— filed under: g-spotlight-c2
Foundations of Einstein's theory of gravity: Einstein and soap bubbles, what is a source of gravity, the equivalence principle and free fall
This page features an overview of all our Spotlights on Relativity dealing with the basic features of general relativity. The spotlight texts under the heading Fundamentals deal with the equivalence principle, the equal rights of all observers and the question which properties of a body determine its gravitational influence. The section General relativity and light examines gravity's influence on the propagation and properties of light, while Singularities takes a look at some of the theory's more disturbing predictions for the interior of black holes and the beginning of our universe. The mathematics of general relativity is all about the more mathematical aspects of Einstein's theories - from the surprising connection to the theory of soap bubbles to the question of how much variety Einstein's equations admit. The focus of the section Numerical relativity are computer simulations of complex relativistic phenomena, such as merging black holes. Under Miscellaneous, there is a text on the relativistic Nobel prizes.
Many more Spotlights concerned with specific consequences and applications of general relativity can be found on the overview pages Gravitational Waves, Black Holes & Co., Cosmology and Relativity and the Quantum.
The basics of general relativity
Information about the principle that Einstein took as a starting point for developing his general theory of relativity
So what is gravity in Einstein's theory? The answer: in part, an illusion; in part, an aspect of geometry.
Why, in general relativity, all observers are on an equal footing - and why, nevertheless, you can say that the earth orbits the sun, but not the other way around
Mass and other sources of gravity
An account of which physical properties act as sources of gravity - includes consequences for collapsing stars and for cosmology
An important property of gravity in Einstein's theory is that it can create more gravity. The result is "non-linearity" - the gravitational influence of two bodies isn't just the sum of their separate influences!
Light in general relativity
On one of the fundamental consequences of general relativity: the deflection of light by gravity
The connection between one of the fundamental principles of general relativity and the gravitational deflection of light
Historical sketch of the derivation of general relativity's prediction of gravitational lenses and subsequent astronomical observations
One of the fundamental effects predicted by general relativity, and some of its astronomical applications
Information about the most disturbing feature of Einstein's theory - ragged edges of spacetime known as singularities.
About some characteristic properties of spacetime near singularities - and the violent deformations they cause for any object unlucky enough to approach a singularity
Modeling relativistic fluids and the phenomena associated with them - from supernovae and jets to merging neutron stars
From Newton to Einstein - and beyond
Information about a modification of Einstein's theory of general relativity in which the gravitational constant is not a constant.
The mathematics behind general relativity
Most readers will know them from childhood: soap bubbles
More information on one particular answer to the question of how much variety is permitted in general relativity - how many ways are there of constructing a universe that is completely empty of all matter?
An overview of Nobel prizes connected with relativistic physics