Lieu started out trying to find another solution to the Einstein field equations ... "But it is the first [mathematical] proof that gravity can exist without mass." The study has been published ...

In a recent discussion on the Tucker Carlson Network, Dr. Willie Soon, an astrophysicist and aerospace engineer from Harvard ...

There are various methods to measure acceleration due to gravity. At Higher level all rely on one of the equations of motion. The measurements required will depend on the equation used.