do we make sense of exponentiating an operator in quantum mechanics?

  • Chopin
  • · Replies 7 ·
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7

Graduate Why in Quantum Mechanics is about energy but no force

  • JayKo
  • · Replies 14 ·
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Graduate Interference pattern observed half-way into the formation

  • avarmaavarma
  • · Replies 1 ·
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1

Graduate Are virtual photons and electron-positron pairs related in the polarized vacuum?

  • TrickyDicky
  • · Replies 1 ·
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Graduate Does Collapsing a Wave Function Require Inputting Energy into a System?

  • Kidphysics
  • · Replies 27 ·
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27

Graduate Symmetries in Quantum Mechanics

  • LAHLH
  • · Replies 12 ·
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12

Graduate Questions concerning Delayed Quantum Eraser

  • jgm340
  • · Replies 7 ·
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7

Graduate Why Must Annihilation Occur Between Particle and Corresponding Antiparticle?

  • ndung200790
  • · Replies 1 ·
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Graduate What constitutes as a measurement?

  • Qentanglement
  • · Replies 8 ·
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8

Graduate How does time dependent perturbation theory apply to atomic physics?

  • jc09
  • · Replies 1 ·
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Graduate Energy levels for a different plancks constant

  • bhsmith
  • · Replies 14 ·
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Graduate Density Matrix (pure state) Property

  • Toten
  • · Replies 3 ·
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3

Graduate Understanding Schrödinger's Cat Experiment and the Many Worlds Interpretation

  • lj19
  • · Replies 37 ·
2
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Graduate Planck's Inspiration to Solve Blackbody Radiation

  • qbslug
  • · Replies 21 ·
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Graduate Commute Operators: Hi Niles - Find Out Now

  • Niles
  • · Replies 1 ·
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1

Graduate Spin, Anti-matter and all that jazz.

  • QEDrpf33
  • · Replies 8 ·
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8

Graduate How does interacting Lagrangian have form of product of fields?

  • ndung200790
  • · Replies 3 ·
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3

Graduate Grover's Algorithm/Superposition?

  • Bonham
  • · Replies 1 ·
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Graduate Who Can Apply the Operator on a Wave Function to Measure an Observable?

  • Joscha
  • · Replies 60 ·
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Graduate Energy: Discrete or Continuous

  • zlander79
  • · Replies 1 ·
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Graduate Does spin state remain constant without measurement?

  • Turtle492
  • · Replies 3 ·
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Graduate Symmetry factors (Srednicki, figure 9.11)

  • kexue
  • · Replies 4 ·
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4

High School If we saw x-ray waves could we see the inside of the objects?

  • egerol1
  • · Replies 3 ·
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Graduate Quantization of Klein-Gordon Field

  • go quantum!
  • · Replies 3 ·
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Graduate Weak Electron Interaction: Virtual Photon Effects?

  • scope
  • · Replies 6 ·
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6

Graduate What is the significance of the E/M ratio in modern physics?

  • sirous666
  • · Replies 3 ·
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3

Graduate Quantum Mechanics Questions: Superposition, Bohm Mechanics

  • StevieTNZ
  • · Replies 3 ·
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3

Graduate Is uncertainty in the Heisenberg principle one-dimensional or volumetric?

  • zeromodz
  • · Replies 1 ·
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Graduate Puzzled about electromagnetic field behaving like oscillators

  • commutator
  • · Replies 1 ·
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Graduate How does Srednicki derive equation 39.8 for the bar notation?

  • LAHLH
  • · Replies 18 ·
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Graduate Pauli exclusion principle between 2 identical fermions

  • scope
  • · Replies 2 ·
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Graduate What is the difference between left and right Weyl spinors in particle physics?

  • paweld
  • · Replies 6 ·
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Graduate Why the discrepancy in muonic H Bohr radius? 285 fm or 256 fm?

  • seattle.truth
  • · Replies 3 ·
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Graduate No uncertainty principle for scalar particles?

  • scope
  • · Replies 6 ·
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Graduate Ground state Bohr radius for muonic hydrogen

  • seattle.truth
  • · Replies 1 ·
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Graduate Is There a Contradiction in Weinberg's QFT Book on Simultaneous Eigenstates?

  • diraq
  • · Replies 8 ·
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Graduate Can Quantum Entanglement Solve the Mystery of Quantum Gravity?

  • bassplayer142
  • · Replies 5 ·
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Graduate Wavefunction really like a wave?

  • venton
  • · Replies 3 ·
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3

Graduate What Experiment Demonstrates the Particle Behavior of Electrons?

  • bhsmith
  • · Replies 3 ·
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Graduate What particles correspond to spin-3/2 and spin-2 representations of SO(3)?

