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 Spherical Harmonics from operator analysis

  • davidge
  • · Replies 13 ·
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13

Undergrad Absorption rate on a quantised EM field

  • brunow
  • · Replies 1 ·
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1

Undergrad Checking My Understanding: Lagrangian & Path Integral Formulation

  • redtree
  • · Replies 6 ·
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6

Undergrad Is Entropic Uncertainty Principle taken seriously in QM?

  • LarryS
  • · Replies 1 ·
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1

Undergrad Revisiting Heisenberg's Uncertainty Principle: Is There Room for Improvement?

  • chitranshgtm
  • · Replies 5 ·
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5

Graduate Gauge Theory: Principal G Bundles

  • nateHI
  • · Replies 10 ·
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10

Undergrad Why not calculate the "trajectory" of a wave function

  • zhouhao
  • · Replies 6 ·
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6

Undergrad Timelike Killing vectors & defining a vacuum state

  • Frank Castle
  • · Replies 27 ·
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27

Undergrad 'Normalisation' of Fourier Transforms in QFT

  • tomdodd4598
  • · Replies 1 ·
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1

Undergrad SO(2n) representation on n complex fields

  • hideelo
  • · Replies 4 ·
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4

Undergrad How is the CSCO in an harmonic oscillator?

  • Dario SLC
  • · Replies 6 ·
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6

Undergrad Why isn't the photon energy h nu over two?

  • DaveLush
  • · Replies 3 ·
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3

Undergrad Vector Operators in Quantum Mechanics: Adapting to Different Coordinate Systems

  • David Olivier
  • · Replies 37 ·
2
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37

Undergrad Can light be entangled in polarization and still exhibit interference?

  • Erik Ayer
  • · Replies 12 ·
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12

High School Photon producing Electron-Positron pair's effect on c.

  • abilolado
  • · Replies 2 ·
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2

Graduate Constant Solutions of Real Scalar Field

  • hilbert2
  • · Replies 5 ·
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5

High School If energy increases with decreasing wavelength, then...

  • Sam_A
  • · Replies 3 ·
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3

Undergrad How does measurement work in a two particle universe?

  • FallenApple
  • · Replies 3 ·
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3

Undergrad Decoherence Pure States Into Mixed States

  • Electric to be
  • · Replies 2 ·
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2

Graduate Calculating Einstein's coefficients in QFT vs equilibrium

  • alemsalem
  • · Replies 11 ·
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11

Undergrad If electromagnetic waves propagate, do photons as well?

  • calinvass
  • · Replies 7 ·
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7

Undergrad How do we interpret an EM wave using Quantum Mechanics?

  • calinvass
  • · Replies 7 ·
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7

Undergrad Questions about the Dirac delta

  • Isaac0427
  • · Replies 26 ·
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26

Undergrad Two-Level Atom Driven by Two Lasers?

  • Twigg
  • · Replies 0 ·
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0

High School Is Light a Wave or a Particle? Understanding Its Nature and Travel to Our Eyes

  • Quantum Velocity
  • · Replies 4 ·
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4

High School Heisenberg applied to accelerated particles

  • Chorlton
  • · Replies 4 ·
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4

Undergrad Spherical Harmonics: Arriving at Equation

  • davidge
  • · Replies 10 ·
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10

Undergrad Actual example of a mixed state not part of entangled state

  • Rainbows_
  • · Replies 26 ·
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26

High School Terry Tao's Interesting View of QM

  • bhobba
  • · Replies 1 ·
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1

Undergrad Quantum entangled image sensor for space camera-telescope

  • Thelonious Monk
  • · Replies 5 ·
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5

Undergrad Experimental history of quantum physics

  • manu de hanoi
  • · Replies 7 ·
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7

Undergrad How does sequential measurement affect observable data in molecules?

  • Rainbows_
  • · Replies 7 ·
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7

Undergrad Similar behavior between anti-particles and waves?

