If gravity is a distortion in space-time, why do we call it a force?
A force is something that causes a body to change its velocity. In relativity, space-time is
the 'field' that defines how strong gravitational forces will be, just as the electromagnetic
field defines how strong electric and magnetic forces will be. We are embedded in the gravitational
field of the cosmos just as an electron is embedded in the electromagnetic field. Changes in the strength
of this field from one place to another are what we experience as a gravitational force, just as changes
in an electric field causes electric forces. Fields that have the same strength from place to place in
space cause no forces. For gravity, it is the change in the curvature or 'warpage' of space from place to
place that produces a gravitational force, but even with no curvature, the gravitational field is still present.
It better be, because according to general relativity, the gravitational field is another name for the thing we
call space itself. If you do away with the gravitational field of the cosmos, space and time vanish out of existence completely!
