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@StupidAndy Just because some of these resonated with my time at school in some way, probably mostly because they are all so normal: I get in trouble for defending my friends and myself from racism and other things Thats the unfairness of life for you. I'm just as good and probably better then 95% of the people in my grade, but whenever I do anything I'm told "OMG SHUT UP" YOUR SO *explicative* ANNOYING!!" "GO AWAY YOU *explicative* Thats what being a standard geek was like in the early 90's as a matter of routine. my English teacher asks for a 12 page story of a quarterly workshop piece (yes, its stupid) and she gives us only two weeks and no days to work on It, and she only reads the FIRST PAGE] Ha! This is the same in every school. I get in trouble in French because I know nothing about it School? Amirite? people think that they are the only people whos opinions matter, so the second that someone says something that completely is the opposite of what they believe they go up to the teacher that they "are disrespecting my opinions" when I never said anything to them Welcome to life. The trick is finding someone worth voicing your opinion to, with some people, its not worth your effort. Telling these groups apart is non-trivial. shipping, I need to say no more, its stupid Shipping? Or shopping? Because if its the latter, I am on board with this sentiment. people think that kerbal is "launching little green "*explicative*s into space then killing them And some people think we didn't go to the moon, dont dwell on it. they think kerbal is warmongering and, what's a stupid game?... call of duty is peaceful they all think that the world. is. flat. they think any person who isn't exactly like them is an idiot, they also think that anyone like them are copycats they also don't believe in evolution because they don't want to be related to animals There are 7 bilion people in this world, most of them are like this, or in some similar way. Identify people who are not, dont pay attention to the others. DONT get militant about the existence of the others, there are better/more important things to worry about. there's a certain someone in my grade, who does everything as a joke, and everyone believes him Wouldn't be school without a guy like that. they think that the space program is a stupid waste of money Honestly, I could have a very serious conversation about that. If you treat the ideas with respect, you can discuss any topic. And, uhmmm, yeah the Hitchhiker's "42" bit was mostly your fault, but Im getting that you know that already lol!

That's it, man. Game over, man. Game over. RIP

A good mathematical model will spit out garbage if you enter impossible conditions, I doubt there is an explanation anywhere! Even the folks in the papers that describe what bewing was talking about (FTL in quantum tunelling) noted that a zero-time event "has no physical reality", because zero-time implies infinite enery (and probably lots more complex science and maths to that effect.) Hence their paper whilst interesting and apparently high-quality, does not disprove Special Relativity in one fell swoop.

No malice, but I feel 100% confident in telling you that you may have interpreted something incorrectly. No-FTL is one of the hardest-standing laws in the physical world. Note that it is possible for a wave to have a phase or group velocity above c, but there is nothing actually travelling above c. It is analogous to how a shadow could be made to move across a surface above c. There are also caveats that can be made with the expansion of space itself, but again, there is nothing that is moving locally faster than c. I've never heard of alpha decay violating FTL, in fact they are known for being particularly slow. I'd love to see a source for that. Ah no, wait, its probably related to quantum tunelling and how the particle escapes the nucleus, see below. In the quantum physics world, things get weird ok. But even with "spooky action at a distance" there has yet to be any sign of even information (lat alone some matter) being transmitted FTL. Einstein might not have liked the idea, but that doesn't mean that special relativity goes out the window. Special Relativity is one of the most sturdy, supported, observed theories in the scientific world. I cannot state that highly enough. The Heisenberg uncertainty principle is another source of confusion for many - when you dont know exactly where a particle, and then you suddenly find it somewhere unexpected, it can appear to have moved fast, but again, there has yet to be any known mechanism for moving mass FTL. As for quantum tunneling, there have been some weird results, but whether or not something was actually travelling FTL is still highly spurious at this time. It has definitely been found, for example, that there is no causality violation, and another team found no violation of special relativity at all (something to do with very complicated particle physics that goes over my head). Clearly what exactly is happening during quantum tunneling processes is not yet 100% understood, but that is a far far cray from "a bit head-in-the-sandish". 1 intriguing journal paper does not an overturning of special relativity make, same goes for any other physical concept. If anything, treating single results with such importance is putting your head in the sand. Im open to the idea of the FTL barrier being broken in a significant way, if that is the way it turns out, but we are far from that point. Not everything is possible, after all. At this point, "No-FTL is one of the hardest-standing laws in the physical world." is one of the safest statements that you can make. There is definitely a lot of interesting and weird stuff going on in the quantum world these days, but we are not at FTL yet *** It is neither mass nor momentum. Both of those are classical concepts. Relativistic-mass has been stated to be the increasing property, though this term has its problems. It is probably safest, and most correct, to say that "Energy increases without bound as v->c". *** Edited that last part a few times, think Im pretty happy with it now.

