Photons and conservation momentum (split from Pioneer anomaly)

[Strange]

How can radiation from the space probe towards empty space possible have a decelerating impact on the pioneer space probes..

 

Can you please explain why you emphasize "towards empty space"; why do you think that is relevant? Do you think that rockets don't work in space because they need something to push against?

[swansont]

On the one hand, yes I know that words (or mathematic) is not enough.

The scientific method must be passed, before something can be said to be “certain knowledge”

 

On the other hand, much of what we today call science, has never passed any scientific method, but anyway presented like, - certain knowledge.

Also the discussion we have here, is hard for me to see really have passed the any scientific method.

As I so fare see it, - it is only a mathematically based speculation (?)

Unless hard evidence really can be presented (which unfortunately, doesn’t seems to be the case) - I (at least) will remain sceptic until then. ..

Still I am asking for hard evidence.

Imagine we will shot a flashlight out in space, with the lights on.

Do someone really believe that the flashlight would start accelerating opposite the light cone, as a small fantasy spacecraft in star wars ?

It simple exceeds my imagination - until hard evidence shows such thesis is correct.

 

Lots of evidence in here:

http://en.wikipedia.org/wiki/Radiation_pressure

 

As an aside, it's hard to take a critique seriously when it is based upon argument from ignorance

[Strange]

If the conservation of momentum were violated as you suggest then this would be equivalent to a violation of Lorentz invariance (thanks to Noether's Theorem). This has been (and still is being) tested to extraordinarily high levels of accuracy (about10^-43 for some experiments).

[Bjarne]

 

Radiation pressure is well-accepted (and well-documented) physics. People, including myself, have been using lasers to manipulate atoms via conservation of momentum for decades. If you want to discuss details of it, start a new thread.

 

 

I wish you would have moved this post as well, because as you can see in my first post in this new thread I wrote (se below)...

 

 

It sounds acceptable that the opposite, - which mean photon bombarding / hidding the space probe - could have an effect, and either accelerate of decelerate the space probe.

But photons leaving the space probe? - no, - unless there are hard evidence, - such is really difficult to believe.

 

Yes laser can manipulate atoms, and even created magnetic fields.

But I think Niels Bohr would have said, - this is a completely different experiment.

 

Anyway, - as I wrote above, - (in the first post of this (new) thread) - I could accept that radiation bombardment can convert to kinetic energy. '

But I am (especially) not convinced that radiation emitted from a source really can convert to kinetic energy (motion of an object).

 

I don’t believe that a flashlight would begin to move in space.

You could then say that if I would accept that radiation impact can convert to kinetic energy - I also have to accept the opposite (recoil effect).

In the same way, - that if it will not be recoil from a gun the bullet wouldn’t move.

 

But why is it necessary to keep both these radiation phenomena’s at classical mechanical understanding level?

 

Radiation absorption / impact could have a classic mechanic energy converting effect (radiation to kenetic energy), yes, - but why should that necessarily also apply for emitting radiation.

 

In a quantum mechanics universe not must make logical sense.

Think about decay, is it not stupid to claim that due to decay radiation some of the energy go back to the Uran where the emission started. ?

What would that energy do there if the radiation is isotropic ? – More hokus pokus seems to be necessary.

 

If this all was true we can build a spacecraft that can travel the next million years, (and who knows maybe reach almost c) just by controlling the reflecting radiation direction form plutonium waste opposite the direction we want to move.

I think if NASA would build such s spacecraft they would be dissapointed.

Sorry until we have hard evidence this sound to me as science fiction star war hokus pokus science.

Edited December 2, 2014 by Bjarne

[Sensei]

Think about decay, is it not stupid to claim that due to decay radiation some of the energy go back to the Uran where the emission started. ?

What would that energy do there if the radiation is isotropic ? – More hokus pokus seems to be necessary.

 

What?!

If you have no idea about radioactivity, here is thread to read by you...

http://www.scienceforums.net/topic/86454-half-life-and-radioactivity-need-an-explanation/

 

Radioactivity we can see on our own eyes, see

http://www.scienceforums.net/topic/86284-particle-detectors/

Edited December 2, 2014 by Sensei

[swansont]

Yes laser can manipulate atoms, and even created magnetic fields.

