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For an independently conserved homogeneous component with constant equation-of-state w, density scales with a as a^-3(1+w).
MethodEarth & cosmosMatter, radiation and vacuum expansion solutionsCombining a conserved component with flat single-component Friedmann expansion yields matter a∝t^(2/3), radiation a∝t^(1/2) and vacuum exponential expansion.
MethodEarth & cosmosJoint cosmological likelihoods and nuisance degeneraciesCosmological parameter inference combines data likelihoods with model priors and nuisance parameters for foregrounds, calibration and selection.
MethodEarth & cosmos2026 preprint: DESI Lyman-alpha geometry and dark-energy inferenceDESI DR2 Lyman-alpha Alcock–Paczyński measurements add redshift-dependent geometry information with blinded validation and contaminant controls.
MethodEarth & cosmosDeclared isotope reaction networks and stiff abundance balanceA reaction network lists its species and reactions, evolves abundances with a stoichiometric matrix and couples nuclear energy release and escaping neutrino losses to stellar energy.
MethodEarth & cosmosCross-section, resonance and screening uncertaintyThermal rates average microscopic cross sections over a specified particle distribution.
MethodEarth & cosmosCore-collapse neutrino transport and closureCore-collapse models couple dense-matter EOS, fluid motion and flavor/energy-dependent neutrino radiation.
MethodEarth & cosmosCompact-star EOS inference across messengersDense-matter inference combines nuclear constraints, pulse-profile models and gravitational-wave likelihoods with an EOS parameterization.
MethodEarth & cosmosGRMHD conservation and declared boundary dataIdeal GRMHD evolves rest-mass and stress-energy conservation with magnetic induction in a specified spacetime.
MethodEarth & cosmosMagnetorotational transport and magnetic-flux dependenceWeak well-coupled magnetic fields can destabilize outwardly decreasing differential rotation and drive angular-momentum transport.
MethodEarth & cosmosKinetic reconnection and particle-population limitsParticle-in-cell reconnection experiments evolve fields and particle distributions rather than assume a thermal fluid closure.
MethodEarth & cosmosPolarized synchrotron and self-absorptionFor isotropic power-law electrons in a uniform field, optically thin synchrotron has a conditional spectral slope and maximum linear polarization.
MethodEarth & cosmosInverse Compton angular kernels and Klein–Nishina regimeInverse Compton energy gain depends on incident angle and the photon energy in the electron rest frame.
MethodEarth & cosmosPhoton-pair threshold, opacity and cascadesTwo photons can produce an electron–positron pair only above an angle-dependent invariant threshold.
MethodEarth & cosmosCollisionless N-body force and resolution testsA particle realization approximates a smooth collisionless distribution; force softening and time integration control numerical encounters and force error.
MethodEarth & cosmosGalaxy gas dynamics and matched-solver comparisonsFinite-volume hydrodynamics updates conserved quantities using fluxes across cell boundaries; moving faces require fluxes in the face frame.
MethodEarth & cosmosBar and spiral orbital resonancesRotating nonaxisymmetric potentials exchange angular momentum at corotation and Lindblad resonances.
MethodEarth & cosmosElement-resolved delayed recycling and gas flowsChemical evolution follows an element's removal into stars, delayed stellar returns and inflow/outflow.
MethodEarth & cosmosFeedback calibration and survey selectionUnresolved star formation, cooling and feedback need declared subgrid closures and calibrated parameter ranges.
MethodEarth & cosmosPerturbed metric, gauge and physical observablesRelativistic perturbation variables depend on the coordinate gauge.
MethodEarth & cosmosEinstein–Boltzmann hierarchy and convergenceAngular moments of photon/neutrino distributions form a Boltzmann hierarchy coupled to metric and fluid equations.
MethodEarth & cosmosPrimordial models, scalar spectra and tensor testsInflationary models relate a stated field action and reheating history to scalar/tensor predictions; observations constrain those predictions rather than identify one unique inflaton.
MethodEarth & cosmosOpen question: unique primordial mechanismA unique microscopic origin of primordial perturbations is not established by the inspected evidence.
Open questionEarth & cosmosDark-matter evidence and candidate testsGravitational evidence constrains additional matter or modified gravitational descriptions under declared assumptions; it does not name a particle.
MethodEarth & cosmosOpen question: dark-matter identityThe dominant dark-matter identity remains unresolved in the inspected evidence.
Open questionEarth & cosmosCosmic acceleration: Λ, dynamical fields and modified gravityAcceleration is inferred through a framework relating expansion and structure to observations.
MethodEarth & cosmosOpen question: physical cause of accelerationThe physical cause of cosmic acceleration remains unresolved in the inspected sources.
Open questionEarth & cosmosLinear poroelastic storage and deformation couplingA quasi-static poroelastic model couples elastic displacement to pore pressure and fluid storage.
MethodEarth & cosmosElectromagnetic parameter maps and primary-secondary sensitivitiesEM inversion links conductivity/permeability parameters to source, fields and receiver response.
MethodEarth & cosmosComparative planetary heat transport and observed phase curvesPlanetary circulation couples radiation and dynamics; comparing advective, radiative and rotation time scales organizes possible regimes.
Method