| The Following Topics Might Appear on Quiz 5 (2021) |
| Antiparticle of a particle has its same mass and spins but opposite charges |
| Particles with half-integral spin (1/2, 3/2,...) are called Fermions |
| Particles with integral spin (0, 1,...) are called Bosons |
| Fermions obey the Pauli Exclusion Principle; Bosons do not. |
| The Standard Model is to particle physics what the Periodic table is to chemistry |
| There are 4 fundamental forces: Strong, Electromagnetic, Weak, Gravity |
| Particles exerts a force on each other by exchanging a force-mediating particle |
| The gluon is the force-mediating particle for the strong force (binds quarks within nucleons and indirectly binds nucleons to each other) |
| The photon is the force-mediating particle for the electromagnetic force (binds electrons to atomic nuclei) |
| The W and Z bosons are the force-mediating particles for the weak force (permits beta decay, which warms the earth's interior) |
| The graviton is the hypothetical force-mediating particle for the gravitational force (binds planets to the sun in the solar system) |
| According to the the Standard Model, the only indivisible fermionic particles are quarks and leptons |
| There are 3 "generations" of quarks and leptons. |
| Particles in Generation 1 ("up" quark, "down" quark, electron, electron neutrino) have the lowest masses and the longest lifetimes. |
| Ordinary matter is composed of Genration 1 particles. |
| Generation 2 & 3 particles are only found in particle accelerator experiments or cosmic rays. |
| Protons and neutrons are each composed of 3 quarks |
| Proton = "up" quark + "up" quark + "down" quark |
| Neutron = "down" quark + "down" quark + "up" quark |
| "up" quarks have an electric charge of +2/3. "down" quarks have an electric charge of -1/3 |
| Quarks do not exist in isolation. [They are either in groups of 3 (e.g. a proton) or 2 (e.g. pi meson)] |
| Electrons, positrons, and neutrinos are all leptons |
| Hadrons are composite particles on which the strong force acts |
| Hadrons are composed of quarks |
| Baryon are hadrons composed of 3 quarks (e.g. proton) |
| Mesons are hadrons composed of 2 quarks (e.g. pi meson) |
| The role of the Higgs Boson in the Standard Model is to endow massive particles with their mass |
| The Large Hadron Collider near Geneva, Switzerland is a $6 billion machine designed to create and detect the Higgs Boson |
| With the discovery of the Higgs boson in 2012, all of the particles predicted by the Standard Model have been discovered. |
| In 1998 astronmers discovered that the expansion of the univese is accelerating |
| At most only 5% of the universe is made of normal matter |
| ~25% of the univese is "dark matter": unknown, invisible matter that only interacts gravitationally |
| ~70% of the universe is "dark energy": an unknown, anti-gravitating substance that is accelerating the expansion of the universe |
| The Standard Model unifies all of the fundamental forces except for gravity |
| Quiz will be: |
| closed book, closed notes. |
| 10 questions |
| 10 minutes long |
| totally conceptual |
| totally multiple choice or T/F |