The Naked Scientists

The Naked Scientists Forum

Author Topic: Does gravitational field increase energy of a photon?  (Read 15685 times)

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Hi naked scientists.
Gravitational field increases frequency of a photon. Does it increase energy of the photon?                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       


 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #1 on: 17/07/2011 08:18:43 »
Hi naked scientists.
Gravitational field increases frequency of a photon. Does it increase energy of the photon? 

Its all relative.
From the perspective of the photon its frequency remains unchanged therefore its energy is also unchanged. 
From a reference frame deeper within a gravitational field time is dilated therefore its frequency is increased giving the appearance of an increase in energy.  Dilated time also allows energy measurements on the photon to show an increase in energy but it's all relative.  The photon itself has not increased its energy, it just appears that it has.

This will probably not be viewed as a mainstream answer so is best not quoted.  But to the best of my knowledge there is nothing in it that is not correct.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #2 on: 17/07/2011 12:24:15 »
Thank you,Mike,for your opinion.Your opinion is logical. But we should think about length of a wave also. Gravitational meter is shorter,therefore photon should bypass longer objects.Then gravitational field should increase length of photon wave. :(
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #3 on: 17/07/2011 13:33:37 »
Thank you,Mike,for your opinion.Your opinion is logical. But we should think about length of a wave also. Gravitational meter is shorter,therefore photon should bypass longer objects.Then gravitational field should increase length of photon wave. :(

I don't understand what you are saying here?

An incoming light wave is more blue shifted the deeper it falls in the gravity well.
An outgoing light beam from within the gravity well will be red shifted at source relative to an observer outside the gravity well.  Is that what you meant?

An increased gravitational field dilates the meter or time.  Hence the longer wavelength.
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #4 on: 17/07/2011 16:38:04 »
You don't know.And you don't want to think. :D
If in far space from gravitational field photon can bypass object,length of which is one meter.But length of such object in gravitational field is shorter,therefore the photon bypasses such object with a stock in gravitational field.Length of wave of photon relative of object in gravitational field should be longer.If you don't understand this my logic,then I refuse to understand the your logic.Because the my logic is continuation of the your logic. :P
« Last Edit: 17/07/2011 16:43:11 by simplified »
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #5 on: 17/07/2011 17:17:21 »
Thank you,Mike,for your opinion.Your opinion is logical. But we should think about length of a wave also. Gravitational meter is shorter,therefore photon should bypass longer objects.Then gravitational field should increase length of photon wave. :(

Gravity dilates time or length.
A meter in a higher gravitational field is not shorter but longer.  The same applies to the length of a photon wave if originating within the higher gravitational field.
« Last Edit: 17/07/2011 17:21:23 by MikeS »
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #7 on: 17/07/2011 18:03:41 »
Yes, of course you are right.  I need to get back to you on this.

I wasn't thinking straight.  I got confused trying to understand what you are saying.

:D
If in far space from gravitational field photon can bypass object,length of which is one meter.But length of such object in gravitational field is shorter,therefore the photon bypasses such object with a stock in gravitational field.Length of wave of photon relative of object in gravitational field should be longer. :P

I still don't understand this.  Could you re-phrase it please.
« Last Edit: 17/07/2011 18:13:50 by MikeS »
 


Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #9 on: 17/07/2011 18:57:30 »
Thanks CPT
interesting article.

It looks like my original explanation was right and if not mainstream, should be.
 

Offline lightarrow

  • Neilep Level Member
  • ******
  • Posts: 4586
  • Thanked: 7 times
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #10 on: 17/07/2011 19:10:48 »
Hi naked scientists.
Gravitational field increases frequency of a photon. Does it increase energy of the photon?
It's quite straightforward, since photon's energy E is proportional to its frequency ν according to E = hν.      
 

