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Comment Re:Bad idea (Score 1) 275

But as long as you keep more than 50% of the shares, you still have full control of the company, right? As long as you don't mislead the shareholders (which might lead to lawsuits) and make it clear from the start that this is a long term company which is just taking shareholders along for the ride without them having anything to say, what are the risks for SpaceX?

Comment Re:Bad idea (Score 2) 275

What I don't get is: who cares about hedge fund managers? Just do an IPO for the general public, small investors all over the world are more than eager to pour their money into SpaceX, they are literally asking him for it! Sure, it's a risky investment, and Elon's primary objective doesn't seem to be profit, but why say no to all that crazy excited volunteer funding? Unless he really has all the money he needs right now and wouldn't have any efficient use for more?

Comment Re:Profit! (Score 1) 264

You might be on to something there, if you plan it carefully. The text doesn't say it has to be a justified arrest. So you might indeed say "I pointed a laser at an aircraft", get arrested, then explain "but it was my own plane parked in a hangar", get released, but still qualify for the bounty because you did actually get arrested.

Comment Re:Maybe now, but (Score 1) 358

That's exactly why it would be unlikely that any technological breakthrough would allow us to get to those places. If we can do that, then you can set up a thought experiment sending things back in time by juggling coordinate systems.

Comment Re:Maybe now, but (Score 2) 358

No, those places are accelerating away from us much faster than 1G. Well, depening on the coordinate system you use to calculate that acceleration, obviously. But with cosmological coordinates, yes, way more than 1G and faster than the speed of light. In any case, you will never reach their speed no matter how fast you accelerate, since you can't go faster than (local) light and even light will never catch up with them. Even if you shine a strong laser at them, that light will never get there.

(Assuming our current theories about the inflation of the universe are correct)

Comment Re:FTL or Wormhole Travel (Score 1) 358

I'm just using the term "never" to mean that, with that particular coordinate system, the event does not have a real time coordinate. Maybe an imaginary or infinite one, but not a real one. But if you apply the right coordinate transformation, all of a sudden it's as real as ever. The question whether or not the event is something that will actually exist, is a philosophical one. We will certainly never see it happen, that's all we can really say.

Comment Re:FTL or Wormhole Travel (Score 1) 358

From our pov, it will appear as if time is moving very slowly in their part of space. You might as well have said we don't exist because time is moving slowly here from their pov. Just because the light from the Jurassic is just now reaching some other place, doesn't negate history. The Universe still has a history. It's just the vast majority of it is unknown to us. It's not frozen in a bottle because of inflation.

There is no absolute measure of time in the universe. Depending on your choice of coordinates (special relativistic with us at the center, with some other point at the center, cosmological model, or any other model), distant events can happen in the past, future, present or even never at all. The only thing that matters is interactions between objects. But if events are separated far enough so they cannot possibly have had any causal impact on each other, it's completely meaningless to say one happened before the other or vice versa. Hell, I can make the Andromeda nebula move several years into the future or past simply by getting out of my seat (using a coordinate system tied to my body). That's the beauty of relativity: coordinates are just a way for us to stick numbers onto things and do calculations, but the universe itself doesn't care. That's also why we have such a hard time with general relativity and quantum mechanics.

Comment Re:FTL or Wormhole Travel (Score 2) 358

There's no real center (as far as we know). You can pick any spot and consider that to be "the center" with everything moving away from that spot, but you can just as well pick some different spot.

Of course that's just one theory, with a truly infinite universe. It's perfectly possible that the universe is finite after all, or that it wraps around at some point. It certainly is very big.

Comment Re:FTL or Wormhole Travel (Score 5, Interesting) 358

It's a bit more complicated than that. General relativity allows you to pick any reference frame, even one that is bent, stretched or distorted in some other way, and do your calculations in that reference frame.

You could pick a "normal" reference frame that obeys the special theory of relativity: speed of light constant everywhere, nothing can go faster, etcetera. Nothing wrong with that, but this turns out to be impractical: we have to pick some place to consider as the center of the universe (for example some place in our immediate neighborhood), and then find that the rest of the universe is moving away at very high speeds, approaching (but not exceeding) the speed of light. This means those galaxies are shrunk in the direction of their motion (Lorentz contraction) and time passes more slowly for them (time dilation). The further you "look" (the infinitely quick kind of looking which you can only do inside a theoretical model, not having to wait for light to get here so we can actually see stuff), the more things are shrunk and the slower time is ticking. At a distance of the speed of light ("c") times the age of the universe, things approach the speed of light and time is passing so slowly that the Big Bang is only just happening right now. In this way of describing the universe, with these coordinates the universe actually fits in a finite sphere around us.

That's a perfectly valid set of coordinates, but I think you'll agree it's not very practical. So physicists invented the cosmological model: imagine a bunch of clocks everywhere in the universe, flying at the same speed as the expansion of the universe (i.e. the same speed as average galaxies in that neighborhood) and ticking at whatever rate the local clocks are ticking at (not synchronized to ours). We define time at any place in the universe as being whatever is indicated by those clocks, not ours. So in effect we change the very definition of simultaneity, moving things from the future into today simply by changing the labeling. Also, imagine measuring sticks available everywhere in the universe, but just like the clocks flying at the same speed as the local expanding universe. To measure distances, we use those sticks instead of our own.

If we now measure everything using local (Lorentz-contracted) sticks and local (time-dilated) clocks, the universe looks completely different. It is truly infinite, the same age everywhere, and distant objects are no longer flat Lorentz-contracted pancakes but look the same as objects in our neighbourhood. Note that this is not a different universe, it's the same one but with different labels stuck onto objects.

Now, with this set of coordinates, it turns out that rays of light don't travel at a fixed speed "c" relative to us, but relative to the local clocks and sticks we used to define the coordinate system. It is still true that nothing can go faster than (local) light, i.e. you cannot overtake a ray of light, but a distant object certainly can move away from us faster than the speed of a ray of light in our neighbourhood. And if some alien over there were to try and shoot a laser beam our way, that light would never reach us because it is traveling towards us at the speed of light relative to the local "space" which is moving away from us faster, like a cosmic conveyor belt. Note that this conveyor belt is not real, it's just a product of our mathematical trickery refefining distances and times.

Of course you might wonder what happens to that alien laser beam in the first coordinate system, where rays of light all travel at the same speed relative to us. Well, in that system, the aliens don't exist yet because time in that part of space is moving very slowly (and has been moving slowly ever since the big bang). And since that part of space is still accelerating away from us ever faster and closer to the speed of light, local time comes to an asymptotic halt before the aliens ever get a chance to shoot that laser.

"Space itself" is just whatever we define it to be. By changing coordinates, we can move things from the past into the future or even into "never". It doesn't matter, it's just math(s), the end result is that we will never see that laser and we will never be able to reach that galaxy either.

Comment Re:Maybe now, but (Score 2) 358

The problems are a bit deeper than "we don't have the technology to do it". If we would be able to break these theoretical speed limits, this would automatically imply we would also be able to travel through time or at the very least send messages into the past. That would create a whole bunch of problems for concepts like causality, free will, grandfather paradox, etcetera. Not entirely impossible, I agree, but unlikely nonetheless.

Comment Re:I have just one question, please. (Score 1, Funny) 106

Why does the sound of a Tesla employee farting make a frontpage splash in this site?

What? Did a Tesla employee fart? Where did you read that? I just googled it and couldn't find anything.

Are you just spreading FUD to discredit Tesla? Post a link to a story confirming the fart, or stop spreading these false rumors.

Tesla's stock is slightly up today, by the way, so I assume there's absolutely no truth to what you were saying.

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