Talk:Intergalactic travel

message: Why can't we conceive the technical possibility of intergalactic travel? After all, even interplanetary travel or going to the moon would be unconceivable only 500 years ago.
If effective propulsion methods are not known, it doesn't mean that they can't exist at all.
Anyway, even interstellar travel is speculative, and that may be one reason why there is no evidence that we are visited by aliens. Even with a wide range of theories supporting the possibility of interstellar travel, it might not be useful or practical at all.
Probably, it's even less useful or practical to make intergalactic trips, but theoretically it may be possible in the future, as science and technology advances. I don't think it's correct to discard it on the basis the is a highly fantastic speculation.
Concerning to the speculation's criticisms, it must be pointed out that every theory is speculation before it's proven. So, if scientists in history wouldn't have been open to speculation at all, we would still be in the middle ages or at an even less advanced stage in our society.
It would be also interesting to see if space travel will continue to be in fashion in the future, since Earth is plenty of resources and wastes a lot of energy that comes from the Sun, which is not used at all for direct human benefit (apart from maybe 0,1% or less). When our curiosity about the Solar System and the Universe is satisfied, through means that don't necessary imply going there, will humans be still interested about that? We can not know it now, as we can't know either if science and technology will ever allow the possibility of intergalactic travel  —Preceding unsigned comment added by Nmgscp (talk • contribs) 18:10, 2 October 2007 (UTC)
thread_title:  Why not? 

message: The last sentence doesn't make sense. It says 'useful for intergalactic travel, and maybe even interstellar travel' .. obviously the latter would be simpler than the former..  —Preceding unsigned comment added by 75.72.21.221 (talk) 04:09, 18 October 2007 (UTC)
thread_title:  Um, 

message: Interesting article:
http://www.wired.com/science/space/news/2008/08/space_limits  —Preceding unsigned comment added by 65.118.33.162 (talk) 14:39, 21 August 2008 (UTC)
thread_title:  Reference 

message: It would be interesting to have a list of what if ANY science fiction involves intergalactic travel. The reference to Star Trek is a bit misleading; the entire series takes place almost entirely within a section of the Milky Way. -Craig Pemberton 22:33, 26 December 2009 (UTC)
replies: text: Interesting, perhaps; but as of this date the article is merely a stub and is lacking in all aspects, the article should at first try to make a much more solid description with i.a. the associated technologies, physics and mathematics thereof prior to start including mere trivia. Posix memalign (talk) 01:19, 19 February 2010 (UTC)
thread_title:  In Science Fiction / In Popular Culture section 

message: is that if current human understanding about travel faster than c is false, then there is no apparent reason to distinguish interstellar from intergalactic travel. OTOH were there some way to accommodate issues from travel at c, then incremental distances traveled would be significant, centrally as a result of time dilation (the enabling issue) but also as engineering issues. Nonetheless, even assuming just near luminal velocity travel, from the frame of the traveler, ignoring temporal displacement, intergalactic vs. interstellar is not necessarily the great leap depicted. 72.228.177.92 (talk) 01:21, 17 February 2010 (UTC)
replies: text: I dispute that; interstellar travel to the very nearest stars can be thought perfectly feasible in concept with generation ships and rather conventional technologies without approaching c enough to gain the benefit of time dilation -- i.e. at a v : c > v >> [Voyager 1] where the travelers are not affected to a noteworthy degree of time dilation. Hence as interstellar travel can be achieved with a completely different era of technology as compared to intergalactic travel it is thus fair to depict it as a great leap. Posix memalign (talk) 01:16, 19 February 2010 (UTC)
replies: text: Yes from that perspective that's true, but I discount the whole idea of the independent development of means to travel to nearby stars because I presume that before that could be effected there will be a Discovery of Earth by a cosmopolitan culture which has "solved" these problems and which I identify with the technological singularity or omega point of culture. Also, the nearest stars at the velocity you mention will require round trips of at least ten years and my presentiment is that said singularity will occur before that. There is another alternative which is that there is no other life of superior intelligence in the universe or the cosmopolitan culture I refer to has yet to be established but that is a branch of reasoning I discount just based on the numbers and application of the Copernican principle. We should know this within the next few decades, i.e. substantially before we could, from where we are now, field expeditions or even unmanned probes to the nearby stars. 72.228.177.92 (talk) 04:19, 20 February 2010 (UTC)
replies: text:  An unmanned probe to the nearest systems is within current capabilities purely on a technological basis but this is somewhat besides the point because mounting such a project is outside of the range of possibilities given the current level of human political and social development. Again, the change in that underlying condition, I propose, will merge with the general cultural singularity referred to above.  Also there should be a mention of why intergalactic travel is more interesting than merely interstellar: i.e. that it makes the entire universe available for contact with other intelligent species, not just this galaxy, but the 100 billion or so other ones as well. 72.228.177.92 (talk) 13:44, 20 February 2010 (UTC)
thread_title:  The Main Factual Point 

