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How can 'antimatter' be exemplified?

I was reading a book and came across the concept of 'antimatter' sparingly.. it sounds pretty fascinating.

My question is how can it be exemplified in real terms? (Disclaimer: I have absolutely zero physics background unless you count learning the order of the planets during GCSE so I don't really know if the question actually makes any sense.)

But what I mean is, for example, in maths, you can exemplify the concept of 'negative numbers' with 'debt' so can the same be done with 'antimatter'? If so, how? So far, the only thought that has popped into my head is: antimatter exists in parallel universes where everything is equal but opposite so you have antihydrogen rather than hydrogen and etc. That's probably wrong though considering 'parallel universes' is quite an abstract concept. :confused: ..Can anyone enlighten me (in a nutshell, preferably)?

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Reply 1
Preeka
I was reading a book and came across the concept of 'antimatter' sparingly.. it sounds pretty fascinating.

My question is how can it be exemplified in real terms? (Disclaimer: I have absolutely zero physics background unless you count learning the order of the planets during GCSE so I don't really know if the question actually makes any sense.)

But what I mean is, for example, in maths, you can exemplify the concept of 'negative numbers' with 'debt' so can the same be done with 'antimatter'? If so, how? So far, the only thought that has popped into my head is: antimatter exists in parallel universes where everything is equal but opposite so you have antihydrogen rather than hydrogen and etc. That's probably wrong though considering 'parallel universes' is quite an abstract concept. :confused: ..Can anyone enlighten me (in a nutshell, preferably)?

hmmm... Its a bit like looking into a mirror think about the world inside the mirror it might have different laws of physics in theirs than ours ....
think about you as being the matter and the other you inside the mirror as antimatter.
Reply 2
rbnphlp
hmmm... Its a bit like looking into a mirror think about the world inside the mirror it might have different laws of physics in theirs than ours ....
think about you as being the matter and the other you inside the mirror as antimatter.



so it is kind of the whole equal and opposite idea :rolleyes: :cool:

ps; are you suggesting the glass in the mirror is like a portal to another world or is that just a dummied-down way of helping me understand? :p:
Reply 3
The interaction between matter and antimatter is comparable to that between men and women: complete and utter annihilation.
Reply 4
Preeka
so it is kind of the whole equal and opposite idea :rolleyes: :cool:

ps; are you suggesting the glass in the mirror is like a portal to another world or is that just a dummied-down way of helping me understand? :p:

yh kind of...

Ps: I would say the latter :p:
allow it man, i do physics at uni, but please theres no need for this
Reply 6
hairychimpanzee
allow it man, i do physics at uni, but please theres no need for this

:confused:
Basically think of it as anti-matter reacts with other anti-matter in the same way matter does with other matter.
In that respect the are the same.
But when you get anti-matter and matter, they cancel each other out in a big explosion!

It's like how negative numbers work.

3+5=8 and so

-3 + -5 = -8

but -3+3=0

But since energy (of which mass is a form) cannot be created or destroyed, the mass-energy of the matter, and the mass-energy of the anti-matter get turned into light energy (aka explosion). How much light energy?

E=Mc^2 of course!
Reply 9
The_Octopus
Basically think of it as anti-matter reacts with other anti-matter in the same way matter does with other matter.
In that respect the are the same.
But when you get anti-matter and matter, they cancel each other out in a big explosion!

It's like how negative numbers work.

3+5=8 and so

-3 + -5 = -8

but -3+3=0

But since energy (of which mass is a form) cannot be created or destroyed, the mass-energy of the matter, and the mass-energy of the anti-matter get turned into light energy (aka explosion). How much light energy?

E=Mc^2 of course!


Where does this happen? :confused: Or is that only in theory and therefore, hypothetical?
Reply 10
Preeka
Where does this happen? :confused: Or is that only in theory and therefore, hypothetical?

It happened at the beginning of the universe. The big question is why more matter was created than antimatter such that we have matter left over now.
Reply 11
It's just the exact opposite of matter. Anti-protons have charge -1 and positrons (positive electrons) have charge 1. The quarks that make up protons and neutrons are opposite (in matter, an up quark has charge 2/3 and a down quark -1/3, in antimatter the up has charge -2/3 and down 1/3 - remember, a neutron is made from one up quark and two down quarks, and a proton from two up quarks and one down quark). It's really as simple as that.
Reply 12
FXX
It's just the exact opposite of matter. Anti-protons have charge -1 and positrons (positive electrons) have charge 1. The quarks that make up protons and neutrons are opposite (in matter, an up quark has charge 2/3 and a down quark -1/3, in antimatter the up has charge -2/3 and down 1/3 - remember, a neutron is made from one up quark and two down quarks, and a proton from two up quarks and one down quark). It's really as simple as that.

