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[3phemeral]

yeah. this is making it worse... hahaha

You should watch this video. They're simple but effective at explaining the general concepts:

Dr Quantum explains the Double slit experiment, entanglement and flatland.

Be forewarned, though, there's a bit of dramatization concerning descriptions like "it's as if it knows you're watching it." It means more "the act of measurement" and not necessarily an innocuous glance. That said, it is still absolutely insane behavior.

And then onto something like this:

"A Universe From Nothing" - Lawrence Krauss, Richard Dawkins

As Lawrence would say, if you say you understand Quantum Mechanics, then you don't understand it at all. So don't feel bad I'm still absorbing as much as I can on this stuff and every time I re-watch a video, there's a nugget of information I missed from the first few viewings.

You're right. It would be more accurate to say we found the boundaries at which the theories no longer predict correct results. I was referring more to those who at various times in history stated that the current theories must be correct for all conditions and scales... the 'we know how this works and it must always hold true' statements are often proven wrong.

Ah, sorry. I was just worried it would be misconstrued because I've heard similar arguments before and was hoping the thread wouldn't go down that road. Thanks for clarifying

 

[Foolworm]

They're not similar at all actually. The specific argument varies but you'll see things like "they said we'd never break the sound barrier / man would never walk on the moon / we would never fly", but they're all similarly lacking in content. The same arguments can be applied with equal merit (i.e. very little / none) to anything that is thought impossible.

As to why those specific analogies you made are bad comparisons, it's because there was never a fundamental physical principle preventing spaceflight. People did not know the mechanisms by which it could be done, or whether there was something of sufficient power to get it done, but these were all engineering problems. The light speed limit is a theoretical physical limitation. They're not comparable.

On the other hand, our science (and therefore physics) are only as good as the observations we have made. Remember that thus far, our observations are made from a single perspective - Earth. A sample size of one is meaningless.

That is why I am so interested in Voyager and the data it gathers from beyond the solar system. It will be the first direct information that we gather from a deep space location (i.e. unaffected by the Sun's gravity field). I have a feeling that our current physics models are too fine-tuned to the data we currently have.

 

[User 73706]

It's not really FTL travel anymore, but what if we did something along these lines?

-When technology becomes available to do so, create a Quantum Checkpoint. This functions sort of like a time machine, utilizing quantum entanglement to allow us free time travel as early as the creation and powering on of said Quantum Checkpoint.

-Create a Quantum Endpoint. This is a similar time machine that functions as a receiver node. Using the Quantum Checkpoint, scientists travel as close to the end of eternity as possible, and lay down the receiver node.

-Once the Checkpoint and Endpoint are in place, you're essentially allowed unlimited space-time movement just as long as the two don't run out of power (which we'll ignore for the sake of the example). In the event that one of two is destroyed, this timeline is now classified as a Beta Timeline.

-Beta Timelines should be regarded as failures, as the Checkpoint and Endpoint do not exist for eternity.

-There is a lone, paradoxical Alpha Timeline in which the Checkpoint and Endpoint make it all the way through their existences. In the event that the Checkpoint or Endpoint are destroyed in the Alpha, a duplicate is taken from one of the many tainted Beta Timelines to use as a replacement. Precision time-hopping could allow you to "Indiana Jones" the Quantum switch to avoid some sort of mass paradox.

-People in the Alpha Timeline actually use Beta Timelines as conduits, because we know they operate under similar properties as our own timeline. The Beta Timelines could arguably be considered parallel universes, and for safe travel one could simply go from point A to point B at the Beta Timeline's genesis (meaning there wouldn't be enough time for subversion of natural physics) and suspend their bodies (if we still have them) in cryo to emerge at whatever point is desired in the Alpha Timeline.

A contingency plan would be to create the Quantum Checkpoint and turn it on, and create the Quantum Endpoint but leave it off. A group of brave souls would wait with the Quantum Endpoint until the end of existence and turn it on at the last possible second, making it function as a sort of Pre-Alpha Timeline.

Keep in mind I have no idea how to science.

 

[twobear]

Wow! If scientists can "go faster" than the speed of light, would that interfere with any of Einstein's theories? As I recall, many of his equations were based upon the speed of light being absolute and unable to change. Would his current theory remain relevant since these guys are somewhat "nudging" light along to go a little faster? I'm assuming what these scientists are doing can't be found in nature and it wouldn't jumble Albert's equations too much.

No, in fact, this idea is based on Einstein's general theory of relativity.

It will eventually become an engineering problem. As it stands, it's a theoretical problem in that we have to come up with some inkling of a way to overcome the speed of light limit but eventually we have to engineer the thing to make it happen. Theoretical solutions don't come out complete with an engine, you think up a way to possibly do it then someone figures out a way to make that happen.

We don't actually know which is more difficult, it may be actually even more difficult to engineer the means than it is to actually come up with the theory.

I'm not sure why my saying it's orders of magnitude more difficult means that I think we already know the way to achieve this and we just have to make a thingy?

This assumes that everything that is a theoretical problem is an engineering problem waiting to happen. Reality doesn't work that way. It might just be the case that there is no way to travel faster than light.

 

[twobear]

dp

 

[Bear]

Quantum entanglement happens with speed that it as at least the speed of light, possibly instantaneous. But they cannot transmit information.

