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 What is the Lamb-Dicke regime and how does it impact ion trapping experiments?

  • Nusc
  • · Replies 2 ·
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Graduate Stern-Gerlach Question: Can Interference be Seen?

  • msumm21
  • · Replies 12 ·
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12

Graduate Raising and lowering operators acting on spin 1 kets?

  • philip041
  • · Replies 3 ·
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3

Graduate Quantized vs. Continuous Variables

  • Tac-Tics
  • · Replies 11 ·
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11

Graduate Why Is the Uncertainty Principle Considered Strange?

  • mskaroly
  • · Replies 3 ·
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Undergrad Quantum physics vs classical physics

  • noobie!
  • · Replies 2 ·
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2

Graduate The Hilbert space of non-relativistic QM

  • Fredrik
  • · Replies 5 ·
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5

Graduate About momentum operator in other coordinate system

  • KFC
  • · Replies 1 ·
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1

Graduate Quantum Mechanics: Wave-Particle Duality & Paradox

  • tgt
  • · Replies 38 ·
2
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Graduate Direct Position Measurement on a Microscopic Scale with Twin Photons

  • newbee
  • · Replies 48 ·
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Graduate Spin ½ Particles: Turning Twice for Identical Results

  • Love*Physics
  • · Replies 15 ·
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Graduate Identical bosons vs. fermions in square potential well

  • bobshae
  • · Replies 2 ·
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Graduate Gauge Invariance: Classical vs Quantum

  • captain
  • · Replies 4 ·
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Graduate Pauli's Wave Mechanics text. h vs. hbar

  • Peeter
  • · Replies 2 ·
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2

Graduate Understanding the Dressed Particle Approach to Quantum Field Theory

  • spidey
  • · Replies 19 ·
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19

Graduate What is Quantum Theory and Why Do Electrons Orbit at Specific Distances?

  • quantum brain
  • · Replies 5 ·
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Graduate Product State Bra Order: Correct Form?

  • KFC
  • · Replies 2 ·
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2

Graduate Reflection and the measurement, and time irreversibility

  • Dmitry67
  • · Replies 2 ·
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2

Undergrad Why do we use short wavelength photons in Compton scattering?

  • KFC
  • · Replies 2 ·
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2

Graduate Does the calculated large cosmological constant in falsify QFT?

  • ensabah6
  • · Replies 6 ·
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6

Graduate Quantization and fluid mechanics?

  • quantumfireball
  • · Replies 7 ·
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7

Graduate Evaluating Feynman diagram in QFT without external fermion lines

  • Amanheis
  • · Replies 4 ·
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4

Graduate Understanding Energy Partition in Laser Cavity: Molecules vs. Radiation

  • Phrak
  • · Replies 11 ·
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11

Graduate Raising and lowering operators on a ket?

  • philip041
  • · Replies 18 ·
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18

Graduate Orders of magnutide in Heisenberg's uncertainty principle

  • Heirot
  • · Replies 3 ·
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3

Graduate The intense laser-atom physics and ionized electron

  • xylai
  • · Replies 7 ·
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7

Graduate Adjoint Operator: Use & Benefits

  • KFC
  • · Replies 9 ·
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9

Graduate Path Integral Doubt: How Did Shankar Deduce S/h>pi?

  • sumeetkd
  • · Replies 1 ·
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1

Graduate Heisenberg's Principle: Understanding Time & Energy

  • pi.rootpi
  • · Replies 3 ·
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3

Graduate Understanding Spin States in Quantum Mechanics

  • KFC
  • · Replies 2 ·
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2

Undergrad Basics of Quantum Chemistry, especially entanglement

  • darkmatter(s)
  • · Replies 5 ·
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Graduate Is a Photon Massless or Does it Have Relativistic Mass?

