Coincidentally Kobe and others also passed on the Jan. 26 in a tragic accident involving air travel. RIP.

If you change a q-bit its pair also changes instantly no matter where it is in the universe. How does it know? That's information being exchanged faster than the speed of light. Particle physics and quantum mechanics have rules we don't know or understand yet.

What an awesome and insightful question.

Yes, and no.

Let's make a few assumptions. First. Let's assume that both planets are aware of each other and have tech's assumed at each other. Second let's assume that the communication is instantaneous to take out the math issues. Third, only one planet can transmit the messages but the other can recurve them. Finally, assume I'm a random stranger on the Internet and I don't have a PhD in physics.

Both planets are looking at each other and they are seeing photons that bounced off the other planet 4 years in the past. (i.e. they are 4 light years apart) If one planet transmits this instantaneous signal the planet that received the signal will see it as coming from the future because it was transmitted 4 years before the images they are recording on their telescope. So, if they could see the transmitter being built they might see it still under construction for four years after they get the first transmissions.

To the planet transmitting the signal they would get feedback via light speed communications or actual light images in only 4 years rather than the anticipated 8 with communications limited by the speed of light. I think this would look like time dilation rather than time travel to the planet transmitting.

It is not dissimilar to shooting something at long range. If you are the shooter you hear the gun fire and then see the target get hit. If you are standing near the target you see the target react to getting hit long before you hear the gun shot. So, which order you perceive things happening depends on where you are. Of course we are used to the difference in asked between sounds and light so it seems natural but it takes a bit more to shift ourc thinking you you're question

I didn't realize you were referring to that kind of scale. I can't imagine it would mean much seeing as the outer edges of the universe are already expanding away from us faster than light

Been searching around for info on this as I'm heading there this weekend. I'll bring an update back if I see much!

I mean like, that's localized to the Milky Way and the local group. For extra local group travel, it'd basically be impossible.

Information transfer is bound by the speed of light. There is no theoretical possibility of going faster. Your experience of a light beam is going to be the same regardless of it’s speed. You will see it when it strikes your eye.

Time travel can only occur relativistically. The faster a mass moves, the slower time elapses for it.

Wouldn't it appear to travel backwards? The signal appears out of nowhere as it is received and slowly traces backwards to its origin

It's easy to be confident when there's limited information available.

While what you're saying is highly probable based on our current understanding, these two phenomena may be related - it is not absolute. Assumption precludes, and oft forgets, discovery.

> Ever see a ufo?

Well, I have looked up in the sky and saw an aircraft that I couldn't identify, so,....Yea, I've seen a UFO.

It would be interesting to arbitrarily place it at the end of the known universe, and document what's seen from there. Would it mirror our existing views, or maybe provide an unimaginably different perspective?

You could in theory travel to other stars in our star cluster and explore or even live there if you could find a habitable enough planet. That's so far in the future that it really has no practical application other than as an aspiration and inspiration for those doing the work required to eventual get there. There is the other problem of even at twice the speed of light it would still take 2 years to reach Alpha Centauri.

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>Derive - base a concept on a logical extension or modification of (another concept).

In order to derive you must alter the original data. It must change. That is the fundamental aspect of information.

It can change. If it cannot change, it's just data. Not information.

Ok, you've won

>The hypothesis exists therefore there are scientists who at least believe in the possibility that FTL travel is possible

I've always wondered how FTL would help outside of the local group with an expanding universe.

The point is that a lot of learning is done in hindsight. NASA leadership wouldn't make the same mistake today, and neither would I now, but what's done is done. We honor the fallen and hope to improve from their sacrifice.

Change is not a requirement of that. Are you under the impression that "event" means "change"?

Perhaps it has something to do with how much physically closer Challenger was, and the images that were produced because of it. The Challenger vapor cloud is one of those images that is up close and visceral. Columbia's disintegration, not as much.

It would be if it were true. It's not. That's not what entanglement means. If you change the spin of one, nothing will happen to the other. Changing spin breaks entanglement.

You would remove it right when I open the thread

>In information theory, the information content, self-information, surprisal, or Shannon information is a basic quantity derived from the probability of a particular event occurring from a random variable.

That's the definition. Want me to show you where the change is a required part of it?

That is not how it's defined in information theory.

Hello u/KingOfTNT10, your submission "Sending a signal faster than light is time travel?" has been removed from r/space because:

• Such questions should be asked in the "All space questions" thread stickied at the top of the sub.

Please read the rules in the sidebar and check r/space for duplicate submissions before posting. If you have any questions about this removal please message the r/space moderators. Thank you.

If you have two atoms in quantum entanglement, and you change the spin of one atom, the other atom will change it's spin to be opposite. Isn't this the essence of transmitting information?