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Beta

Second letter of the Greek alphabet

Beta (UK: /ˈbtə/, US: /ˈbtə/ ; uppercase Β, lowercase β, or cursive ϐ; Ancient Greek: βῆτα, romanized: bē̂ta or Greek: βήτα, romanized: víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Ancient Greek, beta represented the voiced bilabial plosive IPA: [b]. In Modern Greek, it represents the voiced labiodental fricative IPA: [v], while IPA: [b] in borrowed words is instead commonly transcribed as μπ. Letters that arose from beta include the Roman letter B and the Cyrillic letters Б and В.

01Name

Like the names of most other Greek letters, the name of beta comes from the acrophonic name of the corresponding letter in Phoenician, which was the common Semitic word *bayt ('house', compare Arabic: بيت bayt and Hebrew: בית báyit). In Greek, the name was βῆτα bêta, pronounced [bɛ̂ːta] in Ancient Greek. It is spelled βήτα in modern monotonic orthography and pronounced [ˈvita].

The Greek alphabet on an ancient black figure vessel, with the characteristically angular beta of the time
The Greek alphabet on an ancient black figure vessel, with the characteristically angular beta of the time

02History

The letter beta was derived from the Phoenician letter beth .

The letter Β had the largest number of highly divergent local forms. Besides the standard form (either rounded or pointed, ), there were forms as varied as (Gortyn), and (Thera), (Argos), (Melos), (Corinth), (Megara, Byzantium), and (Cyclades).

03Typography

In some high-quality typesetting, especially in the French tradition, a typographic variant of the lowercase letter without a descender is used within a word for ancient Greek: βίβλος is printed βίϐλος.

In typesetting technical literature, it is a commonly made mistake to use the German letter ß (a s-z or s-s ligature) as a replacement for β. The two letters resemble each other in some fonts, but they are unrelated.

04Uses

Algebraic numerals

In the system of Greek numerals, beta has a value of 2. Such use is denoted by a number mark: Β′.

Computing

Finance

Beta is used in finance as a measure of investment portfolio risk.

International Phonetic Alphabet

In the International Phonetic Alphabet, Greek minuscule beta denotes a voiced bilabial fricative [β].

A superscript version may also indicate a compressed vowel, like [ɯᵝ].

Meteorology

Beta has twice been used to name an Atlantic Basin tropical cyclone:

Mathematics and science

  • Beta is often used to denote a variable in mathematics and physics, where it often has specific meanings for certain applications.
  • Some uses of beta in math include:
  • Some uses of beta in physics and engineering include:
    • In spaceflight, beta angle describes the angle between the orbit plane of a spacecraft or other body and the vector from the sun.
    • In nuclear physics, β is used for a beta particle (an unbound energetic electron or positron).
    • In statistical thermodynamics, a quantity known as thermodynamic beta expresses how the entropy of system responds to a small increase in temperature.
  • β is also used for naming in biology. For example, e.g. β-Carotene, a primary source of provitamin A; Β Cells in pancreatic islets, which produce insulin; and beta sheet, a common motif in protein secondary structure.
  • The uppercase letter beta is not generally used as a symbol because it tends to be rendered identically to the uppercase Latin B.

Rock climbing terminology

The term "beta" refers to advice on how to successfully complete a particular climbing route, boulder problem, or crux sequence.

Slang

Beta male, or simply beta, is a slang term for men derived from the designation for beta animals in ethology, along with its counterpart, alpha male. The term has been used as a pejorative self-identifier among members of manosphere communities, particularly incels, who do not believe they are assertive or traditionally masculine, and feel overlooked by women. It is also used to negatively describe other men who are not assertive, particularly in heterosexual relationships.

Videotape formats

"Beta" can be used to refer to several consumer and professional videotape formats developed by Japan's Sony Corporation. Although similarly named, they are very different in function and obsolescence.

  • Betamax was the name of a domestic videotape format developed in the 1970s and 1980s. It competed with the Video Home System (VHS) format developed by the Japanese Victor Company, to which it eventually succumbed. The Betamax format was also marketed Betacord by (Sanyo); some cassettes were simply labeled "Beta", and the logo was a lower-case beta. Betamax lost in the market and is an oft-used example of a technically superior solution that failed due to market forces.
  • Betacam, including Beta SP and DigiBeta, is a family of professional videotape formats launched in 1982 that was the de facto standard for professional video, advertising, and television production through the 2000s. The formats outlasted analog NTSC television, and their scarcity today is because the industry has moved to HD formats.

05Unicode

  • U+0392 Β GREEK CAPITAL LETTER BETA (Β)
  • U+03B2 β GREEK SMALL LETTER BETA (β) (\beta in TeX)
  • U+03D0 ϐ GREEK BETA SYMBOL
  • U+1D5D MODIFIER LETTER SMALL BETA
  • U+1D66 GREEK SUBSCRIPT SMALL LETTER BETA
  • U+1DE9 COMBINING LATIN SMALL LETTER BETA
  • U+2C82 COPTIC CAPITAL LETTER VIDA
  • U+2C83 COPTIC SMALL LETTER VIDA
  • U+333C SQUARE BEETA (Japanese square katakana of ベータ bēta)
  • U+A7B4 LATIN CAPITAL LETTER BETA
  • U+A7B5 LATIN SMALL LETTER BETA
  • U+10381 𐎁 UGARITIC LETTER BETA

These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style:

  • U+1D6A9 𝚩 MATHEMATICAL BOLD CAPITAL BETA
  • U+1D6C3 𝛃 MATHEMATICAL BOLD SMALL BETA
  • U+1D6E3 𝛣 MATHEMATICAL ITALIC CAPITAL BETA
  • U+1D6FD 𝛽 MATHEMATICAL ITALIC SMALL BETA
  • U+1D71D 𝜝 MATHEMATICAL BOLD ITALIC CAPITAL BETA
  • U+1D737 𝜷 MATHEMATICAL BOLD ITALIC SMALL BETA
  • U+1D757 𝝗 MATHEMATICAL SANS-SERIF BOLD CAPITAL BETA
  • U+1D771 𝝱 MATHEMATICAL SANS-SERIF BOLD SMALL BETA
  • U+1D791 𝞑 MATHEMATICAL SANS-SERIF BOLD ITALIC CAPITAL BETA
  • U+1D7AB 𝞫 MATHEMATICAL SANS-SERIF BOLD ITALIC SMALL BETA
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Sources and credits

This article is adapted from the Wikipedia article Beta, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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