Nu, or ny (; uppercase Ν, lowercase ν; ''ni'' ), is the thirteenth letter of the

Greek alphabet The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC. It was derived from the earlier Phoenician alphabet, and is the earliest known alphabetic script to systematically write vowels as wel ...

, representing the

voiced alveolar nasal The voiced alveolar nasal is a type of consonantal sound used in numerous spoken languages. The symbol in the International Phonetic Alphabet that represents dental, alveolar, and postalveolar nasals is , and the equivalent X-SAMPA symbol i ...

. In the system of

Greek numerals Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, is a numeral system, system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal number (linguistics), ordi ...

it has a value of 50. It is derived from the Phoenician

nun A nun is a woman who vows to dedicate her life to religious service and contemplation, typically living under vows of poverty, chastity, and obedience in the enclosure of a monastery or convent.''The Oxford English Dictionary'', vol. X, page 5 ...

. Its

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

equivalent is N, though the lowercase (

\nu

) resembles the Roman lowercase v. The name of the letter is written in

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

and traditional

Modern Greek Modern Greek (, or , ), generally referred to by speakers simply as Greek (, ), refers collectively to the dialects of the Greek language spoken in the modern era, including the official standardized form of the language sometimes referred to ...

polytonic orthography Greek orthography has used a variety of diacritics starting in the Hellenistic period. The more complex polytonic orthography (), which includes five diacritics, notates Ancient Greek phonology. The simpler monotonic orthography (), introduce ...

, while in

it is written .

Letters Letter, letters, or literature may refer to: Characters typeface * Letter (alphabet), a character representing one or more of the sounds used in speech or none in the case of a silent letter; any of the symbols of an alphabet * Letterform, the g ...

that arose from nu include Roman N and

Cyrillic script The Cyrillic script ( ) is a writing system used for various languages across Eurasia. It is the designated national script in various Slavic languages, Slavic, Turkic languages, Turkic, Mongolic languages, Mongolic, Uralic languages, Uralic, C ...

En.

Symbology

The lower-case letter is used as a symbol in many

academic field An academic discipline or academic field is a subdivision of knowledge that is taught and researched at the college or university level. Disciplines are defined (in part) and recognized by the academic journals in which research is published, a ...

s. Uppercase nu is not used, because it appears identical to Latin N. * Mathematics: **

Degrees of freedom In many scientific fields, the degrees of freedom of a system is the number of parameters of the system that may vary independently. For example, a point in the plane has two degrees of freedom for translation: its two coordinates; a non-infinite ...

statistics Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...

. ** The

greatest fixed point In order theory, a branch of mathematics, the least fixed point (lfp or LFP, sometimes also smallest fixed point) of a function (mathematics), function from a partially ordered set ("poset" for short) to itself is the fixed point (mathematics), f ...

of a function, as commonly used in the μ-calculus. ** Free names of a process, as used in the

π-calculus In theoretical computer science, the -calculus (or pi-calculus) is a process calculus. The -calculus allows channel names to be communicated along the channels themselves, and in this matter, it is able to describe concurrent computations whose ...

. ** One of the Greeks in

mathematical finance Mathematical finance, also known as quantitative finance and financial mathematics, is a field of applied mathematics, concerned with mathematical modeling in the financial field. In general, there exist two separate branches of finance that req ...

, known as "vega". ** The reciprocal of 1 plus the interest rate in finance. ** The -adic valuation or -adic order of a number. *Physics: **

Kinematic viscosity Viscosity is a measure of a fluid's rate-dependent drag (physics), resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for e ...

fluid mechanics Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasma (physics), plasmas) and the forces on them. Originally applied to water (hydromechanics), it found applications in a wide range of discipl ...

. ** The

frequency Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio ...

of a wave in physics and other fields; sometimes also

spatial frequency In mathematics, physics, and engineering, spatial frequency is a characteristic of any structure that is periodic across position in space. The spatial frequency is a measure of how often sinusoidal components (as determined by the Fourier tra ...

;

wavenumber In the physical sciences, the wavenumber (or wave number), also known as repetency, is the spatial frequency of a wave. Ordinary wavenumber is defined as the number of wave cycles divided by length; it is a physical quantity with dimension of ...

** The

specific volume In thermodynamics, the specific volume of a substance (symbol: , nu) is the quotient of the substance's volume () to its mass (): :\nu = \frac It is a mass-specific intrinsic property of the substance. It is the reciprocal of density (rho) ...

thermodynamics Thermodynamics is a branch of physics that deals with heat, Work (thermodynamics), work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed b ...

. **

Poisson's ratio In materials science and solid mechanics, Poisson's ratio (symbol: ( nu)) is a measure of the Poisson effect, the deformation (expansion or contraction) of a material in directions perpendicular to the specific direction of loading. The value ...

, the ratio of strains perpendicular with and parallel with an applied force. ** Any of three kinds of

neutrino A neutrino ( ; denoted by the Greek letter ) is an elementary particle that interacts via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that i ...

in particle physics. ** The number of

neutrons The neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The neutron was discovered by James Chadwick in 1932, leading to the discovery of nuclear fission in 1938, the f ...

released per

fission Fission, a splitting of something into two or more parts, may refer to: * Fission (biology), the division of a single entity into two or more parts and the regeneration of those parts into separate entities resembling the original * Nuclear fissio ...

of an atom in nuclear physics. ** Molecular

vibrational mode A normal mode of a dynamical system is a pattern of motion in which all parts of the system move sinusoidally with the same frequency and with a fixed phase relation. The free motion described by the normal modes takes place at fixed frequencies. ...

, where is the number of the vibration (a label). ** The

true anomaly In celestial mechanics, true anomaly is an angular parameter that defines the position of a body moving along a Keplerian orbit. It is the angle between the direction of periapsis and the current position of the body, as seen from the main focus ...

, an angular parameter that defines the position of a body moving along an orbit (see

orbital elements Orbital elements are the parameters required to uniquely identify a specific orbit. In celestial mechanics these elements are considered in two-body systems using a Kepler orbit. There are many different ways to mathematically describe the same o ...

). *Biology: ** A DNA polymerase found in higher

eukaryotes The eukaryotes ( ) constitute the domain of Eukaryota or Eukarya, organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of ...

and implicated in

translesion synthesis DNA repair is a collection of processes by which a cell (biology), cell identifies and corrects damage to the DNA molecules that encode its genome. A weakened capacity for DNA repair is a risk factor for the development of cancer. DNA is cons ...

. *Chemistry: ** The

stoichiometric coefficient A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and chemical formulas. The reactant entities are given on the left-hand side and the product entities are on the right-hand side with a plus sign be ...

. *Psychology: ** The maximum conditioning possible for an

unconditioned stimulus Classical conditioning (also respondent conditioning and Pavlovian conditioning) is a behavioral procedure in which a biologically potent stimulus (e.g. food, a puff of air on the eye, a potential rival) is paired with a neutral stimulus (e.g. ...

in the Rescorla-Wagner model.

Unicode

Encodings of Greek Nu and Coptic Ni.Unicode Code Charts
Greek