The antimatter tag has no wiki summary.
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Anti-particle problem for Dirac sea
According to the Dirac hole theory we know that Dirac sea is completely filled with negative energy, called vacuum. We will need $2mc^2$ or greater to get electron and a positron by incident photon.
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Would an antimatter beam create multiple matter-antimatter explosions?
To expand upon the question - in an atmosphere, would a beam of pure antimatter (disregarding technical difficulties creating such a beam or passing it through a medium) interact with the matter in ...
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What if the antimatter in the center of our galaxy could annihilate and cause a chain reaction?
Being said that the antimatter - matter reaction is faster than that of a fission and fusion, what if the antimatter cloud found at the center of our galaxy could really able to react with matter from ...
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Anti-Matter Black Holes
Assuming for a second that there were a pocket of anti matter somewhere sufficiently large to form all the type of object we can see forming from normal matter - then one of these objects would be a ...
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Andromeda is made of antimatter. Am I wrong? Why?
Andromeda is made of antimatter. Am I wrong? Why?
Of course I do not know that Andromeda is made of antimatter.
_but____ I do not know that Andromeda is made of matter.
Does anybody know what is ...
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Do particles and anti-particles attract each other?
Do particles and anti-particles attract each other?
From the very basic understanding that they are created out of nothing mutually and collide to annihilate each other seems to indicate this happens ...
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Could the outer structure of the Universe be made from Antimatter?
Cern recently stated that antimatter may be repelled by matter, much like the opposite effect of Gravity. So is it possible that antimatter is actually repelled to the edges of the Universe to create ...
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supressing certain decay paths and enhancing others with interference
In a scattering reaction, there are many possible final states for the products, each with different production rates.
Question: Is there a way in which we could in general supress certain rates ...
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Is anti-matter matter going backwards in time?
Or: can it be proved that anti-matter definitely is nót matter going backwards in time?
From wikipedia:
[There is considerable speculation as to why the observable universe is apparently almost ...
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Anti-matter black hole and time
I have recently read some hard science-fiction story based on an assumption that if time stops (from external observer's perspective) on the event horizon of black hole, then in an anti-matter black ...
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No hair theorem for black holes and the baryon number
The no hair theorem says that a black hole can be characterized by a small number of parameters that are visible from distance - mass, angular momentum and electric charge.
For me it is puzzling why ...
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What actually happens when an anti-matter projectile collides with matter?
I'm trying to understand what would really happen when large quantities (e.g., 10g) of anti-matter collide with matter. The normal response is that they'd annihilate each other and generate an ...
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If an anti-matter singularity and a normal matter singularity, of equal masses, collided would we (outside the event horizon) see an explosion?
If an anti-matter singularity and a normal matter singularity, of equal masses, collided would we (outside the event horizon) see an explosion?
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Strings and QFT: particles moving backward in time?
New question: In string theory and QFT, do particles travel back in time? Not related to antimatter: Do they travel back and forth in time in reality or are these just interpretations of mathematical ...
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Antimatter in the universe [duplicate]
Is it possible that some parts of the universe contain antimatter whose atoms have nuclei made of antiprotons and antineutrons, sorrounded by antiprotons? If yes what can be the ways to detect this ...
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How fast is the matter and antimatter reaction compared to nuclear chain reaction?
What I mean is, the nuclear chain reactions take microseconds for every generation and that is the reason that nuclear weapons exist. Because in nuclear reactors the reaction rate is much slower thus ...
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How to guarantee that a kilogram of antimatter will quickly annihilate another kilogram of matter?
What I mean is, suppose we could somehow get a kilogram of matter and contain it safely. Now lets say we want to make a bomb using this kilogram, now, we have two ways, either store another kilogram ...
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How much energy is carried away by neutrinos in matter-antimatter annihilation?
Some people say that neutrinos carry away most of the energy, some others say just a fraction. So what is the truth ? what is the percentage of energy lost due to neutrinos ?
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Gravitational potential energy with regards to annihilation
Given particles A, B, C and D, where:
A and B have an equivalent mass
C and D have an equivalent mass, both larger than A (or B)
D is the antiparticle of C.
A and B start close to C, but with ...
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Effect of mass matter-antimatter annihilation? [duplicate]
Possible Duplicate:
What actually happens when an anti-matter projectile collides with matter?
If a large amount of antimatter is suddenly released or launched in the open and expands, ...
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Could much of the “missing” antimatter make up neutrons?
A neutron can decay into a proton, an electron, and neutrino. Could an antiproton, a positron, and a neutrino combine into a neutron? Could this be where much of the "missing" antimatter is?
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Do particle pairs avoid each other? Please end my musings
Can you explain what happens when a particle and its antiparticle are created. Do they whiz away from each other at the speed of light or what? I suppose that they don't because otherwise they would ...
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When is the FAIR accelerator supposed to be finished? [closed]
The FAIR accelerator is a planned facility for antiproton and ion research.
Ground water wells are being put in, the forest is being cleared... But when is it supposed to be completed? Does anyone ...
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Electric charge in string theory
The mass of an elementary particle in string theory is related with the way the string vibrates. The more frantically a string vibrates the more energy it posses and hence the more massive it is. My ...
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Spontaneous pair production?
So I've been looking into particle-antiparticle pair production from a gamma ray and don't understand one thing.
Let's say I have a 1,1 MeV photon and it hits a nucleus - electron-positron pair with ...
