# Introduction

In order to explore any field of physics properly, one must understand the terminology and specific vocabulary. We encourage you to consult this glossary any time you are unfamiliar with a word or concept.

# Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Blackbody: a structure that completely absorbs all light that strikes it, meaning that there is no penetration or reflection of light through its surface
Black hole: theoretical structure that contains a massive amount of mass in a relatively small area, thus black holes are extremely powerful and can even prevent the escape of light
Boson(s): particles, which are named after Indian physicist Satyendra Bose, that have integral spin
Bosonic string theory: string theory that involves twenty-six dimensions and includes only bosons
Brane: short for “membrane,” this structure can have anywhere from negative one to ten dimensions; open strings can attach themselves to this structure
Calabi-yau shape: six-dimensional structure that could effectively incorporate six undetectable extra dimensions into the physical world
Classical mechanics: also called “Newtonian mechanics,” the field of work based on Newton’s laws of motion
Duality: theoretical models that are used to show the similarity between two apparently dissimilar things
Electromagnetism: the field dealing with the relationship between electricity and magnetism
Electron: subatomic particle that has a negative charge and orbits the nucleus on various energy levels
Electroweak force: force that combines electromagnetism and the weak force into only one force
Equivalence principle: component of general relativity that states that the effect of gravity is equivalent to the effect of acceleration
Fermion(s): particles, which are named after Italian physicist Enrico Fermi, that have half-integral spin
Fluid dynamics: the study of the motion of liquids and gases
General relativity: theory proposed by Albert Einstein that states that gravitation and acceleration are essentially the same thing
Gluon: particle that comprises the strong nuclear force
Grand unification theory (GUT): theory that would incorporate the strong and electroweak force within on single theory
Graviton: the fundamental, yet theoretical particle that is responsible for constituting the force of gravity
Hadron(s): a particle that is influenced by the strong nuclear force; hadrons are futher classified as either bosons or fermions
Kaluza - Klein theory: theory that attempts to unify electromagnetism and general relativity by introducing a fifth dimension
Lepton(s): a subatomic particle that is not composed of quarks
M-Theory: theory proposed in 1994 by Edward Witten that combines the five superstring theories into just one theory primarily with the use of dualities
Matrix mechanics: the field that uses matrices to study matter
Neutrino: fundamental particle that contains very little mass and is only affected by gravity and the weak force (and not by electromagnetism or the strong force); the three types of neutrinos are the electron, muon, and tau neutrino
Paul exclusion principle: principle that states that no two fermions can have the same four sets of quantum description (or state)
Perturbation: approximations used in physics that are used to solve mathematical problems
Photo-electric effect: the release of electrons from a surface due to the absorption of electromagnetic radiation; Albert Einstein’s 1921 Nobel Prize in Physics was for his work on this effect
Photon: a packet or particle of light that makes up electromagnetic radiation
Quantum: a structure that (in this case) represents the smallest physical manifestation of a substance (energy, for example)
Quantum chromodynamics (QCD): the field that studies the strong force and its associated physical parts
Quantum electrodynamics (QED): the field that deals with electromagnetism in relation to quantum field theory
Quantum field theory (QFT): the field that integrates quantum mechanics with fields
Quantum gravity: field of physics that is concerned with unifying general relativity and quantum mechanics
Quantum mechanics: study of physical structures, such as atoms and molecules, that is more precise than classical mechanics
Quark: the smallest structure in particle physics; there are six quarks: up, down, top, bottom, strange, and charm
Schrödinger equation: developed by Austrian Erwin Schrodinger, this equation is a significant equation in quantum mechanics
Standard Model: the model that describes the physical structures incorporated with the forces of electromagnetism, the strong force, and the weak force
Special Relativity: theory proposed by Albert Einstein that deals with space and time; it asserts that the speed of light is constant and differs from general relativity in its failure to incorporate gravity
String: one-dimensional structure that is the fundamental unit in string theory; some examples of strings include open, closed, and heterotic strings>
String theory: theoretical description of the physical world that is based on tiny, one-dimensional strings
Strong (nuclear) force: one of the four fundamental forces of particle physics that allows for the attraction between quarks within the nucleus; this force is responsible for the formation of hadrons
Superstring: a string that obeys the laws of supersymmetry
Supersymmetry: the field of particle physics that explains that there is an underlying symmetry between bosons and fermions
Theory of Everything: a theoretical theory that would explain all the fundamental particles and forces in the universe
Thermodynamics: the study of how heat and energy interact and are related
Wave mechanics: based on the study of the interaction of waves; this field is a form of quantum theory (or quantum mechanics)
Weak force: one of the four fundamental forces of particle physics that incorporates neutrinos and antineutrinos and is a component of beta decay; the weak force is much weaker (109 times weaker) than the strong force