  • Nphysicist
  • · Replies 13 ·
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Graduate Operating on spin angular momenta

  • runninglow
  • · Replies 1 ·
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Graduate Pulsing a diode laser with very long pulses and very low repetition rates

  • r_daniel
  • · Replies 2 ·
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Graduate Two Identical Particles w/ Spin State s

  • degerativpart
  • · Replies 3 ·
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3

Graduate Born vs ABL Rules: How Do They Relate to Time Reversal in Quantum Mechanics?

  • Fredrik
  • · Replies 15 ·
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15

Graduate Greatest accuracy in the |mn> state is |n| = m

  • bra-kets
  • · Replies 2 ·
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Graduate Conjugate Variables: Uncertainty Relation Explained

  • spidey
  • · Replies 2 ·
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Graduate Question about the delta function

  • Fredrik
  • · Replies 1 ·
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Graduate Casimir Effect and Perpetual Motion

  • Zeteg
  • · Replies 16 ·
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Graduate Expectation value for radius of an electron in a hydrogen atom

  • emperrotta
  • · Replies 8 ·
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8

Graduate Older formulation of Pauli exclusion principle

  • kandhakumar
  • · Replies 2 ·
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2

Graduate Drawback of Hartree Product in Chemistry

  • kandhakumar
  • · Replies 2 ·
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Graduate Quantum Communication - Ideas & Solutions

  • McGarr
  • · Replies 10 ·
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10

Graduate Cavitation-does it relate to the Big Bang?

  • Earnest Stuar
  • · Replies 6 ·
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6

High School Looking for Layman's Physical Explanation for energy level in atoms

  • feynmann
  • · Replies 23 ·
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Graduate Does an electron have a makeup

  • ryn17
  • · Replies 72 ·
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Graduate Commutate relation of lowering operator and sperical tensor operators

  • Einsling
  • · Replies 1 ·
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Graduate What are the key misconceptions about quantum mechanics interpretations?

  • thenewmans
  • · Replies 1 ·
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Graduate Stationary State: Energy & Time-Independent Wave Function

  • KFC
  • · Replies 5 ·
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Graduate Atom Shape: Experiments, Spheres & Cubes in Physics

  • Chaos' lil bro Order
  • · Replies 30 ·
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Graduate Effects of the Variation of the Parameters of the Standard Model

  • Dmitry67
  • · Replies 2 ·
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Graduate What Is the Ground State of Bound Fermions in a Box?

  • Evgeny Naumov
  • · Replies 11 ·
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Graduate Quantum Field Theory: Multiparticles and Single Particles

  • martyf
  • · Replies 2 ·
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2

Graduate Need a topic for paper in modern physics

  • dswatson
  • · Replies 7 ·
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7

Graduate Quantum Decoherence - how fast does it propagate?

  • Dmitry67
  • · Replies 15 ·
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Graduate Peskin - exponention of disconnected diagrams

  • PJK
  • · Replies 3 ·
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Graduate Uncertainty Principle: Photon Momentum & Universe

  • glueball8
  • · Replies 1 ·
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Graduate Question about quantization of scalar field

  • martyf
  • · Replies 1 ·
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Graduate Please shred my quantum physics-gravity worldview

  • lkubat
  • · Replies 13 ·
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13

Graduate Backwards Time Travel: Breaking the Heisenberg Principle?

  • Math Jeans
  • · Replies 31 ·
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Graduate Interference pattern given many which-path detectors?

  • gendou2
  • · Replies 2 ·
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2

Graduate Absorption Paradox: Continuous Photon Energies and Quantized Molecule Energies

  • p.tryon
  • · Replies 5 ·
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Undergrad Photon spin - experimental evidence

  • Usaf Moji
  • · Replies 6 ·
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6

Graduate Is Everything in the Universe Entangled According to Physics?

  • pallidin
  • · Replies 77 ·
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Graduate Do spontaneous and stimulated emission obey to a Boltzmann's statistics ?

  • fred_run
  • · Replies 6 ·
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Undergrad Photon Generation: Need for Electrical Current?

