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 Why does recombining Stern-Gerlach beams restore the original spin state?

  • Jehannum
  • · Replies 13 ·
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13

High School Are electromagnetic wavelength and quantum wavelength the same thing?

  • Jehannum
  • · Replies 5 ·
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5

Graduate Derive the Principle of Least Action from the Path Integral?

  • hyksos
  • · Replies 5 ·
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5

Graduate Can Bohmian Mechanics Effectively Address Relativistic Quantum Field Theories?

  • atyy
  • · Replies 87 ·
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High School Searching for a Lost PhD Thesis on Black Holes

  • BiGyElLoWhAt
  • · Replies 7 ·
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7

Graduate J-aggregation and H-aggregation differences

  • Sciencestd
  • · Replies 1 ·
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1

High School Why don't electrons fall into the nucleus?.

  • francis20520
  • · Replies 6 ·
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6

Undergrad Schiff moment in classical electrostatics

  • BillKet
  • · Replies 28 ·
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28

Undergrad How do you normalize this wave function?

  • R P Stone
  • · Replies 31 ·
2
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High School Quantum Entanglement spin measurement

  • Frank_H
  • · Replies 10 ·
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10

Graduate How Can I Address the Divergence in $\phi$ and $\ket{\overrightarrow{P}}$?

  • Diracobama2181
  • · Replies 1 ·
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High School Why is an electron's changing behaviour upon observation fascinating?

  • EvilSapphire
  • · Replies 3 ·
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3

Undergrad How did Schrödinger find his equation?

  • Tumorsito
  • · Replies 15 ·
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15

Undergrad Can an electron quantum tunnel inside the potential barrier?

  • Leonardo Muzzi
  • · Replies 7 ·
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7

Graduate General Covariance in Quantum Field Theory

  • Newton-reborn
  • · Replies 11 ·
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11

Undergrad Relativistic quantum mechanics

  • redtree
  • · Replies 32 ·
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Undergrad Repulsion before the screen in a double-slit experiment

  • JonAce73
  • · Replies 11 ·
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11

Insights Misconceptions about Virtual Particles - Comments

  • A. Neumaier
  • · Replies 355 ·
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Undergrad Are Energy Eigenstate Coefficients Real-valued?

  • LarryS
  • · Replies 2 ·
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2

Undergrad Probability of neutrino switching: more massive, more probable?

  • nomadreid
  • · Replies 4 ·
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4

Undergrad Closure in the subspace of linear combinations of vectors

  • Phys12
  • · Replies 2 ·
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2

Graduate Number of thermal photons in a real (finite Q) cavity

  • f95toli
  • · Replies 4 ·
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4

Undergrad Exponential of momenta to entangle harmonic oscillators

  • matteo137
  • · Replies 2 ·
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2

Undergrad Proof of Commutative Operators for Simultaneous Measurement

  • VVS2000
  • · Replies 14 ·
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14

Graduate Conservation of angular momentum in positron-electron annihilation

  • Simon Bridge
  • · Replies 3 ·
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3

Graduate Normalization of the radial part of the spherical harmonics

  • Taz
  • · Replies 14 ·
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14

High School Have quantum micro-black holes been created at CERN?

  • atommo
  • · Replies 11 ·
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11

Undergrad Calculate a spin state as a function of the base spin states

  • Luke_Mtt
  • · Replies 2 ·
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2

Graduate Double slit experiment with electrons

  • Butyln
  • · Replies 7 ·
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7

High School Is diamagnetism only present with varying magnetic fields?

  • jaumzaum
  • · Replies 3 ·
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3

Graduate How can quantum mechanics and special relativity both be true if they're incompatible?

  • Helena Wells
  • · Replies 10 ·
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10

Undergrad How to determine Spinor in Feynman diagram

  • Markus Kahn
  • · Replies 6 ·
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6

Undergrad Quantum spaces without classical counterparts?

