The anti-particle corresponding to a proton or an electron is a particle with an equal mass, but an opposite charge. So what is the anti-particle corresponding to a neutron (which does not possess a charge)? And if it is just another neutron, will its collision with the original neutron be as destructive as the collision of a proton with an anti-proton or an electron with an anti-electron?
[Physics] Anti-Particle of Neutron
antimatterneutronssubatomic
Related Solutions
You didn't understand any of these questions right. Antiquarks and their bound states, including the antineutrons, are produced and observed as easily as bread and butter. Lots of details experiments with e.g. antineutrons have been performed, e.g.
Scattering of antineutrons with hydrogen
http://www.sciencedirect.com/science/article/pii/037026939290998J
(this one was done more than 20 years ago) and all these experiments agree with the theoretical predictions. Millions of antiquarks are produced at the LHC each second (when it's running), too.
There's not a tiny doubt that every particle has an antiparticle. For most particles, the antiparticle is different from the original particle. Only "truly neutral" particles such as photons, gravitons, and Higgs bosons (but not neutrons!) have antiparticles that are identical to the original particle. All the antiparticle species to the known particle species have been observed, too.
The neutron always or virtually always decays to a proton, an electron, and an electron antineutrino. There's no doubt about it – this fact can be calculated from the Standard Model and it may experimentally verified, too.
Also, the antineutron can't decay to the same products as the neutron (or vice versa). That would violate the conservation of the baryon number and the conservation of the isospin in the processes based governed by the strong interaction. These conservation laws are "laws in our theories" but we only believe all these laws because there is an overwhelming experimental support for all these things.
It's impractical to measure the neutron-antineutron annihilation because both particles are (equally) unstable. But totally analogous annihilation of antineutrons and protons (see the paper above) – with some light charged products aside from neutral pions – are almost the same thing and indeed, virtually all the rest mass gets converted to pure energy just like in the case of any annihilation.
All the things you doubt – and hundreds of much more advanced, detailed, and accurate insights of a similar kind – are completely indisputable and experimentally verifiable, often very directly.
Here is the elementary particle table from which all others are built up , the standard model of particle physics.
Which shows the conserved quantum numbers that characterize the particles (columns and rows have quantum numbers assigned too) plus the measured masses. The quantum numbers have to "annihilate" to have an annihilation event, i.e. they should become 0 after annihilation. Mass is not a quantum number , it is a "length" in the energy momentum vector of the particles. Conservation of quantum numbers in interactions allow the mass to remain invariant. If quantum numbers are annihilated there is no constraint on the total energy momentum vector other than energy conservation, and the products allow that.
Here is a Feynman diagram of e+e- annihilation
There is no extra energy except the four vector of each incoming lepton. Charge is just a number counting attribute here.
Here is e+e- annihilation when the energies are large enough to create a muon pair
and a more complicated one into b bbar jets
In all these the quantum numbers annihilate on the left and new quantum numbers from 0 create pairs with oposite quantum numbers, according to the probabilities for the interaction at that energy.
In a nutshell: it is the quantum numbers that become annihilated/0 , freeing the energy momentum fourvectors to display their creativity :)
Best Answer
The anti-particle corresponding to a neutron is an anti neutron!
The neutron is made up of one up quark and two down quarks. The anti-neutron is made up of an anti-up quark and two anti-down quarks. Both have zero charge because the charges of the quarks within them balance out.
You are correct that elementary particles with no charge are often their own anti-particles. These tend to be vector bosons; for example the photon and the Z boson are their own anti-particles. The W$^-$ and W$^+$ are each other's anti-particles. It's a bit more complicated with the gluons because they carry a colour charge.
Amongst the fermions there are no particles known that are their own anti-particles. If such particles exist they would obey the Majorana equation and these theoretical particles are known as Majorana fermions.