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Author Topic: Is there an antimatter equivalent for light?  (Read 5144 times)

Aris

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Is there an antimatter equivalent for light?
« on: 17/12/2008 20:40:12 »
Ali & Steve  asked the Naked Scientists:

Could there be an antimatter equivalent to light

it makes sense that the positron  would set up an electric field/magnetic field as it moved from one level of excitement to another  just as an electron does but the radiation would have it's poles reversed?

It should also annihilate normal light?

Steve Thompson
Lankeys Creek
Australia

What do you think?


 

Offline Soul Surfer

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Is there an antimatter equivalent for light?
« Reply #1 on: 17/12/2008 23:01:35 »
yes the antimatter equivalent of light is light a photon is its own antiparticle  (this is not the only case of this in quantum mecanics)it is quite possible for one photon to cancel out another. you see this effectively where you get destructive interference.

However thats not quite the full story because photons are always on the move and unless these photons are carefully aligned so that they always cancel this anhilation will only happen briefly at one instant of time
 

Offline LeeE

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Is there an antimatter equivalent for light?
« Reply #2 on: 19/12/2008 00:52:49 »
Dark energy, if it exists, would be the antimatter equivalent to light.  Photons are regarded as their own anti-particles but this only applies to their phase, and two anti-phase photons will not annihilate each other (the product of which would be photons), but will only cancel each other at the point of collision.  The photons will carry on afterwards, as before the collision, with no loss of energy.

Light is not matter, and trying to relate anti-matter properties to something that is not matter doesn't work.
 

Offline DoctorBeaver

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Is there an antimatter equivalent for light?
« Reply #3 on: 19/12/2008 09:15:06 »
Dark energy, if it exists, would be the antimatter equivalent to light.

Can you explain your reasoning behind that? The only thing I can think of is that "dark" is the opposite of "light"; but that is just terminology. I'm sure an intellect such as you possess would not make such a spurious connection except in jest.
 

Offline lightarrow

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Is there an antimatter equivalent for light?
« Reply #4 on: 19/12/2008 12:53:57 »
<<it makes sense that the positron  would set up an electric field/magnetic field as it moved from one level of excitement to another  just as an electron does but the radiation would have it's poles reversed?
It should also annihilate normal light?>>

a positive charge's motion generates the same electromagnetic radiation generated by a negative charge's motion.
 

Offline LeeE

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Is there an antimatter equivalent for light?
« Reply #5 on: 19/12/2008 14:23:58 »
DrB - that's not an assertion of any authority.  Heh - any assertion that invokes Dark Energy is speculation but some scientists believe that DE may effectively be negative energy.

Can't quite get my head around it, personally.

My intellect is old and knackered, and I'd rather you didn't draw attention to it.
 

lyner

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Is there an antimatter equivalent for light?
« Reply #6 on: 19/12/2008 19:53:34 »
yes the antimatter equivalent of light is light a photon is its own antiparticle  (this is not the only case of this in quantum mecanics)it is quite possible for one photon to cancel out another. you see this effectively where you get destructive interference.

However thats not quite the full story because photons are always on the move and unless these photons are carefully aligned so that they always cancel this anhilation will only happen briefly at one instant of time
I would take issue with your idea of photons 'annihilating' each other.
Waves may add constructively or destructively but the photons, if you insist on including them in this particular part of the process, are merely re-directed away from some parts of the diffraction pattern (troughs) and directed to others (peaks).

Uncertainty cannot allow you to specify the phase, frequency and position of two photons and predict how they will 'affect each other'.

Why oh why do people have to keep the 'little bullet' picture of photons in their minds. It is such a fraught concept. Stick to waves because they will tell you what will happen on the journey. Photons will help to describe the interaction. The small thing about a photon is its energy - its 'size' is not relevant (or even meaningful, I believe) to understanding and predicting what goes on.
 

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Is there an antimatter equivalent for light?
« Reply #6 on: 19/12/2008 19:53:34 »

 

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