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Groups > sci.physics > #519359 > unrolled thread

Relativistic Radio

Started byFabian Russell <root@localhost.localdomain>
First post2015-09-06 20:21 +0000
Last post2015-09-14 09:31 -0500
Articles 20 on this page of 100 — 11 participants

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Contents

  Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-06 20:21 +0000
    Re: Relativistic Radio Double-A <double-a3@hush.com> - 2015-09-06 14:34 -0700
      Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-06 21:47 +0000
    Re: Relativistic Radio pcardinale@volcanomail.com - 2015-09-06 17:36 -0700
      Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-07 01:56 +0000
        Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-07 07:15 +0200
          Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-07 05:44 +0000
            Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-07 08:50 +0200
        Re: Relativistic Radio pcardinale@volcanomail.com - 2015-09-07 15:16 -0700
        Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-08 10:04 -0500
          Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-08 16:59 +0000
            Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-08 12:41 -0500
              Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-08 18:24 +0000
            Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-08 21:22 +0200
          Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-08 17:43 +0000
            Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-08 12:47 -0500
              Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-08 19:26 +0000
          Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-10 01:58 -0700
            Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-10 19:16 +0200
              Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-10 19:42 +0200
                Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-11 00:53 -0700
                  Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-11 06:07 -0700
                  Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-11 15:08 +0200
                    Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-11 15:28 +0200
                    Re: Relativistic Radio Mahipal <mahipal7638@gmail.com> - 2015-09-11 06:31 -0700
                      Re: Relativistic Radio "Phony McNymster" <invalid@example.com> - 2015-09-11 07:42 -0700
                        Re: Relativistic Radio Mahipal <mahipal7638@gmail.com> - 2015-09-11 07:59 -0700
                    Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-11 07:16 -0700
                      Re: Relativistic Radio Sam Wormley <swormley1@gmail.com> - 2015-09-11 09:41 -0500
                      Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-11 09:49 -0500
                        Re: Relativistic Radio Fabian Russell <root@localhost.localdomain> - 2015-09-11 18:18 +0000
                          Re: Relativistic Radio noTthaTguY <abu.kuanysh05@gmail.com> - 2015-09-11 11:24 -0700
                          Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-12 11:20 +0200
                        Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-12 06:21 -0700
                          Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 02:04 +0200
                            Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-13 00:07 -0700
                              Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 09:22 +0200
                                Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 09:59 +0200
                                Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-13 03:44 -0700
                                  Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-14 07:33 +0200
                                    Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-14 07:49 +0200
                                      Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 01:07 -0700
                                        Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 10:40 +0200
                                          Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 03:40 -0700
                                            Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 13:19 +0200
                                              Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 04:55 -0700
                                                Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 15:01 +0200
                                                  Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 16:36 +0200
                                                    Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 12:18 -0700
                                                      Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 08:29 +0200
                                                        Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 02:41 -0700
                                                          Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 12:11 +0200
                                                            Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 06:06 -0700
                                                              Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 15:40 +0200
                                                            Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 06:06 -0700
                                                              Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 15:59 +0200
                                                                Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 09:39 -0700
                                                                  Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 18:47 +0200
                                                                    Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 10:10 -0700
                                                                      Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 19:57 +0200
                                                                        Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 11:14 -0700
                                                                          Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 20:23 +0200
                                                                            Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 20:31 +0200
                                                                              Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 12:21 -0700
                                                                          Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-15 13:30 -0500
                                    Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 00:57 -0700
                                      Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 14:50 +0200
                                        Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 12:57 -0700
                                          Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 08:37 +0200
                                            Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 03:06 -0700
                                              Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 13:10 +0200
                                                Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 13:15 +0200
                                                Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-15 06:43 -0700
                                                  Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 16:11 +0200
                                                    Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 18:26 +0200
                                                      Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 18:35 +0200
                                                  Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 16:44 +0200
                                  Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-14 08:15 +0200
                                    Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-14 08:44 +0200
                      Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-11 17:38 +0200
                        Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-11 18:00 +0200
                        Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-11 11:22 -0500
                          Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-12 12:29 -0700
                            Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 01:16 +0200
                              Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-12 23:09 -0700
                                Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 08:35 +0200
                                  Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 08:44 +0200
                                  Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-12 23:50 -0700
                                    Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 09:14 +0200
                                      Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-13 05:24 -0700
                                        Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-14 07:35 +0200
                                          Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 01:01 -0700
                                            Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-14 10:39 +0200
                                    Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-14 09:34 -0500
                                      Re: Relativistic Radio jaymoseley@hotmail.com - 2015-09-14 12:31 -0700
                                        Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-15 08:53 +0200
                                          Re: Relativistic Radio Poutnik <Poutnik4NNTP@gmail.com> - 2015-09-15 10:22 +0200
                                  Re: Relativistic Radio Poutnik <poutnik4nntp@gmail.com> - 2015-09-13 09:08 +0200
                                Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-14 09:32 -0500
                            Re: Relativistic Radio Odd Bodkin <bodkinodd@gmail.com> - 2015-09-14 09:31 -0500