  • despues357
  • · Replies 2 ·
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2

Graduate Discrete measurement operator definition

  • jim jones
  • · Replies 2 ·
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2

High School QFT for Beginners: Operators & Their Physical Significance

  • Wrichik Basu
  • · Replies 25 ·
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25

Graduate What Hilbert space for a spinless particle?

  • David Olivier
  • · Replies 44 ·
2
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44

High School How much space does a single photon occupy?

  • Peter Mason
  • · Replies 47 ·
2
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47

High School Measuring momentum and position in particle colliders

  • Sophrosyne
  • · Replies 12 ·
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12

Undergrad Establishing consistency between a wave model of the photon and a particle model

  • Charles Link
  • · Replies 6 ·
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6

Undergrad (QED) The initial mass and the correction cancelling out

  • Christian
  • · Replies 20 ·
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20

Undergrad Hamiltonian in Quantum vs Classical

  • Electric to be
  • · Replies 40 ·
2
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40

High School Why don't emission/loss of virtual photons lower a charge's energy?

  • Ahsan Khan
  • · Replies 2 ·
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2

Undergrad (Conceptual) Infinity energy via quantum tunneling & Nuclear Fusion?

  • Ethan Singer
  • · Replies 7 ·
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7

Undergrad Lorentz transformation and its Noether current

  • Ken Gallock
  • · Replies 6 ·
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6

High School What is Quantum Spin? Understanding Basics

  • Quantum Velocity
  • · Replies 10 ·
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10

Undergrad Radiative collapse of an electron in a classical atom

  • LauritsT
  • · Replies 6 ·
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6

Undergrad Fermi's golden rule derivation

  • -marko-
  • · Replies 1 ·
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1

Undergrad Do quantum fluctuations mean metric fluctuations?

  • nomadreid
  • · Replies 1 ·
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1

High School Delayed Choice Quantum Eraser - Experimental Details

  • albroun
  • · Replies 2 ·
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2

High School Can an atom be in two places at once?

  • Habib_7654
  • · Replies 5 ·
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5

Undergrad Determinant problem in an article about QCD phase diagram

  • Ken Gallock
  • · Replies 4 ·
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4

High School About electrons and the photoelectric effect

  • rareEarthminerals
  • · Replies 2 ·
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2

High School Is there any state of matter colder than solid?

  • Quantum Velocity
  • · Replies 10 ·
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10

Undergrad Quantum Teleportation: Exploiting Entanglement & No Cloning Theorem

  • Trollfaz
  • · Replies 5 ·
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5

Undergrad Deductions of Formulas for Energy

  • cazador970
  • · Replies 2 ·
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2

Insights Struggles with the Continuum - Part 7 - Comments

  • john baez
  • · Replies 2 ·
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2

Undergrad Energy-time versus time bin DOF

  • Armchair
  • · Replies 8 ·
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8

Undergrad What does the 0-ket in this state function expression represent?

  • davidge
  • · Replies 3 ·
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3

High School Does Momentum Affect Potential Energy in a Particle Box?

  • mieral
  • · Replies 41 ·
2
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41

Undergrad Where can I find textbooks and articles on relativistic Landau levels?

  • Ken Gallock
  • · Replies 1 ·
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1

Undergrad Path Integral in QM: Resolving Confusion on Causality

  • Silviu
  • · Replies 1 ·
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1

Undergrad Are QFT fields the medium for light?

  • FallenApple
  • · Replies 21 ·
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21

Undergrad Does Bra-Ket Notation Clarify the Gradient Operator in Quantum Mechanics?

  • christianmetzgeer
  • · Replies 11 ·
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11

Undergrad Do Hydrogen and Helium Electrons Share Identical Energy Quantums?

  • barryj
  • · Replies 16 ·
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16

Undergrad Potential terms in SE & Quantum Chemistry

  • mieral
  • · Replies 14 ·
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14

Undergrad Usage of partition function in derivation of Sackur-Tetrode

  • georg gill
  • · Replies 6 ·
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6

Undergrad A new approach: retrocausality in QFT

  • Buzz Bloom
  • · Replies 21 ·
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21

Graduate Similarity in form of time-evolution and Gibbs weight?

