Where does the photon live

  • Thread starter QuantumHop
  • Start date
  • #1
68
0

Main Question or Discussion Point

Where does the photon "live"

What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?

How is it waving in our reference frame?

We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field!! change requires time. Does this mean its both waves at once until we observe it?

When photons are created they radiate outwards as a wave but it can only be detected at one point in space, this is also crazy because it would suggest that if you were in a room with a light bulb and you put a photon detector at any point in the room it should absorbed all the photons leaving the rest of the room dark.

If the laws of nature have courts then the photon should stand trial for giving me headaches.
 

Answers and Replies

  • #2
jtbell
Mentor
15,544
3,453
Last edited:
  • #3
68
0


There is no such frame. There is no inertial reference frame in which a photon or electromagnetic wave is at rest. It's a self-contratictory concept.

https://www.physicsforums.com/showthread.php?t=511170
Thanks for the link, I'm sure the answer to my question is in there but I still don't get it.
If its still moving at speed c in its reference frame then how come its not experiencing time? how can it be in motion and yet not experience time when motion requires time.
 
  • #4
5,428
291


QuantumHop said:
We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field!!
I don't think there's anything to support this view. The two fields are in phase but perpendicular. You might just as easily say that the magnetic component creates the electric field.

See the Wiki article http://en.wikipedia.org/wiki/Electromagnetic_radiation
 
  • #5
1,352
90


What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?

How is it waving in our reference frame?

We observe an electric field that creates a magnetic field and so it propagates as a wave, but in its frame there is no time and without time an electric field cannot create a magnetic field!! change requires time. Does this mean its both waves at once until we observe it?

When photons are created they radiate outwards as a wave but it can only be detected at one point in space, this is also crazy because it would suggest that if you were in a room with a light bulb and you put a photon detector at any point in the room it should absorbed all the photons leaving the rest of the room dark.

If the laws of nature have courts then the photon should stand trial for giving me headaches.
I hear ya,

perhaps the photon asks the same for something that doesn't have to move at c. It's equally odd isn't? The photon wonders how we include time in our observations of it.

The last paragraph is ignoring quanta of EM isn't?
 
  • #6
3,872
88


What happens to space-time when you remove the time?[..]
A universe without time is mere speculation. - it isn't realistic at all.
 
  • #7
ghwellsjr
Science Advisor
Gold Member
5,122
146


There is no such frame. There is no inertial reference frame in which a photon or electromagnetic wave is at rest. It's a self-contradictory concept.

https://www.physicsforums.com/showthread.php?t=511170
Thanks for the link, I'm sure the answer to my question is in there but I still don't get it.
If its still moving at speed c in its reference frame then how come its not experiencing time? how can it be in motion and yet not experience time when motion requires time.
Why, after jtbell told you, there is no reference frame for a photon, do you quote him and then ignore him by repeating the same self-contradictory question?

Before you can ask meaningful questions about a reference frame, you need to learn and understand what it is and how it is defined. Part of that definition requires clocks at rest at different locations in that reference frame. You cannot build a clock out of just photons, you need massive particles which cannot travel at c. Therefore, the definition of a reference frame is meaningless for a photon.

The definition of a reference frame also requires the use of a rigid ruler which also requires massive particles. You cannot build a ruler out of just photons. Therefore, your first question, "What happens to space-time when you remove the time?", when applied to a photon should more appropriately be "What happens to space-time when you remove the space and the time?" Do you see how meaningless it gets?

It's not that "the photon experiences no time", it's that the photon has no experience. You need to learn what a reference frame is and how it is used in Special Relativity before this will make sense to you.
 
  • #8
29,281
5,595


If its still moving at speed c in its reference frame then how come its not experiencing time?
It is NOT moving at c in "its reference frame", there is simply no such frame which can be called "its reference frame".
 
  • #9
441
8


What happens to space-time when you remove the time?

Its said that the photon experiences no time, it seems to be generally accepted that a photon is emitted by one atom and then instantly absorbed by another in its reference frame but this seems paradoxical. If it was emitted by an atom and then never experienced time it would exist forever. The very fact it is created and then destroyed suggests it must experience time. Is it that the distance between the atom that emits it and the atom that absorbs it is zero or does it occupy all of "space?" until its absorbed?
Particles and light don't experience time. When an electron absorbs a photon, it's always the first time, i.e. it has no memory. People have memories, they track time.
 

Related Threads on Where does the photon live

  • Last Post
Replies
11
Views
4K
  • Last Post
Replies
19
Views
4K
Replies
23
Views
16K
Replies
11
Views
2K
Replies
4
Views
2K
  • Last Post
Replies
8
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
10
Views
2K
Replies
2
Views
1K
  • Last Post
Replies
2
Views
2K
Top