There is also a similar "violation" in wave theory, where a wave may have a phase velocity greater than the speed of light. Information travels at the group velocity, however, and that limited by the speed of light.

What makes the speed of light limit difficult to grasp is that it doesn't, nor should it, apply to literally everything. Not everything is restricted to the limits of matter or information.

On the other hand, our science (and therefore physics) are only as good as the observations we have made. Remember that thus far, our observations are made from a single perspective - Earth. A sample size of one is meaningless.

Not all physics relies on observation. That is one of the greatest strengths of theoretical physics, you can analyze just about every conceivable condition as long as you can work out the math.

There is plenty of research done about conditions we will probably can't ever observe directly. Off the top of my head, someone in my department is studying the behavior of charged particles around a black hole. Unless we're considering another universe with different laws, our laws of physics should hold anywhere.

 

[Septimius]

Apparently the universe expansion is increasing in speed, so it's faster than the speed of light.

And if you have like a schrodinger's cat situation where one cat has to be alive and one has to be dead, but you don't know until you check one, once you check it, the other collapses into reality faster than the speed of light (because it could be any distance away from you when it collapses into reality).

What?

 

[zoku88]

I never said proven facts, I said reason to believe. The theories are out there so we have reason to believe it could be possible in some form. All of this stuff is way into theoretical territory.

What theories are you talking about? Do you even know?

Tachyons are more or less used to think about what would happen if faster than light travel were possible.

There is no logical reason to believe that they exist. Not only is there no evidence for them, but their existence creates logical paradoxes.

 

[antonz]

The Warp Drive they are working with on the theoretical level does have some flaws if we are able to make it a reality.

The Warp Bubble for instance would trap and hold all the space radiation etc gathered at the front of the bubble and when the Warp Drive would be turned off and the warp bubble dropped it would cause a massive wave of radiation to shoot forward from the vessel.

The radiation would be extremely lethal so it would require very specific navigation etc so we wouldn't irradiate earth for instance or accidentally piss of the romulans.

That said Science fiction for the past 80+ years has been calling for the design that is now deemed as needed to make the drive practical in terms of energy requirements. Funny how that stuff seems to work out in scifi concepts that end up practical

 

[MetatronM]

I think this is an important reminder

You can go north of the north pole. You can go so far north that the compass points south. Ergo, warp drive in the next 10 years!

Take that, science!

 

[Septimius]

I never said proven facts, I said reason to believe. The theories are out there so we have reason to believe it could be possible in some form. All of this stuff is way into theoretical territory.

You know, I've read all your posts in this thread, and they're nothing more than "well, people didn't believe we could fly one day, so I still think it's possible to go faster than light one day." You don't seem to get that we don't think we can't go faster than light, we know why we can't go faster than light.

You continue to wave your hand and show to tachyons, a theoretical object that ALWAYS goes faster than light (different than accelerating to faster than light) along with some other largely inconsistent stuff. It's comes of as an attempt to explain your position to explain why you think it'll one day become possible, when it's clear you have no idea why it's deemed impossible today. The tons of knowledge that constantly undermines this theory, that GPS satellites wouldn't work if it weren't for the theory of relativity, and that alone shows it's impossible to accelerate to the speed of light (if you have mass).

If something someday provably moves faster than the speed of light, your assessments are still way off.

 

[Kenka]

My physics 101 is being tested but its all about the E = mc2 equation.

The faster something moves, the mass increase. If something can go as fast as or faster than the speed of light, it must have infinite mass.

If an object has infinite mass, it means it has infinite energy according to Einstein's law above.

Something with infinite energy cannot exist because it is impossible to have an infinite thrust force (the cause) to give an infinite velocity (the effect) to obtain the infinite energy.

I'm sure Einstein would be laughing at my explanation though.

below link my be clearer:
http://curiosity.discovery.com/question/anything-go-faster-than-light

Uh sorry, I kinda misunderstood your question. Well, please someone correct me if I'm wrong but I think that "the speed of light can't be exceeded" is a conventional thing in our current interpretation of spacetime (Minkowski's spacetime), because, as someone said before, exceeding the speed of light means that the effect happens before the cause, and such thing isn't concievable by the current physics theories

http://curiosity.discovery.com/question/anything-go-faster-than-light

Seems like what they're saying is that after you achieve the speed of light then there is no known energy source that then give you enough thrust to pass the speed of light.

I suppose you could think of it like the days before rocketry where we could see the outside but didn't have anything with enough oomph to push us outside our atmosphere. It's outside the bounds of our relative understanding of the universe to break the atmosphere until we find it. FTL is highly likely the same thing in my opinion but IANAS.

Ooooh, guys you are cute to have replied to my question, thanks :'-(

 

[Foolworm]

Not all physics relies on observation. That is one of the greatest strengths of theoretical physics, you can analyze just about every conceivable condition as long as you can work out the math.

There is plenty of research done about conditions we will probably can't ever observe directly. Off the top of my head, someone in my department is studying the behavior of charged particles around a black hole. Unless we're considering another universe with different laws, our laws of physics should hold anywhere.

But until some theory is actually noted through observation, it is mere conjecture. Last time I checked, there were something like 5 variants of string theory all jockeying for legitimacy, each as valid as the other. The problem with some mathematical model is that at every step of an analysis, a different approach can be taken when yields a different result. Then what? Moreover, sometimes the math gives a result that has no physical meaning whatsoever. People throw out analyses on a regular basis based on actual data. That's simply the way science works.

