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science forum Guru Wannabe

Joined: 11 Sep 2005
Posts: 290

Posted: Sat Jul 15, 2006 9:35 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

Dirk Van de moortel wrote:

Give the correct equation if mine is false! But you can only parrot!

Marcel Luttgens

 Quote: Dirk Vdm
Dirk Van de moortel
science forum Guru

Joined: 01 May 2005
Posts: 3019

Posted: Sat Jul 15, 2006 10:03 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

You can't handle the meaning of the variables in equations, Marcel:
http://users.telenet.be/vdmoortel/dirk/Physics/Fumbles/DidntUseSR.html
For your own sake, try to avoid them, as long as you still can.

Dirk Vdm
Sue...
science forum Guru

Joined: 08 May 2005
Posts: 2684

Posted: Sat Jul 15, 2006 10:19 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

 Quote: Equation 14 should here be written in terms of the shaft depth! Perhaps a true GR specialist could do this.

Perhaps they anticipated it might be used on another
planet where the shaft depth would be meaningless.

 Quote: It is in terms of gravitational potential so would predict the lowest frequency at the surface then increasing as the clock either moved up or down. That is consistant with free pendulms, long know to decrease in frequency when moved up or down from the surface. As for your equation above, Nu1 should equal Nu2. Look at my equation: the shift is given by (GMe/2Re^3c^2) * (Re^2-d^2) Only if d = Re is Nu2 equal to Nu1 (the depth of the shaft is 0). If d = 0 (the receiver is at the Earth's center), the shift becomes GMe/2Re*c^2. This shift should rather easily be obtained with GR.

I would rather review the arithmetic for the bellhop paradox
changes frequency absent a change in path length.

Are you saying if the paper substitutes your equation
for the one they used then it will make the paper wrong?
If so then I agree with you because the paper appears
correct as it is.... to degee of showing the spacetime
interval tau instead of time, a detail many writers overlook.

Sue...

 Quote: ...unless you have a mechanism to create or destroy the news of events as it is propagated. ????? Marcel Luttgens Maybe that is what is happening on a noisy satellite feed when the announcer freezes for a few seconds? ) Sue... Marcel Luttgens
Henri Wilson
science forum Guru

Joined: 08 May 2005
Posts: 3381

Posted: Sat Jul 15, 2006 11:26 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

On 13 Jul 2006 16:20:27 -0700, mluttgens@wanadoo.fr wrote:

 Quote: PD wrote: mluttgens@wanadoo.fr wrote: PD wrote: Incidentally, have you realised that the slowing of light due to gravity is one

of the main reasons for the observed galactic redshift?

On average, starlight comes to us predominantly from regions close to galatic
centres. We lie well away from the centre of Milky way. So average light loses
more energy escaping its galactic source than it gains when falling into the
outskirts our galaxy. That applies to light coming from all directions.

So we should expect to see far more redshifted light than blue.....which is
what happens.
The relationship with distance is due to other 'factors' such as light's
slowing as it travels and interaction with other light and 'fields'.

HW.
www.users.bigpond.com/hewn/index.htm

Appropriate message snipping is considerate and painless.
science forum Guru Wannabe

Joined: 11 Sep 2005
Posts: 290

Posted: Sun Jul 16, 2006 8:27 am    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

Sue... wrote:

"Perhaps they anticipated it might be used on another
planet where the shaft depth would be meaningless."

Ha Ha !

 Quote: It is in terms of gravitational potential so would predict the lowest frequency at the surface then increasing as the clock either moved up or down. That is consistant with free pendulms, long know to decrease in frequency when moved up or down from the surface. As for your equation above, Nu1 should equal Nu2. Look at my equation: the shift is given by (GMe/2Re^3c^2) * (Re^2-d^2) Only if d = Re is Nu2 equal to Nu1 (the depth of the shaft is 0). If d = 0 (the receiver is at the Earth's center), the shift becomes GMe/2Re*c^2. This shift should rather easily be obtained with GR. I would rather review the arithmetic for the bellhop paradox again than your equations after your statement that light changes frequency absent a change in path length.

"Are you saying if the paper substitutes your equation
or the one they used then it will make the paper wrong?"

