This category is dedicated to sites about black holes - ultra-compact astronomical objects that are predicted by Einstein's theory of general relativity, whose gravity is so strong that not even light can escape.
Sites that feature material related to the teaching of black hole physics, such as course syllabuses, ideas for class activities and "teacher's kits".
If the focus of a website is on how to teach (how to design a course, what classroom activities to include), it should go in this category. If the focus is on the subject (for instance, lecture notes giving a general introduction to the subject of black holes), they should go in the parent category Black_Holes.
Lists sites containing information about the observational evidence for black holes (stellar dynamics, accretion disks, X-ray observations).
Only websites that focus on the observational aspects of black hole physics should go here - sites with a more general scope should be submitted to the parent category Black Holes.
This sections contains websites with simulations of black holes. Two main classes of websites are included here: The first are research websites dealing with numerical relativity. This includes all attempts to simulate properties of black holes that cannot otherwise elucidated, such as the spacetime geometry around merging black holes or an object collapsing to form a black hole, or the gravitational waves emitted in such situations. The second class encompasses visualization websites, which are more about pedagogy than about black hole research. They feature images and animations to let you see how a black hole looks from the outside, how one can picture the geometry around a black hole, and how the black hole deflects all light in its vicinity.
This category is about the study of black holes as thermodynamic objects (where the black hole mass is inversely proportional to its temperature, and the surface area proportional to its entropy), including quantum effects such as Hawking radiation.
Submissions should focus on research in black hole thermodynamics and Hawking radiation. The websites submitted be based on generally accepted theories and models (for everything else, there''s the category Relativity/Alternative).
Wormholes are hypothetical entities representing sections of spacetime that are warped in such a way as to connect two locations in space and time, possibly over great distances.
Submissions should contain information on wormhole solutions to Einstein''s equations, or on creation and use of such wormholes. Sites which do not have a basis in physics should be redirected to Physics/Relativity/Alternative.