We understand from the passage that one of the benefits of Einsteinís relativity theory ----.

Einstein developed his famous theory of ërelativityí
shortly after 1900. It was an enormous improvement
over Newtonís views, since it explained many things
that Newton could not. It showed the close
connection between space, time and gravity. And it
led to surprising predictions. One of them was that
matter and energy could be changed into each other.
The two are simply different forms of the same thing.
This idea enabled man to split the atom and later to
obtain large amounts of nuclear energy.