Sharma | Spring 24 1
BYRNE SEMINAR SPRING 2024 | Understanding Particle Physics
Particle physics is the branch of physics that explores the fundamental constituents of matter
and the forces that govern their interactions. It delves into the smallest scales of the universe,
seeking to understand the nature of particles and the fundamental forces that shape the
cosmos. At its core, particle physics aims to answer questions about the fundamental building
blocks of the universe and the underlying laws that govern their behaviour.
The Standard Model of particle physics serves as the theoretical framework for understanding
the fundamental particles and their interactions. According to this model, matter is composed of
two broad categories of particles: fermions and bosons. Fermions are particles that make up
matter, including quarks and leptons, while bosons are force-carrying particles responsible for
mediating interactions between particles.
Quarks are elementary particles that combine to form composite particles called hadrons. There
are six types, or flavors, of quarks: up, down, charm, strange, top, and bottom. Protons and
neutrons, which make up the atomic nucleus, are composed of combinations of quarks. For
example, a proton consists of two up quarks and one down quark, while a neutron consists of
one up quark and two down quarks.
Leptons, on the other hand, are another class of fermions that do not experience the strong
nuclear force. The most well-known leptons are the electron, muon, and tau, along with their
corresponding neutrinos. Electrons are stable and commonly found in atoms, while muons and
taus are heavier versions of electrons that decay into lighter particles.