Offline lightarrow

  • Neilep Level Member
  • ******
  • Posts: 4586
  • Thanked: 7 times
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #11 on: 17/07/2011 19:12:12 »
Its all relative.
From the perspective of the photon its frequency remains unchanged therefore its energy is also unchanged.
The perspective of the photon doesn't exist.
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #12 on: 18/07/2011 06:22:34 »
Hi naked scientists.
Gravitational field increases frequency of a photon. Does it increase energy of the photon?
It's quite straightforward, since photon's energy E is proportional to its frequency ν according to E = hν.      
I hope this formula faultlessly works in various heights of Earth. :)
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #13 on: 18/07/2011 07:07:31 »


I still don't understand this.  Could you re-phrase it please.
[/quote]"Frequency of wave is unchanging,length of wave is unchanging"
Then if you measure the unchanging length of wave by short meter,you receive the greater length of a wave than the measured length of wave by usual meter.You cannot imagine various length of meter. I live in Russia and I even have(on my work) meter which is longer  by 10 millimeters  :o
« Last Edit: 18/07/2011 07:11:17 by simplified »
 

Offline Soul Surfer

  • Neilep Level Member
  • ******
  • Posts: 3345
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
Does gravitational field increase energy of a photon?
« Reply #14 on: 18/07/2011 08:34:23 »
The simple answer to this question is yes!  in just the same way that a lump of matter would gain energy (and in effect mass) as it fell towards a gravitating body.
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #15 on: 18/07/2011 09:45:13 »


I still don't understand this.  Could you re-phrase it please.
"Frequency of wave is unchanging,length of wave is unchanging"
Then if you measure the unchanging length of wave by short meter,you receive the greater length of a wave than the measured length of wave by usual meter.You cannot imagine various length of meter. I live in Russia and I even have(on my work) meter which is longer  by 10 millimeters  :o
[/quote]


Gravity must be weaker in Russia then!  That would account for how good the Russians were at launching Rockets.  ;) ;) ;)

Will get back to you on above question.


« Last Edit: 18/07/2011 11:45:56 by MikeS »
 

Offline imatfaal

  • Neilep Level Member
  • ******
  • Posts: 2787
  • rouge moderator
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #16 on: 18/07/2011 11:09:19 »
Mod note

Guys - Can we keep speculations and off-the wall theories to the New Theories board - especially as there is already a virtually identical thread there.  LA and SS have given brief and accepted answers to this question - if you wish to ask more about those then please continue; however, if you wish to talk about less accepted ideas please do it on the New Theories thread.

Additionally, to allow others to follow threads please try to use the quote function. 
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #17 on: 18/07/2011 12:17:17 »
Mod note

Guys - Can we keep speculations and off-the wall theories to the New Theories board - especially as there is already a virtually identical thread there.  LA and SS have given brief and accepted answers to this question - if you wish to ask more about those then please continue; however, if you wish to talk about less accepted ideas please do it on the New Theories thread.

 


I agree they have given accepted answers but it is a mis-interpretation of general relativity.

"METHODOLOGICAL NOTES
This paper is concerned with the classical phenomenon of gravitational red shift, the decrease in the measured frequency of a photon moving away from a gravitating body (e.g., the Earth). Of the two current interpretations, one is that at higher altitudes the frequency-measuring clocks (atoms or atomic nuclei) run faster, i.e. their characteristic frequencies are higher, while the photon frequency in a static gravitational field is independent of the altitude and so the photon only reddens relative to the clocks. The other approach is that the photon reddens because it loses the energy when overcoming the attraction of the gravitational field. This view, which is especially widespread in popular science literature, ascribes such notions as a 'gravitational mass' and 'potential energy' to the photon. Unfortunately, also scientific papers and serious books on the general theory of relativity often employ the second interpretation as a 'graphic' illustration of mathematically immaculate results. We show here that this approach is misleading and only serves to create confusion in a simple subject."

http://iopscience.iop.org/1063-7869/42/10/A04

Full article here
http://www.itep.ru/theor/persons/lab180/okun/em_13.pdf
Thanks CPT ArkAngel for the links yesterday.

This was my answer to the question which the above paper shows to be correct.  I have not proposed anything new just trying to interpret general relativity in the correct manner.

