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Meet the people whose lives, choices and achievements shaped the journey.
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Wilmington, North Carolina once had a thriving Black middle class and an elected interracial government. In 1898 white supremacists used violence to overthrow that government, kill Black residents and drive many others from the city.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
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Tau (/ˈtaʊ, ˈtɔː, ˈtɒ/ ⓘ;[1] uppercase Τ, lowercase τ or τ; Greek: ταυ [taf]) is the nineteenth letter of the Greek alphabet, representing the voiceless dental or alveolar plosive IPA: [t]. In the system of Greek numerals, it has a value of 300.
The name in English is pronounced /taʊ/ or /tɔː/,[2] and in Greek it is [taf].[3][4] This is because the pronunciation of the combination of Greek letters αυ can have the pronunciation of either [ai], [av] or [af], depending on what follows and if a diaeresis is present on the second vowel or an accent mark is present on the first vowel in Greek orthography.
Tau was derived from the Phoenician letter taw 
(𐤕).[5] Letters that arose from tau include Latin T and Cyrillic Te (Т, т).
The lower-case letter τ is used as a symbol for:
For the Greek and Coptic letter tau:[25]
A function τ(n) related to the divisor function σ(n), also sometimes called Ramanujan's tau function.
The Thue–Morse sequence, also called the Morse–Thue sequence or Prouhet–Thue–Morse sequence (Allouche and Cosnard 2000), is one of a number of related sequences of numbers obtained from the parities of the counts of 1's in the binary representation of the nonnegative integers.
τ shear stress
lifetime τ
τ time constant
The symbol also has a number of other different meanings in physics, for example the tau particle, tau neutrino, as a symbol for torque, etc.
τ, τ torque
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Source: Wikipedia. Article content is retrieved live through the MediaWiki API.
Tau ( ; uppercase Τ, lowercase τ or τ; Greek: ταυ [taf]) is the nineteenth letter of the Greek alphabet, representing the voiceless dental or alveolar plosive IPA: [t]. In the system of Greek numerals, it has a value of 300. The name in English is pronounced or , and in Greek it is [taf]. This is because the pronunciation of the combination of Greek letters αυ can have the pronunciation of either [ai], [av] or [af], depending on what follows and if a diaeresis is present on the second vowel or an accent mark is present on the first vowel in Greek orthography. Tau was derived from the Phoenician letter taw (𐤕). Letters that arose from tau include Latin T and Cyrillic Te (Т, т).
Tau Ceti is a single star in the constellation Cetus. Its name is a Bayer designation. Spectrally, this star is similar to the Sun, although it has only about 78% of the Sun's mass. At a distance of just under 12 light-years (3.7 parsecs) from the Solar System, it is a relatively nearby star and the closest solitary G-type star. The star appears stable, with little stellar variation, and is metal-deficient (low in elements other than hydrogen and helium) relative to the Sun. It can be seen with the unaided eye with an apparent magnitude of 3.5. As seen from Tau Ceti, the Sun would be in the northern hemisphere constellation Boötes with an apparent magnitude of about 2.6. Observations have detected more than ten times as much dust surrounding Tau Ceti as is present in the Solar System. Tau Ceti has been an object of interest for exoplanet searches, and a number of candidate planets have been proposed, but as of 2025 there remains no unambiguous evidence of planets. Because of its debris disk, any planet orbiting Tau Ceti would face far more impact events than present day Earth. Despite this hurdle to habitability, its solar analog (Sun-like) characteristics have led to widespread interest in the star. Given its stability, similarity and relative proximity to the Sun, Tau Ceti is consistently listed as a target for the search for extraterrestrial intelligence (SETI).
The tau (τ, ), also called the tau lepton, tau particle or tauon, is an elementary particle similar to the electron, with negative electric charge and a spin of 1/2. Like the electron, the muon, and the three neutrinos, the tau is a lepton, and like all elementary particles with half-integer spin, the tau has a corresponding antiparticle of opposite charge but equal mass and spin. In the tau's case, this is the "antitau" (also called the positive tau). Tau particles are denoted by the symbol τ− and the antitaus by τ+. Tau leptons have a lifetime of 2.9×10−13 s and a mass of 1776.9 MeV/c2 (compared to 105.66 MeV/c2 for muons and 0.511 MeV/c2 for electrons). Because their interactions are very similar to those of the electron, a tau can be thought of as a much heavier version of the electron. Due to their greater mass, tau particles do not emit as much bremsstrahlung (braking radiation) as electrons; consequently they are potentially much more highly penetrating than electrons. Because of its short lifetime, the range of the tau is mainly set by its decay length, which is too small for bremsstrahlung to be noticeable. Its penetrating power appears only at ultra-high velocity and energy (above petaelectronvolt energies), when time dilation extends its otherwise very short path-length. As with the case of the other charged leptons, the tau has an associated tau neutrino, denoted by ντ.
The tau proteins (abbreviated from tubulin associated unit) form a group of six highly soluble protein isoforms produced by alternative splicing from the gene MAPT (microtubule-associated protein tau). They have roles primarily in maintaining the stability of microtubules in axons and are abundant in the neurons of the central nervous system (CNS), where the cerebral cortex has the highest abundance. They are less common elsewhere but are also expressed at very low levels in CNS astrocytes and oligodendrocytes. Degeneration of the nervous system in forms of dementia such as Alzheimer's disease, frontotemporal dementia (FTD) disorders, and Parkinson's disease are associated with tau protein pathology, in which tau abnormally aggregates. The tau proteins were identified in 1975 as heat-stable proteins essential for microtubule assembly, and have since been characterized as intrinsically disordered proteins.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Shirley Chisholm, elected in 1968.
