This is one of the most fascinating and troublesome asymmetry in our Universe. Scientists have spent decades to find an answer to this but this still is a mystery. But before trying to answer this question let’s answer that what is anti-matter?
Anti-Matter is nothing but the normal matter with opposite charge, spin and other quantum numbers. For an atom of matter, the charge on an electron is -1 but for an an atom of anti-matter, the charge on an electron is 1 and here the electron is referred as a positron. Same goes for the proton, for matter the charge on a proton is 1 but for anti-matter, the charge on a proton is -1 which is called as an anti-proton. According to the charge symmetry, there literally is no difference in the appearance of matter and anti-matter. If there is a planet made up of anti-matter then it will look exactly as a normal planet but touching matter and anti-matter doesn’t work same. If a matter particle collides with an anti-matter particle, both of them annihilate leaving 2 photons behind and this reaction is a pure mass to energy conversion which is governed by Einstein’s famous equation of relativity E=mc² (Complete equation-> E²=(mc²)² (pc)²).
This all means that our Universe must have had 2 types of matter at some point of time where matter and anti-matter started annihilating each other and at the end only matter was left. This simply points out that at the beginning of the universe or at the big bang, the no. of matter particles created would be greater than those of Anti-Matter! It turns out that for every 1 billion anti-matter particles there were 1billion and 1 matter particles created!
But here a question arises, is anti-matter gone for good or does it still exists in a corner of the universe? Well the answer turns out to be an interesting one. Universe is actually made up of quantum fields, it is filled with negative energy and fluctuations in quantum fields produces some weird things which we call virtual particles. These particles are popped into existence without anyone’s help. These particles always pops into existence in pairs. A pair here consists of a particle and it’s corresponding anti-particle. These two then again combine to annihilate each other.
Anti-matter is also produced in a process called as Beta decay. Leptons are elementary particles with half integer spin, these particles are fermions and are not made up of quarks. Anti-Leptons like positron (anti-electron) and anti-neutrinos are formed in such decay processes but again are destroyed immediately after creation due to the abundance of matter. Anti-particles are also present and trapped inside Earth’s magnetic field and Van-Allen Belts. They are formed when cosmic rays interact with our atmosphere. Anti-particles are also formed during very intense lightning strikes but are really rare.
Anti-matter has also been created in big labs like the LHC or Large Hadron Collider. Scientists at BASE (Baryon-anti baryon symmetry experiments) are constantly working to know this species of matter even better. Anti-matter is also one of the most dangerous things known to us due to pure matter to energy transformation. As Einstein’s equation suggests, even the smallest amount of Anti-Matter would produce immense energy due to c² factor which is equal to the square of 299,792,458!!
Now let us return to our original question which arises here, why was matter in abundance? Why wasn’t there a symmetrical distribution of matter and anti-matter? These are the questions that still remain unsolved and believe me, if you know the correct answer you might just get a Nobel prize.
Big bang should had created equal amount of matter and anti-matter but that doesn’t seems true. For some reasons, matter was created more than anti-matter which is the reason that we live in a world full of matter.
The P or parity symmetry is also violated by weak nuclear force which was reduced by the results of a very interesting experiment. These reasons give us a bit of information about this huge anomaly bit still can’t explain it completely. We still are looking for a proper reason with an even proper explanation to end this huge question. So there is no proper answer to the question asked, atleast not till now, we’ve got bits and pieces that we still need to rearrange to put this question aside for good.
For production of more baryons or particles than anti-particles CP symmetry that is Charge and Parity symmetry must be violated so that our Universe favours normal matter. This was seen in CERN where K meson (a type of meson which is a particle composed of a quark and an anti-quark (quark,leptons and bosons are the building blocks of an atom)) was seen oscillating between a particle and an anti-particle, experiments show that K meson and B meson have more chances to convert to a particle than to an anti-particle thus giving a proof for CP symmetry violation which could be considered as a reason for matter’s abundance.