Faster than light

Originally posted by sonhouse
From Brazil? My daughter and her husband teach music and physics respectively at Federal University and they might be convinced to translate if you can provide the link.

It is from a Portuguese Physicist. This is the man: http://cfcul.fc.ul.pt/equipa/3_cfcul_elegiveis/croca/croca.htm (I once had a class with him 😵 ) and this is the book: http://www.wook.pt/ficha/dialogos-sobre-a-fisica-quantica/a/id/193775

In the past he had already written a book on nonlinear QM, but it was a technical book. This most recent one is directed at the general public.

In his page you can find a lot of good articles written in English that touch on some of the topics of a nonlinear theory of QM.

Originally posted by sonhouse
If you could do that it would still take about 3 seconds before planet B knew anything about it. Just like if you could teleport the sun 10 light years away instantly, the rest of the solar system would not know for a while. Like about 9 minutes before Earth would react.

How do you know this? Are you basing this on gravitons not exceeding the speed of light? Have there been any experiments to test what happens to an object when a close is removed?

Originally posted by uzless
How do you know this? Are you basing this on gravitons not exceeding the speed of light? Have there been any experiments to test what happens to an object when a close is removed?

Well to my surprise here is a link supporting the propagation of gravity:

http://www.metaresearch.org/cosmology/speed_of_gravity.asp

Have you read this work? It seems to boil down to proving there is no aberration effect in gravity like what is seen in visual aberrations (the position of the moon during solar eclipses, etc.)

I must confess total ignorance of this effect. Do you have further details of this?
What I wonder is if gravity does indeed propagate at some 2 E10 times c, can this effect be used to create some kind of communications system going that much faster than c.

Or indeed, allows somehow travel faster than c. Or if there is no possible connection the the idea that gravity may respond faster than c.

I think this paper was written about 13 odd years ago, I wonder if there have been updates. I also notice a layman's article in Analog listed at the end.
Analog is a science fiction magazine that has layman science articles in every issue. It would appeal to science fiction fans that would question the GR and SR idea of c as being the speed limit of motion.

Even if gravity can respond billions of times faster than c does not inherently allow motion of matter faster than c.

I would like to see some work exploring the idea that if there were gravitational aberration effects it would automatically increase angular momentum in orbiting bodies as stated by that piece.

It is a lot to read for sure.

A bit of further reading in a Wiki piece:

Aberration in general relativity

The finite speed of gravitational interaction in general relativity may at first seem to lead to exactly the same sorts of problems with the aberration of gravity that Newton was originally concerned with. In general relativity, however, (similar to the field theories above), gravitomagnetism effects cancel out the effects of aberration.[clarification needed] As shown by Carlip, in the weak stationary field limit, the orbital results calculated by general relativity are the same as those of Newtonian gravity (with instantaneous action at a distance), despite the fact that the full theory gives a speed of gravity of c.[12] Although the calculations are considerably more complicated, one can show that general relativity does not suffer from aberration problems just as electromagnetic retarded Liénard–Wiechert potential theory does not. It is not very easy to construct a self-consistent gravity theory in which gravitational interaction propagates at a speed other than the speed of light, which complicates discussion of this possibility.[13]

So GR introduces the concept of gravitomagnetism to constrain the speed of gravity to that of c.

So it seems you would also have to disprove gravitomagnetism also to claim gravity goes faster than c.

Here is a link to the 2002 experimental measurements of the speed of gravity, at first thought to be disproved but later to be confirmed, it seems so far:
http://www.csa.com/discoveryguides/gravity/overview.php

Originally posted by TitusvE
Also waves in football stadiums can go faster than light theoretically. This is how it works: give all football fans a very accurate watch and let them look at there seat-number. Suppose this seat number is i for a specific fan. Then instruct all people in the stadium to jump up and throw their hands in the air at a specific time given by x + i*d/c with x t ...[text shortened]... or any other time during the match), d the distance between the seats, and c the speed of light.

But in this case information is not travelling with the wave - thus not violating relativity.

Originally posted by twhitehead
But in this case information is not travelling with the wave - thus not violating relativity.

Indeed. If you wait for your right neighbour you are too late.
Therefore you cannot pass on information. My previous post on quantum tunneling, however,
does seem to violate special relativity. However the signal-noise ratio makes it impossible
to actually send and receive signals over large distances due to the exponential decay of the
signal