lol really I was just covering my back in case someone has a much better idea lolol

Two of my favorite mods, as long as they play nicely together, use both.

I thiiiink that at 1.0c, (if the universe didn't implode) the trip would appear to take exactly 40 years for an outside observer. For the traveller, the time it takes is not instant for time still flows normally within the ship from the PoV of the traveler, but the "time it takes" is meaningless because the traveler observes time to have stopped outside his ship. Time within and without the ship is completely independent, I think. ** Of course all of that is wrong because its impossible, we are literally talking about something outside the rules. It would be just as correct to say that everything turns into chocolate at 1.0c, the laws of physics like that idea about the same.

I think the answer was reached pretty quickly. After that we, or I anyway, just started thinking about all the other interesting stuff that goes with it.

lol I know I know, I just got carried away with calculators! Relativistic mass is not used often, but it does quite graphically illustrate that something weird is going on.

@KerikBalm @Green Baron To travel 40ly @0.99c, the traveller experiences: For an observer moving with the object the travel last 5 years(s) 234 day(s) 14 hour(s) 10.341897338629 second(s) To travel 40ly @0.999c, the traveller experiences: For an observer moving with the object the travel last 1 years(s) 287 day(s) 18 hour(s) 26 minute(s) 46.699442148209 second(s) To travel 40ly @0.9999c, the traveller experiences: For an observer moving with the object the travel last 206 day(s) 11 hour(s) 16 minute(s) 49.569235172123 second(s) ...0.99999c: For an observer moving with the object the travel last 65 day(s) 7 hour(s) 1 minute(s) 57.075729092583 second(s) Calculator breaks at 0.999999c http://www.dcode.fr/time-dilation for Relativistic mass-energy (basically kinetic energy corrected for relativistic effects): A 1ton mass travelling at 0.99c: 6.6*1014 MJ A 1ton mass travelling at 0.999c: 3.6*1015 MJ http://keisan.casio.com/exec/system/1224060366 And I couldn't find a calculator that didn't give "NaN" for 0.9999 and above What that shows is that to accelerate 1ton from 0.99c to 0.999c requires 2940 trillion MegaJoules! Which is what stops you from reaching c (imagine what the numbers would be if you add a few more 9's) Thats relativity for ya! **edit** Oooh more online calculators! At 0.99c, your 1ton mass has a relativistic mass of 7.08tons. At 0.999c ... 22.3tons At 0.9999c ... 70.7tons At 0.99999c ... 220.6tons http://www.ultimate-theory.com/en/2012/12/26/special-relativity-mass-calculator This mass increase (which is a real, measurable increase in mass, although it is different to "real" or "rest" mass) only partially explains the huge energies associated with high relativistic travel, there are also weirder effects caused by time dilation and length contraction.

