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Cosmology
Showing 1–18 of 18 reference entries
CMB statistics constrain parameters within a chosen cosmological model.
MethodEarth & cosmosGravitational evidence for dark matterMotions and lensing constrain mass beyond that accounted for by luminous material.
Empirical findingEarth & cosmosWhat constitutes dark matter?Gravitational evidence does not yet settle the unseen component's physical identity.
Open questionEarth & cosmosWhat explains accelerated cosmic expansion?Expansion evidence motivates competing physical descriptions with unresolved origin.
Open questionEarth & cosmosCosmological continuity and constant-w density scalingFor 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 & 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 & cosmosDark-sector models: compare evidence at each scaleGR with cold dark matter is the established cosmological comparison baseline.
MethodEarth & cosmosAcceleration models: fit and independent gravity testsA constant Λ is the minimal GR acceleration baseline; dynamical fields require additional assumptions and parameters.
Method