In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. The Standard Model presently recognizes seventeen distinct particles, twelve fermions and five bosons. As a consequence of flavor and color combinations and antimatter, the fermions and bosons are known to have 48 and 13 variations, respectively. Among the 61 elementary particles embraced by the Standard Model number electrons and other leptons, quarks, and the fundamental bosons. Subatomic particles such as protons, neutrons or muons, which contain two or more elementary particles, are known as composite particles.
In a supersymmetric theory the equations for force and the equations for matter are identical. In theoretical and mathematical physics, any theory with this property has the principle of supersymmetry (SUSY). Dozens of supersymmetric theories exist. Supersymmetry is a spacetime symmetry between two basic classes of particles: bosons, which have an integer-valued spin and follow Bose–Einstein statistics, and fermions, which have a half-integer-valued spin and follow Fermi–Dirac statistics. In supersymmetry, each particle from one class would have an associated particle in the other, known as its superpartner, the spin of which differs by a half-integer. For example, if the electron exists in a supersymmetric theory, then there would be a particle called a selectron, a bosonic partner of the electron. In the simplest supersymmetry theories, with perfectly "unbroken" supersymmetry, each pair of superpartners would share the same mass and internal quantum numbers besides spin. More complex supersymmetry theories have a spontaneously broken symmetry, allowing superpartners to differ in mass.
Brane cosmology refers to several theories in particle physics and cosmology related to string theory, superstring theory and M-theory.
In theoretical physics, the hypothetical particle called the graviscalar or radion emerges as an excitation of general relativity's metric tensor, i.e. gravitational field, but is indistinguishable from a scalar in four dimensions, as shown in Kaluza–Klein theory. The scalar field comes from a component of the metric tensor where the figure 5 labels an additional fifth dimension. The only variations in the scalar field represent variations in the size of the extra dimension. Also, in models with multiple extra dimensions, there exist several such particles. Moreover, in theories with extended supersymmetry, a graviscalar is usually a superpartner of the graviton that behaves as a particle with spin 0. This concept closely relates to the gauged Higgs models.
Warped Passages: Unraveling the Mysteries of the Universe's Hidden Dimensions is the debut non-fiction book by Lisa Randall, published in 2005, about particle physics in general and additional dimensions of space in particular. The book has made it to top 50 at amazon.com, making it the world's first successful book on theoretical physics by a female author. She herself characterizes the book as being about physics and the multi-dimensional universe. The book describes, at a non-technical level, theoretical models Professor Randall developed with the physicist Raman Sundrum, in which various aspects of particle physics are explained in a higher-dimensional braneworld scenario. These models have since generated thousands of citations.
Savas Dimopoulos is a particle physicist at Stanford University. He worked at CERN from 1994 to 1997. Dimopoulos is well known for his work on constructing theories beyond the Standard Model.
Jonathan Richard Ellis is a British theoretical physicist who is currently Clerk Maxwell Professor of Theoretical Physics at King's College London.
Maria Spiropulu is a Greek particle physicist. She is the Shang-Yi Ch'en Professor of Physics at the California Institute of Technology.
Raman Sundrum is an Indian-American theoretical particle physicist. He contributed to the field with a class of models called the Randall–Sundrum models, first published in 1999 with Lisa Randall. Sundrum is a Distinguished University Professor at the University of Maryland and the director of Maryland Center for Fundamental Physics.
Georgi (Gia) Dvali is a Georgian theoretical physicist. He is a professor of theoretical physics at the Ludwig Maximilian University of Munich, a director at the Max Planck Institute for Physics in Munich, and holds a Silver Professorship Chair at the New York University. His research interests include String theory, Extra dimensions, Quantum gravity, and the Early universe.
Sergio Ferrara is an Italian physicist working on theoretical physics of elementary particles and mathematical physics. He is renowned for the discovery of theories introducing supersymmetry as a symmetry of elementary particles and of supergravity, the first significant extension of Einstein's general relativity, based on the principle of "local supersymmetry". He is an emeritus staff member at CERN and a professor emeritus at the University of California, Los Angeles.
Itzhak Bars is a theoretical physicist at the University of Southern California in Los Angeles.
Superstring theory is an attempt to explain all of the particles and fundamental forces of nature in one theory by modeling them as vibrations of tiny supersymmetric strings.
Faheem Hussain, was a Pakistani theoretical physicist and a professor of physics at the Lahore University of Management Sciences (LUMS). A research scientist in the field of superstring theory at the National Center for Physics, Hussain made contributions to the fields of superstring and string theory. He was the first Pakistani physicist to publish a research paper in the field of superstring theory. A social activist and democratic activist, he authored various scientific research papers in peer-reviewed journals.
Gordon Leon Kane is Victor Weisskopf Distinguished University Professor at the University of Michigan and director emeritus at the Leinweber Center for Theoretical Physics (LCTP), a leading center for the advancement of theoretical physics. He was director of the LCTP from 2005 to 2011 and Victor Weisskopf Collegiate Professor of Physics from 2002 - 2011. He received the Lilienfeld Prize from the American Physical Society in 2012, and the J. J. Sakurai Prize for Theoretical Particle Physics in 2017.
Gian Francesco Giudice is an Italian theoretical physicist working at CERN in particle physics and cosmology.
This page is a glossary of terms in string theory, including related areas such as supergravity, supersymmetry, and high energy physics.
Amitava Raychaudhuri is an Indian theoretical particle physicist. He is Professor Emeritus at the Physics Department of the Science College, University of Calcutta where he earlier held the Sir Tarak Nath Palit Chair Professorship. He is the nephew of another renowned Indian physicist, Amal Kumar Raychaudhuri.
Probir Roy is an Indian particle physicist and a former professor at Tata Institute of Fundamental Research. He is also a senior scientist of the Indian National Science Academy at Bose Institute and a former Raja Ramanna fellow of Department of Atomic Energy at Saha Institute of Nuclear Physics.
Valery Anatolyevich Rubakov was a Russian theoretical physicist. His scientific interests included quantum field theory, elementary particle physics, and cosmology. He was affiliated with the Institute for Nuclear Research (INR) of the Russian Academy of Sciences in Moscow.