I have great respect for theoretical physicists (anyone who makes a living through pure brainwork earns a grudging respect from me), but it is always mindful to consider the validity of any given approach. In the same vein, our laws of physics are only true insofar as we do not find anything that forces us to reconsider them. For millennia, Euclidean geometry was held up as a fundamental axiom until Riemann came along and destroyed that idea. Newton's laws of motion were the be all, end all until Einstein showed up and rewrote the books. The flip side of the coin is that if someone comes up with a better, more accurate way of describing things, then people should be just as ready to accept it or find a counterexample. Nature of progress and all that.

 

[TheContact]

Speed of light is quite slow in relation to the universe. Definitely need to warp around somehow

 

[Tesseract]

y'all should watch star trek: enterprise because when you have faith of the heart you can do anything. fuck roemer, michelson and morely, interferometry, lorentz and fitzgerald, and that punk bitch einstein's special relativity.

also fuck mirrors, ty.

 

[Gotchaye]

I don't understand how the guy hopes to "close" the bubble on the other side. Is he only trying to demonstrate man-made warping of space by filling it with energy? There'd still be the negative energy issue.

 

[GungHo]

It all comes back to that life after death thread. They're not gonna figure this shit out in my lifetime. I won't get to know the terrible secret of space, and it pisses me off.

 

[rekameohs]

We don't even have a light speed ship yet.

This kind of travel is more likely than a ship that can travel the speed of light, actually.

 

[zoku88]

But until some theory is actually noted through observation, it is mere conjecture. Last time I checked, there were something like 5 variants of string theory all jockeying for legitimacy, each as valid as the other. The problem with some mathematical model is that at every step of an analysis, a different approach can be taken when yields a different result. Then what? Moreover, sometimes the math gives a result that has no physical meaning whatsoever. People throw out analyses on a regular basis based on actual data. That's simply the way science works.

I have great respect for theoretical physicists (anyone who makes a living through pure brainwork earns a grudging respect from me), but it is always mindful to consider the validity of any given approach. In the same vein, our laws of physics are only true insofar as we do not find anything that forces us to reconsider them. For millennia, Euclidean geometry was held up as a fundamental axiom until Riemann came along and destroyed that idea. Newton's laws of motion were the be all, end all until Einstein showed up and rewrote the books. The flip side of the coin is that if someone comes up with a better, more accurate way of describing things, then people should be just as ready to accept it or find a counterexample. Nature of progress and all that.

Your counter examples don't really hold up, though. At least, to the point, where you would call them 'mere conjecture'.

For each one:

Euclidean geoemetry isn't 'wrong' (as in, it's self consistent), it just doesn't accurately reflect reality. Although, it still describes the scale that most people care about. Nothing to do with Riemann, so not sure why you brought him up. As far as I can tell, Reimann did nothing w.r.t. geometry. (were you referring to calculus? I'm not sure why that would be relevant, though.)

Same thing for Newton's Laws of Motion. They're good for the scale that Newton was talking about. It just so happened that when you got really really small, they aren't accurate.

So, it's not like previous models are thrown out or anything, because they're still valuable.

To call them 'mere conjecture' is pretty silly. You can logically prove that things MUST be a certain way even without observation.

'Mere conjecture' wouldn't be as hardy as these theories and laws often are....

The problem with some mathematical model is that at every step of an analysis, a different approach can be taken when yields a different result.

There's a word for such models. It's 'broken'. Unless the 'different' results are equivalent (in which case, they're not really different anyway..)

Different approaches leaving different results is illogical, and therefore broken.

Newton chose to publish his proofs using geometric arguments (rather than calculus). Of course, either method would give you the same end result, it's just that calculus was new and you want people to actually be able to understand your proof.

 

[Bear]

But until some theory is actually noted through observation, it is mere conjecture. Last time I checked, there were something like 5 variants of string theory all jockeying for legitimacy, each as valid as the other. The problem with some mathematical model is that at every step of an analysis, a different approach can be taken when yields a different result. Then what? Moreover, sometimes the math gives a result that has no physical meaning whatsoever. People throw out analyses on a regular basis based on actual data. That's simply the way science works.

I have great respect for theoretical physicists (anyone who makes a living through pure brainwork earns a grudging respect from me), but it is always mindful to consider the validity of any given approach. In the same vein, our laws of physics are only true insofar as we do not find anything that forces us to reconsider them. For millennia, Euclidean geometry was held up as a fundamental axiom until Riemann came along and destroyed that idea. Newton's laws of motion were the be all, end all until Einstein showed up and rewrote the books. The flip side of the coin is that if someone comes up with a better, more accurate way of describing things, then people should be just as ready to accept it or find a counterexample. Nature of progress and all that.

Theoretical physics is a pretty broad field with multiple schools of thought. If well understood concepts are pushed to their theoretical limits, it can often predict any eventual observations accurately. It can have physical meaning if it chooses to work within that. Other times, you have what are essentially thought experiments. Physicists may create a conceptual particle (like a tachyon) just to determine certain properties that it must have to exist, and what problems would arise from those. That sort of work furthers general understanding, but it doesn't necessarily have any physical meaning. I suppose string theory would fall somewhere between those, though I'd argue it leans closer to the second.

