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'Dark Matter'

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  'Dark Matter' john <johnsefton288@gmail.com> - 2015-07-27 07:28 -0700
    'Dark Matter' john <johnsefton288@gmail.com> - 2015-07-27 18:16 -0700
      Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-07-28 07:17 -0400
      Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-07-28 15:18 -0700
        Re: 'Dark Matter' moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-07-29 02:22 +0000
      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
    Re: 'Dark Matter' "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-07-29 13:27 -0700
    Re: 'Dark Matter' "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-08-16 14:42 -0700
    Re: 'Dark Matter' "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-08-18 14:01 -0700
      Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-18 20:21 -0700
      Re: 'Dark Matter' benj <nobody@gmail.com> - 2015-08-19 01:26 -0400
        Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-19 06:07 -0400
          Re: 'Dark Matter' Sam Wormley <swormley1@gmail.com> - 2015-08-19 08:05 -0500
          Re: 'Dark Matter' john <johnsefton288@gmail.com> - 2015-08-19 07:04 -0700
            Re: 'Dark Matter' HVAC <Mr.HVAC@gmail.com> - 2015-08-19 19:14 -0400
    Re: 'Dark Matter' "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-08-19 09:12 -0700

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#512730

Keep looking.
I might glance back- it wasn't posted
long ago

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#512734

Here you go Sam.
You posted it yourself.
Didn't you read it?

"Hubble finds evidence of galaxy star birth regulated by black-hole fountain 
> http://phys.org/news/2015-08-thickets-stars-elliptical-galaxies.html 


> Astronomers have uncovered a unique process for how the universe's 
> largest elliptical galaxies continue making stars long after their 
> peak years of star birth. NASA's Hubble Space Telescope's exquisite 
> high resolution and ultraviolet-light sensitivity allowed the 
> astronomers to see brilliant knots of hot, blue stars forming along 
> the jets of active black holes found in the centers of giant 
> elliptical galaxies. 

> Combining Hubble data with observations from a suite of ground-based 
> and space telescopes, two independent teams found that that the black 
> hole, jets, and newborn stars are all parts of a self-regulating 
> cycle. High-energy jets shooting from the black hole heat a halo of 
> surrounding gas, controlling the rate at which the gas cools and 
> falls into the galaxy. 

> "Think of the gas surrounding a galaxy as an atmosphere," explained 
> the lead of the first study, Megan Donahue of Michigan State 
> University. "That atmosphere can contain material in different 
> states, just like our own atmosphere has gas, clouds, and rain. What 
> we are seeing is a process like a thunderstorm. As the jets propel 
> gas outward from the center of the galaxy, some of that gas cools and 
> precipitates into cold clumps that fall back toward the galaxy's 
> center like raindrops." 

> "The 'raindrops' eventually cool enough to become star-forming clouds 
> of cold molecular gas, and the unique far ultraviolet capabilities of 
> Hubble allowed us to directly observe these 'showers' of star 
> formation," explained the lead of the second study, Grant Tremblay of 
> Yale University. "We know that these showers are linked to the jets 
> because they're found in filaments and tendrils that wrap around the 
> jets or hug the edges of giant bubbles that the jets have inflated," 
> said Tremblay, "And they end up making a swirling 'puddle' of 
> star-forming gas around the central black
hole"

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#512705

On Tuesday, August 11, 2015 at 9:52:01 AM UTC-4, Sam Wormley wrote:
> On 8/11/15 8:41 AM, HVAC wrote:
> > On 8/11/2015 9:26 AM, john wrote:
> >> Yes, Odd.
> >> It IS my sub-photon idea.
> >>
> >> The next fractal layer- the sub-atoms
> >> making up electrons- is 10^31 times
> >> smaller in diameter. Therefore each
> >> volume is the square of that. Sub-photons
> >> will each carry 1/10^62 as much energy
> >> as regular ones. But there will be
> >> 10^62 times more of them, so they
> >> carry just as much energy in total.
> >>
> > This is John's 'Sub-Photon Theory'.
> >
> > To anyone who is worried that when Bert dies we will have no more crazy
> > shit to laugh at, I submit that John is waiting in the wings and will
> > carry on once Bert has gone up to heaven.

