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Author Topic: Would the photon lose all its energy at infinity?  (Read 69351 times)

Offline JohnDuffield

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Re: Would the photon lose all its energy at infinity?
« Reply #150 on: 01/03/2015 17:17:29 »
So is it a yes the photon does lose all its energy at infinity or a no?
It's a no. The ascending photon doesn't lose any energy. It takes energy to lift you up, so the selfsame E=hf photon appears to have lost energy, when in fact, you've gained it. It's similar to what happens in gravity-free space when you accelerate away from a light source.

As to whether the CMBR photons have lost energy is another matter. I think the answer is no, but I can't be so confident about that. Things like the big bang and the early universe are tricky. In comparison, gravity is straightforward. Or ought to be.   
 

Offline yor_on

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Re: Would the photon lose all its energy at infinity?
« Reply #151 on: 01/03/2015 17:28:17 »
Get confused reading this David, are you associating a photon with a notes frequency? Then stating that dark energy interact with it? The note solely, or both note and photon? If you're thinking of gravitational red/blueshifts, assuming that dark energy interact through that, then that is observer dependent, and not about a photon 'energy'  intrinsically, as far as I know?

"This reduction in the frequency you hear will become closer and closer to zero though (meaning the note doesn't appear to get much flatter at all) and the change will soon become impossible to measure - the strongest effect is deep down in the well, but once out in deep space you are in practical terms no longer in that well, even though you technically still are.

However, the frequency could still be reduced to zero over infinite distance because of dark energy and the expansion of space."
=

Let us assume that dark energy 'pushes' material bodies away from each other 'gravitationally'. Either you then have to define it to only existing outside/between galaxies, or explain how this new source of gravity interact inside solar systems, galaxies with the one we're accustomed to define. So now we have a unknown source of gravitation between galaxies, defining a redshift. But then it's not about a 'expanding space', it's just assembly's of 'bodies' separating from each other in a vacuum, in which case the redshift from a expansion becomes observer dependent again. But it leaves us to explain why this dark energy won't interact inside galaxies, solar systems etc, if so. Because that gravitational influence should be measurable. If we define the universe as infinite then it is a possible mechanism, although? Why only in between?

(also, such a behavior would separate a accelerating expansion from a inflations, that is unless we assume a vacuum to 'preexist', which is a interesting idea. You could then turn it around to a vacuum being the result of the distribution of matter, starting as some regime of 'temperature/energy'. Still needing it to be diffused though, linking itself into a 'common universe' becoming a 'inflationary period', as the cosmic 'light-sphere of age' we observe is presumed to be found no matter where you go)

The idea behind it, as I understand it, is that it is 'spread out' and 'diffused' everywhere, only becoming a 'strong negative force' over large distances counteracting gravity. Either as some wave building up from smaller 'pushing' galaxies apart, or as I think about it, as some 'upwelling' in each 'point' of a vacuum. If it was as a wave, you need to explain how it can 'push away' in all directions, using a 'upwelling' makes it a little easier to think about it, but not much :)
« Last Edit: 01/03/2015 19:05:37 by yor_on »
 

Offline David Cooper

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Re: Would the photon lose all its energy at infinity?
« Reply #152 on: 01/03/2015 20:34:42 »
Get confused reading this David, are you associating a photon with a notes frequency? Then stating that dark energy interact with it? The note solely, or both note and photon? If you're thinking of gravitational red/blueshifts, assuming that dark energy interact through that, then that is observer dependent, and not about a photon 'energy'  intrinsically, as far as I know?

I mentioned dark energy solely because I think that's were the confusion comes from - we see that the radiation from the big bang is of lower frequency than it must have set out with, and we predict that it will continue to be measured as having progressively lower energy over tens of billions of years to come, and infinite expansion would lead to infinite energy loss. This idea about photons losing energy can then potentially get tangled up in people's minds when they think about photons climbing out of gravity wells too, thereby leading to them thinking there is loss of enegy there as well, but there isn't - it isn't possible to change a frequency of anything if it travels between two points which remain a constant distance apart (unless they're both accelerating, or you lengthen the communication path in some other way or ramp up some other delay mechanism within it), and the energy of light is entirely wrapped up in its frequency, so it cannot be losing any energy if the frequency is unchanged. All that actually changes is the frequency that is produced when a device operates at different depths in a gravity well - the deeper it is, the lower the generated frequency will be, though from the point of view of the device it is producing exactly the same frequency on each occasion, and any device designed to measure the frequency locally would agree with it.

