# Tag Info

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Yes, the article you linked and quoted is describing a proposed explanation for observed diffuse gamma ray emissions from the center of our galaxy. The proposed mechanism is that of dark matter/anti-dark matter annihilation in the alleged dark-matter halo in our galaxy. However, you seem to have gotten a wire crossed - this has nothing to do with Gamma Ray ...

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As you point out, to create the antimatter, we would need a fusion reactor, or something equivalent (solar power, etc) in the first place. That means it will not be useful as a primary power source. However, with antimatter we can store a tremendous amount of energy in a very small package - if we ignore the issues of storing it without contacting its ...

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How is relativity related to anti-particles? As far as I know relativity doesn't say anything about antiparticles. But particle physics does. Have a look at the Einstein-de Haas effect which "demonstrates that spin angular momentum is indeed of the same nature as the angular momentum of rotating bodies as conceived in classical mechanics". An electron ...

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I would like to hear a deeper explanation of what we believe anti-matter to be, why it annihilates with matter and how this relates to relativity. This is the table of elementary particles deduced from innumerable measurements: Each particle has a characteristic mass and several characteristic quantum numbers. To each particle there corresponds an ...

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Do matter and antimatter annihilate or release energy? They typically annihilate and release energy. Check out electron-positron annihilation, and low-energy proton-antiproton annihilation. Image credit CSIRO, see The Big Bang & the Standard Model of the Universe Do matter and antimatter eliminate each other or release their equivalent ...

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The statement that a positron is like an electron moving backwards in time is in itself perfectly explainable with classical physics. As the charge of the particles is opposite, the force caused by the electrical and the magnetic field i.e. q(E + v x B) will be opposite. So, fields accelerating electrons, will decelerate positrons at the same rate and vice ...

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Have a look at this Big Bang graph: Annihilation means that when a particle hits an antiparticle, there exists a probability that they would both disappear and the energy turned into other particle antiparticles. It is the quantum numbers that cancel each other. At the elementary particle stage of the Big Bang, the energy is carried by elementary particles ...

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Your intuition is quite reasonable. We observe (based on cosmic rays) that the universe is basically all matter, no antimatter. At the high energy state of the big bang we would expect an even balance. Cosmological theories need to explain the asymmetry in baryons vs antibaryons

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Rather than using a magnetic field, you are better off using a strong electric field to separate them - since the initial direction of the electron / positron is somewhat random, a magnetic field will deflect but not separate in a meaningful way. An electric field can pull the positrons one way, and the electrons the other way - regardless of their initial ...

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Black holes contain so much energy in so small a space that indeed many particles of tremendous variety can be created and destroyed as long as certain conservation laws aren't being violated. Although I did crack a smile at the physician comments people made, I would like to let you know that a physicist works with physics and a physician works with ...

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Black holes are extremely heavy, black bodies, all of which have a singularity in the centre. They are not anti-matter, they are a sort of 'deep well' of space-time, however, their strong gravitational force attracts matter into themselves. When matter and anti-matter annihilate each other, energy is conserved in the form of photons. Ps: A physician has ...

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$C$ stands for charge. Charge symmetry implies that if the charge of all particles were to be inverted - particles become anti-particles and viceversa - the universe would look exactly the same. A universe made of matter would be indistinguishable from one made of antimatter. So if a given process allows for two matter particles (say, a proton and a ...

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Antimatter is matter going backwards through time. No it isn't. Whilst that idea might appear to have some pedigree, (see retrocausality on Wikipedia), it's bunk I'm afraid. Antimatter is like matter, but it has the opposite chirality. Google on positron chirality. Whilst one can mathematically model the positron as a "time reversed electron", it isn't ...

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Antimatter increase in entropy over time. We can verify this with a thought experiment. Take ten positrons. Put five in one side of a chamber with a barrier and then the other 5 on the other side of the barrier in the same chamber. The chamber and barrier are also made of antimatter. The positrons repel each other and so each have a certain amount of kinetic ...

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We know that antimatter has positive energy, because in particle experiments (see pair production) the created antiparticles carry positive energy away from the interaction. Also in annihilation the particle and antiparticle energy both convert positively into the outgoing products. Positive energy gets to the stress-energy tensor of General Relativity as ...

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Assuming the observed asymmetry in matter and antimater in the universe the antimatter to be detected must come from the interactions of matter particles with excess energy, creating a particle antiparticle pair. The lightest pairs are a pair of neutrino antineutrino. To be created, the weak interaction vertex has to be involved which is much smaller than ...

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Surprisingly little which is currently established would change: our current model of particle physics, the Standard Model, does not deal with gravity; our current model of gravity, General Relativity, does not deal with quantum things. A bunch of things which are not currently established could change dramatically, but we can expect that these will be ...

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What is the most common form of antimatter in the universe? The proton. Yes, the proton. See this article about positronium which says "to a first approximation it can be regarded as a sort of light hydrogen atom". Positronium is a short-lived exotic atom, comprised of an electron and a positron. We call the electron matter, and we call the positron ...

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The notion of anti-particle emerges as soon as special relativity is taken into account. For a relativistic particle of mass $m$, its energy and momentum satisfy $E^2 = p^2 + m^2$. To illustrate where the anti-particles are coming from, let's take the simplest "wave function equation" (that's an abuse of language since it's an equation for fields), i.e. the ...

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