  • kexue
  • · Replies 3 ·
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Graduate Difference between particle density and quantum density operators

  • Liao Chen
  • · Replies 3 ·
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3

Graduate Regarding normalization of the eigen basis vectors

  • ashokanand_n
  • · Replies 1 ·
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Graduate Is Space Quantized in Electromagnetic Fields?

  • jkg0
  • · Replies 4 ·
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4

Graduate Can I Calculate Traces and Cross Sections in QED Using Gamma Matrices?

  • ha.dnri
  • · Replies 1 ·
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Graduate Why does the Pauli X matrix differ in the Z and X bases?

  • quietrain
  • · Replies 16 ·
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16

Graduate Newton-Wigner operator for K-G filed

  • paweld
  • · Replies 1 ·
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1

Graduate Solving the Dirac Equation for the Hydrogen Atom

  • go quantum!
  • · Replies 2 ·
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2

Graduate An identity for functions of operators

  • Identity
  • · Replies 2 ·
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Graduate Questions about the Photoelectric Effect

  • Kidphysics
  • · Replies 7 ·
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7

Graduate Measuring one slit in double slit experiment

  • cryptist
  • · Replies 12 ·
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12

Graduate Deep space Communication hypothetical question

  • Panwasbipolar
  • · Replies 10 ·
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10

Graduate Can weak interaction be defined as a force related to distance between objects?

  • Khrapko
  • · Replies 5 ·
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5

Graduate Understanding Matter Waves and the de Broglie Hypothesis in Quantum Physics

  • TrickyDicky
  • · Replies 12 ·
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12

Graduate Worm Hole Idea: Electron talk at Great Distance

  • freydawg56
  • · Replies 1 ·
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1

Graduate Equalities for Paulimatrix averages

  • Funzies
  • · Replies 1 ·
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1

Graduate Proving af(a†)|n⟩ = df(a†)/da|0⟩ for annihilation operators

  • Shadowz
  • · Replies 18 ·
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18

Graduate Can centripetal force mediate graviton travel in spacetime?

  • ForceBoson
  • · Replies 4 ·
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4

Undergrad Difference between electron shells and orbitals

  • mariush
  • · Replies 8 ·
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8

Graduate Ryder, QFT, 1985, pg. 40, Eq. (2.69) K = sigma?

  • Living_Dog
  • · Replies 4 ·
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4

Graduate Proving eigenvalue of L_z squared cannot exceed eigenvalue of L^2

  • Funzies
  • · Replies 2 ·
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2

Graduate Displacement operator for coherent states?

  • Orbb
  • · Replies 11 ·
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11

Graduate The Hydrogen Atom (Schrodinger vs original Bohr theory)

  • aheizler
  • · Replies 1 ·
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1

Graduate Wave Formula by complex analysis

  • zerat2000
  • · Replies 1 ·
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1

Graduate Do N photons from both open slits give N1+N2 detections?

  • mitarbre
  • · Replies 4 ·
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4

Graduate Can Entangled Particles Still Show Interference in Quantum Experiments?

  • feizex
  • · Replies 1 ·
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1

Graduate Deck of Cards and Planck Time?

  • nicholasfouss
  • · Replies 3 ·
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3

Graduate Second Quantization: Explaining Creation/Annihilation Operator Transformation

  • Niles
  • · Replies 8 ·
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8

Graduate Probability of finding a state

  • quietrain
  • · Replies 4 ·
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4

Graduate Can't find that on the dictionary

  • go quantum!
  • · Replies 5 ·
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5

Undergrad Maximum detectable wavelength of a photoresistor

  • Rula
  • · Replies 2 ·
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2

Graduate Do Commuting Operators Always Share a Common Basis of Eigenvectors?

  • Funzies
  • · Replies 2 ·
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2

Graduate SU(2) spinor transformations and the role of ξ* in Ryder chapter 2

  • Living_Dog
  • · Replies 7 ·
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7

Graduate Is a Radio Wave Raser Feasible and How Would It Function?

  • ChrisAndre
  • · Replies 4 ·
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4

Undergrad Energy Levels: What Happens if First Level Contains More Than 2 Electrons?

  • ahiazaa
  • · Replies 2 ·
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2

Graduate Uncertainty principle and double-slit interference?

  • xylai
  • · Replies 40 ·
2
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40

Graduate Quantum Mechanics - Ritz variational principle

  • el_hijoeputa
  • · Replies 2 ·
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2

Graduate Decoherence over long distances - thought expt

  • Karl Coryat
  • · Replies 1 ·
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1

Graduate Is QM Phase Inherently Relativistic?

  • LarryS
  • · Replies 5 ·
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5

Graduate What means 'coherence' in quantum mechanics?

  • go quantum!
  • · Replies 2 ·
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2

Graduate Wavefunction of Macroscopic Objects

  • StevieTNZ
  • · Replies 1 ·
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1

Graduate Proving Unachievability of Absolute Zero: Uncertainty Principle

  • Archosaur
  • · Replies 4 ·
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4