But I think Niels Bohr would have said, - this is a completely different experiment.

No, not really.

 

Anyway, - as I wrote above, - (in the first post of this (new) thread) - I could accept that radiation bombardment can convert to kinetic energy. '

But I am (especially) not convinced that radiation emitted from a source really can convert to kinetic energy (motion of an object).

 

I don’t believe that a flashlight would begin to move in space.

You could then say that if I would accept that radiation impact can convert to kinetic energy - I also have to accept the opposite (recoil effect).

In the same way, - that if it will not be recoil from a gun the bullet wouldn’t move.

Why wouldn't momentum and energy be conserved? Do you have something besides personal incredulity to cite?

 

 

But why is it necessary to keep both these radiation phenomena’s at classical mechanical understanding level?

You're denying classical mechanics is correct, so isn't this the level to discuss it? There's not a whole lot of physics in play beyond the classical level anyway. Only the quantization of photon energies, and that's irrelevant.

 

Radiation absorption / impact could have a classic mechanic energy converting effect (radiation to kenetic energy), yes, - but why should that necessarily also apply for emitting radiation.

Because the law of conservation of momentum works even when you reverse the direction of time.

 

In a quantum mechanics universe not must make logical sense.

Think about decay, is it not stupid to claim that due to decay radiation some of the energy go back to the Uran where the emission started. ?

What would that energy do there if the radiation is isotropic ? – More hokus pokus seems to be necessary.

 

If this all was true we can build a spacecraft that can travel the next million years, (and who knows maybe reach almost c) just by controlling the reflecting radiation direction form plutonium waste opposite the direction we want to move.

Sorry until we have hard evidence this sound to me as science fiction star war hokus pokus science.

Again, your ability to understand something has no actual effect on it being true.

 

The problem with using EMR as propulsion is not the physics being incorrect, but the size of the effect. p = E/c, so F = P/c (p is momentum, P is power), so a 1 watt laser, or flashlight, will produce 3.33 nanonewtons of thrust. It's impractical, but it's not wrong.

[Strange]

In a quantum mechanics universe not must make logical sense.

 

That isn't true. And it doesn't mean you can make up any old nonsense.

 

If this all was true we can build a spacecraft that can travel the next million years, (and who knows maybe reach almost c) just by controlling the reflecting radiation direction form plutonium waste opposite the direction we want to move.

 

 

It is called an ion drive. http://www.extremetech.com/extreme/144296-nasas-next-ion-drive-breaks-world-record-will-eventually-power-interplanetary-missions

 

Also, as noted for both solar sails and the Nichols radiometer, the effect is DOUBLED when the surface is reflected. This is because the emitted photons impart the same momentum and the received ones.

Edited December 2, 2014 by Strange

[Bjarne]

Why wouldn't momentum and energy be conserved?

This is not what I am saying.

Let me answer your questions with questions

Where does the energy from an electron goes when it disappears and where does it come from when it later pop up a new place ?

How does that happen and why ?

 

You're denying classical mechanics is correct, so isn't this the level to discuss it?

No, but I am not sure that a photon can be compared to a bullet..

 

There's not a whole lot of physics in play beyond the classical level anyway. Only the quantization of photon energies, and that's irrelevant.

Well a photon pops up (is emitted)

How can you know whether the principle for this to happen is exactly so "dramatically (recoil effect) as when firing a classic bullet from a Gun ?

How can you know that the all circumstances for comparing these 2 very different phenomena’s are exactly - classical - identical / comparable?

Sorry, - Firing a photon is in my universe is a quantum physic phenomena, - firing a bullet something very different, - until someone prove it to be wrong.

But this doesn’t necessarily mean that the photon not have momentum, but only the process how it get it could be different from classic phenomena’s.

In short, - a photon is really a strange cousin, no doubt about it.

 

Again, your ability to understand something has no actual effect on it being true.

I was only asking for hard evidence, - experiments able to convince a person difficult to convince.

Anyway - If I get what I am asking for , I can still not believe the Pioneer anomaly is solved

There are several reason for this, - as already mention some due the outstanding not solved issues,

 

Also, as noted for both solar sails and the Nichols radiometer, the effect is DOUBLED when the surface is reflected. This is because the emitted photons impart the same momentum and the received ones.

