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

Undergrad Peter Woit's free QT, Groups and Representations ebook

  • Greg Bernhardt
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High School What Are Constrained Quantum States and Their Implications?

  • Trollfaz
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2

Undergrad Has Planck length been derived rigorously?

  • muzukashi suginaiyo
  • · Replies 9 ·
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9

High School Does an electron's position collapse when measuring g factor?

  • joegibs
  • · Replies 17 ·
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17

Undergrad If an electron isn't fundamental, what fields are it made of

  • joegibs
  • · Replies 3 ·
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3

Undergrad Extended hamiltonian operator for the Hydrogen atom

  • PedroBittar
  • · Replies 3 ·
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3

Undergrad Interpreting "momentum" in WKB approximation

  • deep838
  • · Replies 3 ·
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3

High School How can something be both a particle and a wave?

  • rahaverhma
  • · Replies 49 ·
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Undergrad Elementary particle transformations/couplings

  • stg213
  • · Replies 3 ·
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3

High School Is the passage of time caused by the rate of particle collapse from superposition?

  • Rachel Lee Pierce
  • · Replies 7 ·
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7

Graduate Deriving the Kubo Formula for Viscosity in Thermal Relativistic QFT

  • Kurret
  • · Replies 2 ·
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2

Undergrad What is (rest) mass for a particle?

  • calinvass
  • · Replies 3 ·
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3

High School Can tachyons be messenger particles between entangled particles?

  • Debaa
  • · Replies 25 ·
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25

Undergrad Berry phase mechanism in adiabatic anyon exchange

  • throneoo
  • · Replies 1 ·
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1

High School What’s the difference between TIQM and Time Symmetric QM? (a

  • thenewmans
  • · Replies 4 ·
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4

Undergrad Physical significance of a.σ in expectation -E(a.σ b.σ)?

  • N88
  • · Replies 82 ·
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82

Undergrad Position representation of the state of the system

  • fog37
  • · Replies 70 ·
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Graduate Deriving matrix element from Lagrangian

  • spaghetti3451
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1

Graduate Is the Effective Potential the same Quantum Potential?

  • vincequantum93
  • · Replies 1 ·
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1

Undergrad What is the physical meaning "without spin-orbit interaction

  • cytksu
  • · Replies 4 ·
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4

Undergrad Name for electron's trajectory outside of the orbit?

  • icakeov
  • · Replies 8 ·
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8

Undergrad First order perturbation derivation

  • spacetimedude
  • · Replies 6 ·
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6

High School What is the Quantum of Sound in Gases and Air

  • ThunderLight
  • · Replies 11 ·
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11

Undergrad Calculating Hamiltonian matrix elements in a chaotic system

  • Pyrus96
  • · Replies 1 ·
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1

Undergrad How is the order of events reversed in 1 trillion frames per second videos?

  • Ostrados
  • · Replies 12 ·
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12

Undergrad Why Don't L2 and Ly Commute When L2 and Lx Do?

  • dyn
  • · Replies 3 ·
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3

High School Entanglement measurements timing

  • Ostrados
  • · Replies 22 ·
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22

Undergrad Does femtosecond light pulse experiment support Schrödinger's cat?

  • bodycode
  • · Replies 24 ·
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24

Graduate Are two models with the same S matrix directly related by their parameters?

  • gonadas91
  • · Replies 3 ·
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3

Undergrad Are quantum fields unobservable if their expectation value is zero?

  • dm4b
  • · Replies 45 ·
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45

Undergrad Can quantum Zeno effect be applied to macroscopic systems?

  • Trollfaz
  • · Replies 1 ·
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1

Undergrad How is Graphene's Hamiltonian rotationally invariant?

  • Type1civ
  • · Replies 2 ·
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2

High School Untappable quantum communications?

  • GTOM
  • · Replies 7 ·
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7

Undergrad Is the spin linked to the third quantum number ?

