Original by Chris Hillman September 1998.

Specific topics suitable for discussion in sci.physics.relativity include, but are not limited to, the following:

(SR)- time dilation and Lorentz contraction,
- relativity of simultaneity,
- Minkowski geometry, spacetime, world lines,
- the energy-momentum four-vector,
- proper time,
- hyperbolic trigonometry,
- light cones and the absolute past and future,
- Lorentz transformations, the Lorentz and Poincare groups,
- the Thomas precession,
- relativistic optics, the Penrose-Terrel "rotation",
- relativistic starflight,
- "paradoxes" in SR,
- experimental tests of SR,

- the nature of the Hubble expansion and the Big Bang,
- the observable Universe,
- the cosmic microwave background radiation,
- Friedmann dust, Tolman fluid, Goedel dust, etc.,
- gravitational lenses,
- interpretation of astronomical observations,
- the cosmological constant,
- the inflationary scenario,

- gravitational collapse and black holes,
- neutron stars, relativistic stars, compact objects,
- collisions of black holes,
- collisions of gravitational waves,
- relativistic orbital dynamics,
- extraction of energy from black holes, Penrose process,
- comparison of astrophysical observations with the predictions of GR,

- tensors,
- curvilinear coordinates, coordinate patches,
- manifolds, submanifolds, embeddings,
- tangent planes, tangent bundles, vector and tensor bundles,
- differential geometry and differential topology,
- connections, holonomy,
- covariant derivatives, Lie derivatives, exterior derivatives,
- geodesics, geodesic deviation,
- curvature,
- intrinsic versus extrinsic geometry,
- global versus local features,
- invariants of tensors,
- Bianchi classification of three dimensional homogeneous manifolds,

- the geometry of GR,
- the equivalence principle,
- gravitational redshift and time dilation,
- the metric and strain tensors,
- the matter tensor and its physical significance,
- the Riemann, Ricci, Einstein, and Weyl curvature tensors,
- the Petrov classification of vacuum solutions,
- the nature of the field equation and its physical significance,
- mathematical characteristics of the field equation,
- methods of solving the field equation,
- exact solutions (e.g. the Schwarzschild solution),
- the relation of GR to newtonian and other theories of gravitation,
- the nature of energy, angular momentum, entropy, etc. in GR,
- relativistic dynamics of test particles,
- weak-field theory, linearized GR,
- gravitational waves, design of liGO and other detectors,
- event horizons,
- curvature singularities,
- electromagnetism in GR, Einstein-Maxwell solutions,
- frame dragging, Lense-Thirring effect,
- gravito-electric and gravito-magnetic parts of the curvature tensor,
- shear, vorticity,
- Mach's principle,
- uniqueness theorems, stability theorems, and singularity theorems,
- numerical simulation (ADM, YCB formulations of GR),
- comparison of experimental results with the predictions of GR,

- Hawking and Unruh radiation,
- semiclassical quantum field theories (QFT's),
- black hole thermodynamics,
- dilaton fields and Yang-Mills fields in GR,

- Kaluza-Klein theories,
- quantum gravity,
- black hole entropy and the information paradox,

- the history of physics as it relates to relativity theory,
- the philosophy of physics as it relates to relativity theory,
- warp metrics, superluminal travel possibly consistent with GR,
- the "arrow of time" as it relates to cosmology,
- Olber's paradox,
- reviews of relativity books, suggestions for relativity textbooks,
- suggestions for designing a course of self-study,
- discussions of graduate programs in relativity.

Many of the above topics are likely to be completely unfamiliar to most newcomers--don't let that scare you off! Relativity is a big, big subject, and you will find detailed suggestions for further reading and a "codebook" explaining some commonly used abbreviations for particular textbooks, such as MTW) in the FAQ.