 

I never got an answer to the question whether this statement is tested elsewise as inside a calculator?

[Strange]

This is not what I am saying.

 

Yes it is. (The fact you don't realise that is what you are saying is part of the problem.)

 

Where does the energy from an electron goes when it disappears

 

When does an electron "disappear"?

 

How does that happen and why ?

 

You tell me. It sounds like something else you have made up.

 

No, but I am not sure that a photon can be compared to a bullet..

 

In some ways it can; e.g. it has momentum (which is conserved).

 

I was only asking for hard evidence, - experiments able to convince a person difficult to convince.

 

http://arxiv.org/abs/1304.5795

 

I never got an answer to the question whether this statement is tested elsewise as inside a calculator?

 

You did. You ignored it.

 

The actual, real, measured, observed, factual, hard, physical, existing, substantial, concrete, palpable, indubitable, authentic, perceptible, sensible, tangible, valid force for both solar sails and the Nichols radiometer is DOUBLED when the surface is reflected.

 

Did you get it that time? (You have been given several references where you can check the details.)

[swansont]

This is not what I am saying.

It's a direct implication.

 

Let me answer your questions with questions

Where does the energy from an electron goes when it disappears and where does it come from when it later pop up a new place ?

How does that happen and why ?

 

What does that have to do with photons?

 

 

No, but I am not sure that a photon can be compared to a bullet..

I am.

 

Well a photon pops up (is emitted)

How can you know whether the principle for this to happen is exactly so "dramatically (recoil effect) as when firing a classic bullet from a Gun ?

How can you know that the all circumstances for comparing these 2 very different phenomena’s are exactly - classical - identical / comparable?

Sorry, - Firing a photon is in my universe is a quantum physic phenomena, - firing a bullet something very different, - until someone prove it to be wrong.

But this doesn’t necessarily mean that the photon not have momentum, but only the process how it get it could be different from classic phenomena’s.

In short, - a photon is really a strange cousin, no doubt about it.

 

I was only asking for hard evidence, - experiments able to convince a person difficult to convince.

Anyway - If I get what I am asking for , I can still not believe the Pioneer anomaly is solved

There are several reason for this, - as already mention some due the outstanding not solved issues,

I have used lasers to slow atoms down from thermal velocities down to velocities equivalent to a few microKelvin — around 1 cm/s. Photons are absorbed and re-emitted, conserving momentum at both steps. The systems behave just as physics predicts. It's not magic. If "difficult to convince" means "you can't prove it's not invisible unicorns" then this is moot. But for someone who isn't denying basic physics, that's a solid as it gets.

 

Firing a photon may be QM, but that about the process, not about whether photons have momentum, and whether absorption/emission can exert a force, which is what's in question here.

 

 

 

I never got an answer to the question whether this statement is tested elsewise as inside a calculator?

 

Yes. I take it you didn't bother to check out the link Strange posted, because doing so would have trivially answered your question.

[Bjarne]

You did. You ignored it.

 

The actual, real, measured, observed, factual, hard, physical, existing, substantial, concrete, palpable, indubitable, authentic, perceptible, sensible, tangible, valid force for both solar sails and the Nichols radiometer is DOUBLED when the surface is reflected.

 

Did you get it that time? (You have been given several references where you can check the details.)

Still I have only your words, not any source / links to detailed described test, - done at real solar sails.

And regarding the Nichols radiometer, it rotate due rotation of warm air, so fare I have understood, not du to (only) reflected radiation.

I have mention this before, but did not got a reply to it.

 

When does an electron "disappear"?

An electron can absorb energy in very small amounts (called quanta), disappear and instantly reappear at higher energy state as if it was teleported.

It's called a quantum leap and occurs through the wave–particle duality principle.

The electron kind of turns from a particle into a wave and back into a particle again in a different location.

This has led to the idea that the electron vanish an reappear in and out of existence.

 

 

http://arxiv.org/abs/1304.5795

 

There are no describtion here that shows evidence for what I was asking for .

It seems you did't got my point.

[swansont]

 

And regarding the Nichols radiometer, it rotate due rotation of warm air, so fare I have understood, not du to (only) reflected radiation.

