[Physics] Physics Digest, Vol 21, Issue 6

Thu Dec 6 17:32:42 CET 2018

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On Thu, Dec 6, 2018 at 7:00 PM <physics-request at tuks.nl> wrote:

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> Today's Topics:
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>    1. Re: Gravitational Time Dilation and Gravitational Redshift -
>       two separate things? (carmam at tiscali.co.uk)
>    2. Re: Gravitational Time Dilation and Gravitational Redshift -
>       two separate things? (Ilja Schmelzer)
>    3. Re: Gravitational Time Dilation and Gravitational Redshift -
>       two separate things? (Doug Marett)
>    4. Re: Gravitational Time Dilation and Gravitational Redshift -
>       two separate things? (Ilja Schmelzer)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 5 Dec 2018 15:45:15 +0000 (GMT)
> From: "carmam at tiscali.co.uk" <carmam at tiscali.co.uk>
> To: <dm88dm at gmail.com>,  General Physics and Natural Philosophy
>         discussion list <physics at tuks.nl>
> Subject: Re: [Physics] Gravitational Time Dilation and Gravitational
>         Redshift -      two separate things?
> Message-ID:
>         <26455713.1280411544024715978.JavaMail.defaultUser at defaultHost>
> Content-Type: text/plain; charset="utf-8"
>
> Doug, you must specify what type of clock you are using. In a larger/more
> intense gravitation field, an atomic clock slows down and a pendulum clock
> speeds up. In a smaller/less intense field, the opposite happens. The
> gravitational redshift of light theory is wrong, as shown in this web page
> http://www.extinctionshift.com/
> <https://mailtrack.io/trace/link/07fca2175c8b16f970ae6b08bb3f06761fb1f64e?url=http%3A%2F%2Fwww.extinctionshift.com%2F&userId=890907&signature=734542f2b494382d>
> by Henry Dowdye.
> Tom Hollings
>
>
>
> ----Original Message----
>
> From: dm88dm at gmail.com
>
> Date: 04/12/2018 21:12
>
> To: "General Physics and Natural Philosophy discussion list"<
> physics at tuks.nl>
>
> Subj: [Physics] Gravitational Time Dilation and Gravitational Redshift -
>       two separate things?
>
>
>
> Hi All,
>     This just came up in a question I had to my website - it has to do
> with the Pound-Rebka experiment and whether gravitational time dilation of
> clocks and gravitational redshift of EM are two different things or the
> same thing. The problem is set out by L.B. Okun is plain language in an
> article here: https://arxiv.org/pdf/hep-ph/0010256.pdf
> <https://mailtrack.io/trace/link/8c1efc12c43d22b47871a45ab606cbec846f0181?url=https%3A%2F%2Farxiv.org%2Fpdf%2Fhep-ph%2F0010256.pdf&userId=890907&signature=41f13a9f3384ab4b>
>  The essence of it is that if you take a clock and move it from the ground
> to the top of a tower, the clock should speed up in it's rate at the higher
> altitude. If you then send an EM signal from this clock back to the ground,
> Einstein says that the EM should be blue-shifted. However, this would mean
> that the signal sent to the ground has now been blue-shifted TWICE, once
> due to the clock speeding up,  and once due to the fall of the EM through
> the gravitational gradient.
> However, the Pound-Rebka experiment finds that it is blue-shifted only
> once. So which effect is redundant, gravitational time dilation of clocks
> or gravitational red-shift of light? They can't be the same thing, since
> the latter is an operation performed on the EM during transit, and is
> supposed to make it bend. And the former is something which happens to
> clocks independent of EM signals sent between them.
> Interestingly, the experiment proposed by Okun to answer the question was
> performed in a slightly different form by Tom Van Baak as described here:
>
>
> http://leapsecond.com/great2005/
> <https://mailtrack.io/trace/link/d2fac4150c0a7de55b3b73c4ac60b190a444379e?url=http%3A%2F%2Fleapsecond.com%2Fgreat2005%2F&userId=890907&signature=eda01d7e43153d31>
> Another link that is useful is the paper here which examines the math used
> in the Pound-Rebka experiment and finds it is full of errors!