Although this is straying pretty far from my original point, which is that "sample size" isn't a very meaningful concept in many areas of physics. The laws are inherent to our universe and aren't unique to Earth. Generally speaking, they will apply anywhere else as long as all differences are accounted for. Newton's Laws will work fine on any other planet to describe the forces it is designed to account for, sometimes that isn't enough but it doesn't make it any less valid.

 

[Foolworm]

Your counter examples don't really hold up, though. At least, to the point, where you would call them 'mere conjecture'.

That's because I was making a different point in each paragraph. The first paragraph was a specific refutation of Bear's point, while the second paragraph was a broader elaboration on the nature of science.

Even so, my point holds - a theory is conjecture until proven by observation. Euclidean geometry, Newtonian physics, these theories were regarded as true (and are still broadly used today) because all observations matched predictions made by said theory. Only when people made physical observations that these theories did not predict did their replacements gain legitimacy, and even then only because they explain away the contradictions to the pre-existing theory.

There's a word for such models. It's 'broken'. Unless the 'different' results are equivalent (in which case, they're not really different anyway..)

You conflate models and proofs. A model is not some step-by-step logic train that yields an inevitable result. At every step of modeling, assumptions have to be made, variables chosen, and constants defined. Any little change and poof! Something different pops up. Sure, you can argue that the model is broken but that is meaningless as all models are limited to their basic assumptions. The point is to build a model that works.

Although this is straying pretty far from my original point, which is that "sample size" isn't a very meaningful concept in many areas of physics. The laws are inherent to our universe and aren't unique to Earth. Generally speaking, they will apply anywhere else as long as all differences are accounted for. Newton's Laws will work fine on any other planet to describe the forces it is designed to account for, sometimes that isn't enough but it doesn't make it any less valid.

As I have stated before, our laws of physics are formulated based our observations. Thus far, our observations have been limited to the platform of Earth. Therefore, they are inherent to Earth, and not the Universe. That they will apply anywhere and everywhere else is an incredibly myopic perspective. For all I know, our current model of physics may have skewed by us being within the Sun's gravitational field (I am just throwing this out as an example). This is not to discredit our current knowledge of physics - it works, after all - but simply to point out that we are still very much limited, and that we should be ready to discard well-established theories if something better sprouts up. After all, our theories exist to explain reality, not the other way around. It was universally accepted that there was no speed limit until Einstein came along.

 

[Bear]

As I have stated before, our laws of physics are formulated based our observations. Thus far, our observations have been limited to the platform of Earth. Therefore, they are inherent to Earth, and not the Universe. That they will apply anywhere and everywhere else is an incredibly myopic perspective. For all I know, our current physics may have skewed by us being within the Sun's gravitational field. This is not to discredit our current knowledge of physics (it works, after all), but simply to point out that we are still very much limited, and that we can never rule out any possibility. Our theories exist to explain reality, not the other way around.

No theory can describe everything everywhere, but what we know should still describe what it is designed for. I'm not arguing that what we know is complete, anything short of a perfect GUT will only describe particular phenomena, but it will account for them beyond Earth. What you brought up would be an example of an influence that wasn't accounted for, but that doesn't invalidate the knowledge of what we understand. Previously, you brought up several theories claiming they weren't true, but used examples that only show that they weren't complete.

Although at this point we seem to be addressing different issues. You argue that what we know is not sufficient to describe everything, which is true, and I argue that what we know can still be applied everywhere (which, to my knowledge, is true). No theory is complete, but what we know should be universally valid for its designated purpose. Unless the particles that make up other parts of the universe are fundamentally different (which is possible, but is contrary to everything we know), they would be governed by the same laws.

 

[zoku88]

That's because I was making a different point in each paragraph. The first paragraph was a specific refutation of Bear's point, while the second paragraph was a broader elaboration on the nature of science.

Even so, my point holds - a theory is conjecture until proven by observation. Euclidean geometry, Newtonian physics, these theories were regarded as true (and are still broadly used today) because all observations matched predictions made by said theory. Only when people made physical observations that these theories did not predict did their replacements gain legitimacy, and even then only because they explain away the contradictions to the pre-existing theory.

Either you're grossly misusing or misunderstanding the meaning of conjecture.

Theories are not conjecture. They are mathematical proofs (well, the proven theories are, anyway). That is the exact opposite of conjecture. This is why we don't see contradictions to them, at least in their original scale/environment

You conflate models and proofs. A model is not some step-by-step logic train that yields an inevitable result. At every step of modeling, assumptions have to be made, variables chosen, and constants defined. Any little change and poof! Something different pops up. Sure, you can argue that the model is broken but that is meaningless as all models are limited to their basic assumptions. The point is to build a model that works.

This is different from what you originally said "ie, using a different mathematical approach would yield different results".

Any model where that would happen is broken. A model that is not self-consistent is not useful.

 

[akira28]

It's not really FTL travel anymore, but what if we did something along these lines?

-When technology becomes available to do so, create a Quantum Checkpoint. This functions sort of like a time machine, utilizing quantum entanglement to allow us free time travel as early as the creation and powering on of said Quantum Checkpoint.

-Create a Quantum Endpoint. This is a similar time machine that functions as a receiver node. Using the Quantum Checkpoint, scientists travel as close to the end of eternity as possible, and lay down the receiver node.

