=Special Theory Of Relativity=

[MeJennifer]

I do not know whether an observer on a spaceship traveling at extremely high speeds would be able to detect the mass increase...

If he would it would mean that the theory of relativity is incorrect!

 

[JesseM]

While my understanding of relativity is rudimentary, from what I recall, the mass of an object is relative to its velocity.

That's only if you're using a concept called "relativistic mass", and most physicists prefer to dispense with this and just use "mass" to mean the rest mass (which is equal to relativistic mass in the object's own rest frame). See does mass change with velocity?

I do not know whether an observer on a spaceship traveling at extremely high speeds would be able to detect the mass increase, but an observer in an inertial reference frame should be able to, since the force required to increase the velocity of a spaceship traveling at .9 c, say by 10 km/s, would be much greater than the force required to increase the velocity of a spaceship by 10 km/s from rest.

Yes, but you could also explain this just by saying the energy required to increase the velocity by a given amount is greater the higher the starting velocity, and the energy required to accelerate an object to c would be infinite.

 

[vociferous]

In theory relativity need not forbid objects which always travel at faster than the speed of light though, these theoretical objects are called "tachyons". They probably don't exist because they would cause problems with causality (a tachyon signal could arrive before it was sent in some frames), though. Here's a more practical way to translate unscientific's scenario though. Imagine you have a large grid of pixels where each pixel can be made transparent or opaque to light electronically. Then you could create an image of fan blades made out of a collection of opaque pixels, and by rapidly switching pixels between transparent and opaque, the image of the blades could rotate around as fast as you want, even faster than light. No actual object would be traveling faster than light in this scenario, it would be an illusionary form of FTL like the FTL laser spot on the surface of the moon or the superluminal scissors, but in terms of whether light could pass through or not it would be as if you had actual fan blades moving at FTL speeds. Again, the answer to whether a light pulse would get through or be blocked would just depend on things like the width of the pixellated blades, how fast they appeared to be moving, and the length of the light pulse.

I suppose that would be possible with some kind of perfect transitor, though it could not run on electrons since they always have to move slightly slower than light (personally, I would settle for LCD's that switched fast enough to watch football on without seeing a little bluring during fast plays).

If the photons were not all moving in the same phase, since they travel at the same speed as the fan blade, at least a few should be able to make it through, and it would probably look like like passing through a semi-transparent object. If the photons were all in the same phase, then you might be able to get some interesting patterns.

Would there be any interesting relativistic or quantum effects?

 

[Schrodinger's Dog]

Look up this one, is pretty good:

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/muon.html#c1

Look up Ives and Stilwell, they are a pais of antirelativists that proved Einstein right. Ives died denying it.

Thanks for that, I was told perhaps eroneously that this experiment only confirmed time dilation? How is the muons length contraction effect isolated from the more significant time dilation effect?

I always thought Schrodinger's dog referred to Snoopy, in the Peanuts comic strip. I suppose he's really Charlie Brown's dog, but I have this memory of him draped in gaga fashion (imitating Lucy) over Schrodinger's piano.

It's actually in reference To Erwin Schrodinger himself and his obvious dislike of cats , thus my avatar, because I assume Schrodinger was a dog man

 

[selfAdjoint]

It's actually in reference To Erwin Schrodinger himself and his obvious dislike of cats , thus my avatar, because I assume Schrodinger was a dog man

Boy are you off base! Erwin Schroedinger was a notorious cat LOVER! His use of a cat in his thought experiment was to show the bitterness of his contempt for Copenhagen quantum physics (he was a coworker and rival with Einstein in developing a unified field theory based on GR).

The current imbroglio over string theory is nothing new; big time physicsits live and breathe these theories, and are ready to fight for their beliefs.

 

[Schrodinger's Dog]

Boy are you off base! Erwin Schroedinger was a notorious cat LOVER! His use of a cat in his thought experiment was to show the bitterness of his contempt for Copenhagen quantum physics (he was a coworker and rival with Einstein in developing a unified field theory based on GR).

The current imbroglio over string theory is nothing new; big time physicsits live and breathe these theories, and are ready to fight for their beliefs.

I never new he was a cat lover, but I did know the suposition was eroneous since it's a thought experiment and the cat is irrelevant thus the wink, the joke is meant to be sarcasticly sarcastic,but if he is a cat lover it's an even less substantial joke now thanks

I have no problem with string theory at all, it seems wonderfully imaginative, it just seems a little bit too suppositional,in that it conveniently invents dimensions that can never be perceived to solve a problem that would in my very humble opinion, be served by trying to posit theories that might at least be testable, in my lifetime or ever, also the reason why I feel a little purturbed by many worlds intepritation.

I feel a little jipped by the idea of maths alone describing the universe, a way of garnering breakthrough results that lead to practical application. I guess I shouldn't be descriminating without knowing a large amount about the subject but at least with the current theories the evidence was there wating to be found. I'm not so sure about string theory. Is it useful though, undoubtablly, were imaginary numbers usefull 434 years ago, if nothing else it might illuminate where we've gone wrong. Does learning about one theory in isolation lead to ideas to dismiss another in a vaccuum; I guess no matter how leary you are of potentially unrealisable theories, they do give some a groundwork for new ideas. And what else are physisists meant to do while they're spending ten years getting funding and toying with their experiments to prove the more mainstream? Got to keep the grey matter ticking over

 

[selfAdjoint]

Whenever you try to think about the world you have two choices: rhetoric and mathematics. Rhetoric is very popular and you can see ewxamples of it all over the web, and on our own well-beloved Philosophy boards as well. But rhetoric has a big problem going anywhere. You get down one or two deduction levels and everything seems to fuzz out into a morass. The reason for this is that rhetoric doesn't have a methodology to vet its concepts, and the result is that all the tight reasoning in the world can't save a sloppy idea. If you like this is an example of arguing too far up Korzybski's abstraction tree.

So you want tightly-defined concepts, and that means math (or logic, but logic and math are joined at the hip). Hence the people whose response to the puzzles of the world is to build mathematical models and make predictions from them - and these people go back to the Old Kingdom of Babylon, if not to Ur of the Chaldees - are notably more successful, and can even get other people and governments to pay them money to do do their thing, which philosophers pretty much can't.

 

[clj4]

Thanks for that, I was told perhaps eroneously that this experiment only confirmed time dilation? How is the muons length contraction effect isolated from the more significant time dilation effect?



It's actually in reference To Erwin Schrodinger himself and his obvious dislike of cats , thus my avatar, because I assume Schrodinger was a dog man

In an earlier post you said :

I seem to remember time dilation has yet to be proven experimentally, is that still the case?

I gave you a couple of well known experiments that showcase time dilation, so I don't understand why you come back with:

Thanks for that, I was told perhaps eroneously that this experiment only confirmed time dilation?

Weren't the two links clear enough?

 

[M1keh]

Ok. I've been looking at this on and off for the last two years and I've seen the same arguments time and time again, but it just doesn't look right.

Relativity gives rise to too many questions that can't be answered. Supporters label these as 'anomalies' and sweep them under the carpet, usually hiding behind the maths, but there seem to be some very serious problems with a constant speed of light !

 

[M1keh]

Can somebody confirm my 'understanding' of the rules :

* Constant speed of light in all frames of reference
* Time Dilation
* No one F.O.R is special.

No arguments, can't have one without the others ?

 

[baryon]

Maybe a frame of reference traveling at the speed of light would be special because all other reference frames would be traveling slower than it. This special frame of reference would have a very large amount of energy. Supposedly an infinite amount. Time would be almost at a standstill and particles that decay quickly in the lab would exist for many years.