MajinVegeta Posted April 21, 2003 Author Posted April 21, 2003 Oh my, there is no need to argue with one another. Fafalone, will you be so kind as to explain why v(t) is absurd? I sort of get your point, but just to be sure, I'd like to know.
fafalone Posted April 21, 2003 Posted April 21, 2003 If you drop something, it's velocity function is 9.8t... this is clearly not equal to c, and since it changes over time it's not constant. The effects of relativity at slow speeds are negligible.
blike Posted April 21, 2003 Posted April 21, 2003 If you drop something, it's velocity function is 9.8t... this is clearly not equal to c Right, thats on the xyz coords. The motion through time makes up for the rest of the speed. must.stop.going.in.circles
blike Posted April 21, 2003 Posted April 21, 2003 Yet another source to add to my library of sources confirming magnitude of 4-vector motion is always C. Special Relativity Page 35-36. Here's a good excerpt: "Thus |u| = c in all frames. This trivial "proof" is a good model for problem-sovling in special relativity: identify something which is frame-independant, transform into a frame in which it is easy to calculate, and calculate it. The answer will be good for all frames. The reader may find this a little strange. Some particles move quickly, some slowly, but for all particles, the magnitude of the 4-velocity is c. But this is not strange, because we need the magnitude to be a scalar, the same in all frames. If I change frames, some of the particles that were moving quickly before now move slowly, and some of them are stopped altogether. Speeds (magnitudes of 3-velocities) are relative; the magnitude of the 4-velocity has to be invariant".
fafalone Posted April 21, 2003 Posted April 21, 2003 u = xi+yj+zk+tl and |u|=c but v(t) = :pdif:u/:pdif:xi + :pdif:u/:pdif:yj + :pdif:u/:pdif:zk and |v| <> c, which is what i've been saying.
blike Posted April 21, 2003 Posted April 21, 2003 Originally posted by fafalone u = xi+yj+zk+tl and |u|=c but v(t) = :pdif:u/:pdif:xi + :pdif:u/:pdif:yj + :pdif:u/:pdif:zk and |v| <> c, which is what i've been saying. brb, need to laugh. last night you were arguing 'Since space-time cannot be separated, your q and V vectors are meaningless. Just because a book says something doesn't make it true... don't forget that not all math people show is correct. Think back to the people who came here proposed GUTs." you were saying that my vectors were meaningless, etc etc (which proved the exact same thing; magnitude of v^2=c^2). So I showed ANOTHER mathmatical model for it. Now you claim thats what you've been saying all along. I highly doubt you believed that |u|=c, otherwise you would have said it earlier on because thats exactly what I've been saying. Yet you claim "Wow, you really have no idea whatsoever what you're doing." nice job trying to reduce this argument to a simple wordgame. admit defeat and move on.
KHinfcube22 Posted April 22, 2003 Posted April 22, 2003 Why does everyone act as if C is so fast? I man, light isn't that quik on a galactic scale. Why does everyone act as if it is the "Ultimate Speed"?
MajinVegeta Posted April 23, 2003 Author Posted April 23, 2003 Originally posted by KHinfcube22 Why does everyone act as if C is so fast? I man, light isn't that quik on a galactic scale. Why does everyone act as if it is the "Ultimate Speed"? Because, up to now, traveling faster than light is paradoxical. See the first post on this thread. Also, you should consider the fact that everything is relative.
Radical Edward Posted April 23, 2003 Posted April 23, 2003 The Lorentz transforms are in the Relativity announcements if anyone wants them.
KHinfcube22 Posted April 24, 2003 Posted April 24, 2003 But wouldn't we also think sound was the "Ultimate" speed if we never broke the barrier?
fafalone Posted April 24, 2003 Posted April 24, 2003 I believe superluminal motion is possible in Lorenztian relativity...
blike Posted April 24, 2003 Posted April 24, 2003 The problem is getting there without having to go through C
MajinVegeta Posted April 24, 2003 Author Posted April 24, 2003 Originally posted by fafalone I believe superluminal motion is possible in Lorenztian relativity... Really??!! cool! tell me more, if you can!
MajinVegeta Posted April 24, 2003 Author Posted April 24, 2003 Originally posted by KHinfcube22 But wouldn't we also think sound was the "Ultimate" speed if we never broke the barrier? it would have been considered ONE of the ultimate speeds.
Radical Edward Posted April 24, 2003 Posted April 24, 2003 Originally posted by KHinfcube22 But wouldn't we also think sound was the "Ultimate" speed if we never broke the barrier? there is nothing that mathematically suggests that you can't travel at, or faster than the speed of sound though. It is just any old speed, which depends on the properties of the medium. the speed of light in a vacuum isn't.
JaKiri Posted April 24, 2003 Posted April 24, 2003 Originally posted by Radical Edward there is nothing that mathematically suggests that you can't travel at, or faster than the speed of sound though. It is just any old speed, which depends on the properties of the medium. the speed of light in a vacuum isn't. 'You can't compare these two things, because you have to specify a medium for this one, and obviously this one where I specify a medium is different because it doesn't need a medium despite me having to specify one.'
Radical Edward Posted April 24, 2003 Posted April 24, 2003 Originally posted by MrL_JaKiri 'You can't compare these two things, because you have to specify a medium for this one, and obviously this one where I specify a medium is different because it doesn't need a medium despite me having to specify one.' <MrL_JaKiri> it's just a matter of stating that empirically newtonian physics holds past the speed of sound thanky for pointing out my fuzzy/incorrect line of argument
JaKiri Posted April 24, 2003 Posted April 24, 2003 Originally posted by Radical Edward <MrL_JaKiri> it's just a matter of stating that empirically newtonian physics holds past the speed of sound Or 'close enough to' at least
KHinfcube22 Posted April 26, 2003 Posted April 26, 2003 Is there anything we know about that is faster than light?
MajinVegeta Posted April 27, 2003 Author Posted April 27, 2003 No, there is nothing at all that actually can travel faster than light. Black holes are an example: their escape velocity is c+(from the event horizon, that is) and there aren't particles that come straight out of the EH. could particles travel faster than light at a quantum level? that is, at Planck's Length?
Raider Posted April 28, 2003 Posted April 28, 2003 Why would a black hole have an escape velocity? If gravity is geometrical and the singularity is in fact a singularity, the warping of the space-time continium must be infinite. That would mean nothing gets out at any speed short of infinity, with slight exception resulting from the uncertainty principle.
Radical Edward Posted April 28, 2003 Posted April 28, 2003 Originally posted by KHinfcube22 Is there anything we know about that is faster than light? yes. electrons often travel faster than light.
Radical Edward Posted April 28, 2003 Posted April 28, 2003 Originally posted by MajinVegeta could particles travel faster than light at a quantum level? that is, at Planck's Length? Originally posted by Raider That would mean nothing gets out at any speed short of infinity, with slight exception resulting from the uncertainty principle. General relativity and Quantum Mechanics do not mix.
fafalone Posted April 28, 2003 Posted April 28, 2003 Originally posted by Raider Why would a black hole have an escape velocity? If gravity is geometrical and the singularity is in fact a singularity, the warping of the space-time continium must be infinite. That would mean nothing gets out at any speed short of infinity, with slight exception resulting from the uncertainty principle. A singularity is an infinitely small point, the escape velocity approaches infinity as you approach the singularity.
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