Could a ship travel ftl

[_Owen_]

There were loopholes in Einsteins' theory, as it says in the article that you quoted, the scientists do not believe that this violates Einsteins theories.

Either way, matter can not pass the speed of light, which is more the focus of this thread.

Owen Macri

[Avatar28]

In simple terms, a law describes an observation of something that occurs in the natural world while a theory attempts to describe how/why something occurs.

A law is an observable fact, like Newton's laws of motion. This happens. A theory would try to explain WHY Newton's laws happen.

That said, Einstein's theory of relativity will likely have to some day be altered, but by and large has been proven valid. But like Newton's laws have since been clarified and exanded upon by Einstein and others, so too will Quantum/String/other theories expand and clarify Einstein's laws but will probably never completely invalidate them.

As for what I mean, for most purposes, classical Newtonian physics are quite sufficient for most work (including interplanetary spaceflights), even though Einsteinian physics can describe things in more detail (they're also much more complex and don't make a significant difference until you get to extremes of speed and mass).

[_Owen_]

Those are good points, however Einsteins' Theories will not be altered, other theories will replace them, only Einstien could change his theories, I somehow don't think that that is going to happen. Sorry to nitpick.

Owen Macri

[SeaBee]

As long as E=MC^2 holds true to a ship, then that ship will never travel faster than light. The only way to exceed the speed with a mass of any significant use beyond science reserch is to alter either the properties of the space the ship travels through, or the properties of the ship itself. E.E. "Doc" Smith used a field generated around a craft which negated the mass and inertia, allowing speeds far in excess of light with only a small powerplant. The down side of this was that when the field was switched off the ship immediately regained any movement it had prior to the field's activation, causing the ship to lurch off in a different direction.
With other shows, such as SG-1, Andromeda, Farscape, etc. the ship is forced into a "sub-space" or "hyper-space" where, magically, the theory doesn't apply.

But as for real ships in real space, then the most that can be expected is maybe 10% of light, driven by a nuclear powered plasma drive, before the energy requirements exceed the ships capacity to generate it.

As an aside, I saw a programme about the future of spaceflight recently, that had a prototype plasma drive featured in it. It is only a static model at the moment, but produced hundreds of times more thrust than a conventional rocket motor of a similar size.

[Avatar28]

As long as E=MC^2 holds true to a ship, then that ship will never travel faster than light. The only way to exceed the speed with a mass of any significant use beyond science reserch is to alter either the properties of the space the ship travels through, or the properties of the ship itself. E.E. "Doc" Smith used a field generated around a craft which negated the mass and inertia, allowing speeds far in excess of light with only a small powerplant. The down side of this was that when the field was switched off the ship immediately regained any movement it had prior to the field's activation, causing the ship to lurch off in a different direction.
With other shows, such as SG-1, Andromeda, Farscape, etc. the ship is forced into a "sub-space" or "hyper-space" where, magically, the theory doesn't apply.

But as for real ships in real space, then the most that can be expected is maybe 10% of light, driven by a nuclear powered plasma drive, before the energy requirements exceed the ships capacity to generate it.

Relativistic effects really aren't noticable at 10% of c. Time dilation doesn't begin to occur much at all until about .4 c and increases parabolically from there so that around .7c you have approximately a factory of 2 time dilation (meaning that for every minute on your ship, two occurs to a "stationary" outside observer). That said, the ACTUAL mass of your space craft doesn't really increase, only it's APPARENT mass.

[lethalfang]

As far as we know gravity is proven, it is considered a law, "The Universal Law of Gravitation." It states that any object has gravity and will attract every other object. This is stated in Sir Issac Newtons equation Fg=Gm1m2/r^2. For the moment this is a Law, qunatum theory is just that, theory, but I got your point.

Owen Macri

The difference between law and theory is that, a so-called "law" is a conclusion based on numerous empirical observations. It generates conclusions based on past observations, but it does not attempt to explain the phemonema. Take Newton's law of gravity, for instance, the equation reigns true in every instance we know, so we regard that as a law. Einstein paints a different picture of the nature of gravity, but the Newton's law is still valid because the equation still works amazingly well.
A theory, on the other hand, is an attempt to explain the observation. It can be regarded as a true scientific theory, if predictions based on the theory are observed. Take Einstein's theory of relativity for instance. He pictured a universe where space can be curved in order to explain some phemonema. There are important consequences of his theory, such as time dilation for objects near gravity or traveling near speed of light. Both of these predictions are later observed, and it is a very good theory.
The theory of relativty does not explain everything. Most likely, it is a large scale limit of a so-called "theory of everything." As Newton's laws are adequate for most everyday life, Einstein's laws are and will be adequate for most things. A more complete theory, however, is likely needed to explain the origin of the universe and things like expansion of the universe, dark matters, etc.

[Darth Buddha]

Great post, lethalfang.

As a philosopher of science, I've never liked the usage of the word "Law" as it is applied to science. The name is misleading in the colloquial sense of the word. It in closer to a postulate in geometry than anything else... Newton's Postulate of Gravity would convey the EXACT sense that Law does not.

[Jarnin]

Could a ship travel ftl?

Alcubierre Drive, AKA Warp Drive.

[Darth Buddha]

Alcubierre Drive, AKA Warp Drive.

COOL!

Probably not possible, but fun to think about!

[_Owen_]

That does pretty much explain the concept of Warp Drive, it is not the best article I have read but it does explain it in simple terms, nice post.

Owen Macri

[lethalfang]

What exactlly was observed though?

The only proff I have ever really read of was that on really fast jet airplanes some atomic clocks have been a little slow. Not even noticable to a human. That's not enough proff to me to say that there is an ultimate speed barrier.

The most direct evidence for special relativity comes from particle accelerators (aka atom smashers): accelerate charged particles using powerful magnetic field.
The difference in power between the early version and the newest ones are enormous. The relativistic effect between them are also enormous: radioactive decay slows down drastically. The mass increases drastically. The kinetic energy (due to increasing mass) are so much more powerful that they can break up atoms into more fundamental subatomic particles.
The velocity, however, lingers around 0.9999999999 the speed of light.

Here is the amazing part. Einstein predicted all these (cosmic speed limit, time dilation, mass increase, etc), way before anyone attempted to do experiments like that.

[_Owen_]

That is the amazing part, he could do this because he wasn't even a scientist he was a mathematician that used math to ddiscover new aspects of science.

But basically by our knowledge matter can not travel faster than the speed of light.

Owen Macri

[Jarnin]

Here is the amazing part. Einstein predicted all these (cosmic speed limit, time dilation, mass increase, etc), way before anyone attempted to do experiments like that.

That's the entire basis of scientific theory; it's not amazing, it's a requirement.

Theories are supposed to make predictions of future events. If they don't then they're not theories.

[_Owen_]

Good point.

Owen Macri

[lethalfang]

That's an amazing theory.
At the end of the 19th century, men thought we knew everything about physics, and only details are left to be discovered.
Einstein's theory changed our view of the universe.