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Re: 'Dark Matter'

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  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-10 21:18 +0200
    Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-10 13:51 -0700
      Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-10 15:58 -0500
        Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-11 01:04 +0200
          Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-11 07:49 -0500
            Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 06:26 -0700
              Re: 'Dark Matter' Sam Wormley <swormley1@gmail.com> - 2015-08-11 08:31 -0500
              Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-11 09:41 -0400
                Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 06:51 -0700
                  Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-11 13:44 -0400
                    Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 11:00 -0700
                      Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-11 18:44 +0000
                Re: 'Dark Matter' Sam Wormley <swormley1@gmail.com> - 2015-08-11 08:51 -0500
                  Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 07:17 -0700
                    Re: 'Dark Matter' Sam Wormley <swormley1@gmail.com> - 2015-08-11 10:45 -0500
                      Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 09:50 -0700
                        Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-11 10:01 -0700
                  Re: 'Dark Matter' Mahipal <mahipal7638@gmail.com> - 2015-08-11 08:10 -0700
            Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 13:44 +0200
              Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 07:51 -0500
    Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-10 21:28 +0000
      Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-10 14:35 -0700
        Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-10 23:31 +0000
          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 15:22 +0200
            Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 14:43 +0000
              Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 19:39 +0200
                Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 18:06 +0000
                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 20:23 +0200
                    Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 19:37 +0000
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 00:39 +0200
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 15:38 +0200
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:25 +0200
                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 17:15 +0200
                              Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 17:31 +0200
                                Re: 'Dark Matter' R Kym Horsell <kym@kymhorsell.com> - 2015-08-16 16:09 +0000
                                  Re: 'Dark Matter' [OT] Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 18:47 +0200
                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 10:38 +0200
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 11:09 +0200
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 12:40 +0200
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:17 +0200
                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:46 +0200
                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 10:42 +0200
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 11:21 +0200
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 12:58 +0200
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:19 +0200
                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:49 +0200
                  light is magneto-electrical noTthaTguY <abu.kuanysh05@gmail.com> - 2015-08-13 19:10 -0700
                Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 13:49 -0500
                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 20:50 +0200
                    Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 14:03 -0500
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 00:43 +0200
                        Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-15 17:53 -0700
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 09:34 +0200
                          Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-16 08:05 -0400
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 11:36 +0200
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:00 +0200
                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:22 +0200
                              Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:30 +0200
                                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:56 +0200
                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 11:17 +0200
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 11:26 +0200
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 13:01 +0200
            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 10:14 +0200
              Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 10:43 +0200
                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 13:07 +0200
                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:21 +0200
                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 17:07 +0200
      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-11 01:03 +0200
        Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-10 23:40 +0000
          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 13:41 +0200
            Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 14:54 +0000
              Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-13 08:13 -0700
                Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 10:46 -0500
                  Re: 'Dark Matter' noTthaTguY <abu.kuanysh05@gmail.com> - 2015-08-13 09:48 -0700
                  Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-13 10:00 -0700
                    Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 13:45 -0500
                Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 16:01 +0000
                Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-14 07:07 -0400
                  Re: 'Dark Matter' noTthaTguY <abu.kuanysh05@gmail.com> - 2015-08-14 10:39 -0700
              Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 20:29 +0200
                Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-08-13 19:14 +0000
                  Re: 'Dark Matter' Felipe Delgado <fd@spreadspectrum.org> - 2015-08-13 19:28 +0000
                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-15 15:38 +0200
                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 12:23 +0200
                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:04 +0200
                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:32 +0200
                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 16:33 +0200
                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 17:02 +0200
                              Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 19:24 +0200
                                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 20:31 +0200
                                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 22:16 +0200
                                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 22:38 +0200
                                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 20:45 +0200
                                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 22:32 +0200
                                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 22:57 +0200
                                      Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 23:22 +0200
                                        Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 23:34 +0200
                                          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 23:38 +0200
                                            Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-18 07:43 +0200
                                              Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-18 08:07 -0700
                                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 21:40 +0200
                                Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 22:35 +0200
                                  Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-16 23:36 +0200
                                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 23:50 +0200
                                    Re: 'Dark Matter' Poutnik <poutnik4nntp@gmail.com> - 2015-08-17 07:56 +0200
        Re: 'Dark Matter' Odd Bodkin <bodkinodd@gmail.com> - 2015-08-11 07:48 -0500
          Re: 'Dark Matter' Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-08-13 13:41 +0200

Page 4 of 6 — ← Prev page 1 2 3 [4] 5 6  Next page →

#514181

Poutnik wrote:

> Dne 13/08/2015 v 20:50 Thomas 'PointedEars' Lahn napsal(a):
>> Odd Bodkin wrote:
>>> Are you seriously claiming that the only situation where conservation of
    ^^^^^^^^^^^^^^^^^^^^^^^^^^
>>> momentum applies where a photon is radiated away (carrying momentum) is
>>> when the recoiling object is ALSO a photon?
>> No, that is just another straw man argument of yours.
> 
> No, it was a question, provoked by your statements.