As long as their equation 14 is not written in terms of Me, Re and d,
I prefer to wait and see.

A nicer form of the "shaft" shift formula is
shift = GMe/2Rec^2 * (1-d^2/Re^2),
where d is the distance between the bottom of the shaft and the
Earth's center.
The shift could of course be expressed in terms of the
shaft depth = Re-d. Replacing d by Re-depth, one gets
shift = GMe/2Rec^2 * (1-(Re-depth)^2/Re^2)

If the depth = Re, one is left with shift = GMe/2Rec^2 (1)
Let's remember that the signal is sent from the Earth's surface
to the bottom of the shaft.

Notice that a signal emitted at infinity towards the Earth's surface
would be observed to be shifted by GMe/Rec^2 (also according to GR).
The fact that this shift is twice the "shaft" shift (1) must be
more than a coincidence!

Marcel Luttgens

 Quote: If so then I agree with you because the paper appears correct as it is.... to degee of showing the spacetime interval tau instead of time, a detail many writers overlook. Sue... ...unless you have a mechanism to create or destroy the news of events as it is propagated. ????? Marcel Luttgens Maybe that is what is happening on a noisy satellite feed when the announcer freezes for a few seconds? ) Sue... Marcel Luttgens
Sue...
science forum Guru

Joined: 08 May 2005
Posts: 2684

Posted: Sun Jul 16, 2006 12:07 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

You have us totally confused. You posted Okun's paper
that explains how to avoid the causality violating interpretation.

But now you are arguing on both sides of the issue and
stating propagation effects that violate causality. Perhaps
you should re-read the paper, then attack someone elses

Equation 14 looks reasonable and it appers in full
conformity with Okun's recommendations.
http://arxiv.org/abs/gr-qc/9606079

Sue...
science forum Guru Wannabe

Joined: 11 Sep 2005
Posts: 290

Posted: Sun Jul 16, 2006 4:45 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

Sue... wrote:

"For a freely falling absorber, a signal emitted from the ground
would appear *Doppler blue shifted* by gH/c^2 if it were not
*beforehand* red shifted by gH/c^2 by "the gravitational attraction
of the massive body".

Because of the Doppler effect, one has to accept that the energy and
frequency of the propagating photon change with height, and that clocks

don't run the faster the higher they are located in the potential."

Otoh, I gave a formula for the shift of a signal sent from the Earth's
surface to the bottom of a shaft.

Marcel Luttgens
Sue...
science forum Guru

Joined: 08 May 2005
Posts: 2684

Posted: Sun Jul 16, 2006 5:20 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

I have search several words in inside your quote markes and
can not find that in Okun's paper 9907017. What page are
did you find it on ?

 Quote: Because of the Doppler effect, one has to accept that the energy and frequency of the propagating photon change with height, and that clocks don't run the faster the higher they are located in the potential."

The Dopper effect doesn't have any thing to do with energy..
In Mossbauer experiments the light is Doppler shifted so
it will match the nuclear resonance of the atom.

Photons don't propagte.
http://nobelprize.org/physics/articles/ekspong/index.html

 Quote: Otoh, I gave a formula for the shift of a signal sent from the Earth's surface to the bottom of a shaft. I don't see any contradiction.

Sue...

 Quote: Marcel Luttgens
Phineas T Puddleduck
science forum Guru

Joined: 01 Jun 2006
Posts: 759

Posted: Sun Jul 16, 2006 6:08 pm    Post subject: Re: Marcel Luttgens - s**t Eater

mother <l3jklr94jt594j@comicmail.co.uk> wrote:

 Quote: dda1 wrote: mluttgens@wanadoo.fr wrote: snipped, the m**********r doesn't understand the Pound Rebka experiment Hey, the food is pretty good in your country, why do you persist in eating s**t breakfast, lunch and dinner? what about not changin tha foken subject lines yo stooped foken nazimothofaka

*PLONK*

Stupid cretin

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science forum Guru Wannabe

Joined: 11 Sep 2005
Posts: 290

Posted: Sun Jul 16, 2006 9:05 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

Sue... wrote:

Look at the excerpts in my first message.