 

 

That would be quite a trick, considering that it's been done under vacuum (see the Bell and Green link on the wikipedia page)

"The range of air pressure used extended down to about 10^-6 mm. of mercury."

[Bjarne]

 

What does that have to do with photons?

Seen from a photons own perspective no time and space exist, therefore also no motion.

Hence it must be everywhere at the same time.

It seems to be at least so strange as a electron.

 

How can you know whether it is our point of view or the photons point of view (the quantum reality) that really matter ? (in some cases)..

 

I am not saying this or that is correct or wrong, but only that I am not convienced all the time when I hear we know this and that.

 

For exsample, yesterday I read this http://physicsworld.com/cws/article/news/2008/oct/02/the-mystery-of-the-varying-nuclear-decay

If someone would have suggested this before the discovery was done he would be considered as a complete idiot, not able to understand anything.

Because the day before this was a absolute immovable fact.

 

All the time we are forces to change our understanding.

 

Let me ask a last question.

What if we one day is forced to understand that the pioneer anomaly not was solved.

What then about all the radiation "knowledge"?

Which parts of science must then be thrown over board ?

Edited December 2, 2014 by Bjarne

[Strange]

Still I have only your words, not any source / links to detailed described test, - done at real solar sails.

 

Hey, you know what: when the text is bright blue and underlines it is what we call a "hyperlink". It means you can "click" on the links and they take you to another "page" on the "web" where you can find more information. That "page" might have more "hyperlinks" to further "pages" which have yet more information. This amazing "web" of information is enabled by the success of science and technology (which you think is implausible).

 

For example, this is the Wikipedia page about solar sails: http://en.wikipedia.org/wiki/Solar_sail

 

It inlcudes information about real, practical, functioning solar sails and (wow!) links so you can find even more details about them. I suggest you read some of them instead of just repeatedly typing "I don't believe in science because it is too amazing... I don't believe in science because it is too amazing..."

 

And regarding the Nichols radiometer, it rotate due rotation of warm air, so fare I have understood, not du to (only) reflected radiation.

I have mention this before, but did not got a reply to it.

 

You did mention it before. And I did reply. My reply was that you are mistaken. It is the CROOKE'S radiometer where the movement is due to thermal effects.

 

The NICHOL'S radiometer moves due to radiation pressure. Here is an overview, again from Wikipedia (so there are more references to read up): http://en.wikipedia.org/wiki/Nichols_radiomete

 

There was also the original paper that imatfaal provided a link to. You should read it because they explain the reasons for using mirrored surfaces.

http://mesoscopic.mines.edu/mediawiki/images/3/39/Radiationpressure.pdf

 

There was also information on the effect on spectra caused by atoms recoiling when a photon is emitted.

http://quantummechanics.ucsd.edu/ph130a/130_notes/node429.html

 

And finally, the Yarkovsky effect:

 

a force acting on a rotating body in space caused by the anisotropic emission of thermal photons, which carry momentum.

http://en.wikipedia.org/wiki/Yarkovsky_effect

 

I don't know how much more direct evidence you need. Momentum IS conserved.

 

If you are still going to deny this then you will more evidence than "I don't believe it".

 

<garbage deleted>

This has led to the idea that the electron vanish an reappear in and out of existence.

 

Only in your head.

 

There are no describtion here that shows evidence for what I was asking for .

 

Presumably because you don't understand what you are saying.

Edited December 2, 2014 by Strange

[Bjarne]

 

That would be quite a trick, considering that it's been done under vacuum (see the Bell and Green link on the wikipedia page)

"The range of air pressure used extended down to about 10^-6 mm. of mercury."

Ahh I did first a google image search on Nichols radiometer and saw mostly Crookes' Radiometer

[Sensei]

For exsample, yesterday I read this http://physicsworld.com/cws/article/news/2008/oct/02/the-mystery-of-the-varying-nuclear-decay

If someone would have suggested this before the discovery was done he would be considered as a complete idiot, not able to understand anything.

Because the day before this was a absolute immovable fact.

 

That article is not correct.

The first paragraph

"It is well-known that a radioactive substance follows a fixed exponential decay, no matter what you do to it."

Is not entirely true.

