- Beyond Einstein - Description of NASA's Beyond Einstein missions set to explore various consequences of general relativity - and possibly, as the name indicate, go beyond what Einstein's theory predicts. Includes educational resources.
- The Light Cone: An Illuminating Introduction to Relativity - Introduces the basic principles of relativity, the physics of special relativity, and some basic principles of general relativity. Contains a great number of helpful images and animations; site created by Rob Salgado (Syracuse University).
- Relativity - Provides information on the history, experiments and paradoxes of relativity.
- Relativity bookmarks - Large collection of relativity-related links by Rob Salgado (Syracuse University). Warning: page hasn't been updated since 2000, and quite a number of links are now broken.
- Interactive Experiments in Gravity - Try an experiment that illustrates the gravitational attraction between two objects or use a Java applet to understand how orbits work in strongly curved space-time.
- Wikipedia: Introduction to General Relativity - Encyclopedia article explaining the basic concepts, observational tests and (astrophysical) applications of general relativity.
- Physics Bookshelf - Relativity - A collection of articles about relativity
- Introduction to General Relativity - By Gerard 't Hooft (Utrecht University); based on lectures held in 2002; a thorough introduction starting with accelerated frames and including topics such as black holes, the basics of cosmology, and gravitational radiation.
- Relativity: List of Important Equations - Page scans from the Handbook of Space Astronomy and Astrophysics giving equations and formulas for special relativity and relativistic cosmology. Includes bibliography.
- Spacetime - General Relativity, Quantum Gravity, and the Existence of Time - A brief summary of Spacetime Theories at the beginning of the Third Millennium, and of the possibility that we live in an essentially atemporal universe.
- An Essay on General Relativity - Overview of the basic ideas and principal applications of general relativity. Written by John L. Safko for students in the self-paced astronomy courses at the University of South Carolina in 1997.
- Interactive Geometric Database - Interactive database developed by Mustapha Ishak and Kayll Lake and hosted by Queen's University; allows the user to search for specific solutions of Einstein's field equations (that is, for specific model universes of general relativity).
- QMW Hyperspace - A set of hypertext based services for general relativity research provided by the QMW Relativity group.
- Wikipedia: General Relativity Resources - Annotated list of reading material about general relativity: popular books, textbooks, books on specific topics, web courses, and websites.
- NOVA Online/Einstein Revealed - Profile of Albert Einstein, with additional teaching resources, Shockwave demonstrations, and animations of relativity concepts.
- Cambridge Relativity Public Home Page - Various pages with non-technical texts about cosmology, black holes, cosmic strings, inflation, quantum cosmology, and string theory, written by members of the Relativity Group at Cambridge University.
- Einstein Online - Information about Einstein's theories of special and general relativity and their applications; site is hosted by the Max Planck Institute for Gravitational Physics. Includes a simple introduction, a collection of articles ("Spotlights on relativity"), and a relativistic dictionary.
- Relativity: Special, General, and Cosmological - Sample chapters from the classical textbook by Wolfgang Rindler, as part of a "limited preview" on Google Books.
- Are There Any Good Books on Relativity Theory? - The Physics FAQs guide to relativity books; by Chris Hillman (with contributions by Nathan Urban). An extensive annotated list of semi-popular books, textbooks and background reading.
- The Physical Construction of Time - Papers by Igor Zlobin that analyze time deceleration effect as predicted by both relativity and special relativity theories. Some papers are in English and Russia, others only in Russian.
Media publications
- Subtle is the Gravity - Review of the motivations for and basic principles of general relativity, aimed at a general audience. Written by Naresh Dadhich (IUCAA Pune), based on a lecture delivered in 2001. (Published 2001-02-03 00:00:00)
- General Relativity Simulation Contest - Attempt at a content aimed at the Internet community to write a simulation program, based on a simple algorithm incorporating the laws of general relativity, that can realistically simulate the behavior of black holes, binary stars, and the twin paradox. (Published 2005-12-28 00:00:00)
- Numerical Relativity: Status and Prospects - Review article by Luis Lehner about the foundations of numerical relativity and recent progress in the field; particular attention is paid to simulations of black hole spacetimes. (Published 2002-02-19 00:00:00)
- Gravitational Waves and Black Holes: An Introduction to General Relativity - An introduction by Jan-Willem van Holten (NIKHEF, Amsterdam), based on lectures given at the University of Heidelberg in 1997. (Published 1997-04-15 00:00:00)