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 Why Do LS and jj Coupling Differ in Spectral Line Transitions?

  • bentzy
  • · Replies 12 ·
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12

High School Questions about Identical Particles

  • hgandh
  • · Replies 7 ·
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7

High School If electrons are waves, what causes them to change direction?

  • LSMOG
  • · Replies 8 ·
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8

Undergrad How can electrostatic fields be composed of photons?

  • fox26
  • · Replies 30 ·
2
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30

Graduate Why use continuous math in classical mechanics if reality is discrete

  • qttv
  • · Replies 12 ·
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12

Undergrad Making sure about the spreads in the Uncertainty Principle

  • fog37
  • · Replies 6 ·
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6

High School Spin and polarizations in momentum space

  • Azurite
  • · Replies 51 ·
2
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51

High School How far apart can electrons be and still violate the Pauli exclusion principle?

  • john t
  • · Replies 2 ·
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2

High School Do atomic nuclei transfer momentum to electron orbitals?

  • Vectronix
  • · Replies 3 ·
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3

High School Parity of two-particle state in coupled basis

  • hgandh
  • · Replies 3 ·
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3

High School Introduction to quantum physics and topological quantum matter

  • Arik Salehi
  • · Replies 4 ·
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4

Graduate Did nature or physicists invent the renormalization group?

  • Giulio Prisco
  • · Replies 6 ·
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6

Undergrad Why don't ground-state electrons fall into the nucleus?

  • drl
  • · Replies 4 ·
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4

High School What happens to things that aren't ever observed?

  • McNanners
  • · Replies 15 ·
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15

Undergrad Unruh temperature in gravitational field

  • jcap
  • · Replies 4 ·
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4

Graduate Fundamental Theorem of Quantum Measurements

  • Danny Boy
  • · Replies 77 ·
3
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77

Undergrad Macroscopic rotation from spin flipping?

  • Toothbrush
  • · Replies 13 ·
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13

Graduate What's the best quantum simulator?

  • skanskan
  • · Replies 9 ·
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9

Undergrad Gauge transformation and observable effects in the Aharanov-Bohm effect

  • Ghost Repeater
  • · Replies 7 ·
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7

Undergrad Can Optical Angular Momentum Revolutionize Open-Space Light Communication?

  • microsansfil
  • · Replies 3 ·
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3

Undergrad Can the Schrödinger equation be derived from classical wave assumptions?

  • snoopies622
  • · Replies 11 ·
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11

Undergrad Weinberg and Ray Transformations – Ch2 App A.

  • rocdoc
  • · Replies 1 ·
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1

Undergrad Operators and vectors in infinite dimensional vector spaces

  • fog37
  • · Replies 3 ·
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3

High School What Should You Research About Uncaused Quantum Events and Their Implications?

  • sayetsu
  • · Replies 10 ·
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10

High School Where Can I find the Einstein vs. Bohr Full Debates

  • learis
  • · Replies 24 ·
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24

Undergrad Reversible Measurement: Is It Possible?

  • A Puzzlement
  • · Replies 3 ·
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3

Undergrad Beam splitter in an entanglement swapping experiment

  • Mentz114
  • · Replies 12 ·
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12

Undergrad How small does a system have to be for QM to be necessary?

  • dRic2
  • · Replies 6 ·
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6

Undergrad Why is the QCD Lagrangian often abbreviated?

  • Kara386
  • · Replies 1 ·
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1

Undergrad Is Dirac's Equation Sufficient for Modeling a System of Electrons Without QFT?

  • LarryS
  • · Replies 6 ·
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6

Undergrad How to create the operator of unknown beamsplitter

  • Pattarasak
  • · Replies 2 ·
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2

High School Measuring entangled particles along several angles

  • Xilor
  • · Replies 27 ·
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27

Graduate What is Leakage in terms of quantum computing?

  • David Long
  • · Replies 2 ·
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2

Graduate What's the idea behind propagators

  • Tomishiyo
  • · Replies 5 ·
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5

Graduate States in usual QM/QFT and in the algebraic approach

  • leo.
  • · Replies 5 ·
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5

Undergrad Delayed Choice with both slits closed, What happens?

