Non-recessional cosmic redshift

In article ,
Yvon Sauvageau wrote:

I start with a photon of energy h*f(0), and after n body encounters I
end up with a photon of energy h*f(n). The energy losses are the
gravitational escape energies at each encounter (ie. the energy it
takes to move the photon at infinite distance from the body).

That's not really right. To a first approximation the photon falls
towards a galaxy and gains energy, and then moves away losing
the energy it gained, leaving it with exactly the same energy.

It's no fair to count the energy lost but not the energy gained!

"Dynamical friction" comes a subtler effect: namely, the
stars in the galaxy will be pushed around a bit as the photon
moves through the galaxy, and will typically be moving a wee
bit faster at the end of the day than when they started.
Thus, energy has been transferred from the photon to the
stars in the galaxy, so the photon loses energy.

However, this effect is pathetically small, since it depends
in some way on the energy of the photon divided by the energy
of a star as computed using E = mc^2. This is a miserably
small number. So, dynamical friction of this sort is a complete
nonstarter when it comes to explaining the redshift.

In fact, the dynamical friction astronomers actually care about
arises not when a *photon* zips through a field of stars, but
when a *star* does! In this case the effect is significant.

I'm trying to convince myself that the effect is negligible, therefore
it doesn't matter if this calculation overevaluates the energy loss.

That's true, but just bear in mind that your approach overestimates
the dynamical friction by a huge enormous whopping factor, because
you're assuming the photon keeps climbing out of the galactic
gravitational fields, but neglecting that fact that it also keeps
falling in.

But the real reason I'm posting this article is not to scold
you - it's because I just read in Science magazine that people
have observed something cool that goes completely against the
ideas we've been talking about he

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

In article ,
Yvon Sauvageau wrote:

I start with a photon of energy h*f(0), and after n body encounters I
end up with a photon of energy h*f(n). The energy losses are the
gravitational escape energies at each encounter (ie. the energy it
takes to move the photon at infinite distance from the body).

That's not really right. To a first approximation the photon falls
towards a galaxy and gains energy, and then moves away losing
the energy it gained, leaving it with exactly the same energy.

It's no fair to count the energy lost but not the energy gained!

"Dynamical friction" comes a subtler effect: namely, the
stars in the galaxy will be pushed around a bit as the photon
moves through the galaxy, and will typically be moving a wee
bit faster at the end of the day than when they started.
Thus, energy has been transferred from the photon to the
stars in the galaxy, so the photon loses energy.

However, this effect is pathetically small, since it depends
in some way on the energy of the photon divided by the energy
of a star as computed using E = mc^2. This is a miserably
small number. So, dynamical friction of this sort is a complete
nonstarter when it comes to explaining the redshift.

In fact, the dynamical friction astronomers actually care about
arises not when a *photon* zips through a field of stars, but
when a *star* does! In this case the effect is significant.

I'm trying to convince myself that the effect is negligible, therefore
it doesn't matter if this calculation overevaluates the energy loss.

That's true, but just bear in mind that your approach overestimates
the dynamical friction by a huge enormous whopping factor, because
you're assuming the photon keeps climbing out of the galactic
gravitational fields, but neglecting that fact that it also keeps
falling in.

But the real reason I'm posting this article is not to scold
you - it's because I just read in Science magazine that people
have observed something cool that goes completely against the
ideas we've been talking about he

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

John Baez wrote:

Yvon Sauvageau wrote:
I start with a photon of energy h*f(0), and after n body encounters I
end up with a photon of energy h*f(n). The energy losses are the
gravitational escape energies at each encounter (ie. the energy it
takes to move the photon at infinite distance from the body).

It's no fair to count the energy lost but not the energy gained!

No, the auditors will give you a hard time for that!

"Dynamical friction" comes a subtler effect: namely, the
stars in the galaxy will be pushed around a bit as the photon
moves through the galaxy, and will typically be moving a wee
bit faster at the end of the day than when they started.
Thus, energy has been transferred from the photon to the
stars in the galaxy, so the photon loses energy.

I would have thought that the most significant effect would be the
interaction of light with atoms (and perhaps dust particles) where many
more events happen at much closer range, more than compensating for the
lesser mass of the objects encountered (Compton effect).

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

Perhaps because of continued solar system or cluster formation which
makes mass more concentrated in small volumes over time which would
affect gravitational potential?

However most light we see from distant galaxies doesn't spend very much
time in galaxies on the way here.

Ray Tomes

John Baez wrote:

Yvon Sauvageau wrote:
I start with a photon of energy h*f(0), and after n body encounters I
end up with a photon of energy h*f(n). The energy losses are the
gravitational escape energies at each encounter (ie. the energy it
takes to move the photon at infinite distance from the body).

It's no fair to count the energy lost but not the energy gained!

No, the auditors will give you a hard time for that!

"Dynamical friction" comes a subtler effect: namely, the
stars in the galaxy will be pushed around a bit as the photon
moves through the galaxy, and will typically be moving a wee
bit faster at the end of the day than when they started.
Thus, energy has been transferred from the photon to the
stars in the galaxy, so the photon loses energy.

