The Standard Model Of Particle Physics

The standard model of particle physics is a model which organises all the fundamental particles discovered till now. It explains how the fundamental particles are related to the three fundamental forces(em force,weak nuclear force,strong nuclear force except gravitational force) out of four. It broadly categorises the fundamental particles as fermions and the bosons. The fermions are the matter particles that build the matter. Fermions are further divided into quarks and leptons.

Quarks:-

The quarks are “up quark”, “down quark”, “charm quark”, “strange quark”, “top quark” and “bottom quark”. The quarks are unstable so they combine to form hadrons. Quarks are of three different colours. The colours are not the physical colours we see in our daily life.In electroydnamics we have two charges as “positive(+)” and “negative(+)”. Similarly, in quantum chromodynamics we have the colour charges as ‘red’, ‘green’ and ‘blue’.

Quarks combine to form hadrons. The hadrons split up into mesons and baryons. The mesons are a combination of 1 quark and 1 anti-quark e.g. pion, kaon etc. The baryons are a combination of 3 quarks. Protons and neutrons are examples of baryons. Proton is the combination of 2 up quarks and 1 down quark. Neutron is the combination of 2 down quarks and 1 up quark. Similarly, there are many baryons e.g. Lambdaꓥ0 (uds), Charmed Lambda ꓥ⁰_c (udc), Bottom Lambda ꓥ⁰_b (udb), etc.

The leptons are “electron”, “muon”, “tauon” and their corresponding neutrinos. The leptons are stable so they don’t combine to form any particles.

In bosons, we have force carrier particles called gauge bosons. These particles mediate the force. The gluon mediates strong nuclear force, photon mediates electromagnetic force, W & Z bosons mediate the weak nuclear force. The Higgs boson is the particle that blesses the massive particles with their mass.