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#519359 — Relativistic Radio

FromFabian Russell <root@localhost.localdomain>
Date2015-09-06 20:21 +0000
SubjectRelativistic Radio
Message-ID<pan.2015.09.06.20.21.35@localhost.localdomain>
Think you're knowledgeable about modern physics?  Well then,
answer this one:

I am driving along in my relativistic automobile.  A radio station
broadcasts at a frequency X.  I turn in the direction of the
transmitter and hit the accelerator to bring me to a velocity
of 0.6c.  The frequency I receive is now 2X.

But what about the energy?  The energy of the EM waves as I perceive
them has now increased, but in the transmitter frame the energy remains
the same.  What is happening?

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#519380

FromDouble-A <double-a3@hush.com>
Date2015-09-06 14:34 -0700
Message-ID<7e6db3df-7274-402c-b207-e0744eab2371@googlegroups.com>
In reply to#519359
On Sunday, September 6, 2015 at 1:22:14 PM UTC-7, Fabian Russell wrote:
> Think you're knowledgeable about modern physics?  Well then,
> answer this one:
> 
> I am driving along in my relativistic automobile.  A radio station
> broadcasts at a frequency X.  I turn in the direction of the
> transmitter and hit the accelerator to bring me to a velocity
> of 0.6c.  The frequency I receive is now 2X.
> 
> But what about the energy?  The energy of the EM waves as I perceive
> them has now increased, but in the transmitter frame the energy remains
> the same.  What is happening?


So?  Chestnuts falling from trees and hitting your windshield would appear to have increased energy too. 

Double-A

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#519388

FromFabian Russell <root@localhost.localdomain>
Date2015-09-06 21:47 +0000
Message-ID<pan.2015.09.06.21.47.53@localhost.localdomain>
In reply to#519380
On Sun, 06 Sep 2015 14:34:18 -0700, Double-A wrote:

> 
> [snip retarded drool]
>

Your brains are exempt from relativity.  All observers will agree on
you having zero intelligence.

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#519439

Frompcardinale@volcanomail.com
Date2015-09-06 17:36 -0700
Message-ID<a4bc4378-ad92-4b35-8d2a-c2e148a12245@googlegroups.com>
In reply to#519359
On Sunday, September 6, 2015 at 1:22:14 PM UTC-7, Fabian Russell wrote:
> Think you're knowledgeable about modern physics?  Well then,
> answer this one:
> 
> I am driving along in my relativistic automobile.  A radio station
> broadcasts at a frequency X.  I turn in the direction of the
> transmitter and hit the accelerator to bring me to a velocity
> of 0.6c.  The frequency I receive is now 2X.
> 
> But what about the energy?  The energy of the EM waves as I perceive
> them has now increased, but in the transmitter frame the energy remains
> the same.  What is happening?

Energy is frame dependent.  Physics 101.