For instance, if we have unstable isotope that is decaying through electron capture (or double electron capture), when we will ionize atom, stripping off all electrons from it, it won't be able to decay anymore..

When Beryllium-7 (that's decaying through electron capture exclusively) is part of larger chemical compound, decay rate also changes slightly.

[Bjarne]

 

 

For example, this is the Wikipedia page about solar sails: http://en.wikipedia.org/wiki/Solar_sail

 

The NICHOL'S radiometer moves due to radiation pressure. Here is an overview, again from Wikipedia (so there are more references to read up): http://en.wikipedia.org/wiki/Nichols_radiomete

 

There was also the original paper that imatfaal provided a link to. You should read it because they explain the reasons for using mirrored surfaces.

http://mesoscopic.mines.edu/mediawiki/images/3/39/Radiationpressure.pdf

 

There was also information on the effect on spectra caused by atoms recoiling when a photon is emitted.

http://quantummechanics.ucsd.edu/ph130a/130_notes/node429.html

 

And finally, the Yarkovsky effect:

http://en.wikipedia.org/wiki/Yarkovsky_effect

Yes i was googling images of NICHOL'S radiometer and saw must at all images of radiometer (as i allready know about)

Thank you this is what I was asking for.

Now I will read all this.

 

I don't know how much more direct evidence you need. Momentum IS conserved.

I must say I have never read about it before.

Allready I read a little about solar sails, yes it sounds convincing

But still the recoil part- hmmm how strong is that evidence ?

[Strange]

Seen from a photons own perspective no time and space exist, therefore also no motion.

 

Nonsense.

 

I am not saying this or that is correct or wrong

 

Yes you are.

 

but only that I am not convienced all the time when I hear we know this and that.

 

But we don't "know" (with that sort of certainty) anything. I can only assume you have been reading poor quality journalism.

 

Even conservation of momentum is not sacrosanct if you can provide evidence. That is why people keep coming up with more and more accurate tests.

 

If someone would have suggested this before the discovery was done he would be considered as a complete idiot, not able to understand anything.

Because the day before this was a absolute immovable fact.

 

Nonsense. This is contradicted by the article itself: "their measurements matched the 'magnetic seeds' predicted by theoretical studies"

 

All the time we are forces to change our understanding.

 

Of course. That is what science does. (Despite your ludicrous claims about "immovable facts".)

 

Let me ask a last question.

What if we one day is forced to understand that the pioneer anomaly not was solved.

What then about all the radiation "knowledge"?

Which parts of science must then be thrown over board ?

 

I don't understand your problem. On the one hand you complain about "immovable facts" (which don't exist) and then you worry that we might discover something new.

 

If more evidence or a better analysis or some new physics is found that results in a better answer, then that will be good news. It is not a religion. No one is worshiping Pioneer. The Anderson/Turyshev work is just a good detailed analysis that fits the facts pretty well. Maybe someone will come up with something better. There is nothing to stop you or anyone else trying to do that. It would be great. You could get a paper published.

 

But sitting there saying "I find physics implausible so I propose ... magic" is not going to impress anybody.

[swansont]

Seen from a photons own perspective no time and space exist, therefore also no motion.

Hence it must be everywhere at the same time.

It seems to be at least so strange as a electron.

 

How can you know whether it is our point of view or the photons point of view (the quantum reality) that really matter ? (in some cases)..

 

 

 

We don't have physics to explain what happens from the photon's point of view; the photon is not in a reference frame we can describe. All of our physics that applies here is in inertial reference frames.

 

Let me ask a last question.

What if we one day is forced to understand that the pioneer anomaly not was solved.

What then about all the radiation "knowledge"?

Which parts of science must then be thrown over board ?

 

Someone discovering that there was some other effect going on would not change the fact that photons carry momentum.

[Bjarne]

 

Nonsense.

Try to google l "time distance doesn't exist photons"

 

 

Yes you are.

 

No I am not

I ask for hard evidence to understand why the "Pioneer cass closed" seems to be based on such ugly science.

I have far from made my final conclusion that matter, but only begun to ask skeptical questions.

 

 

Even conservation of momentum is not sacrosanct if you can provide evidence. That is why people keep coming up with more and more accurate tests.