>
> http://milesmathis.com/pound.html
> <https://mailtrack.io/trace/link/e4b7403f8f07d3d7a652859de2844b30ae4a8a73?url=http%3A%2F%2Fmilesmathis.com%2Fpound.html&userId=890907&signature=767c166a9ed7123c>
> Just wondering if anyone else is aware of this apparent contradiction in
> the relativistic thinking : )
>
> Doug
>
>
>
>
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>
> ------------------------------
>
> Message: 2
> Date: Wed, 5 Dec 2018 21:49:56 +0100
> From: Ilja Schmelzer <ilja.schmelzer at gmail.com>
> To: General Physics and Natural Philosophy discussion list
>         <physics at tuks.nl>
> Subject: Re: [Physics] Gravitational Time Dilation and Gravitational
>         Redshift - two separate things?
> Message-ID:
>         <CAAKQs18_+0t4ur4CbhjN1X5n7vuCj1YiSq+-LR9MDSJokg=
> XGQ at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> No, the signal will be blue-shifted only once.
>
> This can be best seen if one replaces the wave by a hand-waving person
> and looks at the time when the light signal of "hand up" and "hand
> down" arrive.
>
> If we look at this in coordinates which are natural for a stable
> configuration, thus, a metric of the form g_mn (x^i) dx^m dx^n with
> the metric coefficients depending only on the spatial coordinates, and
> assume the handwaving guy as well as the observer at rest, the light
> rays for "hands up" and for "hands down" are the same trajectories,
> only with a shift in the time coordinate t.
>
> Thus, from point of view of the background time coordinate, there is
> no change in the frequency.  Thus, the only change in the frequency is
> because of the clocks (which have to be used to measure the frequency
> of the hand-waving).   So, they are the same thing.
>
> 2018-12-04 22:12 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
> > Hi All,
> >
> >     This just came up in a question I had to my website - it has to do
> with
> > the Pound-Rebka experiment and whether gravitational time dilation of
> > clocks and gravitational redshift of EM are two different things or the
> > same thing. The problem is set out by L.B. Okun is plain language in an
> > article here: https://arxiv.org/pdf/hep-ph/0010256.pdf
> <https://mailtrack.io/trace/link/d7dde1f3304439a3e8c1f967b067e50dcde5403a?url=https%3A%2F%2Farxiv.org%2Fpdf%2Fhep-ph%2F0010256.pdf&userId=890907&signature=6e9293f4162a165f>
> >    The essence of it is that if you take a clock and move it from the
> > ground to the top of a tower, the clock should speed up in it's rate at
> the
> > higher altitude. If you then send an EM signal from this clock back to
> the
> > ground, Einstein says that the EM should be blue-shifted. However, this
> > would mean that the signal sent to the ground has now been blue-shifted
> > TWICE, once due to the clock speeding up,  and once due to the fall of
> the
> > EM through the gravitational gradient.
> > However, the Pound-Rebka experiment finds that it is blue-shifted only
> > once. So which effect is redundant, gravitational time dilation of clocks
> > or gravitational red-shift of light? They can't be the same thing, since
> > the latter is an operation performed on the EM during transit, and is
> > supposed to make it bend. And the former is something which happens to
> > clocks independent of EM signals sent between them.
> > Interestingly, the experiment proposed by Okun to answer the question was
> > performed in a slightly different form by Tom Van Baak as described here:
> >
> > http://leapsecond.com/great2005/
> <https://mailtrack.io/trace/link/f85df1c386ed60dc6e788ab2fb734da1f2fde96d?url=http%3A%2F%2Fleapsecond.com%2Fgreat2005%2F&userId=890907&signature=7fcc406ef30bb106>
> >
> > Another link that is useful is the paper here which examines the math
> used
> > in the Pound-Rebka experiment and finds it is full of errors!
> >
> > http://milesmathis.com/pound.html
> <https://mailtrack.io/trace/link/bc814198648c994b9849802e9f5bfa3931fb237b?url=http%3A%2F%2Fmilesmathis.com%2Fpound.html&userId=890907&signature=6cc9068790d9aa86>
> >
> > Just wondering if anyone else is aware of this apparent contradiction in
> > the relativistic thinking : )
> >
> > Doug
> >
>
>
>
> ------------------------------
>
> Message: 3
> Date: Wed, 5 Dec 2018 16:30:44 -0500
> From: Doug Marett <dm88dm at gmail.com>
> To: General Physics and Natural Philosophy discussion list
>         <physics at tuks.nl>
> Subject: Re: [Physics] Gravitational Time Dilation and Gravitational
>         Redshift - two separate things?