  • cam875
  • · Replies 34 ·
2
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Graduate How Does Aperture Size Affect Laser Beam Uncertainty?

  • fisico30
  • · Replies 4 ·
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4

Graduate WE theorem to evaluate matrix elements

  • pollo
  • · Replies 1 ·
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Graduate The physical meaning of Pauli Spin Matrices

  • gn0m0n
  • · Replies 16 ·
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Graduate Size does matter? Rayleigh scattering question

  • DeepSeeded
  • · Replies 1 ·
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1

Graduate Angular Momentum - Hydrogen (Quick Question)

  • mrjammin
  • · Replies 1 ·
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1

Graduate Conservation of momentum in QFT

  • jdstokes
  • · Replies 1 ·
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1

Graduate Vastness of space and infinite universes

  • bxadook
  • · Replies 3 ·
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3

Undergrad Problem in the Defination of electon's wavelength

  • soopo
  • · Replies 2 ·
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2

Undergrad Can Events with Zero Probability Actually Occur?

  • lax1113
  • · Replies 23 ·
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23

Undergrad No coupling of Photons with eletric fields

  • eintagsfliege
  • · Replies 3 ·
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3

Graduate Quantum Eraser and Delayed Choice Quantum Eraser

  • thenewmans
  • · Replies 1 ·
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1

Graduate Understanding the Basics of Psi(x) in Quantum Mechanics: Confusion Clarified

  • joker_900
  • · Replies 12 ·
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12

Graduate Prove Spinor Identity in Arbitrary Dimension

  • ismaili
  • · Replies 1 ·
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1

Graduate Does the Delayed Choice Experiment Challenge Classical Intuition?

  • debra
  • · Replies 1 ·
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1

Graduate Is Angular Momentum Quantized in a Free Electron's Non-Orbital Motion?

  • Eezekiel
  • · Replies 14 ·
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14

Graduate Wouldn't the Geiger Counter be considered a measuring device in SC?

  • esvion
  • · Replies 1 ·
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1

Undergrad Refraction - The lingering question

  • Burningmace
  • · Replies 12 ·
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12

Graduate Why 1D well must has this solution?

  • KFC
  • · Replies 6 ·
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6

Undergrad Narrow slits causes a diffraction pattern

  • Tac-Tics
  • · Replies 2 ·
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2

Graduate Calculating Inner Products of Spinors for QFT

  • CompuChip
  • · Replies 5 ·
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5

Graduate De Broglie Waves: Understanding Wave-Particle Duality

  • Vinu90
  • · Replies 1 ·
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1

Undergrad Why Does an Atom Experience Red and Blue Shifts During Its Journey?

  • cks
  • · Replies 2 ·
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2

Graduate Are Hilbert spaces uniquely defined for a given system?

  • diegzumillo
  • · Replies 2 ·
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2

Graduate Could positrons be electrons from the future traveling back in time?

  • ensabah6
  • · Replies 3 ·
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3

Graduate Classical vs Quantum Electromagetism

  • LarryS
  • · Replies 1 ·
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1

Graduate How useful would a metric independant basis be?

  • CPL.Luke
  • · Replies 3 ·
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3

Graduate How Does the Wavefunction Behave at an Infinite Potential Barrier?

  • ballzac
  • · Replies 4 ·
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4

Graduate Coherent States of the Quantum Harmonic Oscillator

  • arhanbezbora
  • · Replies 5 ·
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5

Graduate Complex conjugate of wave function

  • Amith2006
  • · Replies 4 ·
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4

Graduate Does collapse violate exchange symmetry?

  • Demystifier
  • · Replies 6 ·
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6

Graduate What does a single photon look like

  • quasar987
  • · Replies 34 ·
2
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Undergrad Question on electron orbitals and wavelengths?

  • Austin0
  • · Replies 16 ·
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16

Graduate Completeness of the Number States

  • afrano
  • · Replies 4 ·
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4