This is HVAC's physics contribution. See how insightful, see The Show!

>    John is a generation younger than Herbert Glazier. John is registered
>    at crank dot net. He doesn't even try to sort life. He just pokes fun
>    at physics because he doesn't understand any of it.

While you Sam can't even poke at physics due to your own shortcomings.

>    It's a pity that sci.physics is infested with crackpots and trolls. No
>    wonder it's hard for the likes of John to make any progress.

A certain Stephen Hawking is also, as you say, 'registered' on
crank.net, you chicken shit Sam Wormley. More pity.

Sam sam SAM... read today's headlines:
EPA CAUSES COLORADO TOXIC HEAVY METAL SPILL!

EPA, those would be your peeps. Sam, I'm disappointed, aren't you
supposed to cut and paste climate changing environmental news?

Isn't it ironic, now they'll want more money to clean up the mess that
resources consuming humans are making on their==the(y)TheThem's
precious little Earth. Raise taxes now!  Fine, EPA will admit, there
wasn't an environmental problem before, there is NOW! Look at those
rivers!! Calm down peeps, no time for pointing fingers. Especially
those middle ones. Unite! The Doom is finally here, forget that we had
to diabolically bring it upon ourselves. Picky picky PICKY...

> -- 
> 
> sci.physics is an unmoderated newsgroup dedicated
> to the discussion of physics, news from the physics
> community, and physics-related social issues.

-- Mahipal 'Jon Stewart sure picked a bad time to quit!'

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#513225

Odd Bodkin wrote:

> On 8/10/2015 6:04 PM, Thomas 'PointedEars' Lahn wrote:
>> Odd Bodkin wrote:
>>> On 8/10/2015 3:51 PM, john wrote:
>>>> Yes, Odd.
>>>> Perhaps there ARE other photons!!
>>> And so calculate the measurable implications of that.
>> Which would be?
> 
> It's his sub-photon idea. Let him calculate it.

It is your absurd “photon emission causes the Sun to recoil” idea.  I let 
you do the math of that, if you can, so that you can prove that you are 
capable of more than the mentioned regurgitating.


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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#513232

On 8/13/2015 6:44 AM, Thomas 'PointedEars' Lahn wrote:
> Odd Bodkin wrote:
>
>> On 8/10/2015 6:04 PM, Thomas 'PointedEars' Lahn wrote:
>>> Odd Bodkin wrote:
>>>> On 8/10/2015 3:51 PM, john wrote:
>>>>> Yes, Odd.
>>>>> Perhaps there ARE other photons!!
>>>> And so calculate the measurable implications of that.
>>> Which would be?
>>
>> It's his sub-photon idea. Let him calculate it.
>
> It is your absurd “photon emission causes the Sun to recoil” idea.  I let
> you do the math of that, if you can, so that you can prove that you are
> capable of more than the mentioned regurgitating.

Sure. So let's take a photon of wavelength 450 nm. The momentum of the 
emitted photon is hc/lambda, which you can calculate to be 2.76 eV/c.

The recoil will likely be suffered by the sole atom that radiated it, 
and for hydrogen, for example, it's rather easy to calculate the speed 
of the recoiling atom:
beta*c = p/(gamma*m) = (2.76 eV/c)(938E6 eV/c^2), where gamma ~ 1.
Thus we know beta ~ 3E-9 for the recoiling atom.

If this recoil were conveyed via interactions to the remainder of the 
sun (as it will be, eventually), then we can use the figure of merit 
that there 8E56 atoms in the sun, and so the recoil speed of the sun is 
beta = 0.4E-65.

But it is still true, ye olde web designer and Star Trek fanboy, that 
momentum is conserved.

>
>
> PointedEars
>


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

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#512527

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

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#512533

And, Michael, once those photons
leave the sun, does it make any
difference to that sun what they do or do not
encounter? Momentum-wise or anything
else-wise?

No.

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#512588

john <johnsefton288@gmail.com> writes:

>And, Michael, once those photons
>leave the sun, does it make any
>difference to that sun what they do or do not
>encounter? Momentum-wise or anything
>else-wise?