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#519460

FromFabian Russell <root@localhost.localdomain>
Date2015-09-07 01:56 +0000
Message-ID<pan.2015.09.07.01.56.48@localhost.localdomain>
In reply to#519439
On Sun, 06 Sep 2015 17:36:00 -0700, pcardinale wrote:

> 
> Energy is frame dependent.  Physics 101.
>

Oh really.

The number of photons emitted in each frame is the same.
In principle, all could be captured in moving frames and
thus total energy conservation would be violated.

Explain what is happening.

Or can we get something for nothing.



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#519480

FromPoutnik <poutnik4nntp@gmail.com>
Date2015-09-07 07:15 +0200
Message-ID<msj6dn$v4e$1@dont-email.me>
In reply to#519460
Dne 07/09/2015 v 03:56 Fabian Russell napsal(a):
> On Sun, 06 Sep 2015 17:36:00 -0700, pcardinale wrote:
> 
>>
>> Energy is frame dependent.  Physics 101.
>>
> 
> Oh really.

Oh really.
> 
> The number of photons emitted in each frame is the same.
> In principle, all could be captured in moving frames and
> thus total energy conservation would be violated.
> 
> Explain what is happening.

In different frames different energy is used to produce the photons,
thus the frame total energy conservation is not violated.

Note that different frames have different total energy values.
> 
> Or can we get something for nothing.
> 
No, we cannot.


-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes great men humble, but small men arrogant.

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#519481

FromFabian Russell <root@localhost.localdomain>
Date2015-09-07 05:44 +0000
Message-ID<pan.2015.09.07.05.44.51@localhost.localdomain>
In reply to#519480
On Mon, 07 Sep 2015 07:15:17 +0200, Poutnik wrote:

> 
> In different frames different energy is used to produce the photons,
> thus the frame total energy conservation is not violated.
> 

Total energy is the same.  The intensity, however, and the antenna
pattern are subject to transformation.  The moving observer sees
a different intensity of radiation and a different radiation pattern.

If a standard dipole antenna pattern is present in the stationary frame
the moving frame observes the following pattern:

http://s12.postimg.org/qq52njtel/doppler.png

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#519487

FromPoutnik <poutnik4nntp@gmail.com>
Date2015-09-07 08:50 +0200
Message-ID<msjbvt$efc$1@dont-email.me>
In reply to#519481
Dne 07/09/2015 v 07:44 Fabian Russell napsal(a):
> On Mon, 07 Sep 2015 07:15:17 +0200, Poutnik wrote:
> 
>>
>> In different frames different energy is used to produce the photons,
>> thus the frame total energy conservation is not violated.
>>
> 
> Total energy is the same. 

Total invariant energy is the same.
But not all frame energy is invariant energy.

Frame energies differ in total kinetic energy,
as each frame counts zero kinetic energy for different state.

Also, one must count
what energy the moving transmitter puts in, not standing one.


-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes great men humble, but small men arrogant.

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#519632

Frompcardinale@volcanomail.com
Date2015-09-07 15:16 -0700
Message-ID<c86fea51-2aa4-4501-83c7-ef6b4e5e54f4@googlegroups.com>
In reply to#519460
On Sunday, September 6, 2015 at 6:57:06 PM UTC-7, Fabian Russell wrote:
> On Sun, 06 Sep 2015 17:36:00 -0700, pcardinale wrote:
> 
> > 
> > Energy is frame dependent.  Physics 101.
> >
> 
> Oh really.
> 

Yes, really.

> The number of photons emitted in each frame is the same.

Yes.

> In principle, all could be captured in moving frames and
> thus total energy conservation would be violated.
>

No.  Total energy is conserved.  But the value is different in different frames.

> Explain what is happening.
>

Energy is frame dependent.  Physics 101.

> Or can we get something for nothing.

No.