> Message-ID:
>         <
> CAMSRO3ROJTOuR-DJcT3ZD8YTnYBsUO6-Q-rcsF0sUXc0O6bgFw at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> Hi Ilja,
>
>     Yes, I agree with you that " the only change in the frequency is
> because of the clocks (which have to be used to measure the frequency of
> the hand-waving", but the red-shift of the light can't be "the same thing"
> in my mind because, as you say, from the "point of view of the background
> time coordinate, there is no change in frequency".
> So if there is no change in frequency from the source to the receiver,
> there is no relativistic mechanism by which the EM wave is made to bend,
> since the bending is supposed to be caused by the progressive change in
> frequency through the gradient. Quite literally, for EM waves approaching
> the earth at an angle, the portion of the wavefront closer to the earth
> must contract compared to the portions further away, eliciting a
> progressive bend towards the surface, and Einstein attributes this to a
> change in frequency of the wave acted upon by the grav. gradient, which is
> something physical independent of the clocks. Einstein's idea also creates
> another paradox, that a receiver on the surface will receive more
> wave-fronts than are emitted by the transmitter at altitude - if this were
> true we would have a free-energy generating device!
>
> I think the only way out of this is to argue that it is the change in the
> speed of light with altitude and the associated change in wavelength that
> causes light to bend in the gradient, and frequency remains preserved.
> Einstein himself said in 1911 that this explanation was equivalent to his
> own (except for the energy change). Then there is only the one frequency
> effect due to the clocks and no problem with free energy. But then the
> black hole theory has to be a fiction.
>
> Doug
>
>
> On Wed, Dec 5, 2018 at 3:52 PM Ilja Schmelzer <ilja.schmelzer at gmail.com>
> wrote:
>
> > No, the signal will be blue-shifted only once.
> >
> > This can be best seen if one replaces the wave by a hand-waving person
> > and looks at the time when the light signal of "hand up" and "hand
> > down" arrive.
> >
> > If we look at this in coordinates which are natural for a stable
> > configuration, thus, a metric of the form g_mn (x^i) dx^m dx^n with
> > the metric coefficients depending only on the spatial coordinates, and
> > assume the handwaving guy as well as the observer at rest, the light
> > rays for "hands up" and for "hands down" are the same trajectories,
> > only with a shift in the time coordinate t.
> >
> > Thus, from point of view of the background time coordinate, there is
> > no change in the frequency.  Thus, the only change in the frequency is
> > because of the clocks (which have to be used to measure the frequency
> > of the hand-waving).   So, they are the same thing.
> >
> > 2018-12-04 22:12 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
> > > Hi All,
> > >
> > >     This just came up in a question I had to my website - it has to do
> > with
> > > the Pound-Rebka experiment and whether gravitational time dilation of
> > > clocks and gravitational redshift of EM are two different things or the
> > > same thing. The problem is set out by L.B. Okun is plain language in an
> > > article here: https://arxiv.org/pdf/hep-ph/0010256.pdf
> <https://mailtrack.io/trace/link/334d230de32cf827b58b49ff84a9ac1fcb893f21?url=https%3A%2F%2Farxiv.org%2Fpdf%2Fhep-ph%2F0010256.pdf&userId=890907&signature=0635205b48fb96ec>
> > >    The essence of it is that if you take a clock and move it from the
> > > ground to the top of a tower, the clock should speed up in it's rate at
> > the
> > > higher altitude. If you then send an EM signal from this clock back to
> > the
> > > ground, Einstein says that the EM should be blue-shifted. However, this
> > > would mean that the signal sent to the ground has now been blue-shifted
> > > TWICE, once due to the clock speeding up,  and once due to the fall of
> > the
> > > EM through the gravitational gradient.
> > > However, the Pound-Rebka experiment finds that it is blue-shifted only
> > > once. So which effect is redundant, gravitational time dilation of
> clocks
> > > or gravitational red-shift of light? They can't be the same thing,
> since
> > > the latter is an operation performed on the EM during transit, and is
> > > supposed to make it bend. And the former is something which happens to
> > > clocks independent of EM signals sent between them.
> > > Interestingly, the experiment proposed by Okun to answer the question
> was
> > > performed in a slightly different form by Tom Van Baak as described
> here:
> > >
> > > http://leapsecond.com/great2005/
> <https://mailtrack.io/trace/link/ea9720b84c88d315d16727ead7b409646989fb37?url=http%3A%2F%2Fleapsecond.com%2Fgreat2005%2F&userId=890907&signature=f4a4fce311e6d8be>
> > >
> > > Another link that is useful is the paper here which examines the math
> > used
> > > in the Pound-Rebka experiment and finds it is full of errors!