 

If my conclusion one day should be that here is a camel buried I promise you I will try to prove it (if I can)

And don't worry before I die I will prove that the Pioneer anomaly is not solved.

 

Nonsense. This is contradicted by the article itself: "their measurements matched the 'magnetic seeds' predicted by theoretical studies"

 

Sorry it was the wrong link, and I corrected it before you replied

http://physicsworld.com/cws/article/news/2008/oct/02/the-mystery-of-the-varying-nuclear-decay

 

Of course. That is what science does. (Despite your ludicrous claims about "immovable facts".)

 

I think that even if you would use the rest of your lifetime you would not be able to count how many times the internet is full claims, as for exsample we know the universe expands, we know there must be dark matter etc. etc and we know this and that.

 

 

I don't understand your problem. On the one hand you complain about "immovable facts" (which don't exist) and then you worry that we might discover something new.

 

I have no problems

But I think many will agree,that the radiation recoil speculation is a "immovable facts".

And well maybe it is, - all I did was only to ask for hard evidence, and not the same kind of "evidence" we so often hear.

 

If more evidence or a better analysis or some new physics is found that results in a better answer, then that will be good news.

It is not a religion. No one is worshiping Pioneer. The Anderson/Turyshev work is just a good detailed analysis that fits the facts pretty well. Maybe someone will come up with something better.

There is nothing to stop you or anyone else trying to do that. It would be great. You could get a paper published.

This is not the impression I got here at the forum the last 2 days.

Rather is seems that is evenh not very popular to be sceptical and ask critical questions, - and this is all I did.

 

If the cause of the pioneer anomaly should be proven different, - what then about the radiation theory ?

Are you saying you could be force to give up the Nasa explantion ?

 

Could you accept that this could be a wrong conclusion?

Or where would you then set in the artillery?

I mean where do you think the possible weakest point in NASA's explanation could be?

Dont ask me, I am as I said first beginning to analyse a possible weakness.

 

But sitting there saying "I find physics implausible so I propose ... magic" is not going to impress anybody.

Don't put words in my month I never wrote.

 

 

We don't have physics to explain what happens from the photon's point of view; the photon is not in a reference frame we can describe. All of our physics that applies here is in inertial reference frames.

Agree, this is normally our experience

But never say never.

Nasa's explanation is not nice, - furthermore I am convinced the last word in this case is not said.

 

Someone discovering that there was some other effect going on would not change the fact that photons carry momentum.

 

You are most likely right, but my point is only how did the photons get the momentum ?

Do we know everything about this process ?

Edited December 2, 2014 by Bjarne

[elfmotat]

Try to google l "time distance doesn't exist photons"

 

A lot of us know relativity quite well, and we know when you're making bogus claims. Photons do not "experience" anything, because talking about what a photon would experience from its perspective is a nonsensical question. There is no physical meaning behind those words. Photons do not have a perspective. We can't use physics to describe scenarios that violate the laws of physics.

 

This entire thread seems like a textbook example of an argument from personal incredulity. "I don't understand/believe it, so it can't be true!" With the exception of creationists and climate change deniers, rarely do I see people work so hard to deny evidence.

[Strange]

Try to google l "time distance doesn't exist photons"

 

Just because lots of other people repeat the same nonsense, doesn't mean it isn't nonsense.

 

I ask for hard evidence to understand why the "Pioneer close" case seems to be based on such ugly science

 

It isn't ugly; it is based on fundamental symmetries of the universe. And you have now been given "hard evidence" and theoretical justification.

 

I think that even if you would use the rest of your lifetime you would not be able to count how many times the internet is full claims, as for exsample we know the universe expands, we know there must be dark matter etc. etc and we know this and that.

 

That might be your problem: the Internet ≠ Science.

 

If the cause of the pioneer anomaly should be proven different, - what then about the radiation theory ?

 

If you (or someone) comes up with an alternative explanation then that will have to include an explanation of where the Anderson/Turyshev analysis is wrong. That won't be related to the momentum of electromagnetic radiation. But it could be because they have wrongly estimated temperatures, surface characteristics, or incorrectly calculated the effect on the velocity, etc. (I think one of the regular posters here is convinced there are such errors.)

 

Are you saying you could be force to give up the Nasa explantion?