  • Ssnow
  • · Replies 5 ·
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5

High School How Could Quantum Communications Operate at Light Speed Given Relativity?

  • darthgoon
  • · Replies 19 ·
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19

Undergrad Renormalisation and running of the φ^3 and other coupling constants

  • tomdodd4598
  • · Replies 22 ·
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High School Entanglement and the double slit: does detection of one particle collapse the other?

  • shlosmem
  • · Replies 13 ·
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13

High School Why are electric and magnetic fields orthogonal in EM waves?

  • SJMCGOWAN777
  • · Replies 3 ·
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3

Undergrad Quantizing the Dirac field with canonical commutation relations

  • JD_PM
  • · Replies 4 ·
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4

Undergrad Jonsson’s apparatus for photons rather than electrons

  • Phys12
  • · Replies 3 ·
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3

Undergrad What is the nature of the photons?

  • Haorong Wu
  • · Replies 7 ·
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7

Undergrad Prove that the norm squared of a superposition of two states is +ve

  • Phys12
  • · Replies 19 ·
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19

Undergrad Necessity of Quantum Gravity given Planck scales for nuclear physics

  • Phys12
  • · Replies 6 ·
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6

Undergrad Bell's Theorem - why product of (2)spins can be +1 (Griffith's text)

  • Sparky_
  • · Replies 1 ·
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Graduate Is randomness real or just a description of complex patterns?

  • blazh femur
  • · Replies 16 ·
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16

Undergrad Solve the particle in a box problem using matrix mechanics?

  • mike1000
  • · Replies 41 ·
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Undergrad Representing Quantum Gates in Tensor Product Space

  • phun_physics
  • · Replies 1 ·
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1

Graduate Reference frame of the vacuum -- which forum?

  • danb
  • · Replies 21 ·
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21

Undergrad Spin-orbit interaction and two inconsistent values

  • hokhani
  • · Replies 1 ·
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Undergrad Photon absorption for an atomic electron

  • Dfault
  • · Replies 47 ·
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Graduate Do bosons contradict basic probability laws?

  • Philip Koeck
  • · Replies 108 ·
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Undergrad What would the world be like if the HUP were not a thing?

  • Souma
  • · Replies 6 ·
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6

Undergrad Can an electron in the 1s orbital be indefinitely far from the nucleus?

  • jaumzaum
  • · Replies 43 ·
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High School Has the Double Slit Experiment been Performed in a Near Vacuum?

  • wolfy
  • · Replies 2 ·
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2

Undergrad Experimental confirmation of the Born rule

  • Dadface
  • · Replies 12 ·
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12

Undergrad The "size" of entangled particles

  • Souma
  • · Replies 18 ·
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18

Undergrad Pair production via Quantum Tunneling has negative Kinetic energy?

  • Superposed_Cat
  • · Replies 3 ·
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3

Undergrad Does quantum theory describe light as a wave?

  • HtimsNats
  • · Replies 7 ·
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7

Undergrad What is the meaning of the mass assigned to an individual quark?

  • Dale
  • · Replies 21 ·
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21

Undergrad Wilson-Sommerfeld quantization to solve square-well potential

  • Robin04
  • · Replies 5 ·
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5

Graduate Eigenstates of ##\phi^4## theory

  • HomogenousCow
  • · Replies 2 ·
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2

Graduate Spin dynamics and the Pauli exclusion principle

  • atomiclaser
  • · Replies 1 ·
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1

Undergrad Meaning of the Orbital Angular Momentum of Super Chiral Light

  • bob012345
  • · Replies 6 ·
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6

Undergrad Hyperfine Splitting: Get Help Understanding It

  • privategenius
  • · Replies 2 ·
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2

Undergrad Are phonons created when hitting a table?