Look up “straw man argument”.  It was _not_ only a question.  It was an 
insinuation.

> Insulting of others is low way of thinking
> and is common case
> among scientists of 3rd or 4th order.

This could be taken as an insult.

 
PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

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#514193

Dne 16/08/2015 v 11:26 Thomas 'PointedEars' Lahn napsal(a):
> Poutnik wrote:
> 
>> Dne 13/08/2015 v 20:50 Thomas 'PointedEars' Lahn napsal(a):
>>> Odd Bodkin wrote:
>>>> Are you seriously claiming that the only situation where conservation of
>     ^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>> momentum applies where a photon is radiated away (carrying momentum) is
>>>> when the recoiling object is ALSO a photon?
>>> No, that is just another straw man argument of yours.
>>
>> No, it was a question, provoked by your statements.
> 
> Look up “straw man argument”.  It was _not_ only a question.  It was an 
> insinuation.
> 
>> Insulting of others is low way of thinking
>> and is common case
>> among scientists of 3rd or 4th order.
> 
> This could be taken as an insult.

could it be taken as "Shot goose has the loudest shout" ?

You are hard on others,
while soft toward yourself.

-- 
Poutnik ( the Czech word for a wanderer )

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#514159

Dne 13/08/2015 v 15:22 Thomas 'PointedEars' Lahn napsal(a):

> 
> A “recoiling emitting plasma particle”, what crankish nonsense.  Read on the 
> plasma state of matter, and stellar nucleosynthesis, before further 
> comments, will you?
> 

When a ion in plasma emits a photon with momentum p,
ion recoils gains the opposite momentum difference -p.

Similarly for absorption.

Where is the nonsense ?


-- 
Poutnik ( the Czech word for a wanderer )

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#514173

Poutnik wrote:

> Dne 13/08/2015 v 15:22 Thomas 'PointedEars' Lahn napsal(a): 
>> A “recoiling emitting plasma particle”, what crankish nonsense.  Read on
>> the plasma state of matter, and stellar nucleosynthesis, before further
>> comments, will you?
> 
> When a ion in plasma emits a photon with momentum p,
> ion recoils gains the opposite momentum difference -p.
> 
> Similarly for absorption.
> 
> Where is the nonsense ?

You took my statement out of context.  To begin with, this is only true in 
the *individual ion’s* rest frame.

 
PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

[toc] | [prev] | [next] | [standalone]

#514194

Dne 16/08/2015 v 10:43 Thomas 'PointedEars' Lahn napsal(a):
> Poutnik wrote:
> 
>> Dne 13/08/2015 v 15:22 Thomas 'PointedEars' Lahn napsal(a): 
>>> A “recoiling emitting plasma particle”, what crankish nonsense.  Read on
>>> the plasma state of matter, and stellar nucleosynthesis, before further
>>> comments, will you?
>>
>> When a ion in plasma emits a photon with momentum p,
>> ion recoils gains the opposite momentum difference -p.
>>
>> Similarly for absorption.
>>
>> Where is the nonsense ?
> 
> You took my statement out of context. 

No, I did not. I was addressing
your objection against expression.
“recoiling emitting plasma particle”.

But if you did not object to that expression,
I was mistaken and withdraw my comment.

> To begin with, this is only true in 
> the *individual ion’s* rest frame.

No. This is true, if there is no other momentum exchange.

