Antimatter: how they exist in matter?

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    Antimatter Matter
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Discussion Overview

The discussion revolves around the nature and existence of antimatter in relation to matter, exploring questions about their annihilation, production, and the balance of matter and antimatter in the universe. Participants delve into theoretical and conceptual aspects, as well as implications from particle physics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants propose that antimatter and matter annihilate upon contact, raising questions about how antimatter can exist in matter without annihilating.
  • Others argue that matter can exist independently of antimatter, challenging the notion that they must coexist.
  • A participant clarifies that antimatter is composed of antiparticles, such as positrons, and provides examples like antihydrogen.
  • There is mention of pair production as a method of creating antimatter from energy, specifically through interactions involving gamma photons.
  • Some participants discuss the implications of CP-violation as a potential explanation for the predominance of matter over antimatter in the universe.
  • Antimatter is noted to exist in natural processes, such as beta decay, where anti-neutrinos are emitted.
  • One participant highlights that anti-neutrinos do not annihilate with neutrinos due to the energy constraints involved in their interactions.
  • There is a discussion about the theoretical framework of antimatter, including Dirac's equation and the concept of a "sea" of antiparticles.

Areas of Agreement / Disagreement

Participants express differing views on the coexistence of matter and antimatter, with some asserting that they cannot exist together without annihilation, while others maintain that matter can exist independently. The discussion remains unresolved regarding the fundamental nature of their relationship and the implications for the universe.

Contextual Notes

Participants reference various theoretical concepts and experimental observations, but there are limitations in the clarity of definitions and assumptions about the nature of antimatter and its interactions with matter.

Deadevil
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I was wondering about antimatter. Antimatter & matter anihilate when they combine. But how they exist in matter? Why matter anihilate due to the presence of antimatter & matter? Also scientist are thinking about antimatter that where it had gone after big bang but i think that this antimatter exist in matter in our surroundings. Matter do not exist without antimatter! Am i right in this regard?
 
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Deadevil said:
I was wondering about antimatter. Antimatter & matter anihilate when they combine.

Correct.

But how they exist in matter?

I don't understand what you're asking, please clarify.

Why matter anihilate due to the presence of antimatter & matter?

Simple. That's what we've observed.

Also scientist are thinking about antimatter that where it had gone after big bang but i think that this antimatter exist in matter in our surroundings.

They're wondering why there was more matter than antimatter at the beginning of the Universe, not where it went. And how could antimatter exist in matter in our surroundings? Also, wouldn't it annihilate?

Matter do not exist without antimatter! Am i right in this regard?

Why would matter not be able to exist without antimatter?
 


Matter do not exist without antimatter!

It's not some kind of the darkness cannot exist without light kind of thing (although iirc it was once thought of in this way), right now we know that there is more matter than antimatter.

I'm really not too sure what you mean about 'But how they exist in matter?' or the rest of your question really... :confused:
 


Just to take a step back to square one, are you sure you know what antimatter is? Particles have antiparticles with opposite charges e.g. the negatively charged electron's antiparticle is the positively charged positron. Antimatter is simply matter made out of antiparticles e.g. antihydrogen is composed of positrons orbiting the nucleus (instead of electrons) within which are neutrons and antiprotons.
 
Deadevil said:
Antimatter & matter anihilate when they combine.
A particle can annihilate with its corresponding antiparticle.
- there are bound states with an electron and a positron (the antiparticle of the electron). They are unstable and the two particles annihilate after a while, but not necessarily instantly.
A positron will not annihilate with a proton, for example, as they are different particles.

But how they exist in matter?
No permanent antimatter exists within matter. It is possible to store antimatter in accelerator structures, but you have to avoid contact with matter to do so.
Antiparticles can exist as virtual particles, but they have a very short lifetime and annihilate quickly.

Why matter anihilate due to the presence of antimatter & matter?
It is a result of the theory, and experiments confirm it. There is no real "reason" why things are like this.

Matter do not exist without antimatter!
Matter can exist without antimatter.
 
Ok.thnx for rplying everyone! But let me make my question clear.first of all, how antimatter is produced. Is it produce from matter? If yes! Then how both antimatter & matter exist together since antimatter is extracted from ma tter. Why they do not anihilate when they are together in the form of matter.if it exist in matter then to balance matter every matter-antimatter pair should have to exist in atom .i.e. electron & positron. Which makes the matter & antimatter in equal quatities in universe. Now explain this!
 
Antimatter can be made in many different ways.

For example, look up "pair production". You'll notice that the electron-positron pair is created out of a gamma photon.

Your other question on the matter-antimatter amount in the universe is a bit more complicated, and it is still an active research area. The popular candidate to explain why our universe is predominantly made of matter and not antimatter is our observation of what is known as CP-violation in certain elementary particle decay. I don't know to what extent or to what level of details you are capable of understanding, so I'll stop here. But you can always do a search on "CP-violation" to find further explanations.

Zz.
 
Antimatter also exists in nature. In radioactive beta minus decay, an anti-neutrino is also emitted, which is the anitparticle of the electron neutrino. (BTW, the neutrino and anti-neutrino are both weakly interacting, so the probability of them interacting is relatively small, isn't it?)
 
The other "problem" that anti-neutrinos have is that they can't just annihilate with ordinary neutrinos. This is because the only particle that could be produced by such an annihilation - the Z0 boson - is heavy, almost invariably much heavier than the COM energy of the neutrino/anti-neutrino pair. This is in stark contrast with "ordinary" [baryonic and charged leptonic] matter and antimatter, which have electric charges and can therefore annihiliate easily into massless photons.

A virtual Z0 could, once in about 4 x 10x blue moons, extremely fleetingly pop into existence from a neutrino/anti-neutrino collision, but the only decay channel then open to it (unless the available energy were at least 2me) would be ... to decay back into a neutrino and anti-neutrino.

As a result, many anti-neutrinos, including those from the cosmic neutrino background, exist and pass through us regularly every day, and we don't even notice them!
 
  • #10
matter and antimatter do not coexist,so during a possesses you break something up . I mean, it's not like everything consists of antiparticles and particles.
You can have just 2 particles, collide them, and BANG several things to appear... antimatter is made to conserve certain quantities that are needed to be conserved. How are they made? Because energy and matter are one and the same, so particles and antiparticles can be made out of energy (or fields if you want to speak in modern terms).

Dirac's equation proposed antimatter.
At first it was a laughable theory, because it proposed negative energies.
After some hard time Dirac gave the explanation-model of the sea of antiparticles, which of course is not a real "sea" but it is a model explaining his theory.
Antimmater was discovered.
Thanks to Feynman's diagrams we can see better the possesses during such interactions.
 

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