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Showing 1441–1470 of 1709 reference entries

Earth & cosmosReactive geochemical transport and activity models

Reactive transport couples species fluxes to kinetic/equilibrium reactions while enforcing elemental and charge balance.

Method
Earth & cosmosUnsaturated flow, constitutive curves and coupling

Richards flow conserves water in a variably saturated porous medium while Darcy flux uses saturation-dependent permeability.

Method
Earth & cosmosGroundwater and poroelastic effective stress

Coupled groundwater and deformation models account for pore pressure, body forces, elastic response and boundary conditions.

Method
Earth & cosmosCoupled incision and sediment conservation

Shared stream-power models combine detachment and transport limits instead of identifying sediment flux with erosion.

Method
Earth & cosmosIce enthalpy and thermal-rheological coupling

Ice thermal models combine advection, diffusion and deformation heating; enthalpy tracks sensible heat and liquid fraction at the pressure-melting boundary.

Method
Earth & cosmosCrack geometry, stress intensity and energy release

Mode-I stress intensity depends on load and crack geometry.

Method
Earth & cosmosRate-and-state friction and fault stability

Rate-and-state friction distinguishes instantaneous velocity response from state evolution.

Method
Earth & cosmosMantle forward models and adjoint sensitivity

Mantle reconstruction solves mass, momentum and energy equations with rheology and thermal boundaries, then uses observations to constrain a past state.

Method
Earth & cosmosIce loading, mantle rheology and glacial isostatic adjustment

Glacial isostatic adjustment jointly depends on ice/ocean loading history and Earth's elastic-viscous response.

Method
Earth & cosmosCore dynamo equations and parameter extrapolation

Rotating dynamo models couple magnetic induction, momentum, heat/composition transport and solenoidal constraints.

Method
Earth & cosmosDynamo power budgets and competing scaling laws

A statistically steady dynamo with no net mechanical or Poynting power through its boundary balances supplied buoyancy power against ohmic and viscous dissipation.

Method
Earth & cosmosEarth-system ensembles and experimental design

Earth-system simulations couple atmosphere, ocean, land, cryosphere and biogeochemistry.

Method
Earth & cosmosPaleoclimate proxy assimilation and withheld validation

Paleoclimate reconstruction combines proxy calibration/age support with a climate-model prior.

Method
Earth & cosmosPrecambrian plate circuits and observation-constrained alternatives

Deep-time full-plate reconstructions combine paleomagnetism, geological ties and evolving topological boundaries.

Method
Earth & cosmos2026 study: automatic viscoelastic Earth adjoints

Scott et al. extended G-ADOPT to elastic-compressible, laterally variable and non-Maxwell viscoelastic models.

Method
Earth & cosmos2026 preprint: GPU mantle-convection benchmarks

The TERRA-NG v1.0 preprint reports a matrix-free GPU Stokes–energy solver specialized for spherical wedges and tests against a spherical-shell convection benchmark.

Method
Earth & cosmosKepler ellipse timing and anomaly conventions

An elliptic two-body ephemeris solves Kepler's equation for eccentric anomaly at a declared time origin, then transforms orbital-plane coordinates to the observing frame.

Method
Earth & cosmosSafeguarded Kepler root solving and observation uncertainty

For an elliptic orbit, d(E-e sin E)/dE is positive, so the root is unique for a chosen unwrapped mean anomaly.

Method
Earth & cosmosProjected baseline, delay and complex visibility

A far-field source produces a geometric delay b·s/c between two antennas.

Method
Earth & cosmosVisibility sampling, smearing and calibration

An interferometer measures a finite set of Fourier samples, leaving unmeasured sky modes.

Method
Earth & cosmosCollisionless phase-space transport

A collisionless distribution follows Hamiltonian trajectories in a mean gravitational potential.

Method
Earth & cosmosSpherical Jeans equation and anisotropy

The stationary spherical nonrotating Jeans moment equation connects tracer density and radial velocity dispersion to enclosed mass through velocity anisotropy.

Method
Earth & cosmosLine-of-sight Jeans projection and boundary closure

A projected dispersion averages line-of-sight moments through the tracer system.

Method
Earth & cosmosStellar structure as a coupled boundary problem

Discretize stellar structure, transport and composition into a residual vector F(y).

Method
Earth & cosmosEOS interpolation, atmosphere matching and model domains

A stellar or planetary EOS can blend differently valid microscopic models.

Method
Earth & cosmosPlane-parallel transfer moments and angular closure

Angle-dependent radiative transfer yields moments J,H,K; flux is 4πH.

Method
Earth & cosmosStatistical equilibrium beyond LTE

NonLTE level populations solve coupled radiative and collisional rate equations with particle/charge constraints and the transfer solution.

Method
Earth & cosmosRotating stellar grids and convection uncertainty

Shellular stellar evolution approximates angular velocity as nearly constant on isobars and models vertical transport and mass loss with prescriptions.

Method
Earth & cosmosIdeal magnetic-fluid induction and divergence

Ideal conducting-fluid motion evolves magnetic flux by induction and preserves an initially solenoidal field.

Method
Earth & cosmosMagnetic stress, tension and Alfvén response

Magnetic pressure and tension contribute a stress tensor whose divergence gives the Lorentz force in the stated quasistatic limit.

Method
MethodSource checked

Spherical Jeans equation and anisotropy

Earth & cosmos

Research context

research method · conditional · As of 2026-10-10

The stationary spherical nonrotating Jeans moment equation connects tracer density and radial velocity dispersion to enclosed mass through velocity anisotropy.

Key knowledge

The stationary spherical nonrotating Jeans moment equation connects tracer density and radial velocity dispersion to enclosed mass through velocity anisotropy. Its outer-pressure boundary enters the solution. Different mass and anisotropy profiles can reproduce the same projected dispersion.

Values and equations

d(ν σr^2)/dr + 2βνσr^2/r = -ν G M(<r)/r^2; β=1-(σθ^2+σφ^2)/(2σr^2)

ν
Tracer number density m^-3
σr,σθ,σφ
Velocity dispersions m s^-1
β
Velocity anisotropy 1
M(<r)
Total gravitating mass inside r kg
r
Spherical radius m
G
Gravitational constant m^3 kg^-1 s^-2

Conditions and scope

  • Require collisionless approximate equilibrium, spherical symmetry and a known tracer profile.
  • Streaming, tides, binaries and interlopers need additional terms or observation models.
Sources · 1

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. The Jeans equationsJo BovyReference guidegalaxiesbook.orgRead source

Evidence and review

The Jeans equations: Spherical nonrotating moment equation, anisotropy and boundary integral (selected source body inspected).

2026-10-10 · Bounded source check of the recorded statement and conditions. This does not certify a unique physical model, reproduce the cited study or replace independent branch review.

Entry detailsPermanent link to this entry ↗
Record identity
research-earth-spherical-jeans
Revision
research.1
Structured reference record
Postgraduate & research reference