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Just a thought, does not relate to actual physics

If the universe is really expanding, then if we send probes to distant locations in the universe with earthly data, then will the probes ever reach the desired location or they just will keep travelling, as the time passes, the distance between the cosmic objects too will increase?

Will we need teleportation or speed travelling like shown in star wars to reach different places in the universe?

PS: i am a graphics designer, so forgive my lack of knowledge and if the question is stupid.

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To focus in more parochially, space travel in the near Earth solar system may not be a practical business. It is physically possible of course to build a spaceship that can travel to Mars, but the cost is large. The crew has to be radiation shielded, requiring mass, a Walmart's worth of food and supplies has to be sent along, and so forth. What is not often mentioned is that humans in space are not needed to do space science. Spaceprobes, telescopes, robots and so forth are perfectly capable to performing space science, and at a far lower cost.

What is needed is an economic purpose for putting humans in space. Maybe solar power satellites in geosynchronous orbit or asteroid mining will provide an economic reason to put humans in space. So far as I know the return on investment in such activities has not been analysed sufficiently to be demonstrated as positive. So far the whole enterprise of manned spaceflight appears to be stalled, and the only thing going on is the ISS in Earth orbit, which at best is really a space-based diplomatic system than anything that performs any real science.

Interstellar space travel is a huge expansion on interplanetary space travel, and they by enormous expansion again we could talk about intergalactic travel. The future prospects for these things is problematic. However if that should ever occur there are cosmological limits. Anything closer than the cosmological horizon can be reached with a light signal, and so a hyper-relativistic spaceship could reach anything up to a region close to the cosmological horizon. There is a lot of universe inside this region, such as tens of billions of galaxies. I am assuming that Hawking-Penrose energy condition violating spacetimes such as wormholes or warp drives are not possible.

Teleportation only works if Bob, who exchanges out his half of the EPR with another state, sends a classical signal to Alice how this state is to be measured in the same basis Bob measures in. This signal tells Alice how to orient her Stern-Gerlach apparatus, or similar thing, so she reads out the teleported result properly. Without proper orientation the outcome appears as noise. In the case of cosmology it is not possible to send a signal beyond the cosmological horizon. Alice must also carry her half of the EPR pair there in the first place, which requires relativistic travel to the cosmological radial distance $10^{10}$ light years and then be frame dragged in a comoving coordinate system beyond this region. So teleportation is not a practical method for getting around cosmological limits.

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  • $\begingroup$ Well i do not have a physics background, so i could not understand your answer. Sorry for the trouble, but can u please shorten it and dial it down for me ? $\endgroup$ Sep 19, 2016 at 12:09
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    $\begingroup$ To make it easy, travel between stars is theoretically possible. I am not sure how possible this is from a practical perspective. but traveling within a local region in this galaxy with relativistic spaceships is plausible. Traveling to other galaxies is harder and would require even higher relativistic effects. However it is not possible to travel to galaxies beyond the cosmological horizon or with a $z~>~1$. Even teleportation is not possible. $\endgroup$ Sep 19, 2016 at 14:54

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