>No.

You finally got something right.

There are two events.  The sun emits a photon and recoils (actually the
emitting plasma particle recoils as the sun is not solid, as was pointed
out)  The photon later hits your eye (or a tree) and transmits its
momentum and energy to you (or the tree).

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#513247

Michael Moroney wrote:

> john <johnsefton288@gmail.com> writes:
>> And, Michael, once those photons
>> leave the sun, does it make any
>> difference to that sun what they do or do not
>> encounter? Momentum-wise or anything
>> else-wise?
>> 
>> No.
> 
> You finally got something right.
> 
> There are two events.  The sun emits a photon and recoils (actually the
> emitting plasma particle recoils as the sun is not solid, as was pointed
> out) 

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

> The photon later hits your eye (or a tree) and transmits its
> momentum and energy to you (or the tree).

Nonsense.  One photon, which emerges as such when it hits the observer’s 
retina, carries energy E = pc = ℎc∕λ = ℎf (IOW: p = ℎ∕λ) which is used to 
activate the proteins in the photoreceptor cells in the retina.  (It has 
been shown [I can cite papers] that one photon suffices for that, but 
naturally there are considerably more photons involved in visual 
perception.)  Only in *that* sense momentum p of the photon is involved at 
the observer’s side of the process.


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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#513268

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

>Michael Moroney wrote:

>> There are two events.  The sun emits a photon and recoils (actually the
>> emitting plasma particle recoils as the sun is not solid, as was pointed
>> out) 

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

Pointed Ears, the momentum of a photon is p = hf/c.  Momentum is always
conserved.  Therefore, *something* *must* recoil with momentum p = -hf/c.
That something would be, initially, the plasma particle(s) that were 
involved with emitting the photon.  As these transfer their momentum to
the sun as a whole through collisions or other interactions, the sun as a
whole would have to acquire a momentum of -hf/c.  Simple physics.
As Odd pointed out, that amount of momentum applied to something as 
massive as the sun results in a ridiculously small velocity, but it is 
(must be) nonzero.

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#513302

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Michael Moroney wrote:
>>> There are two events.  The sun emits a photon and recoils (actually the
>>> emitting plasma particle recoils as the sun is not solid, as was pointed
>>> out)
>> A "recoiling emitting plasma particle", what crankish nonsense.  Read on
>> the plasma state of matter, and stellar nucleosynthesis, before further
>> comments, will you?
> 
> Pointed Ears, the momentum of a photon is p = hf/c.
         ^
Without the space.  Yes, it is.

> Momentum is always conserved.

Yes.  AISB.

> Therefore, *something* *must* recoil with momentum p = -hf/c.

No.  I think we have finally determined the underlying, oversimplying 
fallacy of (the two of) you.  Your disregard of the *direction* of momentum 
(it is a *vector* quantity) aside:

  E = E_kin = p c

and

  p = ℎ f∕c

are *only* true for particles with mass m = 0, as assumed for photons, 
because of

  E_kin = √((m c²)² + (p c)²) − m c²

(the kinetic energy gained by a body is the difference between the energy it 
has in relative motion and the energy it has at relative rest), and

  E² = p² c² + m² c⁴

which *only for m = 0* leads to

   p = E∕c

and for photons with

   E = ℎ f

to

   p = ℎ f∕c.

But the Sun does not consist only of photons.  In fact, it consists of more 
stuff that does not manifest itself as a photon than vice-versa.  Stuff 
whose mass is not zero.  Stuff that does not emit those photons in the first 
place.


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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#513312

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

>Michael Moroney wrote:

>> Momentum is always conserved.

>Yes.  AISB.

>> Therefore, *something* *must* recoil with momentum p = -hf/c.

>No.  I think we have finally determined the underlying, oversimplying 
>fallacy of (the two of) you.  Your disregard of the *direction* of momentum 
>(it is a *vector* quantity) aside:

Yes it is a vector, but with the simplification of the photon moving
in the x direction, the y and z components are both zero.  Therefore,
photon's momentum is p = hf/c in the x direction, and the recoil must be
-hf/c (that is, in the -x direction) to keep the sum zero (and conserve 
momentum).