  • CGandC
  • · Replies 2 ·
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2

Undergrad Dirac Lagrangian and Covariant derivative

  • PeroK
  • · Replies 14 ·
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14

Graduate Amplitudes for ##\phi^4## theory

  • PeroK
  • · Replies 4 ·
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4

Undergrad Normal order and overlap of states

  • Markus Kahn
  • · Replies 6 ·
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6

Undergrad Can a Hamiltonian with non-spherical potential commute with l^2?

  • Feelingfine
  • · Replies 2 ·
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2
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3

Graduate Functional Determinant of a system of differential operators?

  • Yellotherephysics
  • · Replies 2 ·
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2

High School Quantum Tunneling different individual transmission probabilities

  • wolfy
  • · Replies 2 ·
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2

Undergrad Spin in Real Space: Meaning of Z-Component

  • hokhani
  • · Replies 7 ·
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7

Graduate Converting between field operators and harmonic oscillators

  • SupernerdSven
  • · Replies 2 ·
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2

Undergrad Schrodinger equation on the complex disk

  • Ssnow
  • · Replies 5 ·
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5

Undergrad The wave function in the finite square well

  • Terrycho
  • · Replies 10 ·
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10

Undergrad What is the energy propagator in quantum field theory?

  • PeroK
  • · Replies 4 ·
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4

Undergrad On 1/2 spin - which is the X axis?

  • MichPod
  • · Replies 39 ·
2
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39

Undergrad Confusion about position state kets

  • Oliver321
  • · Replies 7 ·
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7

Graduate 2-electron system under compression

  • hilbert2
  • · Replies 12 ·
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12

Graduate Absorption of an Exciton and Exciton propagation

  • Sciencestd
  • · Replies 1 ·
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1

Graduate How to calculate the interband velocity matrix in a graphene system

  • Sunny Huang
  • · Replies 1 ·
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1

Undergrad Quantum operators and trasformation under rotations

  • forever_physicist
  • · Replies 3 ·
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3

Undergrad Explaining atoms and bonding using entropy

  • micklat
  • · Replies 10 ·
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10

Undergrad Matrix Representations of the Poincare Group

  • cuallito
  • · Replies 4 ·
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4

Graduate Concurrence as a measure of entanglement

  • LagrangeEuler
  • · Replies 1 ·
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1

Undergrad Using general relativity to violate the uncertainty principle

  • Souma
  • · Replies 14 ·
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14

Undergrad Double Slit Interference Question

  • David Charles
  • · Replies 19 ·
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19

Undergrad Double Slit Interference Question II

  • David Charles
  • · Replies 2 ·
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2

Graduate Quantum computers and Annular Josephson junctions

  • LagrangeEuler
  • · Replies 3 ·
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3

Undergrad Does quantum behavior differ between past and present observation?

  • jellellogram
  • · Replies 2 ·
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2

Undergrad Double slit-experiment confusion

  • user30
  • · Replies 4 ·
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4

High School Can entangled electrons in helium be observed and measured in practice?

  • Andrew Wright
  • · Replies 10 ·
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10

High School Can a photon with wavelength longer than the box be decomposed into eigenmodes?

  • ilper
  • · Replies 15 ·
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15

Undergrad Why isn't the Goldstone boson on the Standard Model map?

  • bland
  • · Replies 3 ·
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3

Undergrad Really? Schrödinger's cat again?

  • DaveE
  • · Replies 6 ·
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6

Undergrad Why is the speed of photons different?

  • GREENMONKEY
  • · Replies 4 ·
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4

Graduate Normalizing quantum price returns from anharmonic oscillator eigenvalues

  • yosmod04
  • · Replies 9 ·
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9

Undergrad Is Quantum Mechanics Infinitely More Complex than Classical Mechanics?

  • bob012345
  • · Replies 55 ·
2
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55

Undergrad Lorentz violation, multiple preferred frames, vacuum energy

  • asimov42
  • · Replies 16 ·
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16

Undergrad Physicists entangle 15 trillion hot atoms

  • Tom.G
  • · Replies 0 ·
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0