I used the musical note example because it allows you to see the movement of the string from far away and to see the frequency of the actual oscillation that produced the note. The situation is the same with sound and photon frequency, so it's a useful parallel. The note will get quieter over distance just as a beam of light will spread out and become dimmer, but the frequency is a constant in each case. The big difference is that sound travels more slowly, but we get the same apparent frequency reduction with it over the same change in altitude within the gravity well because the effect is entirely driven by time dilation. If we use an analogue radio communication to send the sound up from ground level to the top of the towerblock at the speed of light we will have the exact same reduction in the frequency of the note measured up there. (With a digital radio communication though, we would not hear the note flatten, but there would be occasional breaks in the stream instead.)

The other case worth thinking about is the light escaping from a black hole. If it comes from just outside the event horizon, there are different scenarios to consider which relate to how it is produced. If it comes from something that is stationary relative to the event horizon, time dilation will be so extreme that the photon will be generated at such a low frequency that I don't know if it would even be classed as a radio wave, but if you viewed it from where it was produced you would see it as light. By the time that photon has climbed up into deep space, it would be detected as having the extremely low frequency that it was actually produced with. Alternatively, if the photon came from some object that was racing into the black hole, and if it (the photon) was released just outside the event horizon, time dilation would not be so severe [take this bit with a pinch of salt - I'm taking that on trust from leading scientists in TV documentaries, but they often simplify the truth out of things and end up misleading people instead of informing them], so the light could be produced at a higher frequency, but the object's movement inwards during the production of the photon would spread the photon out and give it no higher effective frequency than the photon released from a stationary object hovering just outside the event horizon.

If we want to try releasing a photon from the event horizon itself, then an object suspended there would be completely frozen in time and could not produce a photon of greater frequency than zero, but an object falling in still could [repeat dose of a pinch of salt here]. In this case, the photon is going to have a frequency, but it will again be spread out, and either it will have the back end ripped into the black hole (thereby producing an effective frequency of zero) or the photon may just escape with next to no frequency, and it will be impossible to detect by the time it has reached deep space.

If a photon is released any distance inside the event horizon, it's impossible for it to be released from a stationary object, so there's only one case to consider, that being that it is being emitted from an object which is moving deeper into the black hole. In this case, the photon may be produced at a reasonable frequency [more salt required here], but it will be dragged backwards into the black hole and will therefore have no effective frequency at all from the point of view of an outside observer.
 

Offline yor_on

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Re: Would the photon lose all its energy at infinity?
« Reply #153 on: 02/03/2015 15:16:59 »
It depends. Discussing event horizons, apparent or not, is a headache. If we keep it simple it's just a matter of frames of reference, each 'frame' observing the other using its own clock and ruler. Each frame being correct in its view of a universe. If you define 'c' as equivalent to your local 'clock' then there is nowhere 'time freezes up' for you. and that goes for both frames of reference.
=

I split the idea of lights duality from this. Using a field(s) is a very simple idea actually, naively, ignoring observer dependencies, but it wrecks havoc with our ideas of a propagation, unless you presume a wave universe as where this is coming from. Doing so you now place the idea of a quanta as a secondary effect, which it is not, if you consider it in terms of scaling 'down under'. Myself I define this universe from 'quanta', waves and a duality being a complementary description. Waves was the first one we found, and it explained a lot to us, then Einstein had the temerity to come and destroy it (black body radiation:)
=

It is possible to think of it this way, maybe? If there is discrete quanta, then they are not 'observer dependent', and what we define as observer dependent, when it comes to a clock and ruler, then becomes a result of the scales we use. That doesn't state that they are illusions. A illusion should be something you don't find to work, ah well, changing frame of reference to what you measured as being 'different' you then will be 'synchronized' with it :) So was it illusionary? In terms of your life span, not locally it was, but 'unifying the container' it becomes so. So strictly speaking, where was it you said you lived?