-Once the Checkpoint and Endpoint are in place, you're essentially allowed unlimited space-time movement just as long as the two don't run out of power (which we'll ignore for the sake of the example). In the event that one of two is destroyed, this timeline is now classified as a Beta Timeline.

-Beta Timelines should be regarded as failures, as the Checkpoint and Endpoint do not exist for eternity.

-There is a lone, paradoxical Alpha Timeline in which the Checkpoint and Endpoint make it all the way through their existences. In the event that the Checkpoint or Endpoint are destroyed in the Alpha, a duplicate is taken from one of the many tainted Beta Timelines to use as a replacement. Precision time-hopping could allow you to "Indiana Jones" the Quantum switch to avoid some sort of mass paradox.

-People in the Alpha Timeline actually use Beta Timelines as conduits, because we know they operate under similar properties as our own timeline. The Beta Timelines could arguably be considered parallel universes, and for safe travel one could simply go from point A to point B at the Beta Timeline's genesis (meaning there wouldn't be enough time for subversion of natural physics) and suspend their bodies (if we still have them) in cryo to emerge at whatever point is desired in the Alpha Timeline.

A contingency plan would be to create the Quantum Checkpoint and turn it on, and create the Quantum Endpoint but leave it off. A group of brave souls would wait with the Quantum Endpoint until the end of existence and turn it on at the last possible second, making it function as a sort of Pre-Alpha Timeline.

Keep in mind I have no idea how to science.

sounds too dangerous.

 

[Can Crusher]

I don't see how this is ever going to be possible.

 

[Foolworm]

No theory can describe everything everywhere, but what we know should still describe what it is designed for. I'm not arguing that what we know is complete, anything short of a perfect GUT will only describe particular phenomena, but it will account for them beyond Earth. What you brought up would be an example of an influence that wasn't accounted for, but that doesn't invalidate the knowledge of what we understand. Previously, you brought up several theories claiming they weren't true, but used examples that only show that they weren't complete.

Although at this point we seem to be addressing different issues. You argue that what we know is not sufficient to describe everything, which is true, and I argue that what we know can still be applied everywhere (which, to my knowledge, is true). No theory is complete, but what we know should be universally valid for its designated purpose. Unless the particles that make up other parts of the universe are fundamentally different (which is possible, but is contrary to everything we know), they would be governed by the same laws.

I will note that inapplicability is not the same as incompleteness or correctness. Einstein's theory did not 'correct' Newton, it replaced it altogether. That being said, Newton's laws are simple, elegant and powerful enough that it remains in widespread use. Euclidean geometry was simply inapplicable in, say, surveying and navigation due to the curvature of the earth; I will, however, concede that Euclidean geometry is a subset of Non-Euclidean geometry. That being said, the non-testable aspects of theoretical physics is quite unsettling to me. It brings up uncomfortable comparisons to, say, the luminiferous aether theory.

My point is not that we don't know everything - that is a triviality. My point is that all our knowledge thus far has been gleaned from observations made from a single point in space - Earth. The jump in applicability from Earth to the Universe is enormous, and cannot be made lightly. We need more platforms of observation in order to verify things - in a roundabout way, I wish the US would allot NASA more funding.

Either you're grossly misusing or misunderstanding the meaning of conjecture.

Theories are not conjecture. They are mathematical proofs (well, the proven theories are, anyway). That is the exact opposite of conjecture. This is why we don't see contradictions to them, at least in their original scale/environment

On the contrary, you are grossly misusing the word 'theory'. A theory is simply an explanation for something in the context of the scientific method. The theory of evolution is not mathematical, for instance.

A good theory gives useful information relating to the process it attempts to describe. Bad theories are quickly disproven and discarded. It does not mean they are not theories, simply they are invalid.

This is different from what you originally said "ie, using a different mathematical approach would yield different results".

Any model where that would happen is broken. A model that is not self-consistent is not useful.

The problem with some mathematical model is that at every step of an analysis, a different approach can be taken when yields a different result.

To get back on topic, FTL is a topic I don't much care for simply because it is so unrealistic. Even using Newtonian physics, applying the rocket equation to achieve a velocity of c for any significant mass is orders of magnitude of what is possible with the resources we currently have. All other methods of FTL are fantasies as far as I am concerned.

The most reasonable paper I have read on FTL posits that beyond c, the spacetime dimensions flip, i.e. a tachyon travels one-way through space but freely back-and-forth through time. While in appearance this violates causality, the mere constraint in what we call 'space' but a tachyon considers 'time' renders the matter moot.

 

[The Librarian]

I know I'm a bit late with this thread, but I wanted to add something here.

I think this is an important reminder

That isn't necessarily true, from what I've read. General relativity permits FTL travel so long as restrictions of special relativity are obeyed. The speed of light is a local speed limit. So, theoretically, were you to execute your ship's warp drive in "flat" space, there'd be no time dilation because the relativistic mass of the ship has not increased.

It's awesome that NASA is experimenting with FTL, but I think it's important to keep in mind that we don't need FTL to travel the galaxy. An ETC would be able to colonize the galaxy within a short few million years even at sub-light speeds. For example, a ship traveling at .1c would be able to reach Epsilon Eridani within 105 years. A hardy journey today, as most humans don't live that long, but by time we are able to achieve those speeds over long distances, who knows how long humans will live? Maybe 105 years will become modest.

