How does Curvature Speed works? Doesn’t it break what we thought was a law of physic?

Question

So there was a huge article months ago where some crazy scientists proved theoretically that a spaceship can reach curvature speed (travel Faster than light)

There was a post here days ago that said that speed is relative and you can’t go further than light because it is the only non relative speed (the example was if you stay on a train that goes 9.8c and shoot a bullet that goes 9.8c you can’t exceed C ). So why would their curvature speed work?

Also, side question, wouldn’t they have to worry about asteroids getting in the way when traveling faster than what they can see?

Also, another question, Would travel faster than light make them go back in time? Since If i remember correctly time depends on light or something, wouldn’t go faster than it transform you in The Flash and make you go back in time, Technically letting you arrive before you started traveling?

In: Physics

Answer 1

Picture space as a big rubber sheet, and you have a remote controlled car with a maximum speed driving across it. What if you wanted that car to go “faster”? One way might be to “squish” the sheet under the car, so that even though the car isn’t actually going faster (in terms of how fast its wheels need to spin), it doesn’t need to travel as far. Then when you arrive, you just unsquish the sheet. You could squish the sheet under the whole path you want to take all at once, but you could also just squish the sheet right under the car as it’s driving. As long as the part directly under the car is always squished, then it’s about the same as squishing the whole path. The article you saw suggests a theoretical way of squishing the universe sheet with extremely large masses.

Regarding asteroids, any asteroids that come into the squished space will be travelling at normal speeds relative to your ship, so you can avoid them as easily as if you weren’t squishing space at all. Inside the “bubble”, everything is travelling at normal, sub speed of light speeds. It’s only the apparent speed (The final distance/time measurement) that appears to be faster than C.