Quoting myself - narcissistic? Daydreaming about this concept - What does a mass that collapses into a black hole whilst travelling backwards in time look like? Well it looks like a black hole that explodes. What does an exploding black hole look like? It looks like a large splash of hard radiation [probably]. And look at that, everything that was massive in your body is now travelling at 1.0c! If you put enough EM energy into a small enough space, part of it can convert to mass. You need two photons, without 2 object there can be no interaction and no effect (or some really complex maths that says roughly that) 2 very high energy photons can interact to produce a spray of massive particles and a single (or multiple?) lower energy photon(s). So light with enough energy can convert to mass. In our thought experiment we have a mass exceeding the speed of light and converting to EM radiation ("light"), which is the same as the physical example above but backwards in time! A meaningless thought experiment, but what the hey Your calculations are slightly askew: 283.5 years is how much time a stationary observer would experience if you specify 40 years of "ship time" if travelling at 0.99c. I think. So if you're on a ship travelling 0.99c and count off 40 years on your clock, when you stop, 283.5 years will have passed. And you will have traveled 0.99*283.5 light years.

RealTalkTM? Nobody knows. Mainly because theory forbids this from happening to anything with mass. Its like asking "What happens if you divide a large prime number by 3 and get an integer?" nobody knows because none of the rules that we know to work make any sense under these conditions. There are no mathematical models that describe a large prime that is divisible by 3. Extrapolating from well known theory (skipping past the parts of the theory that says this is impossible) says things like you travel backwards in time, or collapse into a singularity as your mass goes to infinity, things like this. Infinites come up quite a lot in the maths which describes our physical theories, but they are generally accepted not to be 100% literal. It is perfectly acceptable for a mathematical model not to work under extreme conditions, and maths spitting out infinites is a good sign that this is what is happening. Eg: the singularity at the centre of a black hole is described as being infinitely small and infinitely dense. It is assumed that in reality, it is "merely" extremely small and extremely dense. So when theory tells us that you would become a black hole shooting back in time, that might not be literally true in reality. That might make a good sig If you dont ignore the parts of theory that forbids this, the answer becomes: as you put more kinetic energy into an object, it approaches 1c asymptotically. As in, you get closer and closer but every joule of kinetic energy you add gives less and less raw velocity. Even if you poured the entire energy of the universe's rest-mass into your kinetic energy, all you get is closer to 1c, you never reach it. Your relativistic mass (which is real and measureable, although not quite the same as regular mass) also asymptotes to infinity, but of course never reaches it. It is concievable within physical law, to accelerate a grain of sand so fast that its mass become so great that if it passed through our system it could tear it apart. Whether there is enough energy in the universe to get something that fast is another question, but it is allowed. Going faster than 1c, or reaching it at all, is not. At least as far as we know. (Which is quite far actually, but we are scientists and rarely deal in absolutes)

I think its fine. Its just that most interpretations resemble a classic "anti gravity" drive, which is fine for sci-fi, but not exactly that new or exciting. Discussing more dramatic circumstances is more stimulating Thinking of unusual situations is great for sci-fi, but your idea might need a bit of tweaking to avoid massive-earth-death. Also, the effects of turning off gravity would be so far reaching that it would take a lot of the book just to describe it properly. In terms of the story, it might be worth thinking of limiting, or "modulating" the scenario a little so that your dramatic elements are not overshadowed by what the reader imagines is happening elsewhere. OR Go full-hog, turn off earth gravity for a significant time and base the book on what happens. From the ALSEP wiki page: "The ALSEP system and instruments were controlled by commands from Earth. The stations ran from deployment until they were turned off on 30 September 1977 due primarily to budgetary considerations. Additionally, by 1977 the power packs could not run both the transmitter and any other instrument, and the ALSEP control room was needed for the attempt to reactivate Skylab. ALSEP systems are visible in several images taken by the Lunar Reconnaissance Orbiter during its orbits over Apollo landing sites."

Its not you, dont worry *** On another note, mods for KSP come in many many different flavours, with different installation procedures, occasionally involving manual changes to existing files. I dont know the ins-and-outs of how steam workshop works, but I bet that that doesn't help.

It might not be a ship, could just be a rock. Also, people on strategic mass-destruction missions are likely going to be trained very hard to ignore messages from the enemy whilst en-route.

