Antimatter and matter canceling out

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    Antimatter Matter
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Discussion Overview

The discussion revolves around the concepts of antimatter, matter annihilation, and the conservation of energy. Participants explore the implications of matter and antimatter interactions, specifically addressing the processes involved and the conditions under which these interactions occur.

Discussion Character

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

Main Points Raised

  • Some participants propose that antimatter and matter "cancel each other out," while others clarify that this process is known as "annihilation," which results in the creation of other particles and/or electromagnetic radiation.
  • There is a discussion about whether annihilation contradicts the law of conservation of energy, with some asserting that energy and mass are conserved through the creation of new particles and radiation.
  • Participants mention the misconception that antimatter consists of negative mass and suggest that further reading is necessary to understand the concept fully.
  • Questions arise about the possibility of photons converting back into matter, with references to "pair production" as a process where energetic photons can create electron-positron pairs in the presence of a heavy nucleus.
  • There is a discussion about the dynamics between positrons and electrons, particularly regarding their potential to annihilate each other or to escape each other due to sufficient kinetic energy.

Areas of Agreement / Disagreement

Participants express differing views on the terminology and implications of matter-antimatter interactions, with some agreeing on the conservation of energy while others raise questions about the processes involved. The discussion remains unresolved regarding the nuances of these interactions.

Contextual Notes

Some statements rely on assumptions about energy conservation and the conditions necessary for pair production, which may not be universally agreed upon. The discussion includes various interpretations of the processes involved in matter-antimatter interactions.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in particle physics, energy conservation, and the nature of antimatter.

Lunct
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Antimatter and matter cancel each other out. What does this mean? Do the particles just cease to exist? Does this go against the law of the conservation of energy?
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You would first have to learn what is meant by Antimatter. For instance, it does not consist of Negative Mass (that's a popular misconception).
As usual, Wiki, although not a definitive source, can be a good place to start. You should read that link.
 
Lunct said:
Antimatter and matter cancel each other out.

I wouldn't say that they "cancel each other out". The process is called "annihilation", and always results in the creation of other particles and/or EM radiation.

Lunct said:
Does this go against the law of the conservation of energy?

Nope. Energy and mass are fully conserved through the creation of other particles and radiation which carry away whatever mass and energy the original particles had.
 
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sophiecentaur said:
You would first have to learn what is meant by Antimatter. For instance, it does not consist of Negative Mass (that's a popular misconception).
As usual, Wiki, although not a definitive source, can be a good place to start. You should read that link.
I think I understand, the particles turn into energy, and the amount of energy is in accordance the equation E=mc^2.
That would make sense.
 
Drakkith said:
I wouldn't say that they "cancel each other out". The process is called "annihilation", and always results in the creation of other particles and/or EM radiation
Pop science has to over simplify everything...
 
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Lunct said:
but is it possible for photons to turn back into matter?
Yes.
Google for "pair production" - a sufficiently energetic photon in the vicinity of a heavy nucleus can turn into an electron-positron pair.
(The heavy nucleus is needed because without it there's no way of conserving both energy and momentum).
 
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Nugatory said:
Yes.
Google for "pair production" - a sufficiently energetic photon in the vicinity of a heavy nucleus can turn into an electron-positron pair.
(The heavy nucleus is needed because without it there's no way of conserving both energy and momentum).
but wouldn't the positron and electron want to collide together as they have opposite charges and annihilate?
 
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Lunct said:
but wouldn't the positron and electron want to collide together as they have opposite charges and annihilate?
Not if they have sufficient resulting Kinetic Energy to take them apart ( aka Escape Velocity).
 
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  • #11
Lunct said:
but wouldn't the positron and electron want to collide together as they have opposite charges and annihilate?
They might, and then you get a pair of photons out. That case looks from the outside as if the nucleus absorbed the incoming photon and immediately emitted two less energetic photons. However, if the electron and positron have enough kinetic energy (the incoming photon has substantially more than two electron masses worth of energy, by ##E=mc^2##) then the two particles will fly apart more quickly than the attractive force can pull them together.
 
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  • #12
Nugatory said:
They might, and then you get a pair of photons out. That case looks from the outside as if the nucleus absorbed the incoming photon and immediately emitted two less energetic photons. However, if the electron and positron have enough kinetic energy (the incoming photon has substantially more than two electron masses worth of energy, by ##E=mc^2##) then the two particles will fly apart more quickly than the attractive force can pull them together.
makes sense, you are very good at explaining things.
Thanks
 
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