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 Qubit mixed state density matrix coordinates on a Bloch ball

  • maxverywell
  • · Replies 2 ·
Replies
2

High School Quantum Mechanics vs. Pilot-Wave thought experiment

  • cala
  • · Replies 20 ·
Replies
20

Undergrad Can someone please explain Scott Aaronson lecture #9?

  • mike1000
  • · Replies 29 ·
Replies
29

Undergrad Are two entangled photons described by the same wavefunction?

  • Nickyv2423
  • · Replies 6 ·
Replies
6

High School Interference pattern after a particle is detected?

  • Nickyv2423
  • · Replies 11 ·
Replies
11

Undergrad How does spin relate to the symmetry of a particle?

  • kregg87
  • · Replies 3 ·
Replies
3

Undergrad Heisenberg's Uncertainty Principle common misconceptions

  • Jimmy87
  • · Replies 52 ·
2
Replies
52

Undergrad No r dependence in L operator?

  • DoobleD
  • · Replies 32 ·
2
Replies
32

High School Clarification Requested: Particles as higher dimensional objects

  • zeroace
  • · Replies 1 ·
Replies
1

Undergrad How Fermat's principle interprets diffraction and interference

  • zhouhao
  • · Replies 1 ·
Replies
1

High School Interference pattern, one particle at a time

  • MindWalk
  • · Replies 25 ·
Replies
25

Undergrad Commuting observables vs. exchanging measurements

  • greypilgrim
  • · Replies 5 ·
Replies
5

High School Electron in the double-slit experiment

  • Jens Lundell
  • · Replies 33 ·
2
Replies
33

High School What is the fundamental principle behind the operation of a laser?

  • Karolus
  • · Replies 9 ·
Replies
9

Undergrad Cognitive Dissonance and Quantum Mechanics?

  • mike1000
  • · Replies 18 ·
Replies
18

Undergrad Why does topology matter in determining fermions and bosons?

  • Jezza
  • · Replies 4 ·
Replies
4

Undergrad How is weak isospin/hypercharge calculated?

  • Harry235435
  • · Replies 1 ·
Replies
1

Graduate Are there different "types" of renormalization

  • ftr
  • · Replies 17 ·
Replies
17

High School Here is a good video that explains non-locality simply

  • mike1000
  • · Replies 18 ·
Replies
18

Graduate Feynman rule for closed fermion loop in QED

  • spaghetti3451
  • · Replies 4 ·
Replies
4

Graduate Classical universe and experimental choices

  • A. Neumaier
  • · Replies 17 ·
Replies
17

Undergrad Does Quantum Mechanics Deny Objective Reality Before Measurement?

  • RTT
  • · Replies 5 ·
Replies
5

High School Does right/left spin reverse in tunneling particles?

  • fredt17
  • · Replies 17 ·
Replies
17

High School How does Hawking radiation work?

  • caspeerrr
  • · Replies 2 ·
Replies
2

Graduate Can three particles be entangled?

  • caspeerrr
  • · Replies 2 ·
Replies
2

Undergrad What Are the Key Experiments and Interpretations of Quantum Physics?

  • skanskan
  • · Replies 2 ·
Replies
2

Undergrad Expectation value with imaginary component?

  • Kenneth Adam Miller
  • · Replies 25 ·
Replies
25

Undergrad What mediates the exchange force?

  • Ben Wilson
  • · Replies 23 ·
Replies
23

Graduate How Do Gamma Matrix Identities Relate to the Charge Conjugation Operator?

  • Bala Tala
  • · Replies 2 ·
Replies
2

Undergrad Why all the rejection of superdeterminism?