  • Rohan de Silva
  • · Replies 10 ·
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10

Undergrad Spin eigenstates for x and y axes: why these specific equations?

  • doggydan42
  • · Replies 12 ·
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12

Undergrad Thought experiment: Photons in a box

  • kent davidge
  • · Replies 4 ·
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4

Undergrad Kim et al DCQE optical details

  • Derek P
  • · Replies 4 ·
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4

Undergrad Does the concept of an "object" belong in Quantum Mechanics?

  • Robert Shaw
  • · Replies 8 ·
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8

Undergrad Do Different Observers See Different Entangled States in Quantum Mechanics?

  • Robert Shaw
  • · Replies 5 ·
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5

Graduate What's the energy-spread of the quantum Universe state?

  • Robert Shaw
  • · Replies 65 ·
3
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65

Undergrad Generalized coordinates basic question

  • nomadreid
  • · Replies 5 ·
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5

Undergrad What does "state" mean in quantum mechanics?

  • Robert Shaw
  • · Replies 18 ·
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18

Undergrad Why is the Uncertainty principle inherent to particles?

  • Phys12
  • · Replies 11 ·
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11

High School How does the Doppler shift explain changes in photon energy without interaction?

  • itoero
  • · Replies 16 ·
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16

Undergrad Do we need a reference frame in Quantum Hilbert space?

  • Robert Shaw
  • · Replies 59 ·
2
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59

Undergrad Matrix dimensions of parity operator in Dirac field theory

  • Silviu
  • · Replies 1 ·
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1

Graduate Hermitian conjugate of the derivative of a wave function

  • Gene Naden
  • · Replies 12 ·
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12

Undergrad Hamiltonian in Schrödinger: necessarily total energy?

  • nomadreid
  • · Replies 2 ·
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2

Undergrad What is the significance of commuting operators and CSCO in quantum mechanics?

  • fog37
  • · Replies 11 ·
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11

Undergrad Two questions about "The Physics of Virtual Particles"

  • fox26
  • · Replies 9 ·
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9

Undergrad Can the Schrodinger equation satisfy Laplace's equation?

  • bb1414
  • · Replies 3 ·
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3

High School Cooper pairs and Superconductors

  • Ben Brain
  • · Replies 3 ·
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3

Undergrad Is Superdeterminism a Plausible Explanation for Quantum Mechanics?

  • facenian
  • · Replies 87 ·
3
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Undergrad Why the second quantization Hamiltonian works?

  • MichPod
  • · Replies 1 ·
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1

Undergrad How Does Spin Hall Effect Couple Charge and Spin Current?

  • semc
  • · Replies 1 ·
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1

High School How to increase wave amplitudes

  • drl
  • · Replies 3 ·
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3

High School What is the result of putting a detector on both slits in the 2 slit experiment?

  • drl
  • · Replies 26 ·
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26

High School Interference pattern intensity

  • Sheldon11
  • · Replies 2 ·
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2

Undergrad Explanation of optical phenomena in light of Feynman's Theory

  • Wrichik Basu
  • · Replies 2 ·
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2

Undergrad Can the Time Independent Schroedinger Equation Be Used to Find Unbound States?

  • fog37
  • · Replies 41 ·
2
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41

High School Why can't we find exact position if we know velocity and time change?

  • Kiley
  • · Replies 11 ·
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11

Graduate What was so extraordinary about Landau damping?

  • TheCanadian
  • · Replies 3 ·
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3

Undergrad Are fundamental particles like electrons and protons truly matter waves?

  • Jianphys17
  • · Replies 5 ·
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5

Undergrad Non-Unitary Dynamics: Is it Allowed?

