Just in case you had any doubts, the elite JASON scientists have reported that gravity weapons are impossible.
New Scientist reports:
When the JASON team did the maths, however, results were not good for the plan’s supporters.
The technique is so inefficient that it would take longer than the lifetime of the universe for every power station on Earth to produce a gravitational wave with the energy of one ten millionth of a Joule. Accelerating a spacecraft at 10 metres per second squared, a rate that just exceeds the pull of Earth’s gravity, would require 10^25 times (a 1 followed by 25 zeroes) the electricity output of the world.