Stars might pass through their lifecycle in a matter of weeks. Constellations might deform over days.
Stars might pass through their lifecycle in a matter of weeks. Constellations might deform over days.
But ya, you'd have to be going really #*$&#@ fast.
In the frame of the planet orbiting the hypervelocity star, the rest of the universe is moving at 0.5c, so the planet would measure all clocks in the rest of the universe to be running slower by a factor of 1/sqrt(1-0.5^2) = 1.15. Astronomers on this planet would measure stellar lifecycles (and every other physical process) to proceed slower, not faster.
You have it backwards (easy to do with such a thought experiment!). The direction of time dialation originally stated was correct. Clocks on a body moving at ludicrous speeds will be slower (to the observers present, who are able to look at those clocks) than clocks on a body not moving at ludicrous speeds. Which is to say, if you did a loop around the galaxy at light speed (hypothetical, of course) and came back to Earth and compared your clock with a terrestrial clock, your clock would be waaaay behind, and you would be younger than the people you left behind. This effect is measurable and provable even in the orbit of our own planet (albeit, at a miniscule scale). And so while your time did in fact move more slowly, the overall effect is that you time travelled into the future because everyone else was moving much faster. This of course assumes that you are able to escape intact, which is most unlikely (again, this is just a thought experiment, for argument's sake).
In your defense, I know how easy it is to get turned around in such a thought experiment. Theoretically speaking from the perspective of the par-luminal traveller, it's easy to think "my clock moves slower, so am I slower?" In a way, yes, you are! Your reality moves slower relative to theirs, and for those not travelling at light speed time passes more quickly relative to your time. Objectively speaking, a human lifecycle on a very fast moving planet will equate to many, many lifecycles on a slow moving planet, if all other things are equal. And so while you are truly travelling much faster, your time moves slower, relatively speaking.
Remember as a kid being told about a hypothetical traveller that enters a black hole, and at one point they become a long spaghetti string and then simply freeze in time? That's because they are moving much faster than us, and from the outside looking in they appear to be frozen. The light emitted from their mass is but an echo. They have moved far beyond the light that we see. From the inside looking out, the universe would move much faster.
Again, this is an extreme example used for clarification, but it might not be as extreme as you think. Consider a solar system that gets caught within the grasp of a black hole. Initially the tidal forces tear it apart, but over eons that mass might begin acting like a normal solar system again, and harbor life once more.
If you are travelling fast in a straight line, you will observe the clocks in the entire universe around you running slower. Every clock you watch through a telescope on your ship will be running slow. The entire universe around you will be moving in slow motion.
However, everyone else observing you speeding by in your ship will observe your clocks running slow. They will observe you moving in slow motion.
This is an apparent paradox - in fact, it is the quite famous twin paradox.
The resolution is that this only holds for non-accelerated motion. Flying in a loop around the galaxy requires not just high speed but also a constant acceleration, giving you the additional effects of general relativity, which complicates the situation by quite a lot, but resolves the paradox.
However, an inhabitant on a star moving at relativistic speed through the universe still falls under the original case - the inhabitants on the star will see the rest of the universe moving in slow motion, while the rest of the universe will see them also moving in slow motion.
Very interesting response! Thank you for that. I do see why my comment was misleading now. If you don't mind, could you clarify a few things? I'm just really interested in the subject.
I understand your point about travelling in a straight line: If a traveller were to travel at the speed of light speed away from a theoretical stationary point then both the observers at the stationary point and the observer within the travelling vessel would appear to eachother as frozen (assuming the traveller had equipment to measure the place they left from), because light wouldn't be able to catch up in either direction. That makes sense. When I said "From the inside looking out, the universe would move much faster" I shouldn't have used the term "looking out", that was definitely misleading now that you've mentioned it.
> However, an inhabitant on a star moving at relativistic speed through the universe still falls under the original case - the inhabitants on the star will see the rest of the universe moving in slow motion, while the rest of the universe will see them also moving in slow motion.
Your last statement got me thinking... so let's say there are two equally sized vessels that are somehow able to communicate instantaneously (for arguments sake, let's say the travellers are immortal wizards who have a telepathic link).
Let's say that one of the vessels is caught in the orbit of a black hole and is travelling at nearly the speed of light, and is constantly accellerating as it gets closer to the singularity (ignoring that tidal forces would destroy the vessel, because of it's wizard shielding).
The other vessel is lacadaisically making it's way around a star the size of our own. And let's say that the star and the black hole are slowly drifting away from eachother.
My question is this: Will the wizard inside of the vessel travelling around the black hole age more slowly than the wizard travelling around the normal star? Keep in mind that they will never meet (i.e. never share the same world line), but they do still have a telepathic link and can compare their clocks.
We talk about the "speed of light" being a constant, but this is misleading. The "speed of light" is actually the "speed of causality". Breaking the speed of light, with some theoretical instant communication, would be breaking causality.
In the earlier example, if those two stars each had an emergency beacon that sent you an instant message just as they exploded, you would receive both simultaneously. But the person travelling past you would be very confused about how that could happen, since he clearly observed them exploding at different times.
I do understand what you're saying, and while I agree that observations differ based on the location of the observers, there's one thing that still baffles me. Quantum entanglement.
Let's say that we replace the wizards in my example with a pair of entangled particles, and in fact, for this thought experiment let's pretend that humans and "observers" don't even exist anymore - there is noone left in the universe to observe what is happening anywhere.
Wouldn't our current understanding state that the wave function would be identical between the particles regardless of where those particles are located in spacetime? In effect, wouldn't the wavefunction be "happening at the same time"? Mind you, I'm not suggesting that the particles are communicating, simply that their waveforms are identical. It's really baffling to me that one particle could be in an area subjected to massive gravitational distortion while the other is not (a completely different world line), and yet they are always in sync. Thoughts?
I've read that as well, and I concur that popular opinion states that quantumly linked particles do not appear to violate causality, because we don't believe they are actually communicating at all, let alone communicating faster than light.
The way I interpreted this claim is that those particals are more akin to a deterministic algorithm, which is to say, once you set it free it will always result in the same answer based on the seed. I'm still very confused though about how those particles could remain in sync in vastly different spacetimes. That to me, is a flaw in the conjecture, and one that cannot be tested. We've based our understanding of quantum entanglement only upon that which we can observe, and so we truly don't know if a quantumly entangled particle will be "behind" if it is in a denser gravitational field. It's unprovable, because even if we were to travel into that spacetime, we could not escape to share the results with other observers.
Thank you again for your input. Your argument forced me to mentally reconcile "observable reality" from "actual reality", and that was a fun and intriguing thought experiment, albiet probably pointless since none of it can be proven. Our observations do not define reality, they only measure it to the best of our ability. And most of the time when we measure reality, apparently we fuck it up (i.e. breaking quantum links, or just having incorrect assumptions).
No. When you go fast time slows. Thus the rest of the universe appears to be going faster.
So if you fly away on a spaceship at relativistic speed, then people observing you will see you moving slowly. However, if you observe them from your ship, you will think it is they who are moving slowly.
When he returns all of his friends have aged 50 years. But he has only aged 1 year.
So you see, his friends were aging 50x faster.