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#519749

FromOdd Bodkin <bodkinodd@gmail.com>
Date2015-09-08 10:04 -0500
Message-ID<msmtd8$h1k$2@speranza.aioe.org>
In reply to#519460
On 9/6/2015 8:56 PM, Fabian Russell wrote:
> On Sun, 06 Sep 2015 17:36:00 -0700, pcardinale wrote:
>
>>
>> Energy is frame dependent.  Physics 101.
>>
>
> Oh really.
>
> The number of photons emitted in each frame is the same.
> In principle, all could be captured in moving frames and
> thus total energy conservation would be violated.

Why do you think energy conservation would be violated?
Energy conservation doesn't say that the energy is the same in both frames.

A car in the road frame has an energy of 450,000 J. The very same car as 
viewed in the rest frame of another car in the opposite lane has 
1,800,000 J. This is classical mechanics.

>
> Explain what is happening.
>
> Or can we get something for nothing.
>
>
>
>


-- 
Odd Bodkin --- maker of fine toys, tools, tables

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#519770

FromFabian Russell <root@localhost.localdomain>
Date2015-09-08 16:59 +0000
Message-ID<pan.2015.09.08.16.59.50@localhost.localdomain>
In reply to#519749
On Tue, 08 Sep 2015 10:04:10 -0500, Odd Bodkin wrote:

> 
> Why do you think energy conservation would be violated?
> Energy conservation doesn't say that the energy is the same in both frames.
> 
> This is classical mechanics.
> 

We're not talking mechanics.  We're talking electromagnetics.

Consider that an atomic transition in the rest frame produces
a photon.  Will an observer in the moving frame, who senses
an increased photon energy, also see different energy levels
in the atom?

Consider a (tiny) transmitter, in the rest frame, powered by a battery
that contains one mole of reactant.  Does the observer in the moving
frame see a greater energy (potential) within that one mole?

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#519775

FromOdd Bodkin <bodkinodd@gmail.com>
Date2015-09-08 12:41 -0500
Message-ID<msn6l2$7cr$2@speranza.aioe.org>
In reply to#519770
On 9/8/2015 11:59 AM, Fabian Russell wrote:
> On Tue, 08 Sep 2015 10:04:10 -0500, Odd Bodkin wrote:
>
>>
>> Why do you think energy conservation would be violated?
>> Energy conservation doesn't say that the energy is the same in both frames.
>>
>> This is classical mechanics.
>>
>
> We're not talking mechanics.  We're talking electromagnetics.

I'm pretty sure the frame dependence of energy conservation doesn't 
depend on whether it's classical mechanics or electromagnetics.

>
> Consider that an atomic transition in the rest frame produces
> a photon.  Will an observer in the moving frame, who senses
> an increased photon energy, also see different energy levels
> in the atom?

Yes, indeed.



-- 
Odd Bodkin --- maker of fine toys, tools, tables

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#519780

FromFabian Russell <root@localhost.localdomain>
Date2015-09-08 18:24 +0000
Message-ID<pan.2015.09.08.18.24.10@localhost.localdomain>
In reply to#519775
On Tue, 08 Sep 2015 12:41:56 -0500, Odd Bodkin wrote:

> 
> I'm pretty sure the frame dependence of energy conservation doesn't 
> depend on whether it's classical mechanics or electromagnetics.
> 

This problem is actually a statement of synchrotron radiation.

In synchrotron radiation, the energy produced in the particle
frame is utilized in the laboratory frame.  If the lab frame
sees a higher frequency, with a concomitant higher total energy, 
then the energy used to produce the radiation in the particle
frame will be multiplied and expended in the lab frame.
Hence we get something for nothing.

http://www.cv.nrao.edu/course/astr534/SynchrotronPower.html

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#519793

FromPoutnik <poutnik4nntp@gmail.com>
Date2015-09-08 21:22 +0200
Message-ID<msnce1$11l$1@dont-email.me>
In reply to#519770
Dne 08/09/2015 v 18:59 Fabian Russell napsal(a):

> 
> Consider that an atomic transition in the rest frame produces
> a photon.  Will an observer in the moving frame, who senses
> an increased photon energy, also see different energy levels
> in the atom?
> 

An atom with an excited electron has higher mass dm = dE/c^2
than an atom at a base level. Therefore the former
has at given velocity higher kinetic energy than the latter.

