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At the Large Hadron Collider we have studied matter down to a length scale of about $10^{-19}$ metres, which is about a billion times smaller than an atom. All the results so far confirm our existing theories. So it seems very unlikely that an undiscovered class of small atoms exists. The size of an atom depends on well understood physical principles. At ...

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Yes. For the phrasing of this question, the neutron qualifies. Neutrons have been slowed and collected, which are diverted from nuclear reactors via beamports. The methods for doing this are quite complicated, but in the final state, they are confined within a box where the "walls" present a nuclear barrier to the neutrons. The neutrons have a wavelength ...

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The fact of the matter is that there are no stable mesons, that might conceivably form states bound by the strong force, as the nucleus is bound. Within the nucleus there exist virtual mesons, i.e. described as pions etc but not on mass shell To a large extent, the nuclear force can be understood in terms of the exchange of virtual light mesons, such as ...

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As anna mentioned, there are non quark models which clarify exotic hadrons. In principle, they are allowed in Quantum Chromodynamics (QCD). Non-quark models predict 1.hybrid mesons: Include quark anti-quark pair and gluon. 2.Glueballs: Gluons are their own bound states. 3.Exotic hadrons as in figure below which exchange pion at low energies (couple ...

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Electron can't teleport from one energy level to another. Rather, when you shine light of the frequency, corresponding to the given transition between levels, on the atom in initial energy state, the probability of finding this atom in the other energy state increases with time. This probability can be computed via Fermi's golden rule. The idea of ...

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The energy shifts of transitions including the s-orbitals of various isotopes of hydrogen are dependent on the proton's charge radius and are a surprisingly sensitive tool for this kind of thing. Recently this has been checked with muonic hydrogen, with surprising results. Paper at http://dx.doi.org/10.1126/science.1230016, and references therein. Related ...

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The quote is correct but a bit misleading. The statement "In doing so it also liberates particles known as neutrinos" includes electrons also which are the other particle that is released in neutron decay, and is the way that beta decays were discovered. The neutrino was discovered because neutron decay showed a three body momentum spectrum for the ...

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Maybe you should look up the definition of what an orbital is again. Your question doesn't make much sense. https://en.wikipedia.org/wiki/Atomic_orbital#Shapes_of_orbitals The "Shapes of Orbitals" section should help the understanding. I suppose by orbital you mean an atomic orbital, which is basically nothing else than a designated area in which the ...

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Free neutrons are unstable, with a half life of about 10 minutes. They almost always decay via $\beta$-decay: $$\text{n}^0 \rightarrow \text{p}^+ + \text{e}^-+\bar{\nu}_\text{e}$$ This is the same $\beta$-decay that occurs in unstable nuclei, and is possible outside the nucleus because free neutrons are more massive than free protons. The situation in a ...

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In physics, fundamental particles are typically treated as point particles. In this approximation, they have no size or shape whatsoever. They sort of have a location, but we can never exactly pinpoint this location in space, because quantum mechanics tells us that a particle never has an exact location. The classical model of the electron does yield a ...

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A moderate amount, or very little, depending on your perspective. The quantum leap is an outdated theoretical construct. The maths of modern QM do not require instantaneous jumps to be performed by electrons shifting between energy levels, or in any other situation. We now understand that all things including the electron are dynamically evolving smoothly ...

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From this wikipedia article: In quantum chromodynamics, the modern theory of the nuclear force, most of the mass of the proton and the neutron is explained by special relativity. The mass of the proton is about 80–100 times greater than the sum of the rest masses of the quarks that make it up, while the gluons have zero rest mass. The extra energy of the ...

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Has subatomic particles ever been seen in a state of superposition as the other answers state one cannot label an individual particle until measurement of some of its variables. After measurement the information is a specific value of (x,y) or (p,E) at time t. or do we just detect information like qubits about the state of the particle? Just ...

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Oh yes, certainly. Of course there is, by your definition, no way to determine this, even in principle. Since these "ghost atoms" are unobservable, they emit no radiation that we can sense. Unlike dark matter, whose existence we have deduced from gravitational effects, they do not affect us gravitationally. They do not collide with regular atoms, and they do ...

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