 Quote: Because of the Doppler effect, one has to accept that the energy and frequency of the propagating photon change with height, and that clocks don't run the faster the higher they are located in the potential." The Dopper effect doesn't have any thing to do with energy.. In Mossbauer experiments the light is Doppler shifted so it will match the nuclear resonance of the atom.

Please refer to my first message. I will not repeat the same arguments
Quibbling is pleasant for the quibbler.

Show me instead how you derive the"shaft" shift formula
shift = GMe/2Rec^2 * (1-d^2/Re^2)
from your pet GR equation 14.

Marcel Luttgens

 Quote: Photons don't propagte. http://nobelprize.org/physics/articles/ekspong/index.html Otoh, I gave a formula for the shift of a signal sent from the Earth's surface to the bottom of a shaft. I don't see any contradiction. There seems to be several contradictions in your account of what others have written and the copies I have downloaded. Sue... Marcel Luttgens
Dirk Van de moortel
science forum Guru

Joined: 01 May 2005
Posts: 3019

Posted: Sun Jul 16, 2006 9:41 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

[snip]

 Quote: Quibbling is pleasant for the quibbler.

And two idiots quibbling can be fun to watch
Thanks, guys.

Dirk Vdm
Sue...
science forum Guru

Joined: 08 May 2005
Posts: 2684

Posted: Sun Jul 16, 2006 10:40 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

 Quote: Einstein interpretation of gravitational redshift is misleading Exerpt snipped Let's consider that photons loose energy as they overcome the gravitational attraction of the Earth:

That is absurd.
http://nobelprize.org/physics/articles/ekspong/index.html

 Quote: A light signal of frequency Nu1 is emitted by an atom at rest on the surface of the earth. The energy of a photon is thus E1 = hNu1 and its "mass" m = E1/c^2 = hNu1/c^2.

Where do you find angular momentum equivalent to mass ?

 Quote: At a height H, i.e. at a distance d = Rearth + H from the Earth's center, the frequency of the received signal is Nu2, hence the photon's energy is E2 = hNu2. Its potential energy is Ep = m * gm * H, where gm = GMearth/(Rearth*d). From E2 = E1 - Ep, one gets hNu2 = hNu1 - hNu1/c^2 * GMearth/(Rearth*d) * (d-Rearth) Nu2 = Nu1 * (1 - GMearth/c^2 * (1/Rearth - 1/d) The corresponding shift Nu2/Nu1 - 1 = -GMearth/c^2 * (1/Rearth - 1/d), which is a redshift. The same shift would be obtained using GR.

I see little resemblence to your computation
See equation 12, fully comliant with Okuns recommendations.
http://arxiv.org/abs/gr-qc/9606079

 Quote: To simplify, one could consider, like the authors of the paper did, that g is approximately constant when H is small. Then Ep = m * g * H = hNu1/c^2 * g * H (where g = GMearth/Rearth^2) hNu2 = hNu1 - hNu1/c^2 * g * H = hNu1 (1 - g*H/c^2) The shift then reduces to -g*H/c^2. It is easy to show that the interpretation according to which "clocks run the faster the higher they are located in the potential, whereas the energy and frequency of the propagating photon do not change with height" is wrong. It suffices to consider the case when the signal receiver is freely falling. Excerpt:snipped

Yes... it is easy to do that. The thing which is hard is learing
some basic electromagnetic propagation so your postings don't
look like something you saw in a billard parlor.
http://farside.ph.utexas.edu/teaching.html
http://web.mit.edu/8.02t/www/802TEAL3D/teal_tour.htm
http://en.wikipedia.org/wiki/Mossbauer_effect

 Quote: In such situation, for the freely falling absorber, the signal emitted from the ground would appear *Doppler blue shifted* by gH/c^2 if it were not *beforehand* red shifted by gH/c^2 by "the gravitational attraction of the massive body". Iow, for the absorber, the signal is not shifted at all. This is a logical proof that the signal is red shifted when it leaves the emitter. This proof falsifies Einstein's view:

....and your assumption of absurd light propagation

Sue...