Firstly, due to the rotation of the Earth, everything on the planet not tied down, will fly off into space, at quite a rate. Including the atmosphere which will leave quite a lot faster than everything else. The Moon and oceans would also depart. There would be extreme tectonic events all over the globe as various stresses were released. The Planet would expand slightly, with various effects, possibly including bad things happening to the crust. I hesitate to say that the planet would literally explode, but there is a colossal amount of energy tied up in the gravitational potential of the Earth's mass AND in its rotation, and rock/magma/earth-material is not known for its tensile resilience. If gravity then suddenly "switched back on" the exact reverse would occur, with the Moon being recaptured into a wider, much more eccentric orbit. More extreme tectonics as the Earth re-compressed. Multiple quadrillion tons of dirt, rock, debris, air and water come crashing back, smoothing the surface nicely. It would probably be the end of the world as we know it. The vast majority of people would be killed by various impacts. Most building are not attached well enough to the ground to support their own weight, and if they were, their structures would fail anyway. (they just aren't designed for this) If it just affected the shuttle on its own, then what you would do is retire the shuttle and build a bespoke craft based on this method liftoff (does it have to re-enter normally?). If gravity comes back whilst you are in space, you are going to want enough dV to achive an orbit, but this will be significantly less dV than the current shuttle. *** This makes a better concept for an end-of-the-world or post-apocalytic scenario (I'd read it), rather than a means of space travel (it doesn't really make sense for it just to be switched off for the shuttle, unless you just want to McGuffin-in a standard sci-fi anti-gravity drive, but that has been done to death, and makes space travel less interesting anyway).

Can you fight an interstellar war with a minimum 8 year travel time (for alpha centauri which I assume we are all basing this on)? Theres quite a risk that peace might be achieved whilst your planet killer is still on the way. Or *theirs*. *Why* you would fight such an expensive war with someone so far (in time) removed from your society is a discussion for another thread, but helps to form the assumed technological environment. Even so, cutting warning time in half would still be a highly significant military advantage.

We ARE talking *interstellar* war here... It presumes levels of technology, and economy (possibly more important) that make these things far more plausible. If it takes 3 centuries for your weapons to travel the distance, the war is not really a war is it. High relativistic travel is almost assumed as a given.

Relativistic Kinetic weapons are usually defined as travelling fast enough that it arrives at its target only shortly after any possible observation of its departure via light. Its about the only stealth that works.

Theres a whole thread on here about how "Orion" is a ridiculously popular choice for space project names. I think I even started it. Even this thing is called "Orion":

You think that wont bring sterilising fire?

The only defence against a RKV is to pre-emptively exterminate any civilisation which has the capability to build one. Greg Bears "Anvil of the stars"/"Forge of God" book pair dedals with this concept, although with a slightly different weapon (Von Neumann weapons). As in, as soon as you get word that the folks at Alpha Centauri have the technology to launch an RKV, let alone build one, you launch yours. Its the only way to guarantee survival, boiling it down to an arms race. Downside - your action will be visible for light years, advertising yourself as someone very much worth exterminating (not only do you prove you have RKV capability, you prove you have the will to actually use it). So the other option is civilisational stealth, which as you can imagine, has its problems.

Which should highlight why spaceflight should not be taken lightly. I cant think of a way to take something *more* likely than to make a mobile phone app about it and have some spurious competition. I doubt they will go through with it fully, even just to avoid the inevitable "I won the game but I weigh 49stone so failed boot camp on the first day but I deserve stuff!" lawsuit.

How? Because with my stockpile of fissiles built up before hostilities, I was able to deflect X% of incoming rocks, especially over strategic targets like uranium processing plants. Counter-proposal: If waging war between jovian moons, dont fight from *your moon*, its all about secret bases in the belt, havn't you been watching The Expanse?

There's gotta be some fissiles SOMEwhere on those rocks. If its here, its there.