Question

It combines special relativity with the equivalence principle.

Answer 1

The equivalence principle was Einstein's `Newton's apple' insight to gravitation. ... The equivalence principle is a fundamental law of physics that states that gravitational and inertial forces are of a similar nature and often indistinguishable.

Answer 2

It combines special relativity with the equivalence principle.
The equivalence principle was Einstein's `Newton's apple' insight to gravitation. ... The equivalence principle is a fundamental law of physics that states that gravitational and inertial forces are of a similar nature and often