 

[ThoseDeafMutes]

I know I'm a bit late with this thread, but I wanted to add something here.

That isn't necessarily true, from what I've read. General relativity permits FTL travel so long as restrictions of special relativity are obeyed. The speed of light is a local speed limit. So, theoretically, were you to execute your ship's warp drive in "flat" space, there'd be no time dilation because the relativistic mass of the ship has not increased.

Maybe I'm just tired, but the problem as I understand is that because there are no privileged frames of reference, other observers will be experiencing time dilation and from their perspective that is identical to a situation in which they weren't but you were. For instance if they are moving at 0.866 C relative to you and you are stationary, that's the same as if you were both moving at a lower speed, or if you were moving but they were stationary. So you can't really escape TD when trying to crunch the numbers.

It's awesome that NASA is experimenting with FTL, but I think it's important to keep in mind that we don't need FTL to travel the galaxy. An ETC would be able to colonize the galaxy within a short few million years even at sub-light speeds. For example, a ship traveling at .1c would be able to reach Epsilon Eridani within 105 years. A hardy journey today, as most humans don't live that long, but by time we are able to achieve those speeds over long distances, who knows how long humans will live? Maybe 105 years will become modest.

Space politicians don't want to plan that far ahead. Especially the space republicans.

 

[The Librarian]

Maybe I'm just tired, but the problem as I understand is that because there are no privileged frames of reference, other observers will be experiencing time dilation and from their perspective that is identical to a situation in which they weren't but you were. For instance if they are moving at 0.866 C relative to you and you are stationary, that's the same as if you were both moving at a lower speed, or if you were moving but they were stationary. So you can't really escape TD when trying to crunch the numbers.

Hm. Possibly. Perhaps I'm misunderstanding the source I'm referencing, as I had to go back and find the particular section needed to comment. I've been going through Stephen Webb's Where IS Everybody? and that's where I found the information. It's a good, but depressing, book. You should give it a read if you haven't already.

 

[OminoMichelin]

It's awesome that NASA is experimenting with FTL, but I think it's important to keep in mind that we don't need FTL to travel the galaxy. An ETC would be able to colonize the galaxy within a short few million years even at sub-light speeds. For example, a ship traveling at .1c would be able to reach Epsilon Eridani within 105 years. A hardy journey today, as most humans don't live that long, but by time we are able to achieve those speeds over long distances, who knows how long humans will live? Maybe 105 years will become modest.

The problem is that, leaving survival aside, no human will want to live on a space shuttle for 105 actual years. And those who will will either go insane/already are.

 

[The Librarian]

The problem is that, leaving survival aside, no human will want to live on a space shuttle for 105 actual years. And those who will will either go insane/already are.

It doesn't have to be a shuttle. A generational ship would, theoretically, be big enough to greatly reduce or negate such effects. And, again, the travel time of 105 years is at only one tenth the speed of light.

 

[Oblivionmancer]

I don't find arguments against a possible FTL future on the basis of its 'conceptual impossibility' particularly compelling. Of course it's wrong to suggest that it just takes more power or whatever to solve it, it does indeed require a new concept of how the world works. The argument from past impossibilities disappearing is still potent, not on the basis of any formal logical proof, but on that of a robust preponderance of evidence. It happens every time. We define the limits of our world through the lens we happen to experience it through. It was conceptually impossible to sail around the world when we thought it was flat. The solution wasn't more power, it was to revise our understanding of the world to one that was more correct.

I don't know if the same possibilities exist for this problem but there is no reason in principle why they can't. Of course the predictive and explanatory abilities of modern physics reach much further than any before, but even they aren't perfect, are tainted by dogma in the face of conflicting data, as the greater and greater necessity of more and more dark matter to explain discrepancies in the data proves. Such 'discoveries' sound an awful lot like the epicycles of old to me.

The point is that our current understanding of the universe, as broad, deep, and robust as it often seems to be, is not some axiomatic collection of truths read from the language the universe was written in. They are carefully created, endlessly tested and observed, but nonetheless merely constructed by limited and biased human minds. Like so many theories, so many so well known truths before it, our current understanding of the universe is absolutely subject to reaching the end of its usefulness, its ability to accurately explain and predict.

We are such tiny, limited creatures, so limited by our perceptions; what we think we know of the universe today may describe merely the barest beginnings of the totality of the cosmos. With our five little senses, our three little dimensions, we may merely be floating on the surface of an endlessly deep cosmic ocean.

So yeah, impossibility most certainly is a constantly receding bright-line. Sometimes it inches along, and sometimes on the back of one person's one moment of insight, followed by a lifetime of effort, it can be pushed by leaps and bounds in what amounts to a moment.

I'm no scientist of course, and can only defer to those more knowledgeable on the limits of physical causation. Causation, though, isn't just a variable in an ad hoc equation for the universe, it is a concept that doesn't require our particular physical 'laws' to exist. And as a concept, it doesn't have a speed limit, a unit of time doesn't have finite dividability.

Don't mistake me, it might be that everything is as it seems, and this impossibility will never be retired. But nothing, nothing in our physics, however thoroughly considered, nothing in our observations, no matter how often repeated and documented, makes it impossible in principle.