If there is, there is additional momentum change
due this exchange,
not cancelling the effect, if it was not there.
-- 
Poutnik ( the Czech word for a wanderer )

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#514288

Poutnik wrote:

> Dne 16/08/2015 v 10:43 Thomas 'PointedEars' Lahn napsal(a):
>> Poutnik wrote:
>>> Dne 13/08/2015 v 15:22 Thomas 'PointedEars' Lahn napsal(a):
>>>> A “recoiling emitting plasma particle”, what crankish nonsense.  Read
>>>> on the plasma state of matter, and stellar nucleosynthesis, before
>>>> further comments, will you?
>>> When a ion in plasma emits a photon with momentum p,
>>> ion recoils gains the opposite momentum difference -p.
>>>
>>> Similarly for absorption.
>>>
>>> Where is the nonsense ?
>> You took my statement out of context.
> 
> No, I did not. […]

Yes, you did.  The statement was made in the context of a specific claim of 
someone else.

> [tl;dr]

-- 
PointedEars

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#514305

Dne 16/08/2015 v 16:21 Thomas 'PointedEars' Lahn napsal(a):
> Poutnik wrote:
> 
>> Dne 16/08/2015 v 10:43 Thomas 'PointedEars' Lahn napsal(a):
>>> Poutnik wrote:
>>>> Dne 13/08/2015 v 15:22 Thomas 'PointedEars' Lahn napsal(a):
>>>>> A “recoiling emitting plasma particle”, what crankish nonsense.  Read
>>>>> on the plasma state of matter, and stellar nucleosynthesis, before
>>>>> further comments, will you?
>>>> When a ion in plasma emits a photon with momentum p,
>>>> ion recoils gains the opposite momentum difference -p.
>>>>
>>>> Similarly for absorption.
>>>>
>>>> Where is the nonsense ?
>>> You took my statement out of context.
>>
>> No, I did not. […]
> 
> Yes, you did.  The statement was made in the context of a specific claim of 
> someone else.

I can imagine it was in context of your overreacting.


-- 
Poutnik ( the Czech word for a wanderer )

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#512575

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Odd Bodkin wrote:
>>> When that photon left the sun, the sun also recoiled a little in the
>>> opposite direction.
>> Your other ideas aside: What about the other photons?
> 
> It recoils from them as well.
> 
> Since the sun is spherically symmetric with photons going in all
> direction, it all pretty much adds up to zero, and the sun doesn't move.

The Sun is not a solid body.  Since the two of you are arguing based on 
Newtonian mechanics (which is interesting to say the least, given the nature 
of the photon), if the Sun recoiled in all directions simultaneously, it 
would have to shrink.  However, no shrinking of the Sun due to recoiling 
from photon emissions has been reported to date.  (It does shrink as it 
loses mass–energy, ca. 4.289 × 10¹² g∕s, by emission of radiation.)

> (not that we could measure the recoil from a single photon of something as
> massive as the sun)

Or, because the Sun is basically *a ball of hot plasma*, it does not recoil 
at all, in any direction, but rotates slower and cools down instead as it 
loses momentum by emission of electromagnetic radiation.


PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

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#512589

Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:

>Michael Moroney wrote:

>> Since the sun is spherically symmetric with photons going in all
>> direction, it all pretty much adds up to zero, and the sun doesn't move.

>The Sun is not a solid body.  Since the two of you are arguing based on 
>Newtonian mechanics (which is interesting to say the least, given the nature 
>of the photon), if the Sun recoiled in all directions simultaneously, it 
>would have to shrink.  However, no shrinking of the Sun due to recoiling 
>from photon emissions has been reported to date.

Newtonian mechanics works well enough for the emitting plasma particle's
behavior, or the sun as a whole.  The (slight) force trying to shrink the
sun is counterbalanced by its heat trying to expand the plasma and it's in
steady state.

You are probably right that it's best to consider just the emitting plasma
particle rather than the sun as a whole since it's not solid, but it's 
still true that the net reaction of the whole sun recoiling is still
accurate (as Newtonian mechanics demands) even if the recoil of the sun
as a whole is just a very slight shift caused by the motion of one of its
components.

>Or, because the Sun is basically *a ball of hot plasma*, it does not recoil 
>at all, in any direction, but rotates slower and cools down instead as it 
>loses momentum by emission of electromagnetic radiation.

If you add the sum total of the motion of all the zillions of 
ions/electrons that compose the sun before and after there will be a
very slight net shift.  Momentum is conserved.

The energy of the photon, of course, does cool the sun slightly.