  • Dinofou
  • · Replies 3 ·
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3

Undergrad Coherent Photons: Uncertainty and Locality

  • Marrrrrrr
  • · Replies 4 ·
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4

Undergrad Can the spin states of a spin1 particle be modeled?

  • edguy99
  • · Replies 4 ·
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4

Undergrad Is the particle in a 1-D infinite well doubly degenerate?

  • dyn
  • · Replies 7 ·
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7

Undergrad How can an atom change from ground to excited state?

  • ConfusedRookie
  • · Replies 18 ·
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18

Undergrad Entanglement, magnetic field and conservation law

  • Adel Makram
  • · Replies 15 ·
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15

High School Dirac Equation: Combining Quantum Mechanics and Special Relativity

  • cube137
  • · Replies 11 ·
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11

Graduate Scale invariant inverse square potential

  • hilbert2
  • · Replies 15 ·
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15

Undergrad Maxwell's Equation's From Klein Gordon

  • bhobba
  • · Replies 2 ·
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2

Undergrad How does nucleation work in cosmology?

  • Rodrigo Olivera
  • · Replies 1 ·
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1

Undergrad QFT operators time/space asymmetry?

  • TeethWhitener
  • · Replies 8 ·
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8

High School Quantum gravity and worldlines

  • cube137
  • · Replies 1 ·
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1

High School Wave particle duality - my visual/mental image

  • smsaks2000
  • · Replies 1 ·
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1

Undergrad Does measuring entangled spins on different axes break anti-correlation?

  • edguy99
  • · Replies 26 ·
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26

Graduate Understanding spin precession in a magnetic field

  • Tainty
  • · Replies 5 ·
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5

High School Can You Really Observe a Wave Function Without Collapsing It?

  • Debaa
  • · Replies 5 ·
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5

Undergrad Does the position operator act on wave functions as $\hat{x}|\psi\rangle$?

  • davidge
  • · Replies 14 ·
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14

Undergrad Orthogonality of Momentum Eigenstates: Why is ##\int e^{-ix}e^{2ix}dx=0##?

  • Isaac0427
  • · Replies 3 ·
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3

Graduate Photon angular momentum and magnetic quantum number selection rules

  • Tainty
  • · Replies 30 ·
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Undergrad Matrix Mechanics and non-linear least squares analogy?

  • mike1000
  • · Replies 30 ·
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30

Undergrad Normalizing a Discrete Sum: Is the Wavefunction Fully Normalized?

  • Isaac0427
  • · Replies 2 ·
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2

Undergrad Does accelerating one momentum-entangled particle affect the other?

  • Ostrados
  • · Replies 15 ·
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15

Undergrad Thinking about the static electric field in terms of QFT

  • FallenApple
  • · Replies 10 ·
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10

Undergrad Understanding Scalar Quantity in Basic Bra-Ket Arithmetic

  • Vitani11
  • · Replies 18 ·
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18

Undergrad Lamb shift and the QFT vacuum....

  • asimov42
  • · Replies 3 ·
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3

Undergrad Given a Hamiltonian, finding the energy levels

  • Buggy Virus
  • · Replies 4 ·
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4

Undergrad Cgs or SI in quantum field theory?

  • nomadreid
  • · Replies 6 ·
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6

High School Double slit probability question

  • entropy1
  • · Replies 143 ·
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143

Undergrad Is E<mc^2 Critical for the Klein Paradox in Potential Step Analysis?

  • Joker93
  • · Replies 1 ·
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1

Graduate Can entangled photons explore black hole interiors?

  • Cindy Hops
  • · Replies 10 ·
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10

Undergrad The spin of the photon -- a weird experiment with a laser

  • donavi
  • · Replies 1 ·
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1

Graduate Deriving the Lagrangian from the Hamiltonian operator

  • redtree
  • · Replies 3 ·
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3

Undergrad What is the name for the "stuff" at heart of black hole?

  • Cindy Hops
  • · Replies 2 ·
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2

High School Does a particle have a conscience of its own?

