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How can 'antimatter' be exemplified? watch

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    Quantum numbers, their opposites=antipartcile, and they react only with its particle, some particales do not have an antiparticle such as the photon. Antimatter has been created on earth artificially in very very small amounts
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    (Original post by You Failed)
    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.
    Ok just checking :tongue:

    And yeah I suppose, in theory. There's also the problem of turning the annihilation into a useful source of energy - it would need to be exceptionally well controlled and moderated. What kind of power generation system could feasibly use matter/anti-matter annihilations? I have the idea of a combustion engine in my head - the simple concept of taking a little bit of what's in storage to drive something. Considering the whole system would have to be controlled with electric and magnetic fields, it would be an engineering nightmare.

    Consider the Zeeman and Stark Effects; a collection of even electrons can split into various directions in the presence of a uniform electric or magnetic field depending on their quantum numbers. Unless you want to design a way of accommodating that in your engine design, you'd need a way to ensure you have only m_l = 1 electrons in your store, for example.

    Even a simple engine would make CERN look like child's play. The other issue is that creating antimatter requires enormous amounts of energy itself. Not really a good idea when energy is a depleting commodity :tongue:
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    (Original post by 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.)
    I do more or less understand the basic idea behind it and did from before - just didn't know if what i was asking was a 'feasible' question being a layman, so to speak. (like if someone asked about the 27th letter of the alphabet. u'd know they don't really know what they're talking about :p:).

    I just wanted to be able to link the concept of antimatter like you can go from 'negative numbers' to 'debt' so that 'antimatter' wasn't just a floating idea in my head but I'm beginning to think its more of just a theory-type thing, really.
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    (Original post by 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)?
    just watch star trek and all will be fine.... not....
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    (Original post by Preeka)
    I do more or less understand the basic idea behind it and did from before - just didn't know if what i was asking was a 'feasible' question being a layman, so to speak. (like if someone asked about the 27th letter of the alphabet. u'd know they don't really know what they're talking about :p:).

    I just wanted to be able to link the concept of antimatter like you can go from 'negative numbers' to 'debt' so that 'antimatter' wasn't just a floating idea in my head but I'm beginning to think its more of just a theory-type thing, really.
    You don't understand.

    Antimatter exists in practice in the universe right now. Each matter particle (electrons, protons, neutrinos, muons, blah blah blah) have antiparticle partners. So:

    Matter/Antimatter

    Electron/Positron
    Proton/Anti-proton
    Neutrino/Anti-neutrino

    The antiparticle has opposite quantum numbers like spin, EM charge, colour charge etc (this may be above you, don't worry). It's not the same as negative numbers at all - the analogy stops at annihilation. They are real particles which just happen to be the quantum opposites of the particles you already know about, and there's nothing particularly remarkable about them. They're just as real as matter particles.
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    (Original post by Preeka)
    I do more or less understand the basic idea behind it and did from before - just didn't know if what i was asking was a 'feasible' question being a layman, so to speak. (like if someone asked about the 27th letter of the alphabet. u'd know they don't really know what they're talking about :p:).

    I just wanted to be able to link the concept of antimatter like you can go from 'negative numbers' to 'debt' so that 'antimatter' wasn't just a floating idea in my head but I'm beginning to think its more of just a theory-type thing, really.
    Anti-matter is not a theortical thing. It is a physical particle that exists, even in our own atmosphere.

    Surely by trying to come up with analogies you're just making it more complicated, considering the original topic is not complicated at all.

    While the name suggests it's something quite complex and exotic, it's really not. They're just particles with opposite charge and spin compared to their "non-anti" counterparts.
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    Perhaps the best way to describe how antimatter works is that you think about time reversal.
    If you look at the most well known physics equation.
    E = mc^2
    This is actually a single solution to a lesser known equation.
    E^2=m^2c^4 + p^2c^2

    Assuming p = 0? What is the solution to this equation?
    Spoiler:
    Show
    E= $\pm$mc^2


    Spoiler:
    Show

    So, most people disregard the negative solution. However this is obviously going to be a bad idea since I am discusing it.
    The other way to think about this is to substitute the solution into equations with E in it.
    When using this in the Quantum Mechanics, we have...
    \psi(t)= e^{-i E t} \psi(0)
    \psi(t)= e^{i mc^2 t} \psi(0)
    vs
    \psi(t)= e^{-i mc^2 t} \psi(0)

    The former being the negative solution, whilst the positive solution is the second formula. This can be read as one particle transforms with time as though it were going backwards in time.
    This could be thought as being a particle that would go backwards in time. It would react as though it would move in an electric field in the wrong way (only the right way when you reverse time).
    Also you can think of an electron positron event as being the point where an electron goes from going forward in time to going backwards.
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    Using Antimatter as fuel seems like quite a poor idea.
    To contain antimatter is damned hard. Remember it can NEVER be touched.
    This means that it would require some pretty heavy equipment to do so. Only a handful of technologies exists to do this and none of them can contain more than a few thousand protons at best. This of course means that there is very little energy density that is possible.

    Finally the production of antimatter is not exactly easy, that is to say a HUGE amount of energy is required to make a very small amount of antimatter's worth of energy.
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    (Original post by Preeka)
    I do more or less understand the basic idea behind it and did from before - just didn't know if what i was asking was a 'feasible' question being a layman, so to speak. (like if someone asked about the 27th letter of the alphabet. u'd know they don't really know what they're talking about :p:).

    I just wanted to be able to link the concept of antimatter like you can go from 'negative numbers' to 'debt' so that 'antimatter' wasn't just a floating idea in my head but I'm beginning to think its more of just a theory-type thing, really.
    No.
    There is antimatter in the universe : fact
    Anti-hydrogen has been produced in CERN but it cannot be stored.
    Anti-protons and positrons can be stored in small quantities.
    If you want to know more read: "antimatter" by Frank Close it's a good book and it's very well explained
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    (Original post by Mehh)
    Perhaps the best way to describe how antimatter works is that you think about time reversal.
    If you look at the most well known physics equation.
    E = mc^2
    This is actually a single solution to a lesser known equation.
    E^2=m^2c^4 + p^2c^2

    Assuming p = 0? What is the solution to this equation?
    Spoiler:
    Show
    E= $\pm$mc^2


    Spoiler:
    Show

    So, most people disregard the negative solution. However this is obviously going to be a bad idea since I am discusing it.
    The other way to think about this is to substitute the solution into equations with E in it.
    When using this in the Quantum Mechanics, we have...
    \psi(t)= e^{-i E t} \psi(0)
    \psi(t)= e^{i mc^2 t} \psi(0)
    vs
    \psi(t)= e^{-i mc^2 t} \psi(0)

    The former being the negative solution, whilst the positive solution is the second formula. This can be read as one particle transforms with time as though it were going backwards in time.
    This could be thought as being a particle that would go backwards in time. It would react as though it would move in an electric field in the wrong way (only the right way when you reverse time).
    Also you can think of an electron positron event as being the point where an electron goes from going forward in time to going backwards.
    You do realise the OP said they had zero physics background whatsoever?

    I have finished A Level Physics and will be studing it at Uni and I still cannot understand the point you are making, whether or not that means I am bad at Physics or whatever it certainly means the OP will have little hope of following it.
 
 
 

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