Are you thinking that in the recoil "f" is somehow the frequency of the
recoiling particle?  It's not; it's the frequency of the departing photon.
It has to be mentioned here to balance momentum.  The recoiling particle(s)
electrons and/or nuclei, obviously have mass and p=hf/c doesn't apply
to them directly, it's just that they have momentum equal to and opposite
of that of the photon's.

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#513315

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>>Michael Moroney wrote:
>>> Momentum is always conserved.
>> Yes.  AISB.
>>> Therefore, *something* *must* recoil with momentum p = -hf/c.
>> No.  I think we have finally determined the underlying, oversimplying
>> fallacy of (the two of) you.  Your disregard of the *direction* of
>> momentum (it is a *vector* quantity) aside:
> 
> Yes it is a vector, but with the simplification of the photon moving
> in the x direction, the y and z components are both zero.

That is the *other* *oversimplification* you are doing.

> Therefore, photon's momentum is p = hf/c in the x direction, and the
> recoil must be -hf/c (that is, in the -x direction) to keep the sum zero
> (and conserve momentum).

Again, no.  Whatever could recoil is _not_ a photon; it has a mass not equal 
to zero.  Its momentum is calculated *differently* than that of a photon.
 
> Are you thinking that in the recoil "f" is somehow the frequency of the
> recoiling particle? 

No, I think you have no idea what you are talking about to begin with.

> It's not; it's the frequency of the departing photon.

I know.

> [snip nonsense]

You have a misconception as to what “conservation of momentum” means.  The 
whole thing goes: “In an *isolated* system, total momentum is conserved.”
An isolated system is one where there are no interactions with its 
surroundings at all.

Even if one views the Sun as a isolated system, which it is not, the total 
momentum of all of its particles is conserved; not only that of two of them 
participating in the interaction that you are wishing for, and which does 
not happen in the first place.

More could be said about this, but I let you chew on this first.


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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#513334

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

>Michael Moroney wrote:

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

>>>> Therefore, *something* *must* recoil with momentum p = -hf/c.
>>> No.  I think we have finally determined the underlying, oversimplying
>>> fallacy of (the two of) you.  Your disregard of the *direction* of
>>> momentum (it is a *vector* quantity) aside:
>> 
>> Yes it is a vector, but with the simplification of the photon moving
>> in the x direction, the y and z components are both zero.

>That is the *other* *oversimplification* you are doing.

OK.  Give me a vector example of a particle emitting a photon and
recoiling, which can *not* be simplified from a 3 vector to a case of
momentums of p and -p in the x direction, with y & z components zero, 
simply by aligning the x axis with the direction of the photon.

>> Therefore, photon's momentum is p = hf/c in the x direction, and the
>> recoil must be -hf/c (that is, in the -x direction) to keep the sum zero
>> (and conserve momentum).

>Again, no.  Whatever could recoil is _not_ a photon; it has a mass not equal 
>to zero.  Its momentum is calculated *differently* than that of a photon.
> 
>> Are you thinking that in the recoil "f" is somehow the frequency of the
>> recoiling particle? 

>No,

Yes you do, by your answer above stating what's recoiling is not a photon.
It's not, of course, but its momentum is still -hf/c, where f is the
frequency of the photon emitted, *NOT* some frequency of the recoiling
particle.

Its momentum is mv; and for momentum to be conserved, mv = -hf/c,
which is why I wrote its momentum is -hf/c.

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#513997

Michael Moroney wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Michael Moroney wrote:
>>> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>>>>> Therefore, *something* *must* recoil with momentum p = -hf/c.
>>>> No.  I think we have finally determined the underlying, oversimplying
>>>> fallacy of (the two of) you.  Your disregard of the *direction* of
>>>> momentum (it is a *vector* quantity) aside:
>>> Yes it is a vector, but with the simplification of the photon moving
>>> in the x direction, the y and z components are both zero.
>> That is the *other* *oversimplification* you are doing.
> 
> OK.  Give me a vector example of a particle emitting a photon and
> recoiling, which can *not* be simplified from a 3 vector to a case of
> momentums of p and -p in the x direction, with y & z components zero,
> simply by aligning the x axis with the direction of the photon.

