119 réponses à ce sujet

[Skarwael]

wolf99000 wrote...

I know that they think wrapping space might work but we are way off being able to do it

Working on it atm in my shed outside. Will give you guys an update later.

[Inquisitor Recon]

Gladiador2 wrote...
Humanity will rot in Earth. Period.

We even lack the technology to regurarly travel thought our own solar system (and it doesn't matter anyway, as there aren't garden worlds here apart from the Earth). We'll never have the tech required to travel around our nebula for sure, and much less to travel around the Milky Way. At most we could colonize the Moon, Mars, and a few Jupiter moons, and the latter option is already extremely improbable. Again, it doesn't matter, because nearly all the resources would need to come from Earth anyway.

I've the theory that maybe if religions wouldn't have existed (they've been a BIG slowdown in science), and humanity wouldn't have been so stupidly selfish, then maybe by now we'd have at least regular travel thought our solar system, a few viable colonies, and Helium-3 engines. And with such a good base, we would still be in trouble.

The only *REALISTIC* chance we have is that any other sapient species find us and teach us how to space-travel, much like the hanar did to the drells. If not, we'll end like them. And it's highly improbable, too

"Engines of war have long since reached their limits, and I see no further hope of any improvement in the art."
-Frontinus, 90 AD
And there are similar quotes for just about every field of technological development.

Your idea that we've reached a technological dead end is  baseless, as is your view that no other planets in this solar system possess metals and other valuable resources. Your own statement that we will "rot" on each echos so many other (insert idea) is impossible claims. Religion has been a big slowdown in science? The old "blame religion" argument is unsound and ignores all of the politics and countless other reasons we kill each other and will continue to do so. Yes some people would like to blame the Vatican for everything but the truth is far more complex.

Judging from your comments on selfishness

I presume this utopian society you imagine is some sort of pure socialist or communist system, everybody is some godless drone, and people never do what is in their own best interests. Seems far more unlikely than us getting into space by the same motives which have driven technological development thus far.

[TheUnusualSuspect]

adam_grif wrote...
Once it docks with A, it has to match speed and velocity, and now shares a frame of reference. Now going at normal speed everything has renormalized, and ~7 seconds has elapsed since it left from B. Time dilation shifts your frame's perception of time, but doesn't allow you to beat the clock and get there before you left. The amount of time that passed between when you left and when you got there @ ~lightspeed is the exact amount of time it would have taken for a beam of light to get there according to an observer at the launch point or destination.

Aha, which if true then creates this question/statement with respect to the FTL scenario:

If we replace our insta-bullet, with a merely FTL bullet that arrives just as A's clock ticks over to 8 secs, then there's no paradox, correct?  The bullet could, by that reasoning, still be able to travel at such a speed that it takes 4 of A's seconds to reach A from B and causality is thereby preserved.

ie.  FTL travel should still be possible up to the speed at which the paradox would start to occur, no?  Our peak FTL speed is limited by the speed beyond which a paradox would occur, or alternately, from our (B's) frame of reference, even if we fire an insta-bullet, we would not ever perceive it to travel faster than the paradox-limit speed.  The bullet would still hit A at A-time of 8 secs.  From a "static" observer's point of view, the bullet instantly hits A when it's fired from B, and A registers that the bullet hits at Atime=8.  In that respect, travelling at relativistic speeds merely alters one's perception of an FTL event, but not invalidate it?

Modifié par TheUnusualSuspect, 01 mars 2010 - 03:05 .

[Lmaoboat]

adam_grif wrote...

Vaenier wrote...



Best way to get around paradoxes is wormholes. You never exceed the speed of light, you just make the trip alot shorter instead

It's not having a velocity faster than C that causes the paradoxes, it's beating light there in a race that causes the problems. The actual method is irrelevant. Wormholes and Warp drives (which move space instead of the person in the space) both still give it hard in the ass to Causality.

Wait, so how does beating light in a race cause problems unless time itself propagates at the speed of light, otherwise wouldn't you merely have the illusion of going back in time?

[adam_grif]

Consider that the speed beyond which a paradox occurs is based on distance from target and time dilation factor, and is thus not constant. So sometimes firing something at a certain FTL velocity will be fine, but sometimes it will not. Firing it at any FTL speed could potentially result in a time paradox, although they won't always. For this reason, it seems logical to conclude that there will be safeguards against any FTL velocities being achieved, as opposed to universal safeguards that sometimes let you travel at certain speeds but sometimes don't.

[Lmaoboat]

adam_grif wrote...

Consider that the speed beyond which a paradox occurs is based on distance from target and time dilation factor, and is thus not constant. So sometimes firing something at a certain FTL velocity will be fine, but sometimes it will not. Firing it at any FTL speed could potentially result in a time paradox, although they won't always. For this reason, it seems logical to conclude that there will be safeguards against any FTL velocities being achieved, as opposed to universal safeguards that sometimes let you travel at certain speeds but sometimes don't.