  • greypilgrim
  • · Replies 112 ·
4
Replies
112

Undergrad Symmetrized Lagrangian (second quantization)

  • Neutrinos02
  • · Replies 3 ·
Replies
3

Graduate Flow of charge on fermion propagator

  • spaghetti3451
  • · Replies 1 ·
Replies
1

High School What are we made of? (IB project)

  • Nikola Milekic
  • · Replies 8 ·
Replies
8

Insights Examples of Prequantum Field Theories III: Chern-Simons-type Theories

  • Urs Schreiber
  • · Replies 1 ·
Replies
1

Undergrad Does ΔPΔX = ΔEΔT? Solving the Uncertainty Principle

  • mike1000
  • · Replies 44 ·
2
Replies
44

Undergrad Boltzmann with degenerate levels

  • jostpuur
  • · Replies 34 ·
2
Replies
34

Undergrad Energy Level Change in Adiabatic Reversible Process

  • Sorade
  • · Replies 1 ·
Replies
1

High School Understanding Beta Decay: The Role of Quarks, Leptons, and Bosons

  • Comeback City
  • · Replies 8 ·
Replies
8

Undergrad Photoelectric absorption versus Compton scattering

  • cdot1989
  • · Replies 5 ·
Replies
5

Undergrad Difference between "realistic" and "predetermined"

  • greypilgrim
  • · Replies 2 ·
Replies
2

Graduate What Drives the Naming and Structure of One-Particle Irreducible Diagrams?

  • spaghetti3451
  • · Replies 1 ·
Replies
1

Undergrad Double slit experiment in 3 dimensions?

  • mike1000
  • · Replies 77 ·
3
Replies
77

Undergrad Bell's inequality experimental data

  • Nivloc
  • · Replies 2 ·
Replies
2

Undergrad Calculation of negative energy density in a Casimir cavity

  • OrigamiNinja
  • · Replies 21 ·
Replies
21

Undergrad Bell scenarios with communication

  • DrClaude
  • · Replies 1 ·
Replies
1

Undergrad Internal rotation kinetic energy operator

  • Konte
  • · Replies 2 ·
Replies
2

Insights The Physics of Virtual Particles - Comments

  • A. Neumaier
  • · Replies 32 ·
2
Replies
32

Graduate Weinberg: detecting changes to QM using atomic clocks

  • Auto-Didact
  • · Replies 2 ·
Replies
2

High School Electron moving to lower energy state

  • Simon Peach
  • · Replies 8 ·
Replies
8

Graduate Quantum Interest Conjecture and negative energy-density

  • exvitermini
  • · Replies 3 ·
Replies
3

Undergrad A question about assumptions made in derivation of LSZ formula

  • Frank Castle
  • · Replies 10 ·
Replies
10

Graduate Could someone explain Luders Rule?

  • TimH
  • · Replies 3 ·
Replies
3

High School Summation vs Integral for Wavefunction Superposition

  • Isaac0427
  • · Replies 24 ·
Replies
24

Graduate A surprise result using Helmann-type potential

  • ftr
  • · Replies 3 ·
Replies
3

Undergrad Understanding POVM: A Simple Explanation

  • Trixie Mattel
  • · Replies 5 ·
Replies
5

Undergrad Do photons that carry orbital angular momentum have mass?

  • calinvass
  • · Replies 5 ·
Replies
5

Undergrad The "complete state" of an electron

  • ExplosivePete
  • · Replies 2 ·
Replies
2

Undergrad Please help me understand quantum tunneling conceptually?

  • nashsth
  • · Replies 13 ·
Replies
13

Graduate Busting the myth of the observer: the double slit experiment

  • steviereal
  • · Replies 72 ·
3
Replies
72

Undergrad What is the Waveform of Virtual Photons?

  • Jeff Root
  • · Replies 4 ·
Replies
4

High School Is the Universe Just a Computer Simulation?

  • TJung
  • · Replies 1 ·
Replies
1

Graduate Is Each Pair in a Tripartite Cubic System in a Bell State?

  • salley
  • · Replies 2 ·
Replies
2

Undergrad Occam's razor and probability in QM

  • simeonz
  • · Replies 29 ·
Replies
29

Graduate Why is the Matter wave analogous to photon and derived from it?

  • SunRay-dvsh
  • · Replies 13 ·
Replies
13

High School Need Listing of Photon and Particle Quantum States

  • Adam Computes
  • · Replies 5 ·
Replies
5

Undergrad Interpreting These '2 Particles in a Box' Plots

  • tomdodd4598
  • · Replies 7 ·
Replies
7

Undergrad Is nuclear fission a quantum fluctuation

  • rootone
  • · Replies 19 ·
Replies
19

Graduate Path integral formula for a state with non-trivial time dependency

  • ShayanJ
  • · Replies 14 ·
Replies
14

High School Does Material Type Affect Double Slit Interference Patterns?

