Kopeikin and "the speed of gravity"

Dr. VanFlandern:
Thank you for answering my question but Wow!, now I'm really confused.

I thought in Special Relativity that NO time reversal is possible.

If the above is true then how could you accelerate FASTER then the speed of light? Whether it is acceleration or speed or velocity, I can't see the difference if it is past the speed of light.

Are you saying that Special Relativity is wrong and that you can go back in time? I'm really confused. Sorry to bother you, thank you for your answer.

Just learning!
Magoo

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I thought in Special Relativity that NO time reversal is possible.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

So-called "tachyons" are hypothetical entities with imaginary mass that always travel faster than light, according to SR.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>If the above is true then how could you accelerate FASTER then the speed of light?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

You can't. Acceleration is not velocity, and does not have velocity units. Acceleration, big or small, cannot be compared with speed, big or small.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Whether it is acceleration or speed or velocity, I can't see the difference if it is past the speed of light.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

That is a problem you need to study up on. Pick up an introductory physics book and learn about units and dimensions.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Are you saying that Special Relativity is wrong and that you can go back in time? I'm really confused.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Nothing I said here bears on either matter. But in general, I've argued that SR is wrong (Lorentzian relativity is more likely to be right), but that going back in time violates physical principles (e.g., the causality principle) and will always be impossible. -|Tom|-

Dr. VanFlandern, I see your points. Yes, I do need to study more.

Would someone please help me understand the difference between velocity and acceleration? Isn't acceleration just the rate in change of velocity over time? If so, how could it be that the velocity part within acceleration could be faster than the velocity that is not part of acceleration. I'm sorry but this seems really confusing to me.

Just learning!
Magoo

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Would someone please help me understand the difference between velocity and acceleration? Isn't acceleration just the rate in change of velocity over time?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Yes, that is one working definition.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>If so, how could it be that the velocity part within acceleration could be faster than the velocity that is not part of acceleration.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

It can't. Acceleration can't be "faster" than anything because it is not a speed. Your question is not unlike asking why I can't travel at a speed longer than the Earth. Speed is related to length in the same way that acceleration is related to speed.

Let's use your definition of acceleration. No matter how limited speed might be, why can't the rate of change of speed still be anything at all? Of course, if acceleration were huge, it could not be sustained for very long of speed would go over the speed of light. But we are talking about the speed and acceleration at an instant, not how long they last. I can drive 60 miles per hour without driving either 60 miles or for an hour.

The center of a "black hole" (not that such things exist in reality) is called a "singularity". It is a mathematical point where matter is concentrated in an infinitesimal volume. The accelerations there can be literally infinite. Yet in legitimate mathematics, a point mass following Newton's laws can pass through a singularity and never exceed the speed of light. That is because the high acceleration period lasts a very short time, with infinite acceleration lasting only an instant.

Ignore this last paragraph if you are not already familiar with these concepts. -|Tom|-

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>

have you ever thought of the possibility that there is "something" else correcting for the delay, like a cosmological constant, a zero-point energy or a dark matter? why does it have to be your way?

<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Mark, let us perform another experiment.

There is long vertical rod of length L. This rod is suspended to support. You are just lying below this rod with your forehead just fraction of millimeter right below lower end of this rod.

Now if Tom Van Flandern release this rod, the weight of rod alone is not enough to crush your head. But consider that the rod is suspended and we place heavy stone on upper end of this rod. Now we are ready to do our experiment.

At t = 0, Tom release the suspended rod so that it moves down right on your forehead. But at the same instant t = 0, stone falls off from upper end of this rod.

Now there is great deal of confusion with what speed this information regarding falling off i.e. separation of stone will reach to lower end of rod. If the speed is c, then

(1) Aaccording to Dr. Kopeikin, c = speed of gravity.
(2) According to USENET SRians crackpots, c = de-compression wave,
(3) According to Tom Van Flandern, c = billion time faster than light.

As this information regarding separation of stone from upper end has not reached to lower end during time interval t = L/c, the lower end will behave as if nothing is happened and the lower end will still have "weight" of this stone even if the stone is separated.

So during this time interval t, the rod moves down and crushes your head. You are dead.

Now I am standing near upper end of rod. During same time interval t, the stone falls on my head and I am also dead.

Now even if we both are dead, I ask you:

_______________________________________________________________

How can one stone kill two persons at two different points in space during same time interval t?
_______________________________________________________________

I haven't explained how to "create" excess energy during propagation delay of gravity. But don't you see one "excess" death here?

Now answer this question:

________________________________________________________________

How exactly your GR is going to "correct" the propagation delay and bring back dead person to life?
_________________________________________________________________


-Abhi.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[Abhi]There is long vertical rod of length L. This rod is suspended to support. You are just lying below this rod with your forehead just fraction of millimeter right below lower end of this rod.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>The reaction of the "forehead" spreads up the rod as a compression wave, the parts of rod react by sending a compression wave back down. So the force upon the forehead grows gradually. It's most obvious when the rod is considered consisting of loosely connected parts - "atoms".

So that "(2) According to USENET SRians crackpots, c = de-compression wave" appears closest to truth.