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Showing 271–300 of 365 reference entries
The strong coupling α_s depends on renormalization scale and scheme.
ModelPhysicsPrecision electroweak fits and nuisance parametersA precision Standard Model fit compares predicted electroweak observables with correlated measurements, jointly propagating input-parameter, systematic and missing-order uncertainties.
MethodPhysicsMuon g−2 · Final detailed Fermilab report (2026)The Muon g−2 Collaboration's June 2026 detailed report describes the final positive-muon anomaly measurement at 127 ppb precision, including precession frequency, calibrated magnetic field and beam-dynamics corrections.
Empirical findingPhysicsMuon hadronic vacuum polarization · Competing inputsData-driven dispersion calculations and lattice QCD estimate the same hadronic contribution through different inputs and systematics.
ModelPhysicsHubbard interaction and competing approximationsA single-band Hubbard model combines hopping t_ij with on-site repulsion U n_i↑n_i↓.
ModelPhysicsDynamical mean-field method and localitySingle-site dynamical mean-field theory maps an interacting lattice problem to a self-consistent impurity problem with a frequency-dependent local self-energy.
MethodPhysicsChern number, Hall response and edge indexFor a gapped noninteracting two-dimensional band system, the occupied-band Berry curvature integrates to an integer C=(2π)⁻¹∫_BZTrF_xy d²k.
ModelPhysicsTime-reversal topology and experimental signaturesSpinful time-reversal symmetry with T²=−1 permits a Z₂ band distinction even when total Chern number vanishes.
ModelPhysicsKitaev chain and Majorana boundary modesAn ideal spinless one-dimensional p-wave pairing chain has a gapped topological phase with boundary Majorana modes for nonzero pairing and |μ|<2|t| in the uniform nearest-neighbour model.
ModelPhysicsFloquet topological order · Processor study (2025)Will, Cochran and collaborators reported signatures of non-equilibrium topological order in a periodically driven quantum-processor experiment published 10 September 2025.
Empirical findingPhysicsMajorana versus Andreev interpretationsLiu, Sau and Das Sarma's 2018 nanowire calculations show how trivial Andreev bound states can generate local zero-bias peaks resembling topological Majorana signals.
ModelPhysicsKinetic equations and molecular-chaos closureThe Boltzmann equation evolves a dilute one-particle distribution with streaming, force and collision terms.
ModelPhysicsThermalization, ETH and generalized Gibbs ensemblesETH proposes that suitable local-observable matrix elements in many chaotic energy eigenstates have thermal structure, allowing narrow-energy isolated preparations to approach thermal local expectations.
ModelPhysicsCausal linear response and transport inferenceFor perturbation H′(t)=−f(t)B, the retarded response of A is χ_AB(t)=(i/ħ)θ(t)⟨[A(t),B(0)]⟩ in an equilibrium reference state.
MethodPhysicsLow-energy quantum gravity as an effective theoryExpanding a diffeomorphism-invariant gravitational action in curvature and derivatives organizes low-energy quantum corrections without claiming a complete short-distance theory.
ModelPhysicsQuantum-gravity frameworks and unresolved testsString theory organizes extended-object states and includes a massless spin-two excitation in appropriate constructions; loop approaches quantize geometric variables with spin-network/holonomy methods; asymptotic safety seeks a suitable ultraviolet renormalization-group fixed point.
Open questionPhysicsGravity-induced entanglement · What would it establish?The 2017 Marletto–Vedral proposal links entanglement between two masses to nonclassical mediation under explicit subsystem and locality assumptions.
ModelPhysicsReynolds stresses and turbulence closureFor constant-density incompressible flow, averaging u=U+u′ adds the Reynolds stress R_ij=⟨u′_iu′_j⟩ to the mean momentum equation.
MethodPhysicsDNS, filtered models and convergence evidenceDNS aims to resolve the dynamically relevant viscous scales of a specified flow; LES filters resolved scales and models subfilter stress.
MethodPhysicsNonlinear optical polarization and phase matchingA nonlinear polarization drives new frequency components.
ModelPhysicsKerr envelopes, dispersion and soliton limitsIn a lossless scalar narrowband Kerr envelope convention, i∂_zA=−D∂²_tA+δ|A|²A represents second-order dispersion and self-phase modulation.
ModelPhysicsFDTD stability, boundaries and physical validationYee FDTD staggers electric/magnetic fields in space and time to approximate Maxwell curl evolution.
MethodPhysicsA mixing-layer benchmark and observable dependenceNichols' worked compressible mixing-layer comparison specifies two streams, geometry, initial transients and statistical sampling before comparing RANS, LES and hybrid predictions with measurements downstream.
MethodPhysicsDisplacement, distance and average speedDisplacement compares endpoints; distance measures the travelled path.
ModelPhysicsConstant-acceleration kinematicsClosed formulas require constant acceleration over the interval.
ModelPhysicsInertial reference frames and inertiaNewtonian force balances need an inertial frame or explicit inertial terms.
ModelPhysicsCircular motion and centripetal accelerationA constant speed can still have an acceleration.
ModelPhysicsMass, gravitational weight and apparent weightMass is in kilograms; gravitational weight is a force.
ModelPhysicsNormal forces and tensionContact geometry determines the force direction.
ModelPhysicsFree-body diagrams and system boundariesList forces on the selected body once.
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