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

High School Entanglement when I "produce" positron-electron pairs one at a time

  • metastable
  • · Replies 46 ·
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Undergrad Confusion with Dirac notation in the eigenvalue problem

  • peguerosdc
  • · Replies 5 ·
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Graduate Rabi frequency and "optical resonance and two level atoms" by Allen

  • Paintjunkie
  • · Replies 7 ·
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Undergrad Planck had 2 definitions of energy in 1900, how?

  • Cool4Kat
  • · Replies 1 ·
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High School How do you find the Lagrangians for different fields?

  • Wrichik Basu
  • · Replies 1 ·
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Undergrad One vertex interactions in QED - error in the book?

  • Wrichik Basu
  • · Replies 4 ·
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4

High School Understanding Quantum: The Particle/Number Duality

  • Quotidian
  • · Replies 8 ·
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High School Do photons have a position operator and how is speed defined for them?

  • bahamagreen
  • · Replies 2 ·
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High School Quantum theory for high-school students

  • Demystifier
  • · Replies 77 ·
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Graduate Uncertainty vs Randomness in Quantum Physics

  • Sasho Andonov
  • · Replies 16 ·
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Undergrad A bar magnet and magnetic moment in a magnetic field

  • hokhani
  • · Replies 8 ·
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Undergrad Quantum Mechanics, The Delta-Function potential

  • eliUCV
  • · Replies 8 ·
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High School Fourier decomposition notation in QFT: 4-vector or 3-vector in exponents?

  • Wrichik Basu
  • · Replies 5 ·
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Undergrad Is the holographic principle based on fuzzy logic?

  • Suekdccia
  • · Replies 3 ·
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Undergrad Operations regarding tensor-product states

  • WWCY
  • · Replies 2 ·
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Undergrad Numerical solution to the Schrodinger eqn. using Finite Difference Method

  • patrykh18
  • · Replies 1 ·
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Graduate Time convolution master equation in Mohseni vs Breuer

  • Ark236
  • · Replies 1 ·
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Graduate Golden ratio fractal phase conjugation

  • Mieleko
  • · Replies 4 ·
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4

Undergrad Hund's rules and Pauli's principle

  • Reignbeaux
  • · Replies 6 ·
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6

Undergrad How can laser detuning excite an atom?

  • annaphys
  • · Replies 5 ·
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Graduate Why do we know that an elementary particle is a point particle?

  • fxdung
  • · Replies 30 ·
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Undergrad Particle in free space - what happens to the wave function after measurement?

  • QuasarBoy543298
  • · Replies 2 ·
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Graduate What are the units of the radial wavefunction in my FORTRAN code?

  • peanutbutter
  • · Replies 1 ·
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Graduate Time Evolution of a Square Pulse - Fourier

  • skynelson
  • · Replies 1 ·
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Undergrad Is Schrödinger's kittens thought experiment a genuine advance?

  • ftr
  • · Replies 31 ·
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Undergrad Quantum Jumps and Schrodinger's Cat are predictable

  • Tom.G
  • · Replies 79 ·
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High School Photon exchange in molecular bonds

  • Ocata
  • · Replies 2 ·
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Undergrad Is a particle really in superposition or just unknown?

  • thermia
  • · Replies 10 ·
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Graduate Is the wavefunction subjective? How?

  • fluidistic
  • · Replies 128 ·
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Undergrad Can Brain Responses to Quantum Signals Determine True Quantum Interpretation?

  • john taylor
  • · Replies 2 ·
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Undergrad Do spin operators 'appear' to commute for an entangled spin state?

  • muonion
  • · Replies 4 ·
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Undergrad Is there a procedure for designing some quantum circuits?

  • Haorong Wu
  • · Replies 2 ·
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Undergrad Uncertainty Principle in the context of tracking particle paths

  • WWCY
  • · Replies 12 ·
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Undergrad Communicating Via Quantum Entanglement Using Time Differentiated Pulse

  • ray3400
  • · Replies 24 ·
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Graduate Can the Huygens-Fresnel principle be translated into path integrals?