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#513222

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Michael Moroney wrote:
>>> Since the sun is spherically symmetric with photons going in all
>>> direction, it all pretty much adds up to zero, and the sun doesn't move.
>> The Sun is not a solid body.  Since the two of you are arguing based on
>> Newtonian mechanics (which is interesting to say the least, given the
>> nature of the photon), if the Sun recoiled in all directions
>> simultaneously, it
>> would have to shrink.  However, no shrinking of the Sun due to recoiling
>> from photon emissions has been reported to date.
> 
> Newtonian mechanics works well enough for the emitting plasma particle's
> behavior, or the sun as a whole.

Utter nonsense.  Stellar dynamics is the quintessential evidence that both 
special and general relativity are correct, and that classical mechanics 
suffices as an approximation only for *low* speeds, *low* energies and so 
on.  In particular, E_kin = mv²∕2 and p = mv from classical mechanics *do 
not hold* for massless photons: their kinetic energy is _not_ zero, and 
their momentum is not zero; they are moving at *the speed of light* instead.

> The (slight) force trying to shrink the sun is counterbalanced by its heat
> trying to expand the plasma and it's in steady state.

You wish.

> You are probably right that it's best to consider just the emitting plasma
> particle

There you go again: “the emitting plasma particle”?  Do you even know what a 
plasma is?

>> Or, because the Sun is basically *a ball of hot plasma*, it does not
>> recoil at all, in any direction, but rotates slower and cools down 
>> instead as it loses momentum by emission of electromagnetic radiation.
> 
> If you add the sum total of the motion of all the zillions of
> ions/electrons that compose the sun before and after there will be a
> very slight net shift.

Cite evidence.

> Momentum is conserved.

Of that there is no doubt.  However, I debate that any momentum is 
transported by any recoiling of stellar matter.  Photons are _not_ like 
little energetic cannonballs as (the two of) you like to believe.
 
> The energy of the photon, of course, does cool the sun slightly.

Nonsense.  If you knew what a plasma is in the first place, you would know 
that its temperature is more or less equivalent to the velocity of its 
constituents, and that

  E² = (pc)² + (mc²)²    (1)

whereas E is energy, p is momentum, c is the speed of light in vacuum, and m 
is mass.  As for the photon (which, I should add, is not a “plasma 
particle”, as you apparently believe), m = 0, and so

   E = pc           (2)
     = ℎc∕λ = ℎf.   (3)

IOW, the “relativistic mass”, which is equal to its energy, and the 
momentum, of a photon all depend only on the wavelength/frequency of the 
electromagnetic radiation it emerges as a constituent of under collision 
conditions [Einstein confirmed this in 1905 in his work on the photoelectric 
effect, and later showed the relation between Planck’s equation (3) and 
mass–energy equivalence (1)(2)].  And it is the momentum that a photon (or 
rather, zillions of photons per second) carries away from the Sun that 
causes the Sun either to cool down or its rotation to become slower.  It is 
the energy that it carries away that causes the Sun to shrink; _not_ because 
of any recoiling, but because of the mass–energy equivalence it thereby 
loses mass as well (fear not: calculations show that the mass of the Sun is 
so large, it will not shrink considerably during its lifetime merely due to 
emission of radiation or other particles).


PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

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#513273

Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:

>Michael Moroney wrote:

>> Newtonian mechanics works well enough for the emitting plasma particle's
>> behavior, or the sun as a whole.

>Utter nonsense.  Stellar dynamics is the quintessential evidence that both 
>special and general relativity are correct, and that classical mechanics 
>suffices as an approximation only for *low* speeds, *low* energies and so 
>on.

That's why I wrote that Newtonian mechanics works for the plasma
particles and the sun as a whole, not the photon.

>> The (slight) force trying to shrink the sun is counterbalanced by its heat
>> trying to expand the plasma and it's in steady state.

>You wish.

The sun is hot and is trying to expand.  Gravity and the recoil from 
photons emitted outward counter this.  The sun has been around for 
billions of years, it's in steady state.  Of course the shrinkage from the
photons is trivial, but is nonzero.


>> If you add the sum total of the motion of all the zillions of
>> ions/electrons that compose the sun before and after there will be a
>> very slight net shift.

>Cite evidence.

>> Momentum is conserved.

That's your evidence.

>> The energy of the photon, of course, does cool the sun slightly.

