When matter and anti-matter collide, in what form is the resulting energy?

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Discussion Overview

The discussion revolves around the nature of energy produced when matter and antimatter collide, specifically focusing on the forms of energy resulting from such annihilation events. Participants explore theoretical implications, potential processes for energy conversion, and the conditions required for these phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that the annihilation of matter and antimatter results in high-energy photons, which are described as having zero mass and can be considered "pure energy."
  • There is a discussion about whether the energy produced can be classified as light or if it manifests in other forms, with a participant questioning the nature of energy in the absence of matter.
  • One participant suggests the possibility of reversing the annihilation process by focusing high-energy photons to create an electron-positron pair, raising questions about the feasibility of such a process.
  • Another participant clarifies that gamma rays are a type of photon with high frequency and discusses the conditions under which photons can create electron-positron pairs, emphasizing the need for high-energy photons and the presence of a nucleus to conserve momentum.

Areas of Agreement / Disagreement

Participants generally agree that high-energy photons result from matter-antimatter annihilation, but there is no consensus on the practicality of reversing the process to create matter from energy, as well as the specific conditions required for such phenomena.

Contextual Notes

The discussion includes assumptions about the energy levels required for photon interactions and the role of nuclei in the creation of particle pairs, which remain unresolved. The practicality of focusing high-energy photons to achieve the desired outcomes is also uncertain.

Who May Find This Useful

This discussion may be of interest to those studying particle physics, energy conversion processes, and the interactions between matter and antimatter.

Jarfi
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I know that when matter is mixed with anti matter they disappear into pure energy. But how can there be energy with no matter? Is it light that forms? do we get a massive blast of light? what else could it be? with no matter you can't have energy(exept for light)... what happens?
 
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Your guess is right, when particles annihilate with antiparticles the result is high-energy photons, which have zero mass so they can be said to be "pure energy". Also note that while electrons and positrons convert entirely to photons, the same is not true for protons and antiprotons, see the second paragraph here.
 
Last edited:
JesseM said:
Your guess is right, when particles annihilate with antiparticles the result is high-energy photons, which have zero mass so they can be said to be "pure energy". here.


So if electrons and positrons create photons and gamma rays. Could i reverse the process and focus light/gamma rays in one dot and end up with an electron and positron?
 
Jarfi said:
So if electrons and positrons create photons and gamma rays.
gamma ray is just a name for the type of photons emitted (a gamma ray is just a photon with a sufficiently high frequency, see the electromagnetic spectrum), they aren't two different types of particles.
Jarfi said:
Could i reverse the process and focus light/gamma rays in one dot and end up with an electron and positron?
A pair of gamma ray photons can spontaneously create an electron/positron pair (see 'reverse reaction'), I don't know how difficult it is to produce photons with such high energy or the probability they will convert in this way if focused at a sufficiently small region or how difficult it would be to actually focus high-energy photons in this way, maybe someone else can address the practicality of this.
 
Single photon gamma rays with energy above 1.022 Mev may end up as an electron-positron pair. This can only occur in the presence of a nucleus, needed to conserve momentum. This process is one of the principal ways to shield (using lead for example) against high energy gamma rays.
 

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