|
Jerzy Lewandowski
Jerzy Lewandowski is a Polish theoretical physicist who studies quantum gravity. He is a professor of physics at the University of Warsaw. Lewandowski received his doctorate in Warsaw under Andrzej Trautman. He worked closely with Abhay Ashtekar at Pennsylvania State University in the 1990s on the mathematical justification of Loop Quantum Gravity (LQG). Among other things, he was at the Erwin Schrödinger Institute in Vienna and at the Max Planck Institute for Gravitational Physics in Golm near Potsdam. He dealt with cosmological models and the entropy of black holes in the LQG. In 2010 he and his colleagues investigated a scalar field together with the gravitational field as part of LQG and were able to show the origin of a time as the ratio of the scalar to the gravitational field, and the quantization of the gravitational field. Publications * With Ashtekar ''Background independent quantum gravity: a status report'', Classical and Quantum Gravity, Band 21, 2004, R 5Arxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theoretical Physics
Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experimental tools to probe these phenomena. The advancement of science generally depends on the interplay between experimental studies and theory. In some cases, theoretical physics adheres to standards of mathematical rigour while giving little weight to experiments and observations.There is some debate as to whether or not theoretical physics uses mathematics to build intuition and illustrativeness to extract physical insight (especially when normal experience fails), rather than as a tool in formalizing theories. This links to the question of it using mathematics in a less formally rigorous, and more intuitive or heuristic way than, say, mathematical physics. For example, while developing special relativity, Albert Einstein was concerned wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Cosmology
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its Cosmogony, origin, structure, Chronology of the universe, evolution, and ultimate fate.For an overview, see Cosmology as a science originated with the Copernican principle, which implies that astronomical object, celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood. Physical cosmology, as it is now understood, began with the development in 1915 of Albert Einstein's general relativity, general theory of relativity, followed by major observational discoveries in the 1920s: first, Edwin Hubble discovered that the universe contains a huge number of external Galaxy, galaxies beyond the Milky Way; then, work by Vesto Sli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academic Staff Of The University Of Warsaw
An academy (Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary or tertiary higher learning (and generally also research or honorary membership). The name traces back to Plato's school of philosophy, founded approximately 385 BC at Akademia, a sanctuary of Athena, the goddess of wisdom and skill, north of Athens, Greece. Etymology The word comes from the ''Academy'' in ancient Greece, which derives from the Athenian hero, ''Akademos''. Outside the city walls of Athens, the gymnasium was made famous by Plato as a center of learning. The sacred space, dedicated to the goddess of wisdom, Athena, had formerly been an olive grove, hence the expression "the groves of Academe". In these gardens, the philosopher Plato conversed with followers. Plato developed his sessions into a method of teaching philosophy and in 387 BC, established what is known today as the Old Academy. By extension, ''academia'' has come to mean the accumulation, dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loop Quantum Gravity Researchers
Loop or LOOP may refer to: Brands and enterprises * Loop (mobile), a Bulgarian virtual network operator and co-founder of Loop Live * Loop, clothing, a company founded by Carlos Vasquez in the 1990s and worn by Digable Planets * Loop Mobile, an Indian mobile phone operator * Loop, a reusable container program announced in 2019 by TerraCycle Geography * Loop, Germany, a municipality in Schleswig-Holstein * Loop (Texarkana), a roadway loop around Texarkana, Arkansas, United States * Loop, Blair County, Pennsylvania, United States * Loop, Indiana County, Pennsylvania, United States * Loop, West Virginia, United States * Loop 101, a semi-beltway of the Phoenix Metropolitan Area * Loop 202, a semi-beltway of the Phoenix Metropolitan Area * Loop 303, a semi-beltway of the Phoenix Metropolitan Area * Chicago Loop, the downtown neighborhood of Chicago bounded by the elevated railway The Loop ** Loop Retail Historic District, a shopping district in the Chicago Loop * Delmar Loop, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polish Relativity Theorists
Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Poles Poles,, ; singular masculine: ''Polak'', singular feminine: ''Polka'' or Polish people, are a West Slavic nation and ethnic group, who share a common history, culture, the Polish language and are identified with the country of Poland in C ..., people from Poland or of Polish descent * Polish chicken * Polish brothers (Mark Polish and Michael Polish, born 1970), American twin screenwriters Polish may refer to: * Polishing, the process of creating a smooth and shiny surface by rubbing or chemical action ** French polishing, polishing wood to a high gloss finish * Nail polish * Shoe polish * Polish (screenwriting), improving a script in smaller ways than in a rewrite See also * * * Polonaise (other) {{Disambiguation, surname Language and nationality disambiguation pages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Date Of Birth Missing (living People)
Date or dates may refer to: *Date (fruit), the fruit of the date palm (''Phoenix dactylifera'') Social activity *Dating, a form of courtship involving social activity, with the aim of assessing a potential partner **Group dating *Play date, an appointment for children to get together for a few hours * Meeting, when two or more people come together Chronology * Calendar date, a day on a calendar ** Old Style and New Style dates, from before and after the change from the Julian calendar to the Gregorian calendar ** ISO 8601, an international standard covering date formats *Date (metadata), a representation term to specify a calendar date **DATE command, a system time command for displaying the current date *Chronological dating, attributing to an object or event a date in the past **Radiometric dating, dating materials such as rocks in which trace radioactive impurities were incorporated when they were formed Arts, entertainment and media Music *Date (band), a Swedish dans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martin Bojowald
