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Quantum Interpretations and Foundations

Seeking clarity on the physical definition of an observer
1.3K threads
Seeking clarity on the physical definition of an observer
Undergrad Another Interferometry question please
  • desertshaman
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Undergrad Can Topological Protection Extend the Lifetime of a Qubit?
  • Emrissa
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Undergrad Relation between operators and their variables' signs
  • hokhani
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High School Can a filter based on the photoelectric effect reduce the noise floor?
  • danielhaish
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Undergrad Incomprehension of a simple interferometer?
  • desertshaman
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Undergrad Double-dark Slit Interference Pattern?
  • Quarker
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Undergrad What kind of integration is Berezin integration?
  • pines-demon
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High School The Story of Least Action and the Double Slit
  • jedishrfu
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Undergrad Please help me understand the double slit experiment and conclusion
  • jackjack2025
  • · Replies 65 ·
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Undergrad Understanding the proof of Goldstone theorem
  • pines-demon
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Undergrad Quick question regarding creation/annihilation operators
  • MaestroBach
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High School Are the electron and neutrino that are emitted in a beta decay entangled?
  • rjhoward12447
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Undergrad Homemade double slit experiment
  • desertshaman
  • · Replies 11 ·
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11
Undergrad Have You Heard of the SEW Experiment? Thoughts?
  • ChadGPT
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Graduate Does x affect the value of [a^2,(a^†)^2×e^2ikx]
  • Sciencemaster
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Undergrad Units analysis for this phase shift problem using a differential equation
  • jhonconnor
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Undergrad Clarifying the Superposition Principle
  • MatinSAR
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Undergrad The physical components in the electron double slit experiment
  • jacobbry
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7
High School How does light have energy to follow infinite paths?
  • oknow
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High School The arrow of time (again)
  • TheHutch
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High School Yet another double slit thought experiment...
  • PhysicsIsReallyFun
  • · Replies 20 ·
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High School Probability function for the position of a static electron under no potential
  • Arend
  • · Replies 9 ·
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High School Photoelectric phenomenum can only be proved as a particle effect?
  • Arend
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Undergrad Femto-photography Michelson Morley Interferometer thought experiment
  • Spinnor
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High School Would Laplace's Demon work?
  • sayetsu
  • · Replies 12 ·
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Undergrad Quantum fields and "mediator" particles
  • Rick16
  • · Replies 7 ·
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High School Why is gravity a weak force at the atomic scale?
  • Arend
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Undergrad Entropic Tension Cosmology (ETC) 1.0
  • Charles1
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6
Undergrad What Are the Key Questions and Challenges in Understanding Quantum Gravity?
  • SephQ
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Graduate Historical clarification of the Planck formula of blackbody radiation
  • matteoargos
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High School Quantum Field Theory As Simple As Possible
  • bhobba
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Undergrad Far off resonant Rabi oscillations in a 2 level system
  • Malamala
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Undergrad Different expressions about time reversal and confusion
  • hokhani
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Undergrad Is the result of an operator acting on a ket vector always a ket？
  • gaiussheh
  • · Replies 16 ·
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Undergrad Double Slit Experiment: Measurement versus Observation
  • Praxiteles
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3
Undergrad Deriving the time-dependent wave equation from Energy eigenfunctions
  • Dirac_Clarity_GOAT
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Undergrad How Much Pressure To Cause Matter To Degenerate?
  • Hornbein
  • · Replies 11 ·
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11
Undergrad Particle in Infinite Square Well
  • AgingStudent49
  • · Replies 6 ·
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Undergrad Justification of Superposition of Waves with Different Speeds
  • greypilgrim
  • · Replies 19 ·
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Undergrad Particle in a potential well
  • Malvina
  • · Replies 11 ·
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11
Undergrad Feynman's summing arrows for photon amplitudes applied to LIGO?
  • Spinnor
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Undergrad Laws of thermodynamics and their application to quantum physics
  • Priscilaifrj
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Undergrad Explanation of the Bohr postulates' existence
  • Timothy S.
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Undergrad Can two photons combine to give a local field with spin 2?
  • south
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Undergrad Physical Meaning of Atomic Oscillations
  • Sciencemaster
  • · Replies 11 ·
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Graduate Pauli spin matrices
  • Eliena
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Undergrad The Pauli-Lubanski vector and angular momentum
  • redtree
  • · Replies 19 ·
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Undergrad Chunks of action smaller than Planck's constant
  • gerald V
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Graduate Collapse of the electron wave function due to inelastic interactions
  • Philip Koeck
  • · Replies 8 ·
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Undergrad Question regarding quantum mechanics from relativity perspective
  • Cjorgensen
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Undergrad Normalisation Constant In Wavefunction
  • laser1
  • · Replies 8 ·
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Graduate Has Hilbert transform ever been used in Quantum Theory?
  • mad mathematician
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Undergrad What do the wave functions of real particles look like?
