Matter and Antimatter

  • #1

Main Question or Discussion Point

If matter and antimatter are placed next to each other, will they attract each other and annihilate ? Do we have strong evidence regarding the existence of anti-matter ?
 

Answers and Replies

  • #2
.Scott
Homework Helper
2,534
912
Antimatter has been created in labs. It may be the most expensive material man possesses.

https://en.wikipedia.org/wiki/Antimatter#Natural_production

If an anti-matter particle has a charge, it will attract is matter counterpart - because opposite charges attract. Otherwise, there will be gravitation attraction - but that is often very slight.

On Earth, antimatter needs to be kept in magnetic bottles in a vacuum - otherwise it will contact air or the floor of the container.
 
  • Like
Likes ohwilleke and Adhruth Ganesh
  • #3
DrClaude
Mentor
7,339
3,520
If matter and antimatter are placed next to each other, will they attract each other and annihilate ?
It depends. If you place an electron and a positron next to each other, they have opposite charges so they will attract, and eventually they will annihilate each other. Look up positronium.

If you put a positron next to an anti-proton EDIT: proton, they will repel since they have a like charge, and they will never by able to annihilate each other.

Do we have strong evidence regarding the existence of anti-matter ?
Yes. For instance, anti-matter is created all the time is hospitals: https://en.wikipedia.org/wiki/Positron_emission_tomography
 
Last edited:
  • Like
Likes ohwilleke and Adhruth Ganesh
  • #4
Antimatter has been created in labs. It may be the most expensive material man possesses.

https://en.wikipedia.org/wiki/Antimatter#Natural_production

If an anti-matter particle has a charge, it will attract is matter counterpart - because opposite charges attract. Otherwise, there will be gravitation attraction - but that is often very slight.

On Earth, antimatter needs to be kept in magnetic bottles in a vacuum - otherwise it will contact air or the floor of the container.
Fine. Thank you for your answer !
 
  • Like
Likes berkeman
  • #5
It depends. If you place an electron and a positron next to each other, they have opposite charges so they will attract, and eventually they will annihilate each other. Look up positronium.

If you put a positron next to an anti-proton, they will repel since they have a like charge, and they will never by able to annihilate each other.


Yes. For instance, anti-matter is created all the time is hospitals: https://en.wikipedia.org/wiki/Positron_emission_tomography
Thank you so much !
 
  • Like
Likes berkeman
  • #6
Drakkith
Staff Emeritus
Science Advisor
20,861
4,606
Not only is antimatter created and used every single day in many different places around the world, modern particle physics is constructed using a theory that contains antimatter. We crash particles together in colliders and watch what comes out of the collisions, and these events always closely obey our predictions using this theory. If antimatter didn't exist, then our theory is suspiciously accurate for being so wrong. Not only that, but we'd have to come up with an explanation for the particle tracks we see in cloud chambers and other related detectors that don't match any of our 'regular' matter particles. If they aren't antimatter particles, then why are they acting exactly as if they have opposite charge and other properties compared to normal matter particles?

Antimatter is the simplest explanation to all of these issues, and it follows directly from both theory and experience in the early 20th century when we had to explain other effects by proposing the existence of new types of particles. Antimatter is the simplest, least complex explanation that still accurately explains an enormous number of observations and experiments. You will not find another explanation that does so well.
 
  • Like
Likes ohwilleke and Adhruth Ganesh
  • #7
Not only is antimatter created and used every single day in many different places around the world, modern particle physics is constructed using a theory that contains antimatter. We crash particles together in colliders and watch what comes out of the collisions, and these events always closely obey our predictions using this theory. If antimatter didn't exist, then our theory is suspiciously accurate for being so wrong. Not only that, but we'd have to come up with an explanation for the particle tracks we see in cloud chambers and other related detectors that don't match any of our 'regular' matter particles. If they aren't antimatter particles, then why are they acting exactly as if they have opposite charge and other properties compared to normal matter particles?

Antimatter is the simplest explanation to all of these issues, and it follows directly from both theory and experience in the early 20th century when we had to explain other effects by proposing the existence of new types of particles. Antimatter is the simplest, least complex explanation that still accurately explains an enormous number of observations and experiments. You will not find another explanation that does so well.
Thanks a lot !!
 

Related Threads on Matter and Antimatter

  • Last Post
Replies
10
Views
2K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
17
Views
5K
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
9
Views
2K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
7
Views
3K
  • Last Post
Replies
8
Views
2K
  • Last Post
Replies
3
Views
2K
Top