Career
Becker's research centered on the study of gravity and similar theories, with a particulate interest in string theory, M-theory, and quantum gravity. Becker's work included developing models for superstring compactification and, working with her sister Katrin Becker, she developed one for the Kaluza–Klein theory. [4]
As she accepted her position to be a professor of physics at Texas A&M in 2005, Melanie was given the opportunity to work alongside her sister, Katrin Becker, to further their studies and specialization in string theory. In general, the models that Melanie developed compared the outcomes from standard elementary particle physics and cosmology. [5]
Being distinguished as a Harvard Radcliffe Institute for Advanced Study Science Fellow in 2005, Becker focused her work during her time here on developing models from string theory that could reproduce experimental data measured within particle accelerators in relation to cosmological data. This stems from her graduate research conducted at the European Organization for Nuclear Research (CERN), where the models studied are known as “compactifications of string theory on manifolds with torsion.” [6]
In 2006 Becker, her sister Katrin Becker, and John Schwartz published a graduate-level textbook on string theory and M-theory. [7]
Hosted by the Institute for Advanced Study, Becker was invited as a lecturer for their 2010 Prospects in Theoretical Physics (PiTP) program titled Aspects of Supersymmetry. [8]
M-theory is a theory in physics that unifies all consistent versions of superstring theory. Edward Witten first conjectured the existence of such a theory at a string theory conference at the University of Southern California in 1995. Witten's announcement initiated a flurry of research activity known as the second superstring revolution. Prior to Witten's announcement, string theorists had identified five versions of superstring theory. Although these theories initially appeared to be very different, work by many physicists showed that the theories were related in intricate and nontrivial ways. Physicists found that apparently distinct theories could be unified by mathematical transformations called S-duality and T-duality. Witten's conjecture was based in part on the existence of these dualities and in part on the relationship of the string theories to a field theory called eleven-dimensional supergravity.
String field theory (SFT) is a formalism in string theory in which the dynamics of relativistic strings is reformulated in the language of quantum field theory. This is accomplished at the level of perturbation theory by finding a collection of vertices for joining and splitting strings, as well as string propagators, that give a Feynman diagram-like expansion for string scattering amplitudes. In most string field theories, this expansion is encoded by a classical action found by second-quantizing the free string and adding interaction terms. As is usually the case in second quantization, a classical field configuration of the second-quantized theory is given by a wave function in the original theory. In the case of string field theory, this implies that a classical configuration, usually called the string field, is given by an element of the free string Fock space.
In mathematics and string theory, a conifold is a generalization of a manifold. Unlike manifolds, conifolds can contain conical singularities, i.e. points whose neighbourhoods look like cones over a certain base. In physics, in particular in flux compactifications of string theory, the base is usually a five-dimensional real manifold, since the typically considered conifolds are complex 3-dimensional spaces.
In theoretical physics, F-theory is a branch of string theory developed by Iranian-American physicist Cumrun Vafa. The new vacua described by F-theory were discovered by Vafa and allowed string theorists to construct new realistic vacua — in the form of F-theory compactified on elliptically fibered Calabi–Yau four-folds. The letter "F" supposedly stands for "Father" in relation to "Mother"-theory.
Nathan "Nati" Seiberg is an Israeli American theoretical physicist who works on quantum field theory and string theory. He is currently a professor at the Institute for Advanced Study in Princeton, New Jersey, United States.
Montonen–Olive duality or electric–magnetic duality is the oldest known example of strong–weak duality or S-duality according to current terminology. It generalizes the electro-magnetic symmetry of Maxwell's equations by stating that magnetic monopoles, which are usually viewed as emergent quasiparticles that are "composite", can in fact be viewed as "elementary" quantized particles with electrons playing the reverse role of "composite" topological solitons; the viewpoints are equivalent and the situation dependent on the duality. It was later proven to hold true when dealing with a N = 4 supersymmetric Yang–Mills theory. It is named after Finnish physicist Claus Montonen and British physicist David Olive after they proposed the idea in their academic paper Magnetic monopoles as gauge particles? where they state:
There should be two "dual equivalent" field formulations of the same theory in which electric (Noether) and magnetic (topological) quantum numbers exchange roles.
Tamiaki Yoneya is a Japanese physicist.
In theoretical physics, boundary conformal field theory (BCFT) is a conformal field theory defined on a spacetime with a boundary. Different kinds of boundary conditions for the fields may be imposed on the fundamental fields; for example, Neumann boundary condition or Dirichlet boundary condition is acceptable for free bosonic fields. BCFT was developed by John Cardy.
Igor R. Klebanov is an American theoretical physicist. Since 1989, he has been a faculty member at Princeton University, where he is currently a Eugene Higgins Professor of Physics and the director of the Princeton Center for Theoretical Science. In 2016, he was elected to the National Academy of Sciences. Since 2022, he is the director of the Simons Collaboration on Confinement and QCD Strings.
Renata Elizaveta Kallosh is a Russian-American theoretical physicist. She is a professor of physics at Stanford University, working there on supergravity, string theory and inflationary cosmology.
Warren Siegel is a theoretical physicist specializing in supersymmetric quantum field theory and string theory. He was a professor at the C. N. Yang Institute for Theoretical Physics at Stony Brook University. He retired in Fall of 2022.
Christof Wetterich is a German theoretical physicist. He is known for researches in quintessence, Wetterich equation for Functional renormalization, Asymptotic safety in quantum gravity.
Ruth Ann Watson Gregory is a British mathematician and physicist, currently Head of Department of Physics and Professor of Theoretical Physics at King's College London. Her fields of specialisation are general relativity and cosmology.
Augusto Sagnotti is an Italian theoretical physicist at Scuola Normale.
Gary T. Horowitz is an American theoretical physicist who works on string theory and quantum gravity.
Claus Kalevi Montonen is a Finnish theoretical physicist, most known for his work with British physicist David Olive in proposing the Montonen–Olive duality.
Paul Stephen Aspinwall is a British theoretical physicist and mathematician, who works on string theory and also algebraic geometry.
A. W. Peet is a professor of physics at the University of Toronto. Peet's research interests include string theory as a quantum theory of gravity, quantum field theory and applications of string theory to black holes, gauge theories, cosmology, and the correspondence between anti-de Sitter space and conformal field theories.
Olaf Lechtenfeld is a German mathematical physicist, academic and researcher. He is a full professor at the Institute of Theoretical Physics at Leibniz University, where he founded the Riemann Center for Geometry and Physics.
The spectral dimension is a real-valued quantity that characterizes a spacetime geometry and topology. It characterizes a spread into space over time, e.g. an ink drop diffusing in a water glass or the evolution of a pandemic in a population. Its definition is as follow: if a phenomenon spreads as , with the time, then the spectral dimension is . The spectral dimension depends on the topology of the space, e.g., the distribution of neighbors in a population, and the diffusion rate.