you only need waves when you want to connect it into what I call a 'commonly agreed on universe', that's also a container and a idea of something more needed to 'unify it'. Locally defined quanta works just fine I think. As do probability and statistics.
=

A simple definition of the difference might be to think of a wave universe versus a 'quanta universe'. That's two different 'directions' in my mind. One is waves and light propagating in a container. The other is scaling.
=

the question is how to get those two to agree with each other, scaling versus a container. You need something describing what we see. I think we will find it, but it will build on scaling.
« Last Edit: 02/03/2015 16:57:47 by yor_on »
 

Offline Ethos_

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Re: Would the photon lose all its energy at infinity?
« Reply #154 on: 03/03/2015 15:41:26 »
maybe photonists soon will be selling sneakoil?
Yet more experimentally factual and effective than the "snakeoil" you're peddling.
 

Offline Ethos_

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Re: Would the photon lose all its energy at infinity?
« Reply #155 on: 03/03/2015 15:45:01 »
i am a college fall out, my theory is not. no?
It might have been a wise move if you had stayed in college.
 

Offline Robbo

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Re: Would the photon lose all its energy at infinity?
« Reply #156 on: 07/03/2015 18:57:12 »
this forum deleted some of my postings

maybe soon will ban my account

i recorded everything i posted

find true science at fuckedscience.com

if you see me here no more

I joined this forum last week and I have to say the most amazing thing I've encountered thus far aren't the dark mysteries of a black hole, or indeed the jaw-drop lunacy of Quantum Mechanics ... it is this thread.
I have a sports forum and so I'm well used to all types of contributor that a forum attracts - from the curious, to the arrogant, to the downright ignorant and to the disgustingly enlightened, all of whom just love to express their opinion in true Orwellian style.'

And with that thought sloshing around in my head, it reminded me of something my father once told me, 'You can deal with politicians, you can deal with bigots, you can deal with criminals and even terrorists but you cannot deal with an idiot'

This thread pays testament to the endless patience a lot of you guys have displayed while dealing with someone who's either being deliberately obtuse, or is just plain incapable of assimilating a whole slew of lucid clarifications that you guys have been kind enough to post in the somewhat vain hope of helping him.
At times, his posts have been disrespectful, impolite and on many occasions, inappropriately dismissive.
A lot of you guys deserve a virtual medal for such courtesy because I think most people would have reacted quite quickly to his attitude.
I apologise if I've offended anybody, it wasn't my intent - I was merely making an observation.
I'm extremely impressed with such a tolerant bunch of guys .. if only my forum could boast such a demographic :/
« Last Edit: 07/03/2015 19:04:15 by Robbo »
 

Offline Ethos_

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Re: Would the photon lose all its energy at infinity?
« Reply #157 on: 07/03/2015 21:35:30 »
break my legs if you want to, i am not leaving this place.
It might have been more accurate to say: "I am not voluntarily leaving this place. Time will tell as to the alternate remedy.
« Last Edit: 07/03/2015 21:37:35 by Ethos_ »
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #158 on: 15/03/2015 08:16:41 »
it was a long discussing, maybe we should make sure if photon is a real thing or not now.

should we start a poll?

 

Offline jeffreyH

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Re: Would the photon lose all its energy at infinity?
« Reply #159 on: 16/03/2015 00:33:22 »
Just look around you. Is it dark?
 

Offline Ethos_

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Re: Would the photon lose all its energy at infinity?
« Reply #160 on: 16/03/2015 01:35:40 »
Just look around you. Is it dark?
There is none so blind as he who will not see.
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #161 on: 17/03/2015 19:18:15 »
if energy is conserve, matter is conserve, charge is conserve.

how could electron emits photons? how many rounds of photon can an electron carry?

if photon is a real thing, when it passes water, it slows down, lose some energy, than comes out water, how could it gain energy and move faster?

energy exchange? how?

what's the difference between a green photon and a red photon? red light vibrates 4.2X10^14 times per second, it that mean red photon passes a single point 4.2x10^14 times? an electron emits 4.2x10^14 photons per second?

if light is gravitational wave produced by exited atoms, it is a force pause that acts on any matter on the way/field.

if a matter vibrates, its gravitational force vibrates, propagates at c.

thoughts?
 

