Luminiferous aetherLuminiferous aether or ether ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light. It was invoked to explain the ability of the apparently wave-based light to propagate through empty space (a vacuum), something that waves should not be able to do. The assumption of a spatial plenum (space completely filled with matter) of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light.
Quantum gravityQuantum gravity (QG) is a field of theoretical physics that seeks to describe gravity according to the principles of quantum mechanics. It deals with environments in which neither gravitational nor quantum effects can be ignored, such as in the vicinity of black holes or similar compact astrophysical objects, such as neutron stars as well as in the early stages of the universe moments after the Big Bang Three of the four fundamental forces of nature are described within the framework of quantum mechanics and quantum field theory: the electromagnetic interaction, the strong force, and the weak force; this leaves gravity as the only interaction that has not been fully accommodated.
Muon neutrinoThe muon neutrino is an elementary particle which has the symbol _Muon neutrino and zero electric charge. Together with the muon it forms the second generation of leptons, hence the name muon neutrino. It was discovered in 1962 by Leon Lederman, Melvin Schwartz and Jack Steinberger. The discovery was rewarded with the 1988 Nobel Prize in Physics. The muon neutrino or "neutretto" was hypothesized to exist by a number of physicists in the 1940s. The first paper on it may be Shoichi Sakata and Takesi Inoue's two-meson theory of 1942, which also involved two neutrinos.
Big BangThe Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models of the Big Bang explain the evolution of the observable universe from the earliest known periods through its subsequent large-scale form. These models offer a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background (CMB) radiation, and large-scale structure.
Galaxy rotation curveThe rotation curve of a disc galaxy (also called a velocity curve) is a plot of the orbital speeds of visible stars or gas in that galaxy versus their radial distance from that galaxy's centre. It is typically rendered graphically as a plot, and the data observed from each side of a spiral galaxy are generally asymmetric, so that data from each side are averaged to create the curve. A significant discrepancy exists between the experimental curves observed, and a curve derived by applying gravity theory to the matter observed in a galaxy.
Anaximenes of MiletusAnaximenes of Miletus (ˌænækˈsɪməˌniːz; Ἀναξιμένης ὁ Μιλήσιος; 586/585-526/525 BC) was an Ancient Greek, Pre-Socratic philosopher from Miletus in Anatolia (modern-day Turkey) active in the 6th century BC. He was the last of the three philosophers of the Milesian School, regarded by historians as the first philosophers of the Western world. Anaximenes is best known and identified as a younger friend or student of Anaximander, who was himself taught by the first philosopher in the Greek tradition, Thales, one of the Seven Sages of Greece.
Tau neutrinoThe tau neutrino or tauon neutrino is an elementary particle which has the symbol _Tauon neutrino and zero electric charge. Together with the tau (τ), it forms the third generation of leptons, hence the name tau neutrino. Its existence was immediately implied after the tau particle was detected in a series of experiments between 1974 and 1977 by Martin Lewis Perl with his colleagues at the SLAC–LBL group. The discovery of the tau neutrino was announced in July 2000 by the DONUT collaboration (Direct Observation of the Nu Tau).
Thales of MiletusThales of Miletus (ˈθeɪliːz ; Θαλῆς; 626/623 -548/545 BC) was an Ancient Greek pre-Socratic philosopher from Miletus in Ionia, Asia Minor. Thales was one of the Seven Sages, founding figures of Ancient Greece, and credited with the saying "know thyself" which was inscribed on the Temple of Apollo at Delphi. Many regard him as the first philosopher in the Greek tradition, breaking from the prior use of mythology to explain the world and instead using natural philosophy.
False vacuum decayIn quantum field theory, a false vacuum is a hypothetical vacuum that is relatively stable, but not in the most stable state possible. This condition is known as metastable. It may last for a very long time in that state, but could eventually decay to the more stable state, an event known as false vacuum decay. The most common suggestion of how such a decay might happen in our universe is called bubble nucleation – if a small region of the universe by chance reached a more stable vacuum, this "bubble" (also called "bounce") would spread.
Jain philosophyJain philosophy or Jaina philosophy refers to the ancient Indian philosophical system of the Jain religion. It comprises all the philosophical investigations and systems of inquiry that developed among the early branches of Jainism in ancient India following the parinirvāṇa of Mahāvīra (5th century BCE). One of the main features of Jain philosophy is its dualistic metaphysics, which holds that there are two distinct categories of existence: the living, conscious, or sentient beings (jīva) and the non-living or material entities (ajīva).