I would have thought that the most significant effect would be the
interaction of light with atoms (and perhaps dust particles) where many
more events happen at much closer range, more than compensating for the
lesser mass of the objects encountered (Compton effect).

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

Perhaps because of continued solar system or cluster formation which
makes mass more concentrated in small volumes over time which would
affect gravitational potential?

However most light we see from distant galaxies doesn't spend very much
time in galaxies on the way here.

Ray Tomes

On Mon, 1 Sep 2003 02:51:42 +0000 (UTC), (John
Baez) wrote:
In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!
I'll let people guess why this is the case.

Sociologically, the most likely reason is errors in our cosmological
model, I would say. A model which yields no such energy increase is
more compelling, in isolation.

The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

What, "dynamical friction" on a photon? Ya gotta be kidding.

Eric

On Mon, 1 Sep 2003 02:51:42 +0000 (UTC), (John
Baez) wrote:
In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!
I'll let people guess why this is the case.

Sociologically, the most likely reason is errors in our cosmological
model, I would say. A model which yields no such energy increase is
more compelling, in isolation.

The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

What, "dynamical friction" on a photon? Ya gotta be kidding.

Eric

In article ,
Yvon Sauvageau wrote:

(John Baez) wrote in message
...

To a first approximation the photon falls
towards a galaxy and gains energy, and then moves away losing
the energy it gained, leaving it with exactly the same energy.

Your statement would be right if the cosmos was like in the textbook
examples on gravitation, where the largest mass of any pair is always
immobile with respect to the center of mass of the 2-body system, as
if there was some magic universal force that kept the largest mass of
any pair of masses immobile.

That's why I said "to a first approximation"! To a first
approximation, we can treat the stars in the galaxy as unaffected
by the photon, because they're so much heavier. When we go beyond
this first approximation, we see "dynamical friction": as the photon
moves past the stars it drags them along a little and loses some
energy. But this dynamical friction will be very small, because
a photon doesn't drag a star along very much.

It's no fair to count the energy lost but not the energy gained!

Believe it or not, I did think about that. And that's why I call my
argument a "rough estimate".

Yup. I think the word "upper bound" is a bit better.
You derived a valid upper bound; I was merely unable to
resist pointing out that this upper bound is enormously
large compared to the actual effect.

But my real point was this:

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

The dynamo effect?

Maybe that too, but I'm thinking about the Sachs-Wolf effect,
which people claim to have recently observed.

In article ,
Yvon Sauvageau wrote:

(John Baez) wrote in message
...

To a first approximation the photon falls
towards a galaxy and gains energy, and then moves away losing
the energy it gained, leaving it with exactly the same energy.

Your statement would be right if the cosmos was like in the textbook
examples on gravitation, where the largest mass of any pair is always
immobile with respect to the center of mass of the 2-body system, as
if there was some magic universal force that kept the largest mass of
any pair of masses immobile.

That's why I said "to a first approximation"! To a first
approximation, we can treat the stars in the galaxy as unaffected
by the photon, because they're so much heavier. When we go beyond
this first approximation, we see "dynamical friction": as the photon
moves past the stars it drags them along a little and loses some
energy. But this dynamical friction will be very small, because
a photon doesn't drag a star along very much.

It's no fair to count the energy lost but not the energy gained!

Believe it or not, I did think about that. And that's why I call my
argument a "rough estimate".

Yup. I think the word "upper bound" is a bit better.
You derived a valid upper bound; I was merely unable to
resist pointing out that this upper bound is enormously
large compared to the actual effect.

But my real point was this:

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

The dynamo effect?

Maybe that too, but I'm thinking about the Sachs-Wolf effect,
which people claim to have recently observed.

(John Baez) wrote in message ...
But my real point was this:

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

The dynamo effect?

Maybe that too, but I'm thinking about the Sachs-Wolf effect,
which people claim to have recently observed.

This may help,

Direct evidence found for dark energy

http://www.nature.com/nsu/030721/030721-5.html

This may confuse,


Resonant Photon Tunneling Enhancement of the van der Waals Friction

http://ojps.aip.org/getabs/servlet/G...cvips&gifs=Yes


Tunneling of friction.

Is there anything you can't tunnel?


Non-Contact Friction


http://www.aip.org/enews/physnews/2003/split/652-3.html

(John Baez) wrote in message ...
But my real point was this:

In fact, when photons go through galaxies, they come out with
MORE energy than when they went in!!!

I'll let people guess why this is the case. The point is, there's
an effect that's much more significant than dynamical friction,
and works the other way. So: what's this effect?

The dynamo effect?

Maybe that too, but I'm thinking about the Sachs-Wolf effect,
which people claim to have recently observed.

This may help,

Direct evidence found for dark energy

http://www.nature.com/nsu/030721/030721-5.html

This may confuse,


Resonant Photon Tunneling Enhancement of the van der Waals Friction

http://ojps.aip.org/getabs/servlet/G...cvips&gifs=Yes


Tunneling of friction.

Is there anything you can't tunnel?


Non-Contact Friction


http://www.aip.org/enews/physnews/2003/split/652-3.html