"Its all relative.
From the perspective of the photon its frequency remains unchanged therefore its energy is also unchanged. 
From a reference frame deeper within a gravitational field time is dilated therefore its frequency is increased giving the appearance of an increase in energy.  Dilated time also allows energy measurements on the photon to show an increase in energy but it's all relative.  The photon itself has not increased its energy, it just appears that it has.

This will probably not be viewed as a mainstream answer so is best not quoted.  But to the best of my knowledge there is nothing in it that is not correct."     
 

Offline PhysBang

  • Hero Member
  • *****
  • Posts: 588
  • Thanked: 14 times
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #18 on: 18/07/2011 12:40:05 »
It does not show you to be correct. You need to learn a lot more about general relativity before you start correcting people.
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #19 on: 18/07/2011 13:03:46 »


I still don't understand this.  Could you re-phrase it please.
"Frequency of wave is unchanging,length of wave is unchanging"
"Then if you measure the unchanging length of wave by short meter,you receive the greater length of a wave than the measured length of wave by usual meter.You cannot imagine various length of meter. I live in Russia and I even have(on my work) meter which is longer  by 10 millimeters  ":o
[/quote]

Viewed from deeper within a gravitational field the frequency of the incoming photon increases as does its wavelength.  The wavelength increases because length contracts.  The frequency increases because time dilates.

The above sentence is wrong, it should read

Viewed from deeper within a gravitational field the frequency of the incoming photon increases as its wavelength shortens.  The wavelength decreases because length contracts.  The frequency increases because time dilates.
  Modified 19.07.11 1134
« Last Edit: 19/07/2011 11:40:08 by MikeS »
 

Post by MikeS click to view.

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #20 on: 18/07/2011 13:09:31 »
Shrunk
It does not show you to be correct. You need to learn a lot more about general relativity before you start correcting people.

Your entitled to your opinion.
 

Offline lightarrow

  • Neilep Level Member
  • ******
  • Posts: 4586
  • Thanked: 7 times
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #21 on: 18/07/2011 14:53:05 »
I agree they have given accepted answers but it is a mis-interpretation of general relativity.

"METHODOLOGICAL NOTES
This paper is concerned with the classical phenomenon of gravitational red shift, the decrease in the measured frequency of a photon moving away from a gravitating body (e.g., the Earth). Of the two current interpretations, one is that at higher altitudes the frequency-measuring clocks (atoms or atomic nuclei) run faster, i.e. their characteristic frequencies are higher, while the photon frequency in a static gravitational field is independent of the altitude and so the photon only reddens relative to the clocks. The other approach is that the photon reddens because it loses the energy when overcoming the attraction of the gravitational field. This view, which is especially widespread in popular science literature, ascribes such notions as a 'gravitational mass' and 'potential energy' to the photon. Unfortunately, also scientific papers and serious books on the general theory of relativity often employ the second interpretation as a 'graphic' illustration of mathematically immaculate results. We show here that this approach is misleading and only serves to create confusion in a simple subject."
And where did I have written about "gravitational potential energy of a photon"? The photon, going down to a less altitude, acquires more energy. Why it does it, it's another story. But since it has more energy, it authomatically has a greater frequency, that's all.

Quote
Full article here
http://www.itep.ru/theor/persons/lab180/okun/em_13.pdf
Thanks CPT ArkAngel for the links yesterday.

This was my answer to the question which the above paper shows to be correct.  I have not proposed anything new just trying to interpret general relativity in the correct manner.

"Its all relative.
From the perspective of the photon
...
I can't find that phrase (the one I have coloured in blue) in the document you linked, can you please show me at which line of text it is?
« Last Edit: 18/07/2011 14:57:46 by lightarrow »
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #22 on: 19/07/2011 06:11:56 »
I agree they have given accepted answers but it is a mis-interpretation of general relativity.