> > >
> > > http://milesmathis.com/pound.html
> <https://mailtrack.io/trace/link/f2b07a350d5255aa89f2aeb39716be99cc3b1746?url=http%3A%2F%2Fmilesmathis.com%2Fpound.html&userId=890907&signature=1d64708c48b2f18f>
> > >
> > > Just wondering if anyone else is aware of this apparent contradiction
> in
> > > the relativistic thinking : )
> > >
> > > Doug
> > >
> >
> > _______________________________________________
> > Physics mailing list
> > Physics at tuks.nl
> > http://mail.tuks.nl/cgi-bin/mailman/listinfo/physics
> <https://mailtrack.io/trace/link/531361df530c6cd5e1d4b6c2a397fe521779e212?url=http%3A%2F%2Fmail.tuks.nl%2Fcgi-bin%2Fmailman%2Flistinfo%2Fphysics&userId=890907&signature=538cad599694c0a2>
> >
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>
> ------------------------------
>
> Message: 4
> Date: Thu, 6 Dec 2018 08:26:12 +0100
> From: Ilja Schmelzer <ilja.schmelzer at gmail.com>
> To: General Physics and Natural Philosophy discussion list
>         <physics at tuks.nl>
> Subject: Re: [Physics] Gravitational Time Dilation and Gravitational
>         Redshift - two separate things?
> Message-ID:
>         <
> CAAKQs19p_Cv522Xww41hW2oMOOi7cQcBDoSaMs_sLjbvEZqqGQ at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> Again, my point to replace the wave with hand-waving was to make clear
> that the number of wave fronts received, if one looks at them in
> absolute background time, does not change.  What changes is the
> frequency, because it is measured with clocks, and clocks go slower,
> so that the same number of wave fronts during the same absolute time
> more means, in clock time, more wave fronts in one second, thus, a
> blue shift.
>
> And there is, nonetheless, also a relativistic mechanism for bending
> light.  First, because there is also a length contraction, but the
> main point is the change in the coordinate speed of light. That a
> change in the speed of light causes a bending can be easily seen in a
> prism.  And if one looks at GR through the Lorentz ether
> interpretation, it is clear that it is the coordinate speed which
> matters, and this coordinate speed changes.
>
> In fact, it is a simple rule:  Whenever it seems that SR/GR have
> something wrong, use the Lorentz ether interpretation to look at the
> problem.  In the Lorentz ether, the problem usually disappears.
>
> This is because the spacetime interpretation is in conflict with
> common sense intuitions, the Lorentz ether not. The equations are the
> same (see http://ilja-schmelzer.de/ether
> <https://mailtrack.io/trace/link/ea9723bfc8b135ddd298e32b5ef8d0c1623c0a9f?url=http%3A%2F%2Filja-schmelzer.de%2Fether&userId=890907&signature=7b750fbca0b42bb9>
> ) but all that is in conflict
> with common sense disappears.
>
> 2018-12-05 22:30 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
> > Hi Ilja,
> >
> >     Yes, I agree with you that " the only change in the frequency is
> > because of the clocks (which have to be used to measure the frequency of
> > the hand-waving", but the red-shift of the light can't be "the same
> thing"
> > in my mind because, as you say, from the "point of view of the background
> > time coordinate, there is no change in frequency".
> > So if there is no change in frequency from the source to the receiver,
> > there is no relativistic mechanism by which the EM wave is made to bend,
> > since the bending is supposed to be caused by the progressive change in
> > frequency through the gradient. Quite literally, for EM waves approaching
> > the earth at an angle, the portion of the wavefront closer to the earth
> > must contract compared to the portions further away, eliciting a
> > progressive bend towards the surface, and Einstein attributes this to a
> > change in frequency of the wave acted upon by the grav. gradient, which
> is
> > something physical independent of the clocks. Einstein's idea also
> creates
> > another paradox, that a receiver on the surface will receive more
> > wave-fronts than are emitted by the transmitter at altitude - if this
> were
> > true we would have a free-energy generating device!
> >
> > I think the only way out of this is to argue that it is the change in the
> > speed of light with altitude and the associated change in wavelength that
> > causes light to bend in the gradient, and frequency remains preserved.
> > Einstein himself said in 1911 that this explanation was equivalent to his
> > own (except for the energy change). Then there is only the one frequency
> > effect due to the clocks and no problem with free energy. But then the
> > black hole theory has to be a fiction.
