[Physics FAQ] - [Copyright]

Original by Chris Hillman, 1998.

What Are Some Possible Topics for Discussion on sci.physics.relativity?

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

• 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.