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ArcticMyst Security by Avery

can photons lose energy to anything?

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I wont go into the math and the jargon, but I have a wondering if light though any method, would lose energy during extreme distance of say 100 light years, if so the implications would be huge, light could be dark energy, it could also be that we are not in an expanding universe but the red shift is from photons loosing energy. discuss. its not a theory for fun.
 
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joeyss

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Re: can photons lose energy to quantum vortex

Wouldn't make sense since we'd still see the light with the decetors we have today.
 
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Re: can photons lose energy to quantum vortex

^^What?

A photon's energy is discreet. Very discreet.

But is the energy it carries the same things as what allows it to propagate ~c in the vacuum of space?

Nope.

It the momentum you are perhaps most interested in instead. Wave theory says a photons momentum decreases as it enters a more dense medium.

But the problem with photons is, quantum theory tells us the opposite - that momentum should increase as the photon enters a more dense medium.

The BIG problem is, that snell's law tell us

p = mv

but a quantum application says

p=h(bar)k where

k = nf/c

I'm tired of typing tonight.

Just read this:

http://arxiv.org/ftp/physics/papers/0607/0607094.pdf
 
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Re: can photons lose energy to quantum vortex

Thanks meatball, that was a good read, had to print it as my screen was killing my eyes after 2 minuets, I still don't fully understand why an EM wave could not be shifted into a longer wavelength by things like gravity or matter. 1.24 x 10-6 eV-m /.455 hell I don't even know how do do math symbols on a keyboard so we must just use real values so that's gives us 2.787 ev, nothing can take some energy from this equation once it is created?why. Thats my issue I don't see any law that prevents interaction with matter that would change the E of a photon, since I can't change the speed of light, and well plank's constant is a constant, I would have to take energy in the equation from, wavelength. I also might add why do we use C as a constant, what vacuum, have you ever seen a vacuum, I don't even think a true vacuum or absolute vacuum is possible. One last thing, how the hell do you make lambda with a keyboard is it like alt something?
 
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Well, photon energy is proportional to wavelength, and wavelength decreases if viewed from one object traveling away from the emitting object. It's called red shift. It doesn't apply to light in our galaxy, but the light from most other galaxies has lost energy (in a way) when it reaches us.
 

Benm

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I think the latter is rather confusing: If a photon is emitted in a distant galaxy, it will have exactly the same amount of energy when it arrives here. Surely not all of the photons make it here, making the light source dimmer, but this doesnt change the color of the light.

The red shift is 'caused' by the emitting source moving away at great speed, but this has nothing to do with energy loss in transit. The only factor that determines the red shift is the relative speed of the emitting and observing parties.

The distance between them doesnt have any influence on the amount of red shift, but the practical reality is that all objects that are very far away from us also move away from us at high speed.
 
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I think the latter is rather confusing: If a photon is emitted in a distant galaxy, it will have exactly the same amount of energy when it arrives here. Surely not all of the photons make it here, making the light source dimmer, but this doesnt change the color of the light.

The red shift is 'caused' by the emitting source moving away at great speed, but this has nothing to do with energy loss in transit. The only factor that determines the red shift is the relative speed of the emitting and observing parties.

The distance between them doesnt have any influence on the amount of red shift, but the practical reality is that all objects that are very far away from us also move away from us at high speed.

I understand doppler effect, I know about Hubble and his work, the issue I am having is, is this a case where the photon is indeed a single quanta of energy, and it cannot give off energy because it would be absorbed? What going on with the waveform of a single photon then, if the energy is the combined wavelength, freq, and momentum, then I see that as components of the photon so it don't feel like a quanta of energy, I see it as a particle made of energy that describes a waveform, its only a particle because of the combined factors of its energy, but then so are we. It should be able to lose energy by means of its waveform if it travels though distortion in time-space, such as well idk think of the crazy energies and masers that are going off at the far reaches of our light sphere, massive black holes, stuff we can't even see yet. Also what about our cooling background radiation, cooling EM would be the same as removing energy from it. Also if a photon is created with a huge amount of energy cannot it become 2 photons of lesser energy. I am not saying that Hubble was wrong I am just exploring possible other reasons for a photon to lose energy. Got to love free time, I can't have chats like this in my area. :p
 
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Wouldn't the cooling EM background just be from it slowly getting absorbed by all the mass in the universe?

As far as a photon losing energy but not being fully absorbed... it is called compton scattering.
 
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yes I know a black hole can reverse scatter creating x-ray photons, and the are other forces that can have effects on photons, I am at a limit though the understanding of time-space at a quantum scale limits any further delving, I need to read up some lol. But I remember some odd things about super-fluids that make me think a photon could lose energy by a tiny tiny fraction do to interaction by forces that exist even in a vacuum that are not well understood by me yet like QVD I think the whole of the background of time space is a super-fluid. or some form of Bose–Einstein condensate.


well I don't know if forces they exist in a pure vacuum, I still think a pure vacuum only obtainable at absolute 0 or no energy in it at all, so if a photons enters a vacuum, is it still a vacuum? or have we been out of vacuum since the big bang?
 
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Benm

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Also if a photon is created with a huge amount of energy cannot it become 2 photons of lesser energy.

It can under some circumstances. Even in free space it could create a particle/antipracticle pair, those could decay and emit photons of lower energy in the aftermath.

The question is: are those photons still the same as the photon that started the whole shabang? If you shine a uv laser at a whiteboard marker that clearly converts those 405 nm photons in 500 nm-ish ones without a hitch. But what really happens is that the dye absorbs the 405nm one and emits a -different- photon of lower energy.

The problem is that photons are not like basketballs that can be shown to be the same basketball even after it slowed down due impact with your head. Photons only have only two real properties: momentum (wave vector) and polarization. You can see the momentum as a combination of the energy and the direction of travel. They don't have 'hair' otherwise, and telling one from another is impossible.
 
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I agree with that and I think I have learned a bit form this topic thanks :p Its nice to have conversations about this, try talking to my buds about lasers or physics and they just kinda want you to stop, so its hard to find folks that find the same topics interesting:tinfoil: Our world view is important to me even if my rl friends find it trivial. I am not doing to bad for someone that dropped out in 10th grade to do to work, and has spend 23 years out of school :D
 

Benm

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Dont worry too much about time spent it school. A grasp for these (weird) concepts mostly comes naturally to you, or it doesnt. Downside is that there is always an even deeper level of understanding to it that remains to be investigated ;)

I suppose most people have little interest in understanding at all though, since real world application in daily life is rare.
 
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I suppose most people have little interest in understanding at all though, since real world application in daily life is rare.

What? Don't you ever get struck to the ground as photons from the sun strike the very moment you step outside?

It keeps happening to me.
 
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haha what i dont understand is how its actually an electro-magnetic force. how its a wave form in one...polarization, for lack of better words, at the electron wave, and another polarization in the magnetic wave, and how when it moves, one stops existing at a point the other still is, but it comes out of zero on the wave and makes another peak. and to increase the energy, say from 20k nm to 100nm what actually increases? the frequency of electron wave, or magnetic wave? both?

i agree reddish, the only person i can converse with this stuff is with my roommates dad. hes all about physics, rc helis and gliders, how the brain works, how you dont actually see light, feel surfaces, hear things, its all recorded data on your brain taught and learned by past experiences.
 

Benm

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What? Don't you ever get struck to the ground as photons from the sun strike the very moment you step outside?

It keeps happening to me.

Goth is a chosen lifestyle, not a phenomenon of physics :D
 




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