What would the difference be between you traveling through a wormhole to somewhere 20 light years away, and simply you disappearing, and an exact copy being created the same distance?  Is something 20 lightyears away actually 20 years in the past?

Modifié par Lmaoboat, 01 mars 2010 - 03:24 .

[redhead1979]

adam_grif wrote...

Lmaoboat wrote...

adam_grif wrote...

you also have to explain why FTL isn't going to result in unresolvable time paradoxes simply by virtue of running thanks to the failure of simultaneity at a distance.

Err, could you put that in layman's terms?

I'll do my best.

Discovering that the Earth was round meant that the direction "up" was relative to the observer - it was nolonger the fixed constant that everybody thought it was. Where "up" is depends on where you're standing on Earth. Relativity indicates that, much like "up", "now" is depending on where you are and how fast you're travelling. This seems very strange, but it can be demonstrated in experiments. Because of this, two distant events can never be said to have occured at the same time. Hence it is known as the failure of simultineity at a distance.

Relativity also predicts an effect called relativistic time dilation (which has likewise been shown to exist in reality), where depending on how fast you're going, time passes at different rates compared to other people. The speed-of-light enforces the sequence of cause-and-effect with all of these factors in play together.

A simple explanation for how time dilation works is the following:

Two spaceships, A and B are moving apart from each other at 0.866 times the speed of light. This is chosen for convenience' sake. It reults in a time dilation factor of two, which means that the from A's perspective, B's clock is ticking at half speed and vice versa. The important thing is that nobody's perspective is "more correct" than everybody elses. This is phrased as "there are no privelidged frames of reference" in the scientific community. If there are, then relativity doesn't make any sense. It's critical that you remember this.


Now to explain why FTL creates a big problem for this:

Suppose instantaneous guns (to make calculations simpler). Their projectile travels in a straight line and at infinite velocity until it strikes something. Ship's A and B have met in the middle, turned and started moving away from each other at 0.866 C. They agree to count off 8 seconds, then turn and fire at each other.

So from A's perspective, it turns around and fires when the count hit's zero. But from his perspective, B is only at 4 seconds! So it strikes B, who has only counted 4 seconds, gets hit by a non-fatal blow. Furious that A has fired before his time is up, he turns and fires at second 4, but by second 4 from his perspective, A is only at second 6. The bolt fires and destroys ship A, only 2 seconds after his count-down had begun, a full six seconds before he fired his original shot.

This is a classic grandfather paradox. Wormholes, warp drives, hyperspace, whatever, it all results in the same thing. To make matters worse, if you calculate from B's perspective initially instead of from A, the exact opposite happens. So not only do we have a grandfather paradox, we have 2 contradictory causal series of events that both should have happened but are mutually exclusive.

That is the single greatest, simplest to understand description of relativity I have ever heard.  Thanks for that!

[adam_grif]

That post wasn't directed at you, it was at the one above you.



The exact same "tachyon pistol duel" situation comes to bear if you use wormholes to fire at each other instead of an actually FTL thing.

and simply you disappearing, and an exact copy being created the same distance.

That would result in the exact same problems, because information has propagated faster than C, which is the root cause of the issue here.

[Lmaoboat]

adam_grif wrote...

That post wasn't directed at you, it was at the one above you.

The exact same "tachyon pistol duel" situation comes to bear if you use wormholes to fire at each other instead of an actually FTL thing.

and simply you disappearing, and an exact copy being created the same distance.

That would result in the exact same problems, because information has propagated faster than C, which is the root cause of the issue here.

Well let's say that the technology exists to create a "short cut" to somewher 20 light year away. You don't actually move at light speed, wouldn't time be moving at normal speeds?

[TheUnusualSuspect]

Lmaoboat wrote...

What would the difference be between you traveling through a wormhole to somewhere 20 light years away, and simply you disappearing, and an exact copy being created the same distance?  Is something 20 lightyears away actually 20 years in the past?

That ties in with my question about how time can be BOTH A=4/B=8, and A=8/B=4 simultaneously.  Such is only true from the observer's frame of reference.  To an inertial middle observer, the clocks of A & B are never out of synchronisation.  The moment a bullet is fired though, you're outside the observer's frame of reference and in the bullet's frame of reference, and in that case, an insta-bullet should logically arrive at time A=8 (B=4), regardless of it being at time A=4 when it left B.

I guess I'm just a bit thick....

[adam_grif]

There are no "normal speeds", but I know that you just meant a speed at which the time dilation factor rounds to unity, so on with it:

Although you might be moving at such a speed through the wormhole, somebody, somewhere in the universe isn't, and so that frame will not see the same sequence as people moving at low speeds. Keep in mind that "frame" doesn't just equal "person in spaceship / on Earth", it could also be a single molecule of hydrogen zipping around at a high speed somewhere.

