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You seem to think that matter is exemplified by atoms, elements and even molecules. This is incorrect. Particles are matter, and antiparticles are antimatter. An example of this, are electron and anti-electron, proton and anti-proton. Next, you need to understand that a particle and its antiparticle are oppositely charged, therefore, they "naturally" ...

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Your matter as well as your antimatter can be described by a propagating wave packet (for example a Gaussian). The overlap of both wave functions gives you a Luminosity $\mathcal{L}$. Now rate of annhilation events is the cross section for this annhilation process times the Luminosity $$R=\mathcal{L} \sigma$$ So the amount of overlap of both wave ...

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Positrons and antiprotons are contained and manipulated with electromagnetic fields, as they annihilate when close to matter atoms and molecules. The only neutral atomic antimatter at the moment is the creation of antiHydrogen in labs. Have a look at the ALPHA experiment at CERN. Acoustic manipulation presupposes bulk matter, the kind that goes with 10^23 ...

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Acoustic levitation requires a material medium to transmit the sound waves that suspend the object you want suspended. The object must contact the medium in order to be suspended. If the object is made of antimatter, it will instantly annihilate upon contact with the material medium that transmits the acoustic waves. You can't transmit acoustic waves in ...

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Annihilation is a quantum process and as such it is probabilistic. You are correct that particles do not touch in a classical sense, but each interaction has a cross section. Particle and antiparticle are attracted to each other because of opposite charge and when they get sufficiently close, they interact. In case of electrically charged particles (like ...

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Why, yes, they do! Probably the most decisive way to show this involves "handedness" of neutrinos. I won't get too much into the details here, but neutrinos are nearly massless and travel at nearly the speed of light; and when something travels at the speed of light you can describe its spin as either "right-handed" (momentum and spin are in-line) or ...

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We all learned in school that gravity is associated with mass. For example if we have two bodies with masses $m$ and $M$ then Newton's law tells us that the gravitational force between them is: $$F = \frac{GmM}{d^2}$$ So if either object has zero mass the force goes to zero. And since photons are massless it's entirely reasonable to ask if the gravity ...

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Similarly the reverse is possible where a photon can spontaneously morph into two equal particles of matter and antimatter. Wrong, a photon has to interact with some other particle or field in order, if it has enough energy , to create a particle antiparticle pair. This is because of special relativity: the photon has a mass zero whereas the particle ...

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