  • hsdrop
  • · Replies 15 ·
Replies
15

High School Bypassing Pauli Exclusion principle.

  • MathematicalPhysicist
  • · Replies 3 ·
Replies
3

Undergrad Are fixup operations required for entanglement in photon splitting?

  • edguy99
  • · Replies 16 ·
Replies
16

Undergrad Doppler Shift and Light Quanta: Questions on the Nature of Light and Observation

  • Andy_K
  • · Replies 3 ·
Replies
3

Undergrad Particle in the box eigenfunctions

  • fog37
  • · Replies 60 ·
3
Replies
60

Undergrad What Are Quantum Operators and the Role of Hermitian Matrices in Degeneracy?

  • Karolus
  • · Replies 10 ·
Replies
10

Undergrad Harmonic Oscillator equivalence

  • Adolfo Scheidt
  • · Replies 8 ·
Replies
8

Graduate Expert on Wick's Theorem needed

  • mupsi
  • · Replies 14 ·
Replies
14

High School Why did famous people think consciousness causes collapse?

  • low inhibition
  • · Replies 43 ·
2
Replies
43
Replies
1

Undergrad "Iterativity" of quantum potential?

  • itssilva
  • · Replies 14 ·
Replies
14

High School Understanding Environment-Induced Superselection in Quantum Systems

  • fanieh
  • · Replies 3 ·
Replies
3

Undergrad A few questions about Feynman's QED Lecture

  • JohnnyGui
  • · Replies 14 ·
Replies
14

Undergrad The absolute value of the frequency in quantum mechanics

  • mccoy1
  • · Replies 2 ·
Replies
2

High School Double slit experiment -- consciousness and information

  • Viopia
  • · Replies 52 ·
2
Replies
52

Undergrad Rotational excitation of quantum particle

  • quantumSpaghetti
  • · Replies 1 ·
Replies
1

Graduate Is my solution of time-dependent Schrodinger equation right?

  • extranjero
  • · Replies 10 ·
Replies
10

High School Understanding Quantum Mechanics: The Puzzle of Cutting a Pencil in MWI

  • oquen
  • · Replies 18 ·
Replies
18

Undergrad Amplitudes, Probabilities and EPR

  • stevendaryl
  • · Replies 81 ·
3
Replies
81

Undergrad How Does Bell's Inequality Reveal Quantum Nonlocality?

  • exponent137
  • · Replies 10 ·
Replies
10

Undergrad On the Heisenberg uncertainty relation

  • A. Neumaier
  • · Replies 49 ·
2
Replies
49

Undergrad How Do You Calculate the Average Orbital Kinetic Energy for Silicon?

  • Ado
  • · Replies 5 ·
Replies
5

Undergrad How Does Semiclassical State Counting Relate to Quantum Energy Eigenstates?

  • jostpuur
  • · Replies 2 ·
Replies
2

Undergrad Gravitational Effect on Electron Eigenstates

  • Jim Lundquist
  • · Replies 5 ·
Replies
5

Undergrad Odd/even symmetric/antisymmetric

  • dyn
  • · Replies 1 ·
Replies
1

High School Practical applications of quantum mechanics

  • Jazzy Smaff
  • · Replies 3 ·
Replies
3

Undergrad Expectation of an operator (observable) how to calculate it

  • fog37
  • · Replies 11 ·
Replies
11

High School Neutron, White Dwarfs and Degeneracy Pressure

  • Jimmy87
  • · Replies 1 ·
Replies
1

Undergrad From Pauli spinors to Dirac spinors

  • Milsomonk
  • · Replies 8 ·
Replies
8

Undergrad Quantum Computing: Learn to Start From Scratch

  • Dahvrok
  • · Replies 1 ·
Replies
1

Graduate Do all photons really follow all available paths?

  • physics pfan
  • · Replies 4 ·
Replies
4

High School How close are we to uniting gravity and QM

  • ChrisisC
  • · Replies 2 ·
Replies
2