 

[empty vessel]

Read the article for details. I dunno about you guys but it's news to me that faster than light travel has already happened (in nature). Could we see this happen in our lifetimes? Like, when we're 150 and regrowing our organs with 22nd century stem cell technology?

Your government is putting a damper on that by misguidedly sharply cutting its spending. That means you die before science can progress to save you.

I'm serious, your government is killing you via austerity.

 

[ThoseDeafMutes]

I don't find arguments against a possible FTL future on the basis of its 'conceptual impossibility' particularly compelling. Of course it's wrong to suggest that it just takes more power or whatever to solve it, it does indeed require a new concept of how the world works. The argument from past impossibilities disappearing is still potent, not on the basis of any formal logical proof, but on that of a robust preponderance of evidence. It happens every time. We define the limits of our world through the lens we happen to experience it through. It was conceptually impossible to sail around the world when we thought it was flat. The solution wasn't more power, it was to revise our understanding of the world to one that was more correct.

It doesn't happen every time, though. New theories often provide more limitations than old ones do. Before thermodynamics, there was no reason to believe that you couldn't build perpetual motion machines. Before relativity, there was no reason to believe that you couldn't simply accelerate infinitely with no upper bound on velocity. New physical theories provide new possibilities but never assume that it's always going to work in your favor. Your example of sailing around the world is a bit spurious because if anybody did try it, they would discover how wrong it was (e.g. it's a "theoretical assumption" that nobody bothered to test). I mean academics already knew the Earth was round since before Christ, but...

People arguing "maybe future physics we don't know about now will let me have my way" are doing so primarily out of a desire to see it go that way, not because there is rational reason for it to do so. Lacking any knowledge of the situation, future physics would have a 50/50 shot of making it harder to travel through space at high speeds, not easier. Actually it's worse odds than that, because we know that new physical theories must give the same answers as the old ones where the old ones have been confirmed by experimentation. And Relativity has historically had immense predictive power, with essentially all of its theorized implications having been discovered, ranging from gravitational time dilation (see: timekeeping on space stations) to mass-energy equivalence (see: nuclear weapons).

We also have indirect evidence coming from other branches of physics. Quantum phenomena that are "actually FTL" have been discovered, but thus far they have all preserved the idea that information cannot transfer at speeds in excess of C. QM and Relativity are both "correct" in their respective domains, yet are incomplete. However when we do finally unify them in some sort of GUT, it would be really fucking strange if the light-speed limit preserved by both of them separately turned out to be something we could break.

 

[GloveSlap]

I don't find arguments against a possible FTL future on the basis of its 'conceptual impossibility' particularly compelling. Of course it's wrong to suggest that it just takes more power or whatever to solve it, it does indeed require a new concept of how the world works. The argument from past impossibilities disappearing is still potent, not on the basis of any formal logical proof, but on that of a robust preponderance of evidence. It happens every time. We define the limits of our world through the lens we happen to experience it through. It was conceptually impossible to sail around the world when we thought it was flat. The solution wasn't more power, it was to revise our understanding of the world to one that was more correct.

I don't know if the same possibilities exist for this problem but there is no reason in principle why they can't. Of course the predictive and explanatory abilities of modern physics reach much further than any before, but even they aren't perfect, are tainted by dogma in the face of conflicting data, as the greater and greater necessity of more and more dark matter to explain discrepancies in the data proves. Such 'discoveries' sound an awful lot like the epicycles of old to me.

The point is that our current understanding of the universe, as broad, deep, and robust as it often seems to be, is not some axiomatic collection of truths read from the language the universe was written in. They are carefully created, endlessly tested and observed, but nonetheless merely constructed by limited and biased human minds. Like so many theories, so many so well known truths before it, our current understanding of the universe is absolutely subject to reaching the end of its usefulness, its ability to accurately explain and predict.

We are such tiny, limited creatures, so limited by our perceptions; what we think we know of the universe today may describe merely the barest beginnings of the totality of the cosmos. With our five little senses, our three little dimensions, we may merely be floating on the surface of an endlessly deep cosmic ocean.

So yeah, impossibility most certainly is a constantly receding bright-line. Sometimes it inches along, and sometimes on the back of one person's one moment of insight, followed by a lifetime of effort, it can be pushed by leaps and bounds in what amounts to a moment.

I'm no scientist of course, and can only defer to those more knowledgeable on the limits of physical causation. Causation, though, isn't just a variable in an ad hoc equation for the universe, it is a concept that doesn't require our particular physical 'laws' to exist. And as a concept, it doesn't have a speed limit, a unit of time doesn't have finite dividability.

Don't mistake me, it might be that everything is as it seems, and this impossibility will never be retired. But nothing, nothing in our physics, however thoroughly considered, nothing in our observations, no matter how often repeated and documented, makes it impossible in principle.

I agree with you. Our current understanding is sufficient to distinguish what is hard and what is easy. Long distance space travel is one of the hard things, but much is still up in the air. Some willpower and a few hundred/thousand/million years can still do wonders when it comes to such a challenge.

 

[Oblivionmancer]

It doesn't happen every time, though. New theories often provide more limitations than old ones do. Before thermodynamics, there was no reason to believe that you couldn't build perpetual motion machines. Before relativity, there was no reason to believe that you couldn't simply accelerate infinitely with no upper bound on velocity. New physical theories provide new possibilities but never assume that it's always going to work in your favor. Your example of sailing around the world is a bit spurious because if anybody did try it, they would discover how wrong it was (e.g. it's a "theoretical assumption" that nobody bothered to test). I mean academics already knew the Earth was round since before Christ, but...