  • dumpling
  • · Replies 2 ·
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2

Undergrad Projection Postulate vs Quantum Randomness

  • LarryS
  • · Replies 2 ·
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2

Undergrad Bremmstrahlung in neutral atom collisions

  • Getterdog
  • · Replies 2 ·
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2

Undergrad Why use complex numbers in quantum wave functions

  • Zaya Bell
  • · Replies 4 ·
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4

Undergrad How Does Light Emission Affect the Wavefunction of an Atom?

  • dumpling
  • · Replies 3 ·
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3

Undergrad Do the SU(n) generators represent any observables?

  • tomdodd4598
  • · Replies 2 ·
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2

Graduate What are some recommended books on non-standard quantum mechanical models?

  • SemM
  • · Replies 9 ·
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9

Undergrad Disctrete vs continuous spectrum

  • Getterdog
  • · Replies 18 ·
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18

High School Understanding the Conversion of Energy Forms in Particle Interactions

  • TheCanadian
  • · Replies 9 ·
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9

Undergrad Do neutral atom collisions affect the continuous nature of black body radiation?

  • Getterdog
  • · Replies 4 ·
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4

High School Why do material particles interact?

  • Vectronix
  • · Replies 4 ·
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4

Graduate Can Quantum Mechanics be Studied in Banach Spaces or Other Non-Hilbert Spaces?

  • SemM
  • · Replies 17 ·
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17

High School How can light be reflected if electrons only absorb or scatter it?

  • _PJ_
  • · Replies 3 ·
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3

Undergrad Why does observation destroy electron interference differently at different frequencies?

  • AhmedHesham
  • · Replies 10 ·
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10

Graduate Time independence of a Noether charge in QFT?

  • JunhoPhysics
  • · Replies 2 ·
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2

Graduate Identical and indistinguishable particles

  • Stephen Tashi
  • · Replies 16 ·
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16

Undergrad EM Radiation of "Permanent" Molecular Electric Dipoles

  • particlezoo
  • · Replies 1 ·
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1

Undergrad Higgs field and energy dependence?

  • asimov42
  • · Replies 16 ·
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16

High School Do unitary operators exist that don't correspond to symmetries?

  • hgandh
  • · Replies 4 ·
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4

Undergrad Show that the integral of the Dirac delta function is equal to 1

  • Doitright
  • · Replies 6 ·
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6

Graduate Mathematical Quantum Field Theory - Renormalization - Comments

  • Urs Schreiber
  • · Replies 9 ·
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9

High School Why do photons stimulate emission in atoms?

  • Somali_Physicist
  • · Replies 20 ·
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20

Undergrad Srednicki QFT Chapter 4 time-evolved operator

  • TeethWhitener
  • · Replies 4 ·
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4

Undergrad Do Polarized Atoms Imply Shifted Electron Orbitals?

  • Getterdog
  • · Replies 2 ·
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2

Undergrad How to experimentally measure a quantum gate

  • confused_man
  • · Replies 1 ·
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1

Graduate What form of the Schrodinger equation do you use for intensity?

  • bluejay27
  • · Replies 1 ·
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1

High School Delayed Choice Quantum Eraser Experiment Results

  • Suleyman EROGLU
  • · Replies 4 ·
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4

Undergrad Noble Gases vs. Halogens: Which Has a Greater Atomic Radius?

  • rpthomps
  • · Replies 1 ·
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1

Undergrad Ground state energy of harmonic oscillator with momentum-dependent potential term

  • Apashanka das
  • · Replies 14 ·
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14

Undergrad Representing a Hamiltonian in an operator form

  • nashed
  • · Replies 4 ·
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4

Undergrad Phase, Bloch sphere versus Feynman path

  • nomadreid
  • · Replies 2 ·
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2

Graduate Probability of obtaining general quantum measurement outcome

  • Danny Boy
  • · Replies 2 ·
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2

Undergrad Can a Pure State be Interpreted as a Mixed State for a Single Particle?

  • nomadreid
  • · Replies 13 ·
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13

High School Preserving causality in the EPR experiment

  • kurt101
  • · Replies 27 ·
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27

Undergrad How Do Oscillations and Interference Define Particles in Quantum Field Theory?

  • FilipLand
  • · Replies 12 ·
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12