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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.

Quantum Interpretations and Foundations

Graduate Understanding Barandes' microscopic theory of causality
Undergrad Parametric down-conversion and double-slits
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Undergrad Negative Energy -- Are QI/QEI's Real?
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Undergrad Lithium Atom Ground State Radial Wavefunction
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Undergrad Is Chemistry the same everywhere?
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High School How much math is required to do QM?
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Graduate Understanding the Math behind meson decay computations
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Graduate Why do different regularization schemes give different answers?
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High School How can the annihilation operator for photons be realized experimentally?
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Undergrad Is it possible to explain Quantum tunneling with the HUP?
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Graduate Why Is the Path Integral W[J] a Vacuum-to-Vacuum Amplitude?
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Undergrad Unveiling the Math Behind Potential Well Boundaries
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Undergrad Number of qubits required for Shor's algorithm to factor a number < 2^n
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Undergrad Thermal photons emission inside a material
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Undergrad Vertex function, quantum action
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Undergrad Finding matrices of perturbation using creation/annihilation operators
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High School Calculating Photon Polarization States with PBS & Wave Plates
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Graduate Bremsstrahlung single photon or spectrum
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Undergrad Accuracy of the Density of States
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Graduate Coherent states: Orthonormal set? Overcomplete basis?
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High School Ionization energy and energy levels
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Undergrad Group Theory Appearing in Griffith's Elementary Particles (2nd Ed.)
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Graduate How ‘spooky’ is quantum physics? The answer could be incalculable
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Undergrad Why perturbation theory uses power series?
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Undergrad Splitting of a one-particle wave function
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Graduate Why is the quantum Fisher information useful in quantum metrology?
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High School What's the exact point about time travel?
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Undergrad (Baby QM) Analytic Solution to the Infinite Square Well Problem
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Graduate Decoupled spin vectors A and B
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Graduate How are basis vector relationships defined in incompatible propositions?
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Undergrad Nomenclature : global or constant phase
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Undergrad Fermi's golden rule derivation a bit hazy
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High School Quantum computing -- How is the relevant solution selected?
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Graduate Does Adding or Removing an Electron Change a Helium-3 Atom to a Boson?
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Graduate Product of Representations of Lorentz Group
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Graduate Superluminal origin of Quantum Mechanics
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Undergrad Thought experiment on photon entanglement
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Undergrad Vacuum amplitudes in \phi^4 theory
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Undergrad Clarification on a statement about spin 1/2 z component related to x and y
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Undergrad Commutator with gradient operator (nabla)
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Graduate Algebraic form of Klein Gordon ##\phi^4## vacuum and ladder operators
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Undergrad Creation/annihilation operators question
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Undergrad Explaining Time Crystals: Matter, Mass & 4D
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Undergrad Quantum Mechanics Particle in a Box
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Graduate Looking Under the Hood of Feynman Diagrams
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Graduate Potential step at a Barrier in Quantum mechanics
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High School Are all quantum fields coherent?
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Graduate Can Bloch Waves Reveal Periodic Potentials in Quantum Mechanics?
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Undergrad Virtual particle content of the vacuum state....
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Undergrad Is the Kronecker Delta Calculation in Peskin and Schroeder's Solution Correct?
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Undergrad Quantum Measurement under Heisenberg Picture?
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Graduate Ground state energy of cube-like potential wells
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Undergrad 'Off-shell' particle in an external field....
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Graduate Validity of Scalar Field Lagrangian with Linear and Quadratic Terms
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Graduate QFT topics for entanglement entropy
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Undergrad Frank Wilczek on Virtual Particles and Summing diagrams....
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Undergrad The Dirac Equation: Understanding Spinors and Approximations
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Undergrad Perturbation lines for the 1s hydrogen electron
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Undergrad Time measurement in a double slit experiment with single photons
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High School From radio signal to corresponding photons
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Graduate How to build a qubit (theoretically)?
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Undergrad What is the Fourier conjugate of spin?
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Graduate Understanding Superposition Physically and Mathematically
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Undergrad Atoms in a harmonic oscillator and number states
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Graduate Quantum entanglement and quantum foundation
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High School Questions about measurement devices in the double slit experiment
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Undergrad 2nd Order Perturbation Theory Energy Correction
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Graduate Commutation between spin-operator and creation operator(QFT)
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Graduate Quantum Information research frontier
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Undergrad Definition of a Degenerate Subspace (QM)
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High School How does the double slit experimental apparatus actually work?
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Graduate Double slit experiment with magnetic traps
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High School Adjoint Operation in Shankar's "Principles of Quantum Mechanics
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Undergrad The density of states independent of Boundary Conditions
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Undergrad Valley degeneracy in tunneling current
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Graduate Effect of Spin on Vacuum Energy
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Undergrad Is there some agreement on properties of a theory of quantum gravity?
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Undergrad What is an Eigenstate? Simple Explanation
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Undergrad Confused by Notation? Perturbation Theory Explained
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Undergrad Conjugate variables: two descriptions (Link?)
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High School Quantum Computing for Beginners: Understanding Double Hadamard Gates
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Undergrad Relationship between a Lie group such as So(3) and its Lie algebra
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High School What is the significance of 'i' in quantum computation notation?
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High School Is sunlight through gaps in leaves during an eclipse decohered?
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Undergrad When does the exchange operator commute with the Hamiltonian
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High School We can't unite QM with GR because of what the Qfield is capable of
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Undergrad Heisenberg Uncertainty: simple explanation required please
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High School How do orthogonal waves interfere?
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Undergrad Understanding algorithmic information theory's reality
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Graduate Commutation relations between HO operators | QFT; free scalar field
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Graduate Stone's theorem on one-parameter unitary groups and new observables?
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Undergrad Rotation problem in Quantum Mechanics
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Undergrad Von Neumann entropy for "similar" pvm observables
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Undergrad Is the potential energy always negative in the ground state of a hydrogen atom?
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High School Emission from a coated cathode and tunneling
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Graduate What Conditions Allow the Derivative Trick for Evaluating Fermionic Commutators?
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Graduate How effective can QM be to understand the mind and/or consciousness?
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Undergrad Question on the SG (Stern-Gerlach) Spin experiment
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Graduate Unraveling the Mystery of Coherent States for Graduate Students
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High School Can we measure any two of the energy, momentum or mass simultaneously?
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Graduate Understanding Hermiticity of Actions in QFT for Checking and Confirming
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