>Nonsense.  If you knew what a plasma is in the first place, you would know 
>that its temperature is more or less equivalent to the velocity of its 
>constituents, and that

Energy is conserved as well.  As hot things radiate photons, they cool
off, as conservation of energy requires.  Of course the sun is constantly
fusing hydrogen which replaces this energy, so it won't actually drop in
temperature for billions of years.

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#513275

Explain wave trains.
Because single photons don't come
from the Sun- wave trains do.
How does your Hydrogen atom
emit "a" photon, and then that photon
gets into lockstep with thousands of
others?????
?????
Which "sun" are you talking about?
Couldn't be ours.
Which "reality" are you talking about?
Couldn't be ours.

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#513280

On 8/13/2015 10:13 AM, john wrote:
> Explain wave trains.
> Because single photons don't come
> from the Sun- wave trains do.
> How does your Hydrogen atom
> emit "a" photon, and then that photon
> gets into lockstep with thousands of
> others?????

What makes you think that photons get into lockstep?

You have this image that if light exhibits a wavelength oscillation, 
then this means you've got a whole slew of photons all wiggling in 
lockstep with each other?

No. Photons that are all in phase with each other -- lockstep as you 
call it -- come from a laser. It's called coherent light.

Sunlight is not coherent. The sun is not a laser.

I think you just have some goofy idea about what a wavetrain means for 
the photons in it.

> ?????
> Which "sun" are you talking about?
> Couldn't be ours.
> Which "reality" are you talking about?
> Couldn't be ours.
>


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

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#513288

yes, but Young's two-pikhole experiment used sunlight
(from another pinhole in hte wall of the barn

> Sunlight is not coherent. The sun is not a laser.
> 
> I think you just have some goofy idea about what a wavetrain means for 
> the photons in it.
> 
> > ?????
> > Which "sun" are you talking about?
> > Couldn't be ours.
> > Which "reality" are you talking about?
> > Couldn't be ours.
> >
> 
> 
> -- 
> Odd Bodkin --- maker of fine toys, tools, tables

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#513293

Books I read on the sun says photons
do not arrive individually,
but in wave trains up to several
hundred photons long.
I guess the books are wrong, hey, Odd?

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#513318

On 8/13/2015 12:00 PM, john wrote:
> Books I read on the sun says photons
> do not arrive individually,
> but in wave trains up to several
> hundred photons long.

Maybe you could cite the books. Title, author, page.

> I guess the books are wrong, hey, Odd?

Maybe. Let's look at the books you've read that say that.
If you can't remember what books you've read, maybe you don't remember 
accurately what the book said, either.


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

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#513284

john <johnsefton288@gmail.com> writes:

>Explain wave trains.
>Because single photons don't come
>from the Sun- wave trains do.
>How does your Hydrogen atom
>emit "a" photon, and then that photon
>gets into lockstep with thousands of
>others?????
>?????

Lockstep?  WTF are you talking about? The sun is not a laser.

Read up on black body radiation for more details on sunlight.

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#513490

On 8/13/2015 11:13 AM, john wrote:
> Explain wave trains.
> Because single photons don't come
> from the Sun- wave trains do.

Kooks of the world. Join hands. Get on the wave train. Wave train.



-- 
Cut off one head, two more shall take its place.
HAIL HYDRA!
https://www.youtube.com/watch?v=FZcG5UOY224

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#513619

til; you have a nice definition of "photon,
that does not rely on the nonparticle nature of waves,
forged aboud id

> > Explain wave trains.
> > Because single photons don't come
> > from the Sun- wave trains do.

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#513317

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Michael Moroney wrote:
>>> Newtonian mechanics works well enough for the emitting plasma particle's
>>> behavior, or the sun as a whole.
>> Utter nonsense.  Stellar dynamics is the quintessential evidence that 
>> both special and general relativity are correct, and that classical 
>> mechanics suffices as an approximation only for *low* speeds, *low*
>> energies and so on.
> 
> That's why I wrote that Newtonian mechanics works for the plasma
> particles and the sun as a whole, not the photon.

How did you get the idea that the constituents of the Sun, which as I said 
is basically a hot plasma, would move at low speeds, and there would be low 
energies involved?

> [nonsense]
 

PointedEars
-- 
“Science is empirical: knowing the answer means nothing;
 testing your knowledge means everything.”
   —Dr. Lawrence M. Krauss, theoretical physicist,
    in “A Universe from Nothing” (2009)

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