It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.

Depends on who you mean as "we". The speed of light isn't a speed limit. If you can create a ship that is capable of 1g acceleration, it doesn't just stop accelerating as it reaches the speed of light relative to some stationary object, like Earth. Instead you start getting relativistic effects and things start getting very weird with time and distance doing some funky stuff. You keep zooming along just fine from your perspective, but an at-rest observer on Earth would see your ship asymptotically approach the speed of light, but never exceed it. The universe is very weird. In any case you could viably travel billions of light years in a single human lifetime, but for an observer at rest billions of their years would genuinely pass. In other words, traveling into the future is very much a real thing, so far as our current understanding of the universe goes.

The search term on this is 'relativistic starship.' Here's [1] a calculator to see what the math works out to for a ship capable of accelerating at 1g indefinitely. So for instance you could travel to Andromeda, some 2 million light years away, in about 28 years. But 2 million years would really pass for those at relative rest, such as those on Earth. So if you came back, the humanity you found (if any) would be unimaginably different.

And this isn't some just some weird fringe theoretical/mathematical thing. For instance GPS satellites have to compensate for time dilation because relativistic effects would otherwise have a substantial effect. Another example is at things like the large hadron collider. As a convenient effect of relativistic effects, emergent unstable particles exist far longer than they 'normally' would before decaying due to the fact they're moving at relativistic rates.

[1] - http://www.convertalot.com/relativistic_star_ship_calculator...

Relativistic starships are impossible because they require impossible amounts of fuel. "If you can create a ship that is capable of 1g acceleration" is doing a lot of heavy lifting. The rocket equation means you need to take along exponentially increasing amounts of fuel

Even antimatter rockets top out at 50% of light speed. Laser boost like with Dyson Swarm could get similar speeds because time dilation slows down the acceleration.

This isn’t gonna work, space isn’t truly empty. Even with antimatter propulsion the interstellar medium will start to vaporize your ship at speed above 0.2c.

> If you can create a ship that is capable of 1g acceleration, it doesn't just stop accelerating as it reaches the speed of light

For any object with nonzero rest mass, reaching exactly the speed of light in vacuum would require infinite energy.

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Even if FTL is achievable (which I agree, highly unlikely), it's still extraordinarily slow on cosmic scales. The closest star is a little over 4 ly away!

And probing the universe outside the Milky Way? Forget about it.

1. if FTL is achievable, then presumably it isn't limited to 1.00000000001 x C

2. I like to think about the size of the universe by always remembering that with the naked eye, on a good night, there's only a single object in the entire night sky that isn't in our galaxy (M3, the Andromeda Galaxy).

We are still so slow and have had space travel for so little time, we are almost certainly on the "wait" side of the wait equation: https://en.wikipedia.org/wiki/The_Wait_Equation

The entire universe seems to be inside a giant black hole, anyway, and the more it goes, the more evidence is found to support that. Might as well find a black hole and visit other universes than explore our own.

The next known black hole is tens of thousands of light years away. Also, the universe does not seem to be inside a black hole.

What definition of black hole are you using?

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It would help if our science wasn’t distracted by things like global warming and nazi governments though. There are definitely ways we can help the process * right now *

Good luck doing anything on any other planet if you can't even handle your own that's perfectly suited for your kind of life form.

Yeah, let's ignore current issues and instead focus on remote stars.

Scientists and engineers with an interest in such things would have an easier time working on it, if the broader economic and civic context they work in wasn't being messed with by demagogues.

They shouldn't be drafted to resolve the rise of petty tyrants. It's a waste of their time.

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the message you replied to implied the exact opposite.