  • jordi
  • · Replies 14 ·
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Undergrad The Philosophy of Quantum Mechanics

  • A. Neumaier
  • · Replies 23 ·
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Undergrad Role of mass and quantum gravitational effects in friction?

  • IonReactor
  • · Replies 4 ·
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Graduate Observables when the symmetry is not broken?

  • mbond
  • · Replies 4 ·
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Undergrad Is the Basis in Quantum Physics a Fundamental Property of Objects?

  • jlcd
  • · Replies 15 ·
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Undergrad Why Would Observation Change Anything Physically?

  • ray3400
  • · Replies 24 ·
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Undergrad Why does a detector before the slits change the pattern in the double-slit experiment?

  • ray3400
  • · Replies 36 ·
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Insights Vacuum Fluctuations in Experimental Practice - Comments

  • A. Neumaier
  • · Replies 41 ·
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Graduate On the Planck Blackbody Function

  • Charles Link
  • · Replies 16 ·
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Undergrad Classicality and the Correspondence Principle

  • jlcd
  • · Replies 63 ·
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Undergrad Value of beta in Boltzmann Statistics taking degeneracy into account

  • JohnnyGui
  • · Replies 19 ·
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Undergrad How to know where the up and down spin go in the wavefunction?

  • QuarkDecay
  • · Replies 1 ·
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Graduate What is the significance of nonlocality super-activation in this paper?

  • DarMM
  • · Replies 1 ·
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Undergrad Does this hint of entanglement within protons suggest new physics?

  • member 656954
  • · Replies 2 ·
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Undergrad The information paradox and non-locality, ER = EPR

  • Dennis Plews
  • · Replies 6 ·
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Graduate What it is the internal space?

  • seletynof
  • · Replies 1 ·
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Graduate Someone observing Wigner and his friend

  • A. Neumaier
  • · Replies 20 ·
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High School Phase shift in Mach-Zehnder interferometer

  • Sonderval
  • · Replies 5 ·
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Undergrad Clebsch-Gordan coefficients for coupling three spin-1/2 particles

  • JoJoQuinoa
  • · Replies 3 ·
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Undergrad Explanation of spin degrees of freedom with respect to the x axis

  • Somali_Physicist
  • · Replies 9 ·
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Undergrad Attractive force of opposite charges by McIrvin

  • exponent137
  • · Replies 1 ·
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Undergrad D'Alembertian in Sakurai's Advanced QM book

  • Wrichik Basu
  • · Replies 10 ·
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Graduate Why is the metric tensor the unique choice for reducing tensor integrals?

  • gjj
  • · Replies 4 ·
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4

High School Loss of information and Quantum Determinism

  • Simple man
  • · Replies 26 ·
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Undergrad According to quantum physics, can our universe be a simulation?

  • Philipsmett
  • · Replies 3 ·
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Graduate Experimental evidence of non-local quantum forces

  • Auto-Didact
  • · Replies 3 ·
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Undergrad Entangle Distant Particles: Theoretical Possibility?

  • Curious marq
  • · Replies 1 ·
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Graduate Does the effective action make sense in Quantum Mechanics?

  • jordi
  • · Replies 5 ·
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High School Why does blue light mean hot but blue objects aren't hotter?

  • revv
  • · Replies 8 ·
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8

Graduate Deriving the midpoint in Weyl ordering for path integral propagators

  • TeethWhitener
  • · Replies 14 ·
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14

High School Are photons the wave sources of Huygens-Fresnel principle?

  • DoobleD
  • · Replies 8 ·
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8

Insights The Classical Limit of Quantum Mechanical Commutator

  • samalkhaiat
  • · Replies 8 ·
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Undergrad About the Feynman Path Integral and Principle of Least Time

  • EsbMtrx
  • · Replies 1 ·
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Graduate Influence of strong measurements in a Two Slit Interferometer

  • Marilyn67
  • · Replies 8 ·
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High School Double Slit Wave Interference With Single Electrons

  • metastable
  • · Replies 1 ·
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High School Was Bell's hypothesis verified?