"METHODOLOGICAL NOTES
This paper is concerned with the classical phenomenon of gravitational red shift, the decrease in the measured frequency of a photon moving away from a gravitating body (e.g., the Earth). Of the two current interpretations, one is that at higher altitudes the frequency-measuring clocks (atoms or atomic nuclei) run faster, i.e. their characteristic frequencies are higher, while the photon frequency in a static gravitational field is independent of the altitude and so the photon only reddens relative to the clocks. The other approach is that the photon reddens because it loses the energy when overcoming the attraction of the gravitational field. This view, which is especially widespread in popular science literature, ascribes such notions as a 'gravitational mass' and 'potential energy' to the photon. Unfortunately, also scientific papers and serious books on the general theory of relativity often employ the second interpretation as a 'graphic' illustration of mathematically immaculate results. We show here that this approach is misleading and only serves to create confusion in a simple subject."
And where did I have written about "gravitational potential energy of a photon"? The photon, going down to a less altitude, acquires more energy. Why it does it, it's another story. But since it has more energy, it authomatically has a greater frequency, that's all.

Quote
Full article here
http://www.itep.ru/theor/persons/lab180/okun/em_13.pdf
Thanks CPT ArkAngel for the links yesterday.

This was my answer to the question which the above paper shows to be correct.  I have not proposed anything new just trying to interpret general relativity in the correct manner.

"Its all relative.
"From the perspective of the photon". I can't find that phrase (the one I have coloured in blue) in the document you linked, can you please show me at which line of text it is?

That's a quote from my first post in this thread, not from the document.  I tried to make this clear by saying "This was my answer to the question".  Sorry if that has caused any confusion.
 

Offline simplified

  • Sr. Member
  • ****
  • Posts: 428
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #23 on: 19/07/2011 06:49:50 »


I still don't understand this.  Could you re-phrase it please.
"Frequency of wave is unchanging,length of wave is unchanging"
"Then if you measure the unchanging length of wave by short meter,you receive the greater length of a wave than the measured length of wave by usual meter.You cannot imagine various length of meter. I live in Russia and I even have(on my work) meter which is longer  by 10 millimeters  ":o

Viewed from deeper within a gravitational field the frequency of the incoming photon increases as does its wavelength.  The wavelength increases because length contracts.  The frequency increases because time dilates.
[/quote]You have increased length of wave!You have increased frequency of wave!Then you should increase speed of light,becouse c=λν
You arrived in deadlock because your first step was wrong. ;)
 

Offline MikeS

  • Neilep Level Member
  • ******
  • Posts: 1044
  • The Devils Advocate
    • View Profile
Does gravitational field increase energy of a photon?
« Reply #24 on: 19/07/2011 11:31:41 »


I still don't understand this.  Could you re-phrase it please.
"Frequency of wave is unchanging,length of wave is unchanging"
"Then if you measure the unchanging length of wave by short meter,you receive the greater length of a wave than the measured length of wave by usual meter.You cannot imagine various length of meter. I live in Russia and I even have(on my work) meter which is longer  by 10 millimeters  ":o

Viewed from deeper within a gravitational field the frequency of the incoming photon increases as does its wavelength.  The wavelength increases because length contracts.  The frequency increases because time dilates.
"You have increased length of wave! You have increased frequency of wave!Then you should increase speed of light,becouse c=λν
You arrived in deadlock because your first step was wrong."


Yes you are quite right sorry for the confusion.  What happened was you didn't stipulate whether you were talking about incoming or outgoing photons.  In my last post for some reason I was thinking about incoming photons when considering frequency and outgoing when considering wavelength.  I went back and modified my post to add incoming but overlooked the mistake.

The sentence should read
Viewed from deeper within a gravitational field the frequency of the incoming photon increases as its wavelength shortens.  The wavelength decreases because length contracts.  The frequency increases because time dilates.

For anyone following this thread who would like clarification of time dilation.  An incoming photons has a certain frequency, x number of cycles per second.  Deeper within the gravity well time dilates.  A second becomes longer.  A greater number of cycles arrive in this longer second.
« Last Edit: 19/07/2011 11:54:55 by MikeS »
 

The Naked Scientists Forum

Does gravitational field increase energy of a photon?
« Reply #24 on: 19/07/2011 11:31:41 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums