News for hackers. Stuff that matters.

A comment on The tyranny of the rocket equation (2012). Parent comment

Re:The tyranny of the rocket equation (2012) by michaelmrose on Tuesday September 06, 2022 @05:25AM (#32734787)
Gravity is the shape of spacetime. Why would antigravity be a thing.
[ Parent | on HN ]
Re:The tyranny of the rocket equation (2012) by forgotpwd16 on Tuesday September 06, 2022 @06:40AM (#32735254)
Can be a defect in spacetime. See: https://arxiv.org/abs/1803.09736
[ Parent | on HN ]
Re:The tyranny of the rocket equation (2012) by YesWeWill on Tuesday September 06, 2022 @05:51AM (#32734942)
Alcubierre drive essentially changes the shape of spacetime, doesn't it?
[ Parent | on HN ]
Re:The tyranny of the rocket equation (2012) by mr_mitm on Tuesday September 06, 2022 @06:58AM (#32735376)
Everything (that has mass or energy) changes the shape of spacetime.
[ Parent | on HN ]
Re:The tyranny of the rocket equation (2012) by YesWeWill on Tuesday September 06, 2022 @08:34AM (#32736256)
Sure, my point is that the changes made with Alcubierre drive are controllable.
[ Parent | on HN ]
Re:The tyranny of the rocket equation (2012) by simiones on Tuesday September 06, 2022 @09:07AM (#32736588)
Not really. The Alcubierre "drive" is closer to a "shape", a static solution to Einstein's equations. There is no proposed device that actually achieves this shape. The only idea along those lines implies a kind of Alcubierre railroad - you set up a path of negative mass matter (which almost certainly doesn't exist) and then move this with regular means as the ship is approaching, thereby continuing the bubble for the ship.
[ Parent | on HN ]