Offline chiralSPO

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Re: Would the photon lose all its energy at infinity?
« Reply #162 on: 17/03/2015 20:00:35 »
if energy is conserve, matter is conserve, charge is conserve.

how could electron emits photons? how many rounds of photon can an electron carry?

This is a good question. I don't know exactly how this works, and I am not entirely satisfied with any of the answers I have heard on this one yet...

if photon is a real thing, when it passes water, it slows down, lose some energy, than comes out water, how could it gain energy and move faster?

Because the photon has zero rest mass its energy and speed are unrelated. It does not lose energy as it slows down, or when it speeds back up. The energy is related to the frequency of the photon which is unchanged by this interaction.


what's the difference between a green photon and a red photon? red light vibrates 4.2X10^14 times per second, it that mean red photon passes a single point 4.2x10^14 times? an electron emits 4.2x10^14 photons per second?


No, electrons do not emit 4.2x10^14 photons per second. This is the frequency of the  electromagnetic wave associated with the photon.
 

Offline evan_au

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Re: Would the photon lose all its energy at infinity?
« Reply #163 on: 17/03/2015 20:48:03 »
Quote from: jccc
how many rounds of photon can an electron carry?
An electron (or proton) does not "carry" any photons when it is traveling through free space.
  • However, an electron (or proton) which is accelerated by some means does emit electromagnetic radiation (photons).
  • So you do not want to be in the tunnel of the LHC when the beam is on, because the acceleration of the protons to bend them around in a circle emits intense X-Rays which would not be therapeutic.
  • Similarly, a hot plasma in the Sun or in a hydrogen fusion reactor consists of protons and electrons flying around separately, at high velocity. However, if an electron approaches a proton, the electric field between them accelerates the electron, changing it's speed & direction and emitting photons. But because the speed is so high (due to high temperature), the proton can't hold on to the electron, and they continue their separate ways. 

In empty space, an electron and proton which are far apart (physicists say "at infinity") will be attracted to each other and approach. The electron is likely to be captured by the proton, forming a hydrogen atom.
  • The electron could fall straight to the lowest level (n=1), emitting a single ultraviolet photon with a wavelength of 91.2 nm. This is part of the Lyman series. Look at the line in the table labelled with "∞".
  • Or, the electron could fall into the third-lowest level (n=3), emitting a single infra-red photon with a wavelength of 820nm (Paschen Series). This could be followed by a cascade down to the second level (n=2, Balmer Series), emitting a single red photon of 656nm. This could then fall to the lowest level (n=1), emitting an ultraviolet photon of 121nm (from the Lyman series).
  • Note that the total energy of the 3 photons is the same as the energy of the single photon emitted when the electron falls straight to the ground state.
  • There are an infinite number of orbitals that the electron could fall into. Each one has its own characteristic energy level, and will emit a photon of a specific frequency and energy when transitioning to another level (although many of the energy levels are so close together that you can't easily distinguish them). This shows up in the spectrum of a Hydrogen atom, which has an infinite number of lines in it. 
So in theory, you could have an electron emitting a huge ("infinite") number of photons, each of very long wavelength as it falls towards the proton. But the total energy of all these photons is the same as a 91.2nm photon (ie energy is conserved).
« Last Edit: 18/03/2015 10:21:53 by evan_au »
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #164 on: 17/03/2015 21:53:47 »
if you make a 3 d model of an atom, a center piece, few energy levels, orbital shells, and an electron, you need a few legs to support the energy levels, or orbitals, you need something to support the electron, so everything has its position.

now you only have 1 proton and 1 electron, how you build that atom as science said?

how a photon interacts with an atom? contact act? force act? which particle act with photon? what's the mechanism?
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #165 on: 17/03/2015 22:26:07 »
when a charge is vibrating, its em force follows. the charge emits em wave.

when a mass is vibrating, its gravitational force is vibrating, the mass emits gravitational wave.

when an atom vibrates at 10^14 or so per second, it emits visible light.

seems all correct?