There's some fair enough points there, I shouldn't have phrased my point so absolutely. My broader point, anyway, was not meant to speak in guarantees, but possibilities. I'm not really sure why it matters when we knew the earth was round, the only point is that a narrow or limited enough perspective can make anything seem impossible, not just practically but conceptually.

People arguing "maybe future physics we don't know about now will let me have my way" are doing so primarily out of a desire to see it go that way, not because there is rational reason for it to do so.

This, however, pisses me right off. It is condescending and rude, because it supposes that you have a better knowledge of my own internal mental states and motivations than I do, and/or because it suggests that I'm being dishonest about my presented motivations. So no, I don't have a particular way that I want it to go, I just genuinely disagree with your perspective on how confident we can be that our current models are actually correct, because they rely so completely on a dogma of a science which is the sole creation of a species that is tiny and limited in its perceptions. We weigh them so heavily because of their predictive and explanatory power, which seems robust against the pieces of reality our limited ability to perceive allow us to test them against; this does not imbue them with the power of axiomatic truth, nor any kind of descriptive or predictive power regarding phenomena we cannot perceive.

Lacking any knowledge of the situation, future physics would have a 50/50 shot of making it harder to travel through space at high speeds, not easier. Actually it's worse odds than that, because we know that new physical theories must give the same answers as the old ones where the old ones have been confirmed by experimentation. And Relativity has historically had immense predictive power, with essentially all of its theorized implications having been discovered, ranging from gravitational time dilation (see: timekeeping on space stations) to mass-energy equivalence (see: nuclear weapons).

We also have indirect evidence coming from other branches of physics. Quantum phenomena that are "actually FTL" have been discovered, but thus far they have all preserved the idea that information cannot transfer at speeds in excess of C. QM and Relativity are both "correct" in their respective domains, yet are incomplete. However when we do finally unify them in some sort of GUT, it would be really fucking strange if the light-speed limit preserved by both of them separately turned out to be something we could break.

The reason these explanations lack weight is because they only describe the physical universe as we can perceive/comprehend it. I'm not suggesting that a new physics will replace the descriptive power of existing theories within their own limited context; I'm suggesting (merely the possibility) that these explanations of what part of the cosmos we can perceive or detect or examine with our limited senses and instruments only capture a part (perhaps a very small part) of the totality of the universe. It's hard to nail down what this refers to in precise language, because I'm trying to describe something which I have thus far defined only as beyond our ability to perceive. The best bet, I guess, is by analogy, like a bacteria's perception of the known universe as compared to ours, our perception might be compared to the totality of existence. Why that matters in the pursuit, for example of FTL travel, is that the bacteria is no less able to interact with the rest of the universe in spite of its complete lack of awareness of it. Where the divide becomes relevant is in our capacity to consider these greater spheres beyond our windows to the cosmos, and attempt to interact with them in a more intentional way.

Of course, the truth is we already do this; when we talk about quantum mechanics and string theory, we're stretching to the edge of what we can knowingly interact with; why then can't we push further, to forces whose impacts are too large or distant to even register in our perspective? Once more, these are all just maybes, but that's no reason to dismiss them out of hand.

I mean, it's pretty clear you're not going to be on board with any of this, and that's fine. I just think we lose perspective on how tiny our window into the world is, and just how little we might be seeing of it.

 

[Jal]

I don't see how this is ever going to be possible.

You'll feel stupid when we've all got our Google Warp Drives to go down to the shops.

 

[CurlySaysX]

What happens when you hit a bit of space rock when you are travelling at those speeds?

 

[Freshmaker]

So why is it different that we don't have something of sufficient power to break beyond the speed of light? It's a considerably larger problem but to believe that it can never and will never be done is short sighted. There are times when things are believed to have gone FTL i.e. during the Big Bang as theorized by scientists as well so that being the case, believing that it has been done, we can assert that it is beyond our tech not that it is beyond our reach.

That's assuming that a big bang explosion would be operating under the same physical laws that the current universe operates under.

 

[mario_O]

What happens when you hit a bit of space rock when you are travelling at those speeds?

Dr Kaku has you covered

 

[3phemeral]

Dr Kaku has you covered

Doesn't really answer the question (technically), since you're not actually traveling at the speed of light. But because it's impossible anyway, that's the best answer Curly's going to get.

 

[Jhriad]

This is just theoretical stuff, a lot more time (and money) will be needed to actually make a FTL ship.

I'm ready to Kickstart this bitch.

 

[Cyber Caesar]

We need to put a black hole in front of the ship. We need something very hot and very heavy. How does one ride a supernova?

 

[Ether_Snake]

The whole idea of traveling faster than light is pointless. Wormholes gets around this issue!

Also, there's no official NASA or space exploration thread?:|

 

[Clevinger]

Also, there's no official NASA or space exploration thread?:|

There's this.

 

[J2 Cool]

OP fucked up when he mentions FTL. It's Warp Drive, not FTL.

Seriously, there's no worse luck you can wish upon an experimental spaceship than calling it a FTL ship. This is my biggest concern with the project.