143

A guy named Arioch has a webcomic called Outsider (highly recommended, BTW) with a simple and elegant solution to this problem. Ships in that universe use a drive that jumps them through hyperspace, but the drive only provides the initial impulse to break the ship out of the plane of normal space; the hyperspace trajectory afterwards is purely ballistic. By ...


105

But in most stories, FTL doesn't actually follow Newton's 1st law; everybody knows that once your hyperdrive fails, you're dead in the water. Otherwise, the Enterprise could hit warp 9.9 and easily coast across the galaxy. And that actually makes sense in the warp-style of FTL: FTL travel is only possible within the field generated by a functioning FTL ...


79

Use real world examples? Criminals could 'run away' to the Americas or wherever in the 1600s. In that case, how would the Spanish crown capture them? What about outlaws that fled to the territories in the 1870's United States? Or Russians that escaped to Siberia in the 18th century? First off, this is exactly how pirates came about. If you have people ...


78

1000 times the speed of light means you can visit something 500 lightyears away in a one-year round trip. 5000 lightyears would take a decade and you are still not even leaving our galaxy. In contrast some things that can be observed with telescopes are millions or even billions of light years away. So astronomy would still need telescopes! [Edit, added ...


75

As you said, any FTL drive is implicitly a time machine. Let’s review the reasons why. As a prerequisite you need to understand spacetime and the ideas of space-like and time-like intervals. first you need… We will make use of space—time diagrams which show that events (points in spacetime) have different x and t values depending on your reference frame. ...


71

1. Space is mostly empty If you pull the trigger on this, you're ruining someone's day, somewhere and sometime Well, not necessarily. There's so much empty space between anything interesting in the universe, that it's very likely that those "shots from a cosmic shotgun" will just keep traveling through the cosmic void, never even approaching anything ...


68

I would think so. Innovation is probably the hardest bit and duplication is much easier. We see it with computers all the time now. Some small company comes up with a new idea that is "obvious" and then suddenly everyone else can duplicate it. The same is with other STEM fields, the knowledge that it exists (and ideally something to experiment with) helps ...


64

It depends on how far from the current production possibilities frontier this technology is. There are several possibilities, depending on the technology gap: It is like the Apollo Moon mission to Stone Age hunter-gatherers. We (the hunter gatherers) can probably recover some debris, use it to bash stones or store berries, but we have neither the industrial ...


61

It is impossible for the ship to travel at the speed of light, it can at best travel close to the speed of light. The difference matters. There is nothing really stopping two ships travelling at a speed arbitrarily close to c from communicating with lasers or radio. It will take the laser the same time to travel the distance as it would if you travelled at ...


54

It is common to require that FTL only operate at some distance from large mass. So, the ship must withdraw (say) beyond the orbit of Neptune before engaging. Likewise, ships will arrive at this distance. In some of my other posts I also mention the idea of needing to match velocity with the special preferred reference frame. This would require months of ...


51

The traditional answer to this question is "FTL drives don't work within gravity wells", which is sometimes justified by saying that they require a region of "flat" spacetime to operate reliably. If you're within a gravity well (i.e., spacetime is significantly perturbed), then they become dangerously unreliable and can self-destruct, shoot you off in ...


50

This is a fascinating question that will have a substantial impact on your story. I love it! Let's get some basic observations out of the way, which will include some restatement of your limitations. A group of individual ships launching in tandem always arrive at the same time, but within a +/- 10% variance of when they expected to arrive. Groups of ...


47

Impossible to answer. I'm using the answer format rather than a comment to get enough space to explain. FTL travel will probably require a paradigm shift in science. The necessary theoretical hints may or may not be observable. Imagine somebody like James Watt gets a tour of a nuclear power plant, but without a helpful tour guide. He might have recognized ...


42

Make the aiming difficult If the lowest precision of coordinates you can aim at still has an error margin greater than the typical size of a solar system your method would not be usable for travelling distances shorter than said margin. Example: Aiming at the sun would result in arriving anywhere between the Sun and the Kuiper Belt (some ~50 AU error-...


38

So the elephant in the room is the halting problem. Consider a program like this: while (true) { } // do nothing forever cout << "Finished" << endl; This can never halt. It can never print "Finished." Clearly it cannot complete nearly instantaneously. So the solution has to handle this infinite case. Your solution is to have the machine ...