  • AlbinoAlpacca
  • · Replies 13 ·
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Undergrad Uniqueness of quantum numbers
  • ecurbian
  • · Replies 3 ·
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Undergrad Time dependent Schrödinger equation - Separable Solutions
  • laser1
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Undergrad Is Newton the founder of quantum gravitation?
  • south
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5
Undergrad Lower energy levels with Dirac/Pauli theory than Schroedinger theory?
  • Juli
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Undergrad Amount of electrons in nuclei
  • snorkack
  • · Replies 10 ·
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Undergrad System of bosons
  • ananonanunes
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2
Undergrad Exchange symmetry of two particles on a sphere
  • Siupa
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Undergrad The probability density of a wave function due to length contraction
  • Wo Wala Moiz
  • · Replies 20 ·
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Undergrad 3 photon transfer probability
  • Malamala
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Undergrad Motivating the form of a bra vector
  • LightPhoton
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Undergrad How is superposition demonstrated?
  • Halc
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Undergrad Physics Today article collection
  • Frabjous
  • · Replies 1 ·
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High School Quantum wavelength of gravity
  • south
  • · Replies 11 ·
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11
Graduate Questions about changing frame in QM and rotating wave approximation
  • Malamala
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Graduate Classical interpretation of the Thomson experiment compared to the modern quantum perspective
  • PaulinsteinAmarx
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Undergrad Quantum field in curved space-time
  • Gary Venter
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High School Interference pattern inferencing
  • roineust
  • · Replies 8 ·
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Undergrad Macroscopic object wave function
  • fhenryco
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Undergrad Heisenberg Uncertainty Principle and macroscopic objects
  • wnvl2
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Undergrad How does the electron keep its properties?
  • JC_Silver
  • · Replies 5 ·
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Undergrad Understanding Randomness in Brownian Matter
  • EntropicThinker
  • · Replies 4 ·
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Graduate CHSH Bell inequality derivation
  • d_bar_x
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Graduate Born's probability in decoherence
  • Sr1
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High School Sketching Psi as a function of x
  • tsumugori
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15
Undergrad Famous 'Aspect Experiment' -- Which Type of Polarizers Were Used?
  • d_bar_x
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Undergrad Influence of electron's kinetic energy disspation during photoelectric emission
  • Timothy S.
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Undergrad 2-Slit: How do we know photon guns only produce single photons?
  • julianb
  • · Replies 33 ·
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Graduate Order of Galilean Boost / Translation on a wave-function (or fields)
  • binbagsss
  • · Replies 9 ·
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9
Graduate Vector Spaces Associated with Quark Modes in k-Space
  • Hamracek21
  • · Replies 0 ·
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0
Undergrad Diffraction of point source/s and duality
  • jk22
  • · Replies 2 ·
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2
High School Heisenberg uncertainty principle -- Questions about a practical experiment
  • L Drago
  • · Replies 34 ·
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Undergrad Delayed quantum eraser: turning off sensor to bring back interference
  • Herbascious J
  • · Replies 24 ·
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24
High School A homebrew quantum computer simulator
  • Bob Walance
  • · Replies 6 ·
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6
Graduate Entropy increase in proton/proton collision?
  • Twodogs
  • · Replies 4 ·
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Graduate Two-electron Lagrangian in QED
  • Fefetltl
  • · Replies 4 ·
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4
High School Is space-time curvature a curvature of the Higgs field?
  • C18
  • · Replies 2 ·
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Undergrad Relativity Considerations for Measurements on a Free Particle
  • member 743765
  • · Replies 1 ·
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Undergrad How to derive momentum operator in position basis via its definition?
  • LightPhoton
  • · Replies 6 ·
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6
Undergrad Why is the coupling factor constant in QFT?
  • Haorong Wu
  • · Replies 1 ·
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Undergrad How to find common eigenbases of momentum and energy in infinite well?
  • LightPhoton
  • · Replies 9 ·
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Undergrad Has superdeterminism been proven recently?
  • vertig0
  • · Replies 3 ·
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3
High School What particle represents the mass-energy conversion in a proton?
  • veemon293
  • · Replies 4 ·
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4
High School How would a hypothetical graviton escape a black hole?
  • DaveC426913
  • · Replies 10 ·
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10
Graduate Any relation between Quantum Chaos and Quantum Field Theory?
  • mad mathematician
  • · Replies 10 ·
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Graduate Spectral Decomposition of Constant Functions Utilizing Fourier Harmonics
  • Bret Danfoss
  • · Replies 7 ·
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7
Undergrad Lagrangian Mechanics, Continuous Particle Paths and QFT
  • Islam Hassan
  • · Replies 6 ·
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Undergrad Why do ##t## and ##-i\hbar\partial_t## not satisfy the definition of a linear map/operator in Hilbert space?
  • Dr_Nate
  • · Replies 4 ·
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