# Can a mini cooper travel FTL?

1. Jan 25, 2004

### jgravatt

Special relativity asserts that an object approaching the speed of light would also increase its mass to the point that even an infinite supply of fuel/energy would not be able to push that little go-kart passed the critical limit of C, right - close enough maybe? Why is C the limit? Is it because space itself is one entity networked together through an infinite number of strings, "things" or whatever. We are limited because we are traveling through space. What if we could travel -through- something that is in space. Something like an anti-space tube (sounds goofy, I know). This tube does not contain the interconnected network of things that limit our speed. Instead, there is nothing or a better yet, a different kind of
network. Since there is nothing or something different, we would not be limited to C, only limited to the property of that network - which could be faster or slower than C. I'm going out on a limb here but assumming something that I don't know. I have heard that the universe is expanding at a rate faster than the speed of light. Maybe that could be explained by this new network. Within space - our universe- , the only network is the one that limits C. Outside of our space, the area that the universe expands -through- may contain a different network of things that allow the universe to travel through it much faster than C can travel on out network.

Not intending to insult any of you by over explaining, but here is a visual.

You have two different drag strips next to each other. In the left lane, Albert Einstein is driving a photon car on a drag strip made up of strings or whatever we currently think the universe is made of. In the right lane, you are driving a mini cooper on a drag strip made up of a diffrent kind of network of things. When the light turns green the photon car can't go any faster than the strip allows - which in his case is C. The mini cooper also can't go faster than his strip allows, but his strip allows him to go faster than C. Another thought - Special Relativity says we can't travel faster than C, maybe C is only C because it is limited on our network. If C was traveling on a different network, maybe it travels even faster.

Jeremy

2. Jan 26, 2004

### FUNKER

Word up.
atleast your thinkin man. i have had the same thoughts as you have and i would also be interested in knowing the answer, but thats just it: no one knows the answer especially wat is 'past'our universe, at best the answer is an assumption, and you know what they say about assumptions.........

3. Jan 26, 2004

### KingNothing

So...you're saying the area outside of our universe (which is assumed to be none. contrary to logic, not contradictiory to any facts) might have different laws of physics? Yeah, I've thought about that kind of stuff too. I think most people do at one point or another.

4. Jan 26, 2004

### Staff: Mentor

What you are describing sounds an awful lot like a wormhole.

5. Jan 26, 2004

### jgravatt

Yeah, I was thinking that while I was typing. Maybe worm holes use the same network that may be used outside of the universe to allow things to travel hyper C. Maybe Einstein was still right about C being the absolute speed limit. Maybe electromagnetic radiation is the most simple and most efficient method at propagating energy from one place to another. If that is the case, his limit still holds, but maybe C is even faster than what we think it is (outside of our network that is). Which brings me to my next thought - Why do so many people want to be able to travel FTL? Is it because to travel anywhere in the universe in a timely manner would require such a great speed? What if the speed of light was a billion times faster than what we think it is? Would we need to travel that fast or would 186,000 miles per second still be sufficient for us to travel throughout the universe? Thinking about it, it makes sense to have an ultimate speed limit - you have an environment governed by rules, it doesn't seem logical to make a claim that something is limitless in a rule rich environment? I think it is a pretty cool idea that C is still the limit, but at the same time it may be greater than anyone ever imagined!

Jeremy

6. Jan 26, 2004

### pallidin

I have always felt that C is a ridiculous limit, given the aspects of the universe. If nothing else, it seems like an incredibly low "speed limit" with respect to concepts such as infinity.
Though no-one could ever define infinity, yet, what would be the ratio of C to infinity? .000000000000001 and much less?
Surely there must be much, much higher speed potentials than C.
Oh well, guess I may never see them, as none has been demonstrated.

7. Jan 26, 2004

### chroot

Staff Emeritus
Uh... the ratio of infinity to a real number? That's infinite. If c was .000000000000001 times infinity, then infinity is 1000000000000000 c. Not quite!

- Warren

8. Jan 26, 2004

### plum

To explore some portion of our galaxy with any dignity, we ought to be able to cover a radius of about 100 light years, since that is the approximate range in which Earth-like planets that possibly harbor intelligent life would be.(making the journey worthwhile). It is feasible that technology such as matter/antimatter fusion could get us up to around 86% of light speed, taking this journey some 250 odd years to complete (10 generations of astronaut families living onboard, many of whom might never see Earth during their lifetimes.)

So FTL travel would sure make things easier, and the crew would be far less bored.