38

Is there a theoretical method of inferring a "universal" time that FTL travellers can use for their clocks to maintain a constant time? Generally, no. There is no universal time, period. Relativity tells us that it is impossible to put a time ordering relationship between spacetime events that are not in their respective light cones, or in other words, ...


36

I think you've got yourself in a bit of a corner. Without FTL, trading would be nomadic rather than what we think of today - think the old Silk Road, or traveling peddlers. It'll be people whose livelihood involves being constantly on the move, buying stuff here hoping it'll sell for more than that on the other end. (This of course assumes that we don't ...


33

This is well addressed by this excellent site for sci-fi writers. Turns out, you're doomed: For example, the most expensive substance on Earth is antimatter, which currently has to be manufactured atom by atom at a cost of $100 trillion/gram. Let's say we can make it for 1,000x cheaper and that the friendly aliens at Proxima Centauri are desperately in ...


33

This is actually very interesting Mathematically (mathematics here means computer science, and computer science is NOT programming - it's a branch of pure, not applied, mathematics). NOT the Halting Problem First, let's get something out of the way - the halting problem. Most of the answers here give a wrong description of the halting problem. The halting ...


32

TL;DR: "Scientifically correct" (according to current established science) and "faster-than-light travel" cannot be used in the same context without some form of negation. What you are asking for is not possible within the boundaries of science as we know it. Here's why: Our best model for this type of effects, insofar as I know, is special and general ...


32

Actually, this is a good question. I need to make an assumption: Given that the cost (economic, energy, time, etc.) of colonizing any planet in the galaxy is for all intent and purposes equal, what would be the motivations for colonizing any particular planet? So long as I'm not too far off-base with my assumption, the reasons people colonize vary ...


32

Pulsars Expressed in popular science terms: pulsars are our natural galactic GPS system. Pulsars are how the Voyager records leave a map back to the Solar system for anyone that finds them. The pulsar map is on the lower left Pulsars are really easy to detect and get a bearing on. You say that wherever you end up will be at least roughly mapped. I am ...


31

Contrary to the OP’s concern at the start, this is not a dumb question; it is actually a very good one. Most of the answers this post has received are pretty much wrong, and in this group that means that you must have asked a question that relies on a bunch of really technical underpinnings. So kudos! The Common Mistake The common mistake among answers ...


30

Okay so this is the best image I can find of where we actually are in the galaxy: If most of the life in our galaxy evolved in the core and spread to the two "main" arms of the spiral (the Scutum-Centaurus and the Perseus) then there wouldn't be a lot of point looking at the relatively few stars of the Orion Spur where we have evolved. In fact to a species-...


29

This is one of the best explanations that I've ever read, courtesy of Wikipedia. It deals with FTL communication rather than strictly teleportation but the principle is the same. Numerical example with two-way [faster-than-light] communication As an example, imagine that Alice and Bob are aboard spaceships moving inertially with a relative speed of ...


29

First off, there is no realistic way to limit an FTL drive because there is no such thing as a realistic FTL drive in the first place. That is to say, any drive that allows you to physically move faster than light is not only impossible but nonsensical. This is due to a few reasons such as time dilation (time would stop for you), space contraction (you'd go ...


29

Stars don't simply change their orbit. Most stars will be in an orbit around the galaxy's center of gravity. This orbit might be disturbed by other masses, but the disturbance will only happen very, very slowly. That's much like the problem of flying to a planet in the solar system, or sending a tight-beam radio transmission there. You need good data about ...


28

During World War 2, suddenly someone had a nuke and without question demonstrated it was possible to create that device. Where before places and nations only had theories, now they had proof, and within a relatively short period of time other places created their own nuclear devices. Comparing nukes to FTL is an incorrect analogy, and examining why will ...


27

I don't think your setup will actually result in the two sides fighting using lesser weapons, it just doesn't make sense. If the enmity between them is so great that losing multiple entire systems doesn't make them reconsider fighting, they aren't going to put on the kid gloves now. I see a couple of way this war could go. "Strike fast. Strike hard." -...


27

Almost all of the answers are about theoretical problems with the infinitely fast computer. I see it like this: The machine is an oracle, which reads the source-code and tells you what the solution is. This won't immediately help with most problems, because most real-world interesting problems operate on huge amounts of data. Someone said the nation with ...


Only top voted, non community-wiki answers of a minimum length are eligible