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Cosmon
In physical cosmology, a cosmon or cosmonium is a hypothetical form of matter. The idea was originally proposed by Georges Lemaître, who suggested the concept of a "primeval atom" (''L'Hypothèse de l'Atome Primitif'') 1946, leading up to the theory of the Big Bang. He illustrated the idea by imagining an object 30 times larger than the volume of the sun containing all the matter of the Universe. Its density would be around 10^\text^. In his view, this occurred somewhere between 20 and 60 billion years ago. The idea of a primeval “super-atom” lived on and was developed by Maurice Goldhaber in 1956. In his proposal, there would have been a point, which had been called a universon, that would have collapsed into a cosmon and anti-cosmon pair. Goldhaber's theory suffered from the fact that matter existed at all if equal amounts of matter and antimatter were formed in the Big Bang. One explanation for this is the asymmetry of matter, meaning that there could have been slightly m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maurice Goldhaber
Maurice Goldhaber (April 18, 1911 – May 11, 2011) was an American physicist, known for the 1957 (with Lee Grodzins and ) that established that neutrinos have negative helicity. Early life and childhood He was born on April 18, 1911, in Lemberg, Austria, now called Lviv, Ukraine to a Jewish family. His great-grandfather Gershon Goldhaber was a rabbi. His son Alfred Goldhaber is a professor at the C. N. Yang Institute for Theoretical Physics at SUNY Stony Brook. His grandson, David Goldhaber-Gordon is a Physics Professor at Stanford University. Education After beginning his physics studies at the University of Berlin, he earned his doctorate at Cambridge University in 1936, belonging to Magdalene College. Career In 1934, working at the Cavendish Laboratory in Cambridge, England he and James Chadwick, through what they called the nuclear photo-electric effect, established that the neutron has a great enough mass over the proton to decay. He moved to the University of Illi ... [...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 in 1915 with the development 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 Sliph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georges Lemaître
Georges Henri Joseph Édouard Lemaître ( ; ; 17 July 1894 – 20 June 1966) was a Belgian Catholic priest, theoretical physicist, and mathematician who made major contributions to cosmology and astrophysics. He was the first to argue that the recession of galaxies is evidence of an expanding universe and to connect the observational Hubble–Lemaître law with the solution to the Einstein field equations in the general theory of relativity for a homogenous and isotropic universe. That work led Lemaître to propose what he called the "hypothesis of the primeval atom", now regarded as the first formulation of the Big Bang theory of the origin of the universe. Lemaître studied engineering, mathematics, physics, and philosophy at the Catholic University of Louvain and was ordained as a priest of the Archdiocese of Mechelen in 1923. His ecclesiastical superior and mentor, Cardinal Désiré-Joseph Mercier, encouraged and supported his scientific work, allowing Lemaître to trave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Bang
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models based on the Big Bang concept explain a broad range of phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure. The uniformity of the universe, known as the horizon and flatness problems, is explained through cosmic inflation: a phase of accelerated expansion during the earliest stages. A wide range of empirical evidence strongly favors the Big Bang event, which is now essentially universally accepted.: "At the same time that observations tipped the balance definitely in favor of the relativistic big-bang theory, ..." Detailed measurements of the expansion rate of the universe place the Big Bang singularity at an estimated billion years ago, which is considered the age of the universe. Extrapolating this cosmic expansion backward in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universe
The universe is all of space and time and their contents. It comprises all of existence, any fundamental interaction, physical process and physical constant, and therefore all forms of matter and energy, and the structures they form, from sub-atomic particles to entire Galaxy filament, galactic filaments. Since the early 20th century, the field of cosmology establishes that space and time emerged together at the Big Bang ago and that the Expansion of the universe, universe has been expanding since then. The observable universe, portion of the universe that can be seen by humans is approximately 93 billion light-years in diameter at present, but the total size of the universe is not known. Some of the earliest Timeline of cosmological theories, cosmological models of the universe were developed by ancient Greek philosophy, ancient Greek and Indian philosophy, Indian philosophers and were geocentric model, geocentric, placing Earth at the center. Over the centuries, more prec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimatter
In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding subatomic particle, particles in "ordinary" matter, and can be thought of as matter with reversed charge and parity, or going backward in time (see CPT symmetry). Antimatter occurs in natural processes like cosmic ray collisions and some types of radioactive decay, but only a tiny fraction of these have successfully been bound together in experiments to form antiatoms. Minuscule numbers of antiparticles can be generated at particle accelerators, but total artificial production has been only a few nanograms. No Macroscopic scale, macroscopic amount of antimatter has ever been assembled due to the extreme cost and difficulty of production and handling. Nonetheless, antimatter is an essential component of widely available applications related to beta decay, such as positron emission tomography, radiation therapy, and industrial imaging. In theory, a particle and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baryogenesis
In physical cosmology, baryogenesis (also known as baryosynthesis) is the physical process that is hypothesized to have taken place during the early universe to produce baryonic asymmetry, the observation that only matter (baryons) and not antimatter (antibaryons) is detected in universe other than in cosmic ray collisions. Since it is assumed in cosmology that the particles we see were created using the same physics we measure today, and in particle physics experiments today matter and antimatter are always symmetric, the dominance of matter over antimatter is unexplained. A number of theoretical mechanisms are proposed to account for this discrepancy, namely identifying conditions that favour symmetry breaking and the creation of normal matter (as opposed to antimatter). This imbalance has to be exceptionally small, on the order of 1 in every (≈) particles a small fraction of a second after the Big Bang. After most of the matter and antimatter was annihilated, what remaine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Dehmelt
Hans Georg Dehmelt (; 9 September 1922 – 7 March 2017) was a German and American physicist, who was awarded a Nobel Prize in Physics in 1989, for co-developing the ion trap technique (Penning trap) with Wolfgang Paul, for which they shared one-half of the prize (the other half of the Prize in that year was awarded to Norman Foster Ramsey). Their technique was used for high precision measurement of the electron magnetic moment. Biography At the age of ten Dehmelt enrolled in the Berlinisches Gymnasium zum Grauen Kloster, a Latin school in Berlin, where he was admitted on a scholarship. After graduating in 1940, he volunteered for service in the German Army, which ordered him to attend the University of Breslau to study physics in 1943. After a year of study he returned to army service and was captured during the Battle of the Bulge. After his release from an American prisoner of war camp in 1946, Dehmelt returned to his study of physics at the University of Göttingen, where he ... [...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 in 1915 with the development 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 Sliph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