Well, where photons are first produced in the Sun, in proton–proton 
collisions in the core, at about 1.57 × 10⁷ K, there is no linear recoiling 
to begin with.  Whether there is any recoiling at all is very questionable.  
And there is actually no thing that emits them: they are simply a product of 
the fusion, and because momentum is preserved, the photon and the resulting 
helium-2 nucleus go off in different directions that cannot be traced to a 
single originating entity.

Likewise later, when photons are produced in electron–positron annihilation 
and deuterium–hydrogen fusion at 7 × 10⁶ to 2 × 10⁶ K.

And those photos are absorbed by the solar plasma after having traveled only 
short distances.  When they are re-emitted, that happens “in a random 
direction and usually at a slightly lower energy”.  So you can see that a 
recoiling in a particular direction cannot take place.  As that is not the 
case, statistically any individual recoiling or group of recoilings – which 
cannot be computed as simply as you claim – is neutralized by those in the 
respective opposite directions.  *Total* momentum is conserved.

<https://en.wikipedia.org/wiki/Sun#Photosphere>
<https://en.wikipedia.org/wiki/Sun#Photons_and_neutrinos>

AISB, the Sun does _not_ recoil from photon emission (and it does not shrink 
because of transfer of momentum).  Nor does the observer when a photon hits 
their retina (they would if the energy E = p c the photon carries was not 
fully converted in activating the photoreceptor cell; light pressure is an 
actual phenomenon).

Did I not recommend to you that you get yourself informed about stellar 
nuclear fusion, among other things?

>> […]  Whatever could recoil is _not_ a photon; it has a mass not
>> equal to zero.  Its momentum is calculated *differently* than that of a 
>> photon.
>>> Are you thinking that in the recoil "f" is somehow the frequency of the
>>> recoiling particle?
>> No,
> 
> Yes you do,

I think I know better what I am thinking than you, thank you very much.

> by your answer above stating what's recoiling is not a photon.

Non sequitur.

> It's not, of course, but its momentum is still -hf/c,

It is not, because the momentum of the origin of the emission, if it can be 
traced, is calculated differently – it cannot be defined by a frequency at 
all; because it does not need to be a full transfer of momentum (and in fact 
it is not: put simply, the Sun still exists although it is shining): and 
because it involves a direction that you are simply ignoring.


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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#514249

Dne 16/08/2015 v 00:39 Thomas 'PointedEars' Lahn napsal(a):

> AISB, the Sun does _not_ recoil from photon emission ...

It does, but it is cancelled by spherical symmetry.

"light pressure is an actual phenomenon".

It is light pressure seen from the other side, at the source.
As both operations, emission and absorption, are symmetrical.

Like 2 boys on 2 boats, mutually throwing the ball,
effectively repulsing themselves by "ball pressure"
at both sides, throwing and catching.

> ............... (and it does not shrink
> because of transfer of momentum).

It does, by departing light pressure, but it can be neglected,
and is supported by dynamic equilibrium.

> Nor does the observer when a photon hits 
> their retina (they would if the energy E = p c the photon carries was not 
> fully converted in activating the photoreceptor cell; light pressure is an 
> actual phenomenon).

Linear nor angular momentum transfer
from the photon to atoms / molecules
is given by law.

It is not detemined
by way how the absorbed energy is transformed.
It only detemines, how they are redistributed.


-- 
Poutnik ( the Czech word for a wanderer )

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#514289

Poutnik wrote:

> Dne 16/08/2015 v 00:39 Thomas 'PointedEars' Lahn napsal(a):
>> AISB, the Sun does _not_ recoil from photon emission ...
> 
> It does,

The Sun *itself* does _not_ recoil.  Period.

> but it is cancelled by spherical symmetry.

Nonsense.

> "light pressure is an actual phenomenon".
> 
> It is light pressure seen from the other side, at the source.
> As both operations, emission and absorption, are symmetrical.

Light pressure in the Sun – the proper term there is radiation pressure – is 
directed *outward* from the center.  It was claimed that it would be 
directed *inward* in some way, which is nonsense.