  • muscaria
  • · Replies 1 ·
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1

Undergrad Solving for <E^2> of a non-stationary state of the QSHO

  • hnicholls
  • · Replies 1 ·
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1

Undergrad Does a field operator always commute with itself?

  • Frank Castle
  • · Replies 2 ·
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2

High School The Dirac equation and the spectrum of the hydrogen atom

  • Sophrosyne
  • · Replies 10 ·
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10

Undergrad Bell's Inequality is only valid for non-negative numbers

  • harpo
  • · Replies 2 ·
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2

High School Quantum Entanglement & Special Relativity: BBC Report

  • Dr Wu
  • · Replies 2 ·
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2

Undergrad Just what is information, and what is its place in Nature

  • plschwartzx
  • · Replies 17 ·
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17

High School Double-slit experiment observed by split brain

  • Bojan Keevill
  • · Replies 9 ·
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9

Graduate Dyson's Formula from Tong's lecture notes

  • noir1993
  • · Replies 19 ·
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19

High School How does quantum entanglement protect a key?

  • gnnmartin
  • · Replies 4 ·
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4

Undergrad DeBroglie wavelength & particle-wave duality

  • Blue Scallop
  • · Replies 41 ·
2
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41

Undergrad What does it mean to span the Bloch sphere?

  • PieroC
  • · Replies 4 ·
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4

Undergrad Unruh effect in full spacetime

  • gerald V
  • · Replies 5 ·
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5

Undergrad Relationship between negative mass, energy and antimatter

  • martin25p2
  • · Replies 10 ·
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10

Undergrad Fourier transform and locality/uncertainty

  • bznm
  • · Replies 6 ·
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6

Graduate Field strength measurement and continuity

  • hilbert2
  • · Replies 8 ·
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8

Undergrad Representations of the Poincaré group: question in a proof

  • formodular
  • · Replies 9 ·
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9

Undergrad Why does "wave particle duality" not exist anymore?

  • Dadface
  • · Replies 39 ·
2
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39

Undergrad How do electrons impact the probability of fusion in a non-plasma fluid system?

  • Aidan Davis
  • · Replies 1 ·
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1

Undergrad Using measurement to extract energy?

  • nashed
  • · Replies 1 ·
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1

Graduate Srednicki's normalization choice for lie algebra generators

  • hideelo
  • · Replies 1 ·
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1

Undergrad Frustrated spontaneous emission

  • Trollfaz
  • · Replies 8 ·
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8

High School Classical physics emerging from quantum physics

  • Andrew Wright
  • · Replies 6 ·
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6

Graduate Scalar Fields with the Same Mass

  • hilbert2
  • · Replies 2 ·
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2

Undergrad Understanding the Mistake in Dirac's Hamiltonian for Field Quantization

  • Silviu
  • · Replies 4 ·
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4

High School Physical significance of wave function

  • Wrichik Basu
  • · Replies 4 ·
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4

Graduate Quantum telescope (different meaning)

  • nic30
  • · Replies 1 ·
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1

Undergrad Do Pions Exist Naturally in High Z Nuclei and How Do Their Half Lives Change?

  • Kevin McHugh
  • · Replies 4 ·
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4

Undergrad Are any electrons ejected below the threshold frequency?

  • lawlieto
  • · Replies 4 ·
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4

High School Do Instantaneous Reactions Imply Infinite Speed in Quantum Entanglement?

  • Deepak K Kapur
  • · Replies 17 ·
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17

Graduate Forming a unitary operator from measurement operators

  • Danny Boy
  • · Replies 2 ·
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2

High School If quantum particles can move to other universes, can macroscopic things move?

  • TheQuestionGuy14
  • · Replies 4 ·
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4

Undergrad Particle has certain energy levels in a potential well?

  • nickhobbs
  • · Replies 4 ·
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4