 Quote: Excerpt snipped Marcel Luttgens
John C. Polasek
science forum Guru

Joined: 30 Apr 2005
Posts: 321

Posted: Sun Jul 16, 2006 11:48 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

On 15 Jul 2006 00:41:34 -0700, mluttgens@wanadoo.fr wrote:

 Quote: Sue... wrote: mluttgens@wanadoo.fr wrote: As the receiver is moving relatively to the source, why doesn't he observe a blue shift due to the Doppler effect, instead of no shift at all? The Mossbauer 'receiver' is extremely narrow due to the high Q of the atomic oscillator. It only observes (absorbs) light which is of the right frequency and phase to permit an efficient transition to a permissible energy level. A wide band receiver will intercept the transitions at a higher rate due to the closing motion, just as you have described. Sue... Thank you. Only crackpots would stick to the explanation according to which "clocks which run the faster the higher they are located in the potential, whereas the energy and frequency of the propagating photon do not change with height."

That should be "do not change with height AFTER EMISSION". Naturally a
faster clock has higher frequency, and the higher frequency does not
change after it is emitted.

 Quote: But, nevertheless, most GRists will probably not openly recognize that such explanation is "misleading". Marcel Luttgens

John Polasek
John C. Polasek
science forum Guru

Joined: 30 Apr 2005
Posts: 321

Posted: Sun Jul 16, 2006 11:56 pm    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

On 15 Jul 2006 10:56:47 -0700, mluttgens@wanadoo.fr wrote:

 Quote: Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: As the receiver is moving relatively to the source, why doesn't he observe a blue shift due to the Doppler effect, instead of no shift at all? The Mossbauer 'receiver' is extremely narrow due to the high Q of the atomic oscillator. It only observes (absorbs) light which is of the right frequency and phase to permit an efficient transition to a permissible energy level. A wide band receiver will intercept the transitions at a higher rate due to the closing motion, just as you have described. Sue... Thank you. Only crackpots would stick to the explanation according to which "clocks which run the faster the higher they are located in the potential, whereas the energy and frequency of the propagating photon do not change with height." But, nevertheless, most GRists will probably not openly recognize that such explanation is "misleading". Marcel Luttgens LOL I am looking for a Pound-Rebka-Snider experiment down a mine shaft. I think that would clear up a lot of the misunderstanding but so far I haven't found one. Either my research skills are getting rusty or graduate students have a softer life these days. Sue... You wrote: "I am looking for a Pound-Rebka-Snider experiment down a mine shaft. I think that would clear up a lot of the misunderstanding but so far I haven't found one."

You could do with some study. You probably do not realize that the
gravity at the bottom of the mine shaft is lower than at the surface.
So it's not a Pound Rebka experiment.
Yes, g tapers from 0 at center to gnormal at the surface.

 Quote: In the meantime, you could content yourself with the formula easily obtained by using the potential energy of the photons: Nu1 is the frequency of the signal sent to the bottom of the shaft. Nu2 is the frequency of the signal received at the bottom. d is the distance of the bottom of the shaft to the Earth's center. Me and Re are respectively the mass and the radius of the Earth. The shift Nu2/Nu1 - 1 = (GMe/2Re^3c^2) * (Re^2-d^2)

(Re^2-d^2) looks like bad mathematics. Are Re and d at right angles?

 Quote: If GR doesn't get the same formula, it is false. Marcel Luttgens John Polasek
The Ghost In The Machine1
science forum Guru

Joined: 25 Mar 2005
Posts: 1551

Posted: Mon Jul 17, 2006 2:00 am    Post subject: Re: Einstein interpretation of gravitational redshift is misleading

On Sun, 16 Jul 2006 21:41:41 +0000, Dirk Van de moortel wrote:

 Quote: mluttgens@wanadoo.fr> wrote in message news:1153083953.338245.290050@35g2000cwc.googlegroups.com... Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: Sue... wrote: mluttgens@wanadoo.fr wrote: [snip] Quibbling is pleasant for the quibbler. And two idiots quibbling can be fun to watch Thanks, guys. Dirk Vdm

Quibble, quibble, goo and dribble,
Vitriol and lots of muddle...

:-)

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