Could you accept that this could be a wrong conclusion?

 

Of course. Why would I care? If that analysis is shown to be wrong, then that is how science makes progress.

 

 

Dont ask me, I am as I said first beginning to analyse a possible weakness.

 

Well, good luck. But you should start with the possible, then try the impossible before resorting to magic.

Sorry it was the wrong link, and I corrected it before you replied

http://physicsworld.com/cws/article/news/2008/oct/02/the-mystery-of-the-varying-nuclear-decay

 

So you dismiss fundamental aspects of physics as "speculation" but latch on to some unconfirmed (*) results as overthrowing "immovable facts". This is pretty irrational.

 

For example: http://arxiv.org/abs/0810.3265

Edited December 2, 2014 by Strange

[swansont]

 

You are most likely right, but my point is only how did the photons get the momentum ?

Do we know everything about this process ?

 

That hasn't been your point before. You have previously insisted that photons being emitted don't cause a recoil, and that's the subject of the discussion. Photons have a momentum of E/c. The process doesn't matter — that's just moving the goalposts.

[Mordred]

As others have mentioned photons exert a force as photons have momentum. There is a couple other areas where this is considered and applied.

http://en.m.wikipedia.org/wiki/Radiation_pressure

 

when we launch probes and satellites at different planets they calculate the radiation pressure due to the sun emitting various spectrums of light.

 

See link above.

 

In cosmology radiation including photons has an equation of state that correlates its energy density to its pressure influence. Google equations of state (cosmology)

http://en.m.wikipedia.org/wiki/Equation_of_state_(cosmology)

 

Photons can and do exert a force. Just as the others have been telling you.

See the equations on that page under ultra relativistic matter note it includes radiation.

Edited December 3, 2014 by Mordred

[Bjarne]

 

A lot of us know relativity quite well, and we know when you're making bogus claims. Photons do not "experience" anything, because talking about what a photon would experience from its perspective is a nonsensical question. There is no physical meaning behind those words. Photons do not have a perspective. We can't use physics to describe scenarios that violate the laws of physics.

 

This entire thread seems like a textbook example of an argument from personal incredulity. "I don't understand/believe it, so it can't be true!" With the exception of creationists and climate change deniers, rarely do I see people work so hard to deny evidence.

It is not my invention, but just a well known fact , - for a photon (perspetive or not) no time, distant can exsist.

If you (or someone) comes up with an alternative explanation then that will have to include an explanation of where the Anderson/Turyshev analysis is wrong.

I don't agree that a new theory must explain why Anderson/Turyshev is wrong,

New physics could for example be based on new space probes experiments, which then show "something" is wrong.

Let's say you will get the exact same magnitude anomaly, and no longer have the radiation explanation to blame

What then ?

 

 

So you dismiss fundamental aspects of physics as "speculation" but latch on to some unconfirmed (*) results as overthrowing "immovable facts". This is pretty irrational.

I only show a link, which is one of many example showing that sometime we are forced to rethink what everybody thought was certain knowledge.

Science is full of histories showing that "idiots" was right.

Another example is the WMAP data now confirm that there are gigantic holes in the BB theory.

Few years ago it was unthinkable that something could be wrong. Maybe the BB theory is wrong. Maybe there was something before the BB

These are words that comes from Europa’s fines University

The point is, that I think not many really are prepared for “certain knowledge” to be totally wrong.

Another point is, that we should not be so irritated (an punish) if someone ask idiotic and skeptical questions

The garbage can be buried where you least expect it.

 

That hasn't been your point before. You have previously insisted that photons being emitted don't cause a recoil, and that's the subject of the discussion. Photons have a momentum of E/c. The process doesn't matter — that's just moving the goalposts.

In my mind it was always the point, but yes I didn’t write it. It is really difficult to suggest or imagine what a photon maybe does and not does. It will only be speculation.

But I am asking whether a recoil effect really is a property of emission, or rather whether it is possible that the photon get its momentum in a way we simply cannot imagine, and that have nothing with classic mechanism to do.

The only way answering this is to experientially test. Maybe this is already done, maybe not (I haven’t so far had time to read through the links I got yesterday, to be convinced that such (classic) recoil effect really exist.

Edited December 3, 2014 by Bjarne