Emission by moving atom provides additional energy
equal to difference of the kinetic energies of the different masses.

Furthermore, there is redistribution of momentum, aside of energy.

An approaching atom decelerates while emitting a photon toward you.
Decreased kinetic energy of the atom  adds to the photon energy.

A departing atom accelerates while emitting a photon toward you.
Increased kinetic energy of the atom
subtracts from to the photon energy.

These 3 effects increase with increasing atom speed.

-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes great men humble, but small men arrogant.

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#519776

FromFabian Russell <root@localhost.localdomain>
Date2015-09-08 17:43 +0000
Message-ID<pan.2015.09.08.17.43.47@localhost.localdomain>
In reply to#519749
On Tue, 08 Sep 2015 10:04:10 -0500, Odd Bodkin wrote:

> 
> Why do you think energy conservation would be violated?
> Energy conservation doesn't say that the energy is the same in both frames.
> 
> This is classical mechanics.
> 

I cannot find much on the 'net to back up my claims.  All web sites just
rehash the standard textbook argument on mechanics.

However, although not ideal, here is an excerpt from the "Alice in
Physics" site:

http://www.aliceinphysics.com/publications/doppler/en/doppler.html

"We clearly see that any kind of differences that occurred on the wavelength
DOES NOT CHANGE THE TOTAL ENERGY OF THE ELECTROMAGNETIC WAVE (the energy that
is between two peak points). Only the energy of the electromagnetic wave does
take place in a larger (Redshift) or a more narrow distance (Blueshift) on
the field of the spaceship. Instead of this, we can say that the frequency
of the electromagnetic wave changes. In one respect, Doppler Effect is the law
of conservation of energy between electromagnetic wave and its target.

"As a result of change of the wavelength, the amount of energy that reaches
to the spaceship in unit time, changes. This situation is sensed and measured
as frequency change of the electromagnetic wave."

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#519777

FromOdd Bodkin <bodkinodd@gmail.com>
Date2015-09-08 12:47 -0500
Message-ID<msn6vk$9ce$1@speranza.aioe.org>
In reply to#519776
On 9/8/2015 12:43 PM, Fabian Russell wrote:
> On Tue, 08 Sep 2015 10:04:10 -0500, Odd Bodkin wrote:
>
>> >
>> >Why do you think energy conservation would be violated?
>> >Energy conservation doesn't say that the energy is the same in both frames.
>> >
>> >This is classical mechanics.
>> >
> I cannot find much on the 'net to back up my claims.  All web sites just
> rehash the standard textbook argument on mechanics.

Why are you not looking in books, which talk about the frame dependence 
of energy in electromagnetism?

-- 
Odd Bodkin --- maker of fine toys, tools, tables

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#519795

FromFabian Russell <root@localhost.localdomain>
Date2015-09-08 19:26 +0000
Message-ID<pan.2015.09.08.19.24.49@localhost.localdomain>
In reply to#519777
On Tue, 08 Sep 2015 12:47:34 -0500, Odd Bodkin wrote:

> 
> Why are you not looking in books, which talk about the frame dependence 
> of energy in electromagnetism?
>

Here's a nice on-line text-book:

http://farside.ph.utexas.edu/teaching/em/lectures/node106.html

Looking at equation #1649 (in node130) we see a relativistic
generalization of Larmor's formula, which is valid in all reference
frames.

In equation #1676 (in node133) we find the differential dependence
of power on solid angle.