9. Jan 27, 2004

### pallidin

Jeeze, I know that! I wasn't trying to be specific. Just an illustration that C is much less than infinite, as is any defined number(as we all know). I did use the words "much less" in my original post.
Of course, any number is infinitely less than infinity, so any number is definitely "much less"
Sorry for the confusion. I am not that good at expressing my thoughts correctly.

10. Jan 28, 2004

### franznietzsche

The reason c is the limit is because of the minkowksi metric to which Special relativity adheres. The lorentz transformation, which determines how mass grows with increased velocity is derived from it.

The idea that there is nothing outside the universe isn't contrary to logic, by definition the universe is everything that exists, so there can be nothing outside of it. And even if we were to remove the term universe and just say we are in a closed system that contains every thing we can observe, then nothing outside this colloquial "universe" could affect us, so its really moot.

The wormhole idea is just a shortcut through space-time though, made possible by the fact that GR dictates that reality can be represented as a pseudo-Riemmanian manifold think of it as a twisted sheet, all the matter in th universe existing on the surface. If you go through the sheet (a 3 dimensional straight line in this example) you would take what wuold effectively be a wormhole. An iteresting though which just occurred to me, to take a shortcut between two points on a 2 dimensional manifold (the sheet) you take a 3 dimensional path, thus a wormhole between two points on a four dimensional manifold would ahve to be at least 5-dimensional.

11. Jan 29, 2004

### ewoodlief

The limit of any real number over x, as x approaches infinity, is zero. So c over infinity is equal to zero, and not "infinite" as you suggested.

12. Jan 29, 2004

### ewoodlief

Furthermore, faster-than-light travel circumvents the effect of time dilation. On the topic of light speed possibly varying from the speed of gravitational propagation, should this be the case then one need only travel "faster-than-gravity" to avoid this effect.

13. Jan 29, 2004

### chroot

Staff Emeritus
No. As I precisely said,

$$\frac{\infty}{x}\ \textrm{where}\ x \in \mathbb{R} = \infty$$

- Warren

14. Jan 29, 2004

### chroot

Staff Emeritus
A particle travelling faster than light would simply experience time dilation that is imaginary. If you call that "cirumventing," so be it.

- Warren

15. Jan 29, 2004

### franznietzsche

beat me too it. Faster than light travel IS NOT POSSIBLE in relativity, you would have to completely discard the theory in order for it to work.

Now for the sake of progress that may not be a bad idea, but discarding it just because you don't like the no faster than light travel is not. If you're going to discard a theory you have to do so because it makes incorrect predictions, and relativity has never failed in its predictions except at the quantum level.

the only way in relativity to get the effect of faster than light travel is through a wormhole. However mathematically such structures are notoriously unstable and not likely to naturally permit passage.

16. Jan 30, 2004

### AWolf

No matter which way you work it, Relativity implies it can't be done.

The problem with Relativity is that there are two basic theories, General and Special, for which the results are the same, but for different reasons.

I propose an additional theory, The Extraordinary Theory of Relativity, which states that there is a governing factor to the speed of light and it can be circumvented.

17. Jan 30, 2004

### Staff: Mentor

Not quite. As the names would imply, SR is a special case, GR is an extension to a more general case.

If they were two different explanations of the same thing, there'd be an obvious contradiction there.

18. Jan 30, 2004

### franznietzsche

I said you would have to discard relativity (as you quoted). Thus the implications would be irrelevant because you would be creating a new theory from scratch. However as i said, this is a poor basis for discarding a theory simply because one does not like the prediction, and is a sure sign of unproffesionalism and bias (something that is unfortunately too often seen in the scientific community). A theory should only be discarded when its predictions prove false, not when someone dislikes its implication that interstellar travel is impratical at best.

Also SR and GR do not ahve different reasons. The only difference is that SR assumes that there is no gravity, whereas GR makes the exact same predictions in the absence of gravity or in locally lorentzian frames. They are not different theorie in anyway. GR is merely an extension of special relativity,

Last edited: Jan 30, 2004
19. Jan 31, 2004

### ewoodlief

Sorry, I misinterpreted your misinterpreted response to pallidin's original post stating that, essentially, c is infinitesimally small compared to what one would "quantify" as infinity. Our equations are both true, as they are reciprocal.

20. Jan 31, 2004

### ewoodlief

True, I was merely adding to the discussion as to another repercussion of said travel--should one figure out how to achieve such an improbability.