How to colonize the galaxy by using very slow crafts?

  

How to colonize the galaxy by using very slow crafts? 

There is the possibility that we ever can make things like FTL (Faster-Than-Light) technology. But there is another way to travel between stars. And that technology is called "generation ships". Those crafts would reach about 1-20% of the speed of light. 

And that thing means that travel to the nearest solar systems takes even thousands of years. In that version, generations will change inside the craft. And when the journey ends to Alpha Centauri or Bernard Star the people inside that craft are forgetting the Earth. And they might think of their craft as home. 

Those generation ships require lots of genetic material. For denying the genetic matter degeneration. The degeneration predisposes the organism to hereditary diseases. So the crew must modify the genomes of the next generations. So that the variation of the DNA is high enough. 

That craft could be a giant O'Neill cylinder. And when that cylinder travels in interstellar space the rotation movement that forms the synthetic gravitation field will be at a minimum. In that case, the purpose of synthetic gravitation is just to anchor things like vegetables to surfaces. The crew members would be physically very weak. And when the craft closes its target the rotation speed will increase. 

That makes those persons stronger. And when the colonization begins. The rotation speed must be so high. That artificial gravitation is at the level of the targeted planet. So in that case in the middle of that cylinder must be magnets that are making the core resist the centripetal force of fast rotation movement. 

The Tipler cylinder can travel between stars.

If the sum of the speed of rotating plasma and escaping velocity crosses the speed of light. That should make time move backward. So by thinking that way the time travel to both sides is possible. The idea is that when the speed will reach the speed of light. 

That thing causes the time will stop. And if the gravitation field causes that energy level rises higher than the speed of light. That thing makes the time will start to move backward. 

 In that system, the time dilation will be made by using the rotating plasma layer. When plasma rotates a cylinder with the speed of light. That stops time inside that structure. Tipler cylinder can make time dilate and travel to the future. 

But can Tipler cylinder travel to the past? The theory goes like this. If the speed of plasma whirl is the same as the speed of light in a vacuum the craft must just go near some gravitational center like a planet, star, or black hole. Then the sum of the rotation speed of plasma and the escaping velocity must just cross the speed of light. That thing can turn time travel backward. 

When we are thinking about the very slow spacecraft there is. The possibility that the cylinder-shaped craft would be the so-called "Tipler cylinder". The Tipler time machine must not be fast. The system can make time dilation by rotating the plasma around the cylinder. 

Some researchers have introduced a model of interstellar spacecraft, where the O'Neill cylinder will equip with two layers. And between those layers, the magnetic fields will rotate plasma with the speed of light. The system might look like an induction electric engine. In the place of the rotor is the plasma whirl that rotates between stators. 

When the plasma whirl rotates between those layers at the speed of light that thing causes time dilation. This is one version of the futuristic system that can use to travel between stars.