Gravity doesn't have a frequency. Gravity is an effect of motion...or rather a slowing of motion.
It works like this: The entire universe is expanding. This means that our reality, all matter, space and time is expanding.
However this expansion gets "slowed" by all objects. Think of the objects as "grabbing" space time near them and slowing it down. However it takes truly massive objects to slow down this expansion.
Take the sun...it slows down the expansion quite a bit. What we call "gravity" around the sun is really a slowing down of the general expansion of space/time. All objects within this local slowdown of space time are caught in this area of slow down.
Same way with the earths gravity. We escape the earth's gravity when we go faster than how much earth is slowing down space time in it's region.
That's why there's time dilation when we travel faster...the faster we go the more we "catch up" to the general rate of expansion of space time.
So in order to time travel we would have to invent something that would "grab" spacetime and practically stop the expansion of space/time within a limited area.
SO.... if it weren’t for the SUN, we would all be immortal.
Where did you get that from?