Name: Janet L Rust
According to Einstein, is gravity a force? Does gravity always behave like
a force? Is gravity really a force? If so, why is there not any "antigrav-
ity" in the Universe?
According to Einstein's theory, gravity is not a force. Every form of
energy/mass is a source of gravitational field which appears as the curva-
ture of space-time. Particles move in straight lines in these curved
space-times. These straight lines of curved space-time need not be straight
in flat space we are used to and think in. For example, Earth's orbit
around sun is a 'straight line'!
Jasjeet S Bagla
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Update: June 2012