In fact, all quantum numbers are reversed as well, I believe.
Reply 13
wiki entry on antimatter
Uses

Because antimatter can make so much energy, it can be used for a lot of things, such as fuel for going into outer space, or in our cars. The problem is that antimatter is very very expensive to make, and is almost as expensive to store, since it cannot touch regular matter. It takes several hundred million dollars to make less than one-millionth of a gram of antimatter! In fact, it is the most expensive and rare substance on Earth. Since it is so expensive, this means that antimatter is not practical to use as a weapon or as an energy source, because so little of it is available.


As much as wiki is great sometimes, this was clearly written by someone who's watched too much Star Trek and not actually studied any physics.
Reply 14
ashy
As much as wiki is great sometimes, this was clearly written by someone who's watched too much Star Trek and not actually studied any physics.

It was Simple Wikipedia. The real thing is a bit more specialised :P
Reply 15
FXX
It was Simple Wikipedia. The real thing is a bit more specialised :P

Oh, I so didn't spot that >.<

Wtf is simple wikipedia? :s-smilie: Never heard of it!

Well, even then, a lot of it is factually incorrect.
Reply 16
Antimatter is just a name we have given to particles that we have discovered. They are no different essentially to particles that are 'matter', the only difference being that they have an opposite charge, that is equal in magnitude.

For example, a positron is the electron's antimatter 'partner', so it has exactly the same mass, spin, etc. the only difference is that it has a charge of +1e, rather than -1e.

I hope that made sense, I've only just done A level physics, so I'm sure someone who has done a degree will explain better :smile:
ashy
As much as wiki is great sometimes, this was clearly written by someone who's watched too much Star Trek and not actually studied any physics.


It's actually a valid theoritcal concept, the problem with it though is being able to accumulate enough anti-matter to actually make it a viable fuel and also how to store it.

A lot of people here, especially the OP, seem to be under the impression that anti-matter only exists in other universes, or something like that. That's wrong, it does exists in our universe, it always has and it still does. In fact, Matter- Antimatter annihilations occur all the time in our atmosphere.

Preeka
I was reading a book and came across the concept of 'antimatter' sparingly.. it sounds pretty fascinating.

My question is how can it be exemplified in real terms? (Disclaimer: I have absolutely zero physics background unless you count learning the order of the planets during GCSE so I don't really know if the question actually makes any sense.)

But what I mean is, for example, in maths, you can exemplify the concept of 'negative numbers' with 'debt' so can the same be done with 'antimatter'? If so, how? So far, the only thought that has popped into my head is: antimatter exists in parallel universes where everything is equal but opposite so you have antihydrogen rather than hydrogen and etc. That's probably wrong though considering 'parallel universes' is quite an abstract concept. :confused: ..Can anyone enlighten me (in a nutshell, preferably)?


Antimatter really isn't a hard thing to understand, you don't actually need any special understanding of physics or anything. Anti-matter is just the exact opposite of normal matter.

For example if we take an Electron and a Positron (An Anti-Electron), the electron has a near zero mass, a charge of -1 and has a certain "spin" in a certain direction. The Positron will have exactly the same mass as the Electron, opposite charge (+1) and opposite spin (In the opposite direction).

Since the particles are exact opposites, when they meet each other they Annihilate each other in a reaction releasing pure energy as it's only output. (This is the basic principle of using Antimatter-Matter collisions as a viable fuel.)
Reply 18
You Failed
It's actually a valid theoritcal concept, the problem with it though is being able to accumulate enough anti-matter to actually make it a viable fuel and also how to store it.

A lot of people here, especially the OP, seem to be under the impression that anti-matter only exists in other universes, or something like that. That's wrong, it does exists in our universe, it always has and it still does. In fact, Matter- Antimatter annihilations occur all the time in our atmosphere.



Antimatter really isn't a hard thing to understand, you don't actually need any special understanding of physics or anything. Anti-matter is just the exact opposite of normal matter.

For example if we take an Electron and a Positron (An Anti-Electron), the electron has a near zero mass, a charge of -1 and has a certain "spin" in a certain direction. The Positron will have exactly the same mass as the Electron, opposite charge (+1) and opposite spin (In the opposite direction).

Since the particles are exact opposites, when they meet each other they Annihilate each other in a reaction releasing pure energy as it's only output. (This is the basic principle of using Antimatter-Matter collisions as a viable fuel.)

Was the explanation of anti matter aimed at me?

I mean the whole use as a fuel in a car. Even if we accept the Star Trek level of fantasy, that's ridiculous.
ashy
Was the explanation of anti matter aimed at me?

I mean the whole use as a fuel in a car. Even if we accept the Star Trek level of fantasy, that's ridiculous.


No the explanation wasn't aimed at you. That's why I quoted the OP half way through.

In a car..yeah, it's a pretty rediculous idea. However, as a fuel for space travel, the basic idea is fine. The physics works. However like I said, the problems arise when you actually try and store it and also being able to find enough of it. If you can overcome these two problems then it really does become a very viable idea.

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