  • Debaa
  • · Replies 3 ·
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3

Graduate Description of imaging through lens using quantized EM field

  • zxontt
  • · Replies 7 ·
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7

High School Finding total angular momentum eigenvalues for multi-particle spin systems

  • Lola1
  • · Replies 1 ·
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1

Undergrad Why quote the 10^120 vacuum energy discrepancy if cutoffs violate Lorentz invariance

  • asimov42
  • · Replies 3 ·
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3

Undergrad A question from reading Feynman's book on QED

  • mike1000
  • · Replies 15 ·
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15

Undergrad Deriving Spherical Harmonics from Sakurai's Book

  • davidge
  • · Replies 12 ·
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12

Undergrad Position and Momentum are random variables in QM?

  • mike1000
  • · Replies 4 ·
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4

Undergrad Article on Quantum Bootstrapping and Geometric Theory Space

  • jedishrfu
  • · Replies 1 ·
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1

High School Wavelength of Particles Moving at 1m/s

  • Daniel Petka
  • · Replies 2 ·
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2

Undergrad What Do Elements in the Quantum Probability Formula <Ψ|P|Ψ> Represent?

  • mike1000
  • · Replies 7 ·
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7

Undergrad Does a Delta Potential Barrier Allow for Bound Solutions?

  • dyn
  • · Replies 1 ·
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1

Undergrad Photon and electron phase in polarization and interference

  • Talisman
  • · Replies 2 ·
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2

Undergrad Proof that parity operator is Hermitian in 3-D

  • dyn
  • · Replies 16 ·
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16

High School Can Quantum Linked Signals Be Observed in Real-Time in Space?

  • Brad Jamison
  • · Replies 5 ·
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5

Undergrad Conservation of energy in quantum measurement

  • maline
  • · Replies 40 ·
2
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40

Graduate Why the inside of a box is coherent

  • Binax011
  • · Replies 4 ·
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4

Undergrad Entanglement versus non-interacting multi-particle systems

  • fog37
  • · Replies 18 ·
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18

Graduate Mathematical formulation of local non-realism

  • greypilgrim
  • · Replies 5 ·
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5

High School Quantum Tunneling and Heat Distribution in Laser Cavities?

  • Daniel Petka
  • · Replies 7 ·
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7

High School Funneling Light to an Electron: A Size Challenge

  • gmalcolm77
  • · Replies 1 ·
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1

Undergrad What is the speed of decoherence and its predictions for coherent systems?

  • Binax011
  • · Replies 8 ·
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8

Undergrad Do I have the correct form for the number of states, the |n>?

  • rocdoc
  • · Replies 14 ·
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14

Undergrad About general solutions to Schrodinger equation

  • betelgeuse91
  • · Replies 13 ·
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13

Undergrad Is Light a Particle or a Wave in Different Contexts?

  • qnach
  • · Replies 4 ·
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4

High School Rest Energy - Kinetic Energy

  • orangepeelsnice
  • · Replies 3 ·
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3

Undergrad Extending an infinitesimal operator

  • davidge
  • · Replies 4 ·
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4

Graduate Is the electron a fundamental particle?

  • Ostrados
  • · Replies 3 ·
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3

Undergrad What is the Wave Function and How Does it Compare to the Schrodinger Equation?

  • Xilus
  • · Replies 3 ·
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3

Undergrad Is the Planck Length the Ultimate Limit of Measurement?

  • nomadreid
  • · Replies 5 ·
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5

Undergrad Why does the Dirac equation act on a 4-component spinor?

  • Milsomonk
  • · Replies 2 ·
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2

Undergrad Does the Uncertainty Principle restrict a particle's path?

  • mike1000
  • · Replies 29 ·
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29

Undergrad Built an HBT Interferometer but don't get the physics

  • Mellowed
  • · Replies 1 ·
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1

Undergrad Which ψ do I use for the Expectation Value ?

  • SpaceNerdz
  • · Replies 3 ·
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3

Undergrad How to synthesize quantum circuits?

  • nashed
  • · Replies 1 ·
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1