The gist is that the radiation angular distribution differs between
the two frames but the *integral* of dPower/dAangle over either
angular distribution gives the same power.

http://s12.postimg.org/qq52njtel/doppler.png

At least that is my understanding.  If I am incorrect, then
where is the error?

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#520089

Fromjaymoseley@hotmail.com
Date2015-09-10 01:58 -0700
Message-ID<c0c2160b-597f-4dbb-ac76-55b06d684cdd@googlegroups.com>
In reply to#519749
Odd wrote...
>> The number of photons emitted in each frame is the same. 
>> In principle, all could be captured in moving frames and 
>> thus total energy conservation would be violated.

>Why do you think energy conservation would be violated?
> Energy conservation doesn't say that the energy is the same in both frames.

Interesting argument he has. But it seems inadvertantly to be a good argument
against the the concept of photons and for a wave only model of emr.

For example: a source emits 10 photons at an energy x per photon. (total energy
10x) Observor who doesnt move relative to source gets 10 photons (10x) of energy. 
So far no free energy.
But if the observor moves towards source at speed where observed wavelength halves 
and energy per photon doubles then if its still 10 photons, the total energy 
observed doubles. I think thats fabians argument. Something for nothing. 

But if emr is modeled as waves only quantized at detectors as I have often argued,
then there is no "something for nothing"....
Now take the same example ...In a certain time period the source emits a burst of 
energy of 10x amount in wave only emr. If the observor isnt moving they see 
10x energy,  quantized into what appears to be 10 'photons' worth at their detector. 
But if they move towards the source at such a speed that the observed wavelength 
halves then the observor sees the same burst 10x of emr but in half the time. 
The incoming blueshifted emr is double the energy per second, but because its 
only observed for half the time, the total observed energy is the same as for when 
the observor wasnt moving relative to the source. 
At the detector this higher frequency , shorter wavelength emr is 
qauntized into only 5 'photons'. (But importantly...5 higher energy 'photons'.)

No something for nothing in a wave only model of light.

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#520114

FromPoutnik <Poutnik4NNTP@gmail.com>
Date2015-09-10 19:16 +0200
Message-ID<mssdpr$lt6$1@dont-email.me>
In reply to#520089
On 09/10/2015 10:58 AM, jaymoseley@hotmail.com wrote:
> For example: a source emits 10 photons at an energy x per photon. (total energy
> 10x) Observor who doesnt move relative to source gets 10 photons (10x) of energy. 
> So far no free energy.
> But if the observor moves towards source at speed where observed wavelength halves 
> and energy per photon doubles then if its still 10 photons, the total energy 
> observed doubles. I think thats fabians argument. Something for nothing. 

Not for nothing.

In the frame where the source is moving,
the source does not provide the same energy to the photon
as if is in the rest.

- quantum energy level differences slightly increase for moving source,
  as they belong to different source masses
  ( and therefore different   kinetic energies at the same speed.

- additional energy is added/subtracted to/from a photon
    in case of decelerating approaching
    or accelerating departing source.


-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes a great man humble, but a small man arrogant.

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#520116

FromPoutnik <Poutnik4NNTP@gmail.com>
Date2015-09-10 19:42 +0200
Message-ID<mssfb3$soq$1@dont-email.me>
In reply to#520114
On 09/10/2015 07:16 PM, Poutnik wrote:
> - additional energy is added/subtracted to/from a photon
>     in case of decelerating approaching
>     or accelerating departing source.

As if a source is moving toward you,
emission of a photon toward you decelerates it
and the energy is added to the photon energy.

OTOH, if the source is moving away of you,
emission of a photon toward you accelerates it
and the energy is subtracted from the photon energy.

In both cases, the extra energy increases with the source speed.

-- 
Poutnik ( the Czech word for a wanderer )

Knowledge makes a great man humble, but a small man arrogant.

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