Learn to read before I decide to killfile you.

Did I already say that I detest people who do not even extend others the 
simple courtesy of introducing themselves, and stand by their statements, 
with their real name?

-- 
PointedEars

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#514307

Dne 16/08/2015 v 16:25 Thomas 'PointedEars' Lahn napsal(a):
> Poutnik wrote:
> 
>> Dne 16/08/2015 v 00:39 Thomas 'PointedEars' Lahn napsal(a):
>>> AISB, the Sun does _not_ recoil from photon emission ...
>>
>> It does,
> 
> The Sun *itself* does _not_ recoil.  Period.


> 
>> but it is cancelled by spherical symmetry.
> 
> Nonsense.

So you agree with the first line.
> 
>> "light pressure is an actual phenomenon".
>>
>> It is light pressure seen from the other side, at the source.
>> As both operations, emission and absorption, are symmetrical.
> 
> Light pressure in the Sun – the proper term there is radiation pressure – is 
> directed *outward* from the center.  It was claimed that it would be 
> directed *inward* in some way, which is nonsense.

Light pressure IN the Sun aka radiation pressure
is different phenomena.

I have spoken about radiation to space.

> 
> Learn to read before I decide to killfile you.

Learn to read and behave or I will killfile you again.
> 
> Did I already say that I detest people who do not even extend others the 
> simple courtesy of introducing themselves, and stand by their statements, 
> with their real name?
> 
Did you say Usenet never expose the use adresses
in spite of I have seen them exposed many times ?

Was it mistake or lie ?

BTW, my name is Libor Striz,
but as internet is so anonymous, it does not matter much.

You say I am a liar, so I must have invented it.

-- 
Poutnik ( the Czech word for a wanderer )

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#514309

Dne 16/08/2015 v 17:15 Poutnik napsal(a):
> Dne 16/08/2015 v 16:25 Thomas 'PointedEars' Lahn napsal(a):
>> Poutnik wrote:
>>

>>
>> Did I already say that I detest people who do not even extend others the 
>> simple courtesy of introducing themselves, and stand by their statements, 
>> with their real name?
>>
> Did you say Usenet never expose the use adresses
> in spite of I have seen them exposed many times ?
> 
> Was it mistake or lie ?
> 
> BTW, my name is Libor Striz,, more exactly Stříž
> but as internet is so anonymous, it does not matter much.
> 
> You say I am a liar, so I must have invented it.
> 
OTOH, You claim to be Thomas Lahn,
but it may or may not be true.

Some people come with fake real name,( I do not mean you )
while others come with nickname they honour.

I use my nick Poutnik  or Poutnikl ( l as Libor, as it is common among
Czechs ), as I honour it, being my real nickname and penname as well.


-- 
Poutnik ( the Czech word for a wanderer )

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#514318

Poutnik <poutnik4nntp@gmail.com> wrote:
> Dne 16/08/2015 v 17:15 Poutnik napsal(a):
>> Dne 16/08/2015 v 16:25 Thomas 'PointedEars' Lahn napsal(a):
>>> Poutnik wrote:
>>> Did I already say that I detest people who do not even extend others the 
>>> simple courtesy of introducing themselves, and stand by their statements, 
>>> with their real name?
>> Did you say Usenet never expose the use adresses
>> in spite of I have seen them exposed many times ?
>> Was it mistake or lie ?
>> BTW, my name is Libor Striz,, more exactly St???
>> but as internet is so anonymous, it does not matter much.
>> You say I am a liar, so I must have invented it.
> OTOH, You claim to be Thomas Lahn,


Unfortunately for his parents, it's true.

> but it may or may not be true.
> Some people come with fake real name,( I do not mean you )
> while others come with nickname they honour.
> I use my nick Poutnik  or Poutnikl ( l as Libor, as it is common among
> Czechs ), as I honour it, being my real nickname and penname as well.

-- 
> What's causing Global Warming, Will?
Why do you care, Sam?
Myself, I do not know and that is fine with me.
There many more important things that I do not know! 
-- Will Janoschkadiction, 21 Apr 2012

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