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how do we know that the base of entire universe is the proton (hydrogen) and not the antiproton?
It may be that the base of a part of the world is anti-proton, We've always been on the planet Earth and the Milky Way.
how do we know that the base of entire universe is proton (hydrogen atom)?
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How would we tell antimatter galaxies apart?
Given that antimatter galaxies are theoretically possible,
how would they be distinguishable from regular matter galaxies?
That is, antimatter is equal in atomic weight and all properties, except for ...
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matter anti-matter world
let us suppose the gedanken experiment
a man isolated into a room he ask if he is made of matter oder of antimatter
could he set some experiments to see if he is made of matter or if he is made of ...
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4answers
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What is pure energy in matter antimatter annihilation?
I used to read the term "pure energy" in the context of matter antimatter annihilation,
are them photons? is it other form of heat, are particles with mass ?
What does it refer to?
thanks
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Schrödinger's equation, time reversal, negative energy and antimatter
You know how there are no antiparticles for the Schrödinger equation, I've been pushing around the equation and have found a solution that seems to indicate there are - I've probably missed something ...
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Complete annihilation of matter-antimatter [duplicate]
Possible Duplicate:
More on matter and anti-matter
Everyone knows that when matter and anti-matter come in contact, they result in pure energy.
I want to know that if atoms and anti-atoms ...
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2answers
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Creation of particle anti-particle pairs
I was reading some QFT notes and there is one point that I don't understand, they are justifying why we need QFT saying that the number of particles is not preserved once we consider special ...
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Why Negative Energy States are Bad
The argument is often given that the early attempts of constructing a relativistic theory of quantum mechanics must not have gotten everything right because they led to the necessity of negative ...
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Why do or don't neutrinos have antiparticles?
This was inspired by this question. According to Wikipedia, a Majorana neutrino must be its own antiparticle, while a Dirac neutrino cannot be its own antiparticle. Why is this true?
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Can a neutron be created from pure energy
Is it possible to create a neutron out of pure energy, i.e. not by bringing a bunch of already-existing quarks together? (A quick calculation using E = mc2 shows the energy required would be about 1.5 ...
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On non-local physics
Recently I've encountered work by prof. B.V Alekseev, in which he claims that some physical problems can be easily solved if we consider non-local interactions in kinetic theory (interactions of ...
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Exotic Matter — What is it?
I have a conceptual understanding of some theoretical physics concepts, so without getting into the math, what is exotic matter?
I have read some articles that say it is anything not normal, while ...
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Would a positron energy weapon cause the same effects as Zat Gun from SG-1 from assuming normal Physics?
question stems from the following answer on SciFi StackExchange: http://scifi.stackexchange.com/questions/6404/in-stargate-is-there-an-in-universe-explanation-of-the-cumulative-effect-of-zat/6405#6405 ...
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What is anti-matter?
Matter-- I guess I know what it is ;) somehow, at least intuitively. So, I can feel it in terms of the weight when picking something up. It may be explained by gravity which is itself is defined by ...
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positronium BEC stability
After reading this article regarding Positronium BEC formation (for lasing purposes), there is a mention in there regarding Ps "up" atoms not annihilating with "down" atoms, the article is pretty ...
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scaling laws for density and temperature of high-energy explosions
I'm wondering if there are heuristic ways to derive how the peak density and temperature of nuclear explosions scale with the amount of fissile/fusible material.
Does it matter what the explosion ...
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Why do electron-positron pair annihilate upon contact?
I'll a appreciate a layman's explanation, if there exists one, to this question that arose when reading an popular-science level article on Einstein and the $E=MC^2$ equation.
What I mean is that, ...
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Antimatter bomb
I stumbled upon this wikipedia article on antimatter weaponry.
Being greatly appalled by the sad fact that large sums of money are being wasted on this, I could not stop myself from thinking for a ...
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How many anti-particles hit the ground?
I am curious to know the amount of flux of anti-particles that arrive to the ground in the cosmic rays. The reason is that I thought it should be very improbable that an anti-particle traveling ...
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Anti particles: What exactly is inverted?
http://en.wikipedia.org/wiki/Antiparticle says "Corresponding to most kinds of particles, there is an associated antiparticle with the same mass and opposite electric charge."
and
What is anti-matter?
...
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What makes *electric* charge special (wrt. CPT theorem)?
I'm wondering why the 'C' in CPT - charge conjugation - refers specifically to electric charge. Of course you could say that C is just defined as $e^+ \leftrightarrow e^-$... but there has to be ...
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Bigger anti-matter particles
I have learned about the existence of positrons as a decay product from uranium fission - if I'm not mistaken. Is there any evidence for higher 'mass' anti-matter, or is that mere speculation or ...
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Can cosmic inflation be explained by matter antimatter reactions?
The big bang theory proposes that equal amounts of matter and antimatter were created in the beginning. Shortly afterwards most of it annihilated. Could that have produced enough energy to drive ...
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How does Annihilation work?
I'm wondering why matter and antimatter actually annihilates if they come into contact. What exactly happens? Is that a known process? Is it just because of their different charges? Then what about ...
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What would happen after the collision matter and the anti-matter [duplicate]
Possible Duplicate:
What actually happens when an anti-matter projectile collides with matter?
Suppose 1 kg of a stray meteorite anti-matter moves to the earth.
What would happen after ...
