soupphysics wrote:
Actually gravity is not what is preventing long term space travel. It's not a huge problem to go into space.
It's the unimaginable huge distances that prevent it the long trips and the energy needed to accelerate to close to light speed, and even at that speed, it is some very long trips.
Artificial gravity on a space ship is not a problem either. It can be created by rotation (centripetal force).
Remember what happened to the space shuttles Challenger and Columbia? Using chemical rockets to leave the Earth and atmospheric braking to return is too dangerous and inefficient. It also takes far too long to get the shuttle ready for the next flight. Better to be able to control gravity to take off and land gently. We can also use gravity control for air travels.
Accelerating to near light speed is not the only problem. Decelerating when reaching your destination is another problem that also requires a lot of energy. Then there is the time dilation problem.
Rotating a spaceship to create artificial gravity also creates all kinds of engineering problems, such as maintaining balance when internal loads shift from one side to another and stopping and restarting the rotation in order to do exterior maintenance during spacewalks. Then you need a non-rotating section for navigation, ingress and egress purposes.
Gary