The basics of general relativity
The elevator, the rocket, and gravity: the equivalence principle
Information about the principle that Einstein took as a starting point for developing his general theory of relativity
Gravity: from weightlessness to curvature
So what is gravity in Einstein’s theory? The answer: in part, an illusion; in part, an aspect of geometry.
…that all coordinate systems are created equal
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
Inertial and Gravitational Mass
About the different roles played by mass, and the weak equivalence principle
A subtle change in direction: Geodetic precession
In Einstein’s theory, gravity is related to spacetime curvature. This text explores what curvature is – and how the way it influences geometry can be measured directly, with the help of gyroscopes.
