Can a photon be emitted without a receiver?

Enos Oye

A photon or electromagnetic wave has the speed of light in vacuum and the distance, from the photons point of view, then becomes zero.

The photon is then an energy exchange between particle A and particle B, and it is from the photons view at startpoint A and endpoint B at the same time. And it has to be connected to the startpoint A and endpoint B at the same time. If there is no endpoint B, there is no connection and no photon.

Then the photon is a continuous electromagnetic wave between two particles, transferring energy and information. And photons can’t be emitted randomly into empty space, but has to have a receiver. Like a plasma particle, planet, a star etc.

Is this logically valid?

I guess this is a far better version of, if a tree falls in the forest and there is no one around to hear it, does it then make a sound? And I just can’t disprove this version, can you?

kevinferreira

Photons can be emitted without a receiver, for example by accelerating charged particles or when an electron changes level in an atom. The photon is just emitted, not between any two particles, it is just created, 'randomly into empty space' as you said.

Enos Oye

You may be right, but you only come with statements, and we need arguments to solve the question: Can photons be emitted without a receiver?

I also see some similarities to quantum physics, where the measurement itself can change the result and decide where the observed particle will be.

Drakkith

It is an observed fact that energy is carried away from a transmitter by EM waves. These waves then radiate outwards where they may or may not interact with something. The key here is that the energy is gone from the transmitter and exists as the EM wave for some length of time before being deposited into matter when it interacts with something. IF it interacts at all of course. Nothing says that it MUST interact, and indeed there may be photons that have been emitted and will never interact with matter. Since, as far as we know, information only travels at c, the photons cannot know if there will be an receiver to interact with before emission, so I would say that yes, they can be emitted without a receiver.

The photon does not have a point of view. You cannot assign a frame of reference to it.

No, as photons are the result of a quantized interaction of an EM wave with matter. They are not continuous EM waves.

kevinferreira

I don't need arguments, I was trying to explain that nature gives the answer to your question: yes.
Now, I define "receiver" as an object of whatever nature that is sensible to interacting with a photon. As drakkith stated, this potential further interaction, i.e. the existence or not of a receiver, is not at all needed to understand the interaction itself.
Photons as quanta of the electromagnetic field are perfectly understood in our theories as existing by themselves, even if they are the electromagnetic force carriers (gauge fields), and no 'further interaction' is needed: it may or not happen, but it does not define the nature of the photon field.

harrylin

The laws of nature as we know and tested until now, have that a falling tree makes sound and that a light emits EM waves (photons) independent of the presence of receivers.

As a logical argument: receivers can be added and removed during the time that the waves propagate, so that nature cannot "know" if the photons will ever be received. (Oh I see that Drakkith already gave the same argument)

ZapperZ

This is one of my example of a "So when did you stop beating your wife?" question. Why? It presumes a scenario, and then uses it to extrapolate into something else, without checking first of all if the original scenario is even valid.

If you look in the Relativity FAQ subforum, you'll find an entry on why transforming to the photon reference frame is not valid. So the argument being used "from the photon view" is highly dubious, which makes subsequent deduction based on this to be incorrect. It also makes any discussion on the result to be rather moot.

Zz.

DaleSpam

Hi Enos Oye, this seems like it may be personal speculation. The purpose of PF is not to prove or disprove people's personal speculations, but to help people learn mainstream science.

Do you have a mainstream scientific reference for this concept that we can use as the basis of discussion? Otherwise, instead of making speculative statements about photons, could you instead ask questions about the mainstream view of photon emission?

Naty1

well, no.
This would mean, for example, that cosmic micowave background radiation,CMBR, which has taken about 13.4Billion years to reach us [from the end of the inflationary era] arrived here instantaneously. That's not what we observe.

We also observe a redshift of the CMBR by a factor of about 1090 [= z] which has cooled from almost 3000 degrees K to about 2.73 degrees K today. IF it arrived instantaneously we'd never even be here because the cosmos would still be at nearly 3000 degrees K and nothing would have formed to sustain any life.

Naty1

Sure; for example the CMBR that reaches us has been travelling for 13.4B years without being 'received' until it reaches earth; most misses planets,stars, galaxies and continues on its way through the cosmic void.

andrien

This is really a good question and so far the answer is not satisfactory.http://en.wikipedia.org/wiki/Wheeler...bsorber_theory

Enos Oye

I only asked a simple question, isn't that allowed in this forum?
If you are frustrated I can relate to that, because I just can't settle the answer of this simple question: Can a photon be emitted without a receiver?

ZapperZ

There's a difference between "asking a simple question" versus "I'm going to adopt a faulty scenario, and then USE that to justify other things".

You did not seem to make any effort to learn why transforming to the photon frame is not valid, even though you were told where to look for such information. This is not a sign of someone who wishes to learn!

Yes.

Is that a simple enough answer for your simple question?

Zz.

Vanadium 50

This is turning into a weird mix of personal theory and the "tree fall in the forest" problem in philosophy. It doesn't belong here. Thread closed.