Every frame must agree with every other frame on the events that occurred (although sometimes due to light lag it might appear that effects happened before their cause). Otherwise some frames are "Privileged", and that no frames are privelidged is one of the central ideas in relativity. Although it might be attractive to say "well, lets just throw out relativity then", it isn't that simple. Obviously, it's doing something right since the now-well-defined relativistic phenomena that we now know all about in the real world were predicted by Relativity.

Modifié par adam_grif, 01 mars 2010 - 03:55 .

[adam_grif]

Well, I'm now officially way above my pay grade in physics terms.



You people should go and ask your local physics professors.

[wolf99000]

I passed that level about 3 pages back adam lol so I am right in thinking if we can go ftl we can also time travel or am I missing the point

[adam_grif]

wolf99000 wrote...

I passed that level about 3 pages back adam lol so I am right in thinking if we can go ftl we can also time travel or am I missing the point

Maybe not in the classical, "lets go back to 1982" sense, but yes, FTL and time travel are functionally equivelant under relativity.

[MajorStranger]

Actually, Element Zero (or Dark Energy) is a theoretical explanation to the universe's expansion. No one has ever been able to quantify his power, or prove his existence, but remember not so long ago people were called crazy for talking about going into space. Who knows if we could actually use this unknown force of the universe for energy use and even if it really exist. But at least Mass Effect's technologie is a lot more plausible than soft sci-fi like Stargate, Star Wars and Star Trek (and for once a game in space isn't named with a Star in his name!)

[AdamBoozer]

Rodriguer2000 wrote...

 seems crazy but its the only way i see us traveling to distant planets lol real life mass relays

We don't even know if ezzo exist. Many of you have know clue what ezzo is lol. element zero also called netronium is matter made up entirely of netrons. some scientist think they are in neutron stars.

But know that that techknology is so far beyond us that we don't really even know where to put it on a practical time line.
As it stands. Chemical based energy like fosil fuels, NOW green energy such as solar and wind, SOON fusion power, LATER anti protons, MUCH LATER anti matter (like star trek), then who knows? anti gravity google Dr Ning Li anti gravity. Kinda makes you wonder about this game actually.

For more reading into the subject check out wikipedia but make sure you check there sources to make sure it's legit.
http://en.wikipedia....ster-than-light

Modifié par AdamBoozer, 01 mars 2010 - 04:05 .

[Lmaoboat]

adam_grif wrote...



Although you might be moving at such a speed through the wormhole, somebody, somewhere in the universe isn't, and so that frame will not see the same sequence as people moving at low speeds. Keep in mind that "frame" doesn't just equal "person in spaceship / on Earth", it could also be a single molecule of hydrogen zipping around at a high speed somewhere.

I don't get this part. How does you moving at normal speeds through the wormhole affect "Somebody, somewhere in the universe"? If you're looking at someone both 20 LY away and right near you through the wormhole, what the difference between that and looking at someone right next to you and at a mirror 10 LY away? If you make a wormhole to a distant star, wouldn't you just be effectively moving that star closer to you?

[JMKnave]

These are all very nice theories. But even though we cannot easily travel to other galaxies at the moment, it does not preclude the human race from doing so in the future. Whether that is through FTL or some other form of travel though is another matter entirely.

It was widely believed at one time that the earth was flat. Until Magellan circumnavigated the globe.

It was also widely believed at one time that the sun revolved around the earth. Until Copernicus.

Right now it is widely believed that we can never attain FTL speeds. Until someone comes along in the future and finds away around all the problems.

Our sun will eventually die like all other stars. So if the human race is to survive, we will eventually have to leave earth and find another planet to inhabit. And unless our future selves wish to die a horrible, flaming death when the sun enters the red giant phase... they better get cracking. I have faith though because necessity is the mother of invention. [Plato]

Modifié par JMKnave, 01 mars 2010 - 04:07 .

[AdamBoozer]

I completly forgot to add in hyperspace it would of been between anti protons and anti matter.

[SpatFieya]

It's all about the dark energy my friends. If we find a way to capture it, manipulate it, create it. Actually, any of those, then the future of ME could be possible. Don't get Dark Matter confused with Dark Energy though. Maybe there is technology on Mars. Maybe. But sadly, we all might be dead and gone before we see FTL travel being applied, maybe discovered, but not sure about it being physically applied (IE space craft). Governments are too concerned who's going to blow the other up and all that nonsense.

It's sad, but it is more than probable.

BUT, that's just assuming. Maybe we'll get visited by other beings, maybe there is a big ass citadel in the sky.. but I wouldn't get your hopes up. Just like in mass effect, we'll probably have to GO and FIND these intelligent life forms.

