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Re: Does General Relativity Predict Gravitational Waves?

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jay moseley wrote:

> Thomas Lahn wrote...
>>> Your fallacy here is: Straw man. Nobody has claimed that "strain [would
>>> not be] strain".
> 
> <https://en.wikipedia.org/wiki/List_of_fallacies#Red_herring_fallacies>

You have misquoted this.  I referred you to that list instead, so that you 
can read there what a straw man fallacy is, and why you committed it there.
 
>>I have said that there are different kinds of strain. The one that you are
>>referring to (classical, non-relativistic) was _not_ observed at the LIGO
>>detectors; the >one I referred to (relativistic) was.
> 
> Reminds me of the line. All men are equal but some are more equal than
> others.

What you do not realize is that strain can be caused by different phenomena, 
and so there are different kinds of strain.  And the simple truth of the 
matter is that, AISB, the kind of strain that you referred to (classical, 
non-relativistic) was _not_ observed; the kind of strain that I referred to 
(relativistic) *was* observed.
 
> You seem to not understand something about what LIGO observed.

No, *you* do not understand it *at all*.  Finally get yourself *informed*.

> They did not observe "relativistic" waves.

With a probability of more than 95 %, the LIGO team did observe 
_gravitational_ waves.

> What happened was the two arms of the interferometer physically 
> contracted/expanded.

Correct.  There is no contradiction.  You must realize that those arms exist 
in our universe, and are therefore a part of spacetime.  Loosely speaking, 
if spacetime expands, the arm expands; if spacetime contracts, the arm 
contracts.  That is, we *measure* it to be longer or shorter than before 
because it took *light* less or more time to travel the distance.  Because 
the speed of light is constant and the same in all frames of reference, 
measuring the travel time of light is an excellent way to measure distance.  
(In the case of LIGO, however, the fact that light can behave like a wave 
was used; when waves interfere, the interference can be constructive or 
destructive or something in-between.)

> Hence the path lengths differed over time.

In fact, they not just differed arbitrarily over time, but they 
*oscillated*.  They oscillated precisely in the way predicted by Einstein in 
1916: one of the arms was shortened *by the same ratio* that the other arm’s 
length increased *at the same time*.  Hence the characteristically 
*oscillating* *interference pattern* in the detector of the (Michelson) 
*interferometers* that the LIGO experiments essentially are.

Computer models of the experiment when measuring gravitational waves had 
been created before, based on the Einstein field equations.  The 
observations matched those models almost *precisely*.

The observations matched those models almost precisely *two times*, *in two 
different places* in the United States (Livingston, LA; and Hanford, WA).  

The oscillations had been observed in the second place *exactly as in the 
first place* at *exactly the time they should have been observed* if a 
phenomenon traveled from the first place to the second one *at the speed of 
light* (which only light and gravitational waves can do, and it was not 
light this time).

Meticulous preparations and precautions made sure that no other known 
phenomenon could be responsible for those oscillations at either site.  
Hence, there is no reasonable doubt that what has been observed were 
gravitational waves that had been produced by the merger of two black holes 
with the masses that have been reported, at the distance from Earth that has 
been reported, and in the region of space that has been reported.

> That is not a relativistic phenomena.

Incorrect.

Since you appear to have problems finding the relevant statements in the 
references that I gave you, here is the reference to the part in the press 
conference video where the explanations of what happened and how it was 
measured begin:

<https://youtu.be/aEPIwEJmZyE?t=265>

If you still cannot understand it after watching the video from that time 
index (0:04:25) to ca. 0:29:45 (but feel free to watch beyond), you can 
watch Brian Greene explaining it for laymen in about 8.5 minutes in “The
Late Show”:

<https://www.youtube.com/watch?v=ajZojAwfEbs>

If it is still unclear, you can ask a *smart* question in 
<news:sci.physics.relativity> where this is on-topic instead, and I (or if 
someone else is faster than me, someone else) will explain it to you. 

<http://www.catb.org/esr/faqs/smart-questions.html>

I am even willing and prepared then to give you an analogy for gravitational 
waves for laymen that hopefully you can understand.

However, if you still just continue to plainly deny what has happened 
*despite the overwhelming evidence to the contrary* (and without 
substantiating your rather outlandish claims yourself), I will add you to my 
killfile, as such behavior by you would show that you have disconnected 
yourself from both reality and reason, and that further communicating with 
you is a waste of time.  You have been warned.


PointedEars
-- 
I heard that entropy isn't what it used to be.

(from: WolframAlpha)

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Thread

Re: Does General Relativity Predict Gravitational Waves? Helénē Swanhild <helenes@gardenclosure.org> - 2016-03-03 19:29 +0000
  Re: Does General Relativity Predict Gravitational Waves? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 12:35 +0100
    Re: Does General Relativity Predict Gravitational Waves? jay moseley <jaymoseley@hotmail.com> - 2016-03-05 05:25 -0800
      Re: Does General Relativity Predict Gravitational Waves? Sam Wormley <swormley1@gmail.com> - 2016-03-05 08:08 -0600
      Re: Does General Relativity Predict Gravitational Waves? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 17:42 +0100
        Re: Does General Relativity Predict Gravitational Waves? jay moseley <jaymoseley@hotmail.com> - 2016-03-05 12:19 -0800
          Re: Does General Relativity Predict Gravitational Waves? Sam Wormley <swormley1@gmail.com> - 2016-03-05 14:21 -0600
          Re: Does General Relativity Predict Gravitational Waves? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 22:01 +0100
            Re: Does General Relativity Predict Gravitational Waves? jay moseley <jaymoseley@hotmail.com> - 2016-03-05 14:14 -0800
              Re: Does General Relativity Predict Gravitational Waves? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-06 16:24 +0100
                Re: Does General Relativity Predict Gravitational Waves? "hanson" <hanson@quick.net> - 2016-03-06 08:22 -0800
                Re: Does General Relativity Predict Gravitational Waves? jay moseley <jaymoseley@hotmail.com> - 2016-03-07 00:44 -0800
                Re: Does General Relativity Predict Gravitational Waves? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-07 20:52 +0100
                Re: Does General Relativity Predict Gravitational Waves? "hanson" <hanson@quick.net> - 2016-03-07 12:54 -0800
      Re: Does General Relativity Predict Gravitational Waves? Odd Bodkin <bodkinodd@gmail.com> - 2016-03-07 09:09 -0600

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