message: There has been major developments in the field of warped empty space in terms of popular theory.  NASA scientists have calculated that in order for the objects in our universe to be as spread out as they have, within the time frame from the big bang till now, that the big bang would of had to push physical objects faster than the speed of light.  Empty space itself does not have a speed limit because empty space has no density or mass.  This leaves us with the question of well if we cannot physical travel as fast as the speed of light or faster, why not cause the empty space behind an object to expand and the empty space in front of the object to contract faster than the speed of light?  Basically causing a wave in the local area of empty space, in front and behind the object, to move in conjunction with each other faster than the speed of light to propel the object in the bubble of still (not moving) space between the empty space warps to move faster than light because technically the object and space inside the bubble is not moving and just the localized space in front and behind the object is.  This is a theory many physicists share, the only problem is discovering how to manipulate gravity and/or dark matter to expand and contract the empty space (The Large Hadron Collider is currently being used to try to understand the physics of gravity and dark matter/energy). Of course even when we figure out how to manipulate empty space we still run into the problem of how to power such a massive reaction, but one day we will have the ability to create more energy than we can currently imagine.  So I would not call the idea of moving faster then the speed of light impossible, just currently out of reach.15.211.201.83 (talk) 23:07, 26 June 2013 (UTC)
thread_title:  Beyond the Speed of Light (FTL Speed) 

message: I don't quite have a perfect understanding of the issue, but is it not the case that over a journey of many millions of years at near light speeds the expansion of the universe would become a significant factor in the journey? This KurzGesagt video implies that such a trip would in fact be impossible due to the expansion of the universe. I'm skeptical about their claim, but certainly you can never reach anything outside your Hubble volume. Can anyone shed light on this issue? Nolandda (talk) 04:09, 20 June 2016 (UTC)
thread_title:  Issues related to expanding space-time 

message: Interstellar travel. What about a merge? Kortoso (talk) 18:30, 3 December 2015 (UTC)
thread_title:  Possible duplicate article 

message: Should this section perhaps be deleted? While it might be easy to assume that a trip to another galaxy would be a one-way trip, it is also possible that it might not be. Currently it is only speculation in any case as we do not know anything about the state of technology at a point in time when intergalactic travel could be done. Let's say it was a trip to the Andromeda galaxy 2.5 million light years away. If humans were to be sent on such a trip they might be uploaded to computers, be genetically engineered, cyborgs etc and might be able to survive the trip. For the sake of argument let's assume the average speed of the spacecraft was 50% of the speed of light, then the trip would take 5 million years there and another 5 million years if they were to return (earth time, on-ship time would would be less). We also currently do not know if faster than light travel is possible.
The only thing we can say with relative certainty is that if faster than light travel is impossible, if someone were to travel to another galaxy and back, the earth would be a very different place millions of years later. Assuming that it's impossible to return is no more reasonable than to assume that intergalactic travel itself is impossible. 
I reverted some edits to another version of that section, though I don't think that any of them are satisfactory as they are both to some extent unreferenced speculation and there isn't really a whole lot to say without turning to speculation. 51.175.169.128 (talk) 21:22, 20 August 2016 (UTC)
thread_title:  One-way trip