Maybe other species know we're already here. Either they plan on getting to us, or they want us to PROVE that we can achieve space travel and such on our own. But if they are anything like us, they just want to meet other life forms. To carry a conversation and just discuss about each other.

If there where mass relays, we probably would of seen them, or some sort of proof that they existed. We have already found and have the ability to create anti-matter, we just can't make enough yet to make it a viable energy source.

Technology is booming right now. We might figure out FTL travel on our own before any life discovers us and shows us how. Which is the way it should be. If we discover other advanced life, we would want SOME sort of equal playing field.

Modifié par SpatFieya, 01 mars 2010 - 04:17 .

[AdamBoozer]

JMKnave wrote...

These are all very nice theories. But even though we cannot easily travel to other galaxies at the moment, it does not preclude the human race from doing so in the future. Whether that is through FTL or some other form of travel though is another matter entirely.

It was widely believed at one time that the earth was flat. Until Magellan circumnavigated the globe.

It was also widely believed at one time that the sun revolved around the earth. Until Copernicus.

Right now it is widely believed that we can never attain FTL speeds. Until someone comes along in the future and finds away around all the problems.

Our sun will eventually die like all other stars. So if the human race is to survive, we will eventually have to leave earth and find another planet to inhabit. And unless our future selves wish to die a horrible, flaming death when the sun enters the red giant phase... they better get cracking. I have faith though because necessity is the mother of invention. [Plato]

WOW other galaxies? slow up there that's REALLY advanced. FTL can't even accomplish that at fast speeds. You have to realize that the universe is a MASSIVE place. That is maybe a thousand years of development and scientifc progress with no interuptions. I just hope I live long enough to to see commercial space flight really.

Mangellan died when he got invloved in a war in the pacfic his crew finished the expedition lol. Sad tell.

Don't even get me started on copernicus (sp?)

I wouldn't say widely bealived only among the un educated masses who bealive what ever the media says. We know the ways to do it but it is taking us time perfecting them because there are literally many ways.

In millions of years it will die yes. It will be long before our sun dies when we need to leave. Don't forget this place has had many mass extentions (ironic that ME mass effect sounds like ME mass extintion) . I wouldn't say it is horible you wouldn't feel a thing from that.

Right now we are in a technilogical revolution accomplishing what use to take thousands of years in 10 years or less.

[SpatFieya]

JMKnave wrote...

These are all very nice theories. But even though we cannot easily travel to other galaxies at the moment, it does not preclude the human race from doing so in the future. Whether that is through FTL or some other form of travel though is another matter entirely.

I agree, but I wouldn't even worry about traveling to other galaxies. You want to ride your bike around the block a couple times before going out of the neighboorhood..

love the plato quote btw.

[AdamBoozer]

So many people get dark energy confused with element zero. I don't get how. There have been several games and shows that have had this. Check it out here if you want to know more.



http://en.wikipedia....wiki/Neutronium

[WoodWizzard87]

What would be the point of colonizing the moon or Mars? there is nothing there, so we'd rather just spend billions of dollars to send someone there just to explore it. If we were to colonize the moon or Mars, it would be the most non-economical thing to do. Yeah we'd get rid of a few hundred thousand people, but the costs to ship them there and set up camps big enough to hold them all would be astronomical.



Theres all this talk about FTL drives and reaching the speed of light, which as of now and probably the next 1000 years will not be possible. I know you physics majors in here most likely know that the cost of fuel to get a ship up to the speed of light is rediculous.



How about slowing the ship down at the destination? You get to the latest star and coming at the speed of light, how much energy and fuel would you need to slow that ship down again to orbit that sun. Unimaginable amount to speed up and slow down.

[TheUnusualSuspect]

Reading through Wikipedia (have been for a while). I guess it comes down to this. General Relativity predicts the possibility of both Albucuirre (Warp) Drives, and Wormholes. General Relativity does not specifically demand the principle of causality, but the principle of causality is assumed to be absolute (ie. there can be no such thing as paradoxes). What is not yet defined is the relationship between causality and relativity. I guess that's about where I started to get hung up on the simultaneous A=4/B=8 and A=8/B=4 thing. General Relativity predicts that to be true, simultaneously, within each observer's frame of reference, but that can create a paradox in and of itself even with non-FTL bullet launches (B launches at time 8, which is A's time 4, so instead A sees the bullet launched at B's time 2, which is false), so to me either the principle of causality is right, or relativity is right, or we don't yet fully understand the relationship between the two, and FTL is still possible, just that some people are applying the principles of causality incorrectly to general relativity. In my perception, an insta-bullet leaving at time=8 on B's clock, would arrive at time=8 on A's clock, and that would then satisfy both causality and relativity.

I guess the question remains as to whether that can be proven mathematically, and that is WAY beyond my skill set.

Modifié par TheUnusualSuspect, 01 mars 2010 - 04:26 .