  • jk22
  • · Replies 2 ·
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Undergrad Why does the orthogonal m=0 state carry s=0 in spin addition?

  • Sparky_
  • · Replies 14 ·
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Undergrad Viewing light at four trillion frames per second

  • zincshow
  • · Replies 3 ·
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3

Graduate Is the Klein-Gordon equation a quantization of classical particles?

  • jordi
  • · Replies 45 ·
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Undergrad Why does ρ(θ)dθ = ρ(x)dx for probability densities?

  • Kaguro
  • · Replies 6 ·
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6

High School Measuring a circle and the Uncertainty principle

  • brianhurren
  • · Replies 4 ·
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4

Undergrad Confusions about some symbols in QC

  • Haorong Wu
  • · Replies 4 ·
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4

Undergrad Relational Hidden Variables (Real ensemble or thermal?)

  • jlcd
  • · Replies 26 ·
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26

Undergrad Instantly reformable wave packets instead of "particles"?

  • Idunno
  • · Replies 17 ·
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17

High School "Slowly varying" potential for WKB approximation

  • Wrichik Basu
  • · Replies 1 ·
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1

High School Heisenberg's uncertainty principle - does it always apply?

  • DannyTr
  • · Replies 14 ·
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14

Undergrad Pauli spin matrices under inversion and 180 degree rotation?

  • zmth
  • · Replies 5 ·
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5

Undergrad Solving the Quantum Mechanics of a Hydrogen Atom

  • frustrationboltzmann
  • · Replies 3 ·
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3

Undergrad Electron wave funtion harmonic oscillator

  • jhonnyS
  • · Replies 2 ·
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2

Undergrad What Is the Correct Order for Multi-System Bra Vectors in Quantum Mechanics?

  • Talisman
  • · Replies 15 ·
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15

Undergrad Projection Operators: Pi, Pj, δij in Quantum Mechanics

  • RohanJ
  • · Replies 3 ·
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3

Undergrad How are apparently 'continuous' blackbody spectra formed?

  • argon1120
  • · Replies 4 ·
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4

Undergrad Fine Structure Spectra: Understanding Electron Intrinsic Spin Effects

  • zengodspeed1
  • · Replies 2 ·
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Graduate Are there conditions for the vanishing of geometrical phases in QM?

  • andresB
  • · Replies 1 ·
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1

Graduate Dipole moment operator and perterbations

  • Paintjunkie
  • · Replies 3 ·
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3

Undergrad Why does a photon have parity -1

  • Gene Naden
  • · Replies 7 ·
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7

Undergrad What is the failure of superposition in quantum mechanics?

  • Hawkingo
  • · Replies 8 ·
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8

Undergrad Are electromagnetic waves sine waves?

  • Jeff Root
  • · Replies 3 ·
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Graduate Crossing degeneracies and geometrical phases

  • andresB
  • · Replies 1 ·
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1

High School Potassium or other minerals and the photoelectic effect

  • pager48
  • · Replies 3 ·
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3

Undergrad Applying an observable operator on the current state

  • QuasarBoy543298
  • · Replies 3 ·
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3

Graduate Suppose there is an extra compact dimension, and suppose

  • Spinnor
  • · Replies 2 ·
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Graduate How to prove this property of the Dual Strength Field Tensor?

  • Gaussian97
  • · Replies 2 ·
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2

Graduate What does "solving a quantum mechanics problem" mean?

  • jordi
  • · Replies 3 ·
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3

Graduate Infinite Photons: How Can an Infinitesimal Time Range Create an Infinity?

  • JPC
  • · Replies 1 ·
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Undergrad Pauli matrices and shared eigenvectors

  • Sunny Singh
  • · Replies 3 ·
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