 

Offline PmbPhy

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Re: Would the photon lose all its energy at infinity?
« Reply #166 on: 19/03/2015 05:47:37 »
it was a long discussing, maybe we should make sure if photon is a real thing or not now.

should we start a poll?
Poll on what? If its a poll about who wants you to be here then that's simple. Nobody wants you to be here.
 

Offline PmbPhy

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Re: Would the photon lose all its energy at infinity?
« Reply #167 on: 19/03/2015 06:05:22 »
Quote from: jccc
if energy is conserve, matter is conserve, charge is conserve.
So what? Those are independent laws of nature except for conservation of matter. There is no such law. Relativity proved that to be wrong. Conservation of charge cannot be derived from conservation of energy.

Why do you waste space and people's time with this nonsense?

Quote from: jccc
how could electron emits photons?
Study quantum mechanics, particle physics and field theory and you'll learn how.

Quote from: jccc
how many rounds of photon can an electron carry?
False notion. But to be expected from jccc.

Quote from: jccc
what's the difference between a green photon and a red photon? red light vibrates 4.2X10^14 times per second, it that mean red photon passes a single point 4.2x10^14 times? an electron emits 4.2x10^14 photons per second?
Of course not. The energy and momentum is a function of frequency. That's part of its meaning. Another part is that it's related to wavelength and that's part of its meaning, i.e. wave properties. To understand the last  part then one has to understand what a phasor is, and you don't know what that is because you keep ignoring everyone's suggestion to study math and physics. The phasor can be thought of as a rotating arrow and that rotating arrow can be used to visualize how wave functions add up.  Feynman does this in his book QED (although he doesn't tell the reader that he's talking about phasors.

Quote from: jccc
if light is gravitational wave...
Utter garbage!

Quote from: jccc
thoughts?
Yes. Please leave us in peace.
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #168 on: 19/03/2015 12:31:25 »
if you make a 3 d model of an atom, a center piece, few energy levels, orbital shells, and an electron, you need a few legs to support the energy levels, or orbitals, you need something to support the electron, so everything has its position.

now you only have 1 proton and 1 electron, how you build that atom as science said?

how a photon interacts with an atom? contact act? force act? which particle act with photon? what's the mechanism?

debunk this?
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #169 on: 19/03/2015 12:32:35 »
when a charge is vibrating, its em force follows. the charge emits em wave.

when a mass is vibrating, its gravitational force is vibrating, the mass emits gravitational wave.

when an atom vibrates at 10^14 or so per second, it emits visible light.

seems all correct?

and this.

please don't delete my comment again, is this an open forum?
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #170 on: 19/03/2015 12:43:37 »
maybe photonists soon will be selling sneakoil?
Yet more experimentally factual and effective than the "snakeoil" you're peddling.

this is mainstream science 

this is my science 

you be the judge.
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #171 on: 20/03/2015 02:25:11 »
nature science
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #172 on: 20/03/2015 03:51:19 »
he has a diamond ring on his right arm!
 

Offline JohnDuffield

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Re: Would the photon lose all its energy at infinity?
« Reply #173 on: 20/03/2015 17:45:10 »
This is a good question. I don't know exactly how this works, and I am not entirely satisfied with any of the answers I have heard on this one yet...
Remember that you can make an electron (and a positron) out of a photon in pair production. Draw a circle on a piece of paper to emulate the electron, then without lifting your pen, draw another circle on top of the first, and another, and another. You are emulating electron spin. Now think about Compton scattering wherein the electron absorbs part of the photon, and as a result, moves. To emulate the moving electron with a smaller Compton wavelength draw an incomplete circle, then without lifting your pen, draw another incomplete circle, and another, and another.
 

Offline jccc

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Re: Would the photon lose all its energy at infinity?
« Reply #174 on: 20/03/2015 20:22:36 »
if you don't believe virgin can give birth, how could you believe electron able to emit photon?

all things must have precise mechanism, that's how physics law works.

can you build a car with 90% parts? write a program with 90% codes?

fundamental physics MUST be 100% accurate.
 

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Re: Would the photon lose all its energy at infinity?
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