> >
> > Doug
> >
> >
> > On Wed, Dec 5, 2018 at 3:52 PM Ilja Schmelzer <ilja.schmelzer at gmail.com>
> > wrote:
> >
> >> No, the signal will be blue-shifted only once.
> >>
> >> This can be best seen if one replaces the wave by a hand-waving person
> >> and looks at the time when the light signal of "hand up" and "hand
> >> down" arrive.
> >>
> >> If we look at this in coordinates which are natural for a stable
> >> configuration, thus, a metric of the form g_mn (x^i) dx^m dx^n with
> >> the metric coefficients depending only on the spatial coordinates, and
> >> assume the handwaving guy as well as the observer at rest, the light
> >> rays for "hands up" and for "hands down" are the same trajectories,
> >> only with a shift in the time coordinate t.
> >>
> >> Thus, from point of view of the background time coordinate, there is
> >> no change in the frequency.  Thus, the only change in the frequency is
> >> because of the clocks (which have to be used to measure the frequency
> >> of the hand-waving).   So, they are the same thing.
> >>
> >> 2018-12-04 22:12 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
> >> > Hi All,
> >> >
> >> >     This just came up in a question I had to my website - it has to do
> >> with
> >> > the Pound-Rebka experiment and whether gravitational time dilation of
> >> > clocks and gravitational redshift of EM are two different things or
> the
> >> > same thing. The problem is set out by L.B. Okun is plain language in
> an
> >> > article here: https://arxiv.org/pdf/hep-ph/0010256.pdf
> <https://mailtrack.io/trace/link/9ee49c0d721fac53fa6041522ad2d7b5f7360eec?url=https%3A%2F%2Farxiv.org%2Fpdf%2Fhep-ph%2F0010256.pdf&userId=890907&signature=b817b67371e576d8>
> >> >    The essence of it is that if you take a clock and move it from the
> >> > ground to the top of a tower, the clock should speed up in it's rate
> at
> >> the
> >> > higher altitude. If you then send an EM signal from this clock back to
> >> the
> >> > ground, Einstein says that the EM should be blue-shifted. However,
> this
> >> > would mean that the signal sent to the ground has now been
> blue-shifted
> >> > TWICE, once due to the clock speeding up,  and once due to the fall of
> >> the
> >> > EM through the gravitational gradient.
> >> > However, the Pound-Rebka experiment finds that it is blue-shifted only
> >> > once. So which effect is redundant, gravitational time dilation of
> >> > clocks
> >> > or gravitational red-shift of light? They can't be the same thing,
> >> > since
> >> > the latter is an operation performed on the EM during transit, and is
> >> > supposed to make it bend. And the former is something which happens to
> >> > clocks independent of EM signals sent between them.
> >> > Interestingly, the experiment proposed by Okun to answer the question
> >> > was
> >> > performed in a slightly different form by Tom Van Baak as described
> >> > here:
> >> >
> >> > http://leapsecond.com/great2005/
> <https://mailtrack.io/trace/link/03ebee83ce92a12016d4f4813324c16b08fb5b32?url=http%3A%2F%2Fleapsecond.com%2Fgreat2005%2F&userId=890907&signature=2cbd5c0a2319f239>
> >> >
> >> > Another link that is useful is the paper here which examines the math
> >> used
> >> > in the Pound-Rebka experiment and finds it is full of errors!
> >> >
> >> > http://milesmathis.com/pound.html
> <https://mailtrack.io/trace/link/c0ac86ae9777735f061f921d1a8b9aeb38c7c6c8?url=http%3A%2F%2Fmilesmathis.com%2Fpound.html&userId=890907&signature=7920fde7aeb68435>
> >> >
> >> > Just wondering if anyone else is aware of this apparent contradiction
> >> > in
> >> > the relativistic thinking : )
> >> >
> >> > Doug
> >> >
> >>
> >> _______________________________________________
> >> Physics mailing list
> >> Physics at tuks.nl
> >> http://mail.tuks.nl/cgi-bin/mailman/listinfo/physics
> <https://mailtrack.io/trace/link/6636bf09a296dc36df6693b364f3adf89b4c11eb?url=http%3A%2F%2Fmail.tuks.nl%2Fcgi-bin%2Fmailman%2Flistinfo%2Fphysics&userId=890907&signature=e4a3f9cee7a4ac9b>
> >>
> >
>
>
>
> ------------------------------
>
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> ------------------------------
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> End of Physics Digest, Vol 21, Issue 6
> **************************************
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