Everything began with a bang. A sudden explosion some 13 billion
years ago created everything we are seeing today including
matter,planets,sun,stars and also anything we are actually not seeing
with our naked eyes including dark matter and dark energy.
According to scientists the universe began with the explosion of a very
dense point or singularity that exploded with immense force creating a
lot of matter and propelling it outward consequently generating more
galaxies.Just one second after the big bang,matter was created in form
of neutrons,protons,electrons,anti electrons etc.Now these particles mix
up to make matter,planets,stars etc.But how these particles are
created;are they fundamental or there are more layers to this ;how
energy gets produced from all this?These are some of the questions we
shall discuss during this excerpt.
(Images are used under wikimedia commons)
HOW DOES ANYTHING EXIST ANYWAY?
Post the big bang ,equal number of matter and anti matter should have
been created ,but it didn’t happen.Had it happened,you wouldn’t be
reading this article right now.I mean if there were any symmetry
between particle and anti-particle,they would have annihilated
themselves and there would be only empty space everywhere and the
universe should contain nothing but leftover energy.But everywhere
there is matter.So where are all the anti particles?Where are the
Pair production is the process of creation of a subatomic particle and its
anti-particle from a neutral Boson. Pair production can be production of
an electron and a positron from a photon near the nucleus.
The exact opposite case of pair production is annihilation where a
particle and its corresponding anti-particle collide to produce other
particle or photon.For instance the collision of electron and positron
generates two photon particles.The reason particle and anti-particle
annihilate is that when they collide they cancel out each other’s charge
and parity or we can say they have opposite charge and parity.This
exact concept sets the tone for my initial question about why matter
exists even when they could have annihilated with their corresponding
anti-particles.This is called the matter and anti-matter asymmetry problem.
Experiments of particle to anti-particle conversions show that the
reverse processes don’t occur every time,i.e,for instance neutral mesons
can spontaneously convert into anti-mesons and vice versa ,but it isn’t
always the case.Experiments show that it can occur only in one direction than the other,eventually creating more matter than anti-
matter.So this was one of the many instances where matter is more than the anti matter.
So particle-antiparticle asymmetry is one of those unsolved problems in
physics which has become a big matter of curiosity and research for all
the physicists around the globe and will continue to intrigue particle
physicists and research scholars alike over the years until it’s solved.
Author: SOM ABHISEK.