Martin Bojowald (born 18 February 1973 in Jülich) is a German physicist who now works on the faculty of the Penn State Physics Department, where he is a member of the Institute for Gravitation and the Cosmos. Prior to joining Penn State he spent several years at the Max Planck Institute for Gravitational Physics in Potsdam, Germany. He works on loop quantum gravity and physical cosmology and is credited with establishing the sub-field of loop quantum cosmology. Positions * Presently: Professor of Physics, The Pennsylvania State University, Institute for Gravitation and the Cosmos * January 2006 - June 2009: Assistant Professor of Physics, The Pennsylvania State University, Institute for Gravitation and the Cosmos * September 2003 - December 2005: Junior Staff Scientist, Albert-Einstein-Institut * September 2000 - August 2003: Postdoctoral Scholar, Center for Gravitational Physics and Geometry, The Pennsylvania State University Education * June 2000: PhD at RWTH Aachen in Ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donald Marolf
Donald Marolf is a theoretical physicist, a Professor of Physics, and former head of the physics department at the University of California, Santa Barbara. Biography Marolf gained his Ph.D. from University of Texas at Austin in 1992, under Bryce DeWitt with a thesis on '' Green's Bracket Algebras and Their Quantization''.Mathematics Genealogy Projeclisting/ref> His undergraduate-degree is from William Jewell College, in 1987. He is an expert on thermodynamics of black holes, gravitational aspects in string theory, classical- and quantum-gravity. In the past he has worked on the canonical approach to quantum-gravity, lower-dimensional models of quantum-gravity, issues related to quantization of diffeomorphism-invariant theories, and a number of other topics. He has published 113 scientific papers through 2007. See also * Firewall Firewall may refer to: * Firewall (computing), a technological barrier designed to prevent unauthorized or unwanted communications between computer n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantization (physics)
In physics, quantization (in British English quantisation) is the systematic transition procedure from a classical understanding of physical phenomena to a newer understanding known as quantum mechanics. It is a procedure for constructing quantum mechanics from classical mechanics. A generalization involving infinite degrees of freedom is field quantization, as in the "quantization of the electromagnetic field", referring to photons as field " quanta" (for instance as light quanta). This procedure is basic to theories of atomic physics, chemistry, particle physics, nuclear physics, condensed matter physics, and quantum optics. Historical overview In 1901, when Max Planck was developing the distribution function of statistical mechanics to solve ultraviolet catastrophe problem, he realized that the properties of blackbody radiation can be explained by the assumption that the amount of energy must be in countable fundamental units, i.e. amount of energy is not continuous b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravitational Field
In physics, a gravitational field is a model used to explain the influences that a massive body extends into the space around itself, producing a force on another massive body. Thus, a gravitational field is used to explain gravitational phenomena, and is measured in newtons per kilogram (N/kg). Equivalently, it is measured in meters per second squared (m/s2). In its original concept, gravity was a force between point masses. Following Isaac Newton, Pierre-Simon Laplace attempted to model gravity as some kind of radiation field or fluid, and since the 19th century, explanations for gravity have usually been taught in terms of a field model, rather than a point attraction. In a field model, rather than two particles attracting each other, the particles distort spacetime via their mass, and this distortion is what is perceived and measured as a "force". In such a model one states that matter moves in certain ways in response to the curvature of spacetime, and that there is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Hole Thermodynamics
In physics, black hole thermodynamics is the area of study that seeks to reconcile the laws of thermodynamics with the existence of black hole event horizons. As the study of the statistical mechanics of black-body radiation led to the development of the theory of quantum mechanics, the effort to understand the statistical mechanics of black holes has had a deep impact upon the understanding of quantum gravity, leading to the formulation of the holographic principle. Overview The second law of thermodynamics requires that black holes have entropy. If black holes carried no entropy, it would be possible to violate the second law by throwing mass into the black hole. The increase of the entropy of the black hole more than compensates for the decrease of the entropy carried by the object that was swallowed. In 1972, Jacob Bekenstein conjectured that black holes should have an entropy, where by the same year, he proposed no-hair theorems. In 1973 Bekenstein suggested \frac\approx 0 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potsdam
Potsdam () is the capital and, with around 183,000 inhabitants, largest city of the German state of Brandenburg. It is part of the Berlin/Brandenburg Metropolitan Region. Potsdam sits on the River Havel, a tributary of the Elbe, downstream of Berlin, and lies embedded in a hilly morainic landscape dotted with many lakes, around 20 of which are located within Potsdam's city limits. It lies some southwest of Berlin's city centre. The name of the city and of many of its boroughs are of Slavic origin. Potsdam was a residence of the Prussian kings and the German Kaiser until 1918. Its planning embodied ideas of the Age of Enlightenment: through a careful balance of architecture and landscape, Potsdam was intended as "a picturesque, pastoral dream" which would remind its residents of their relationship with nature and reason. The city, which is over 1000 years old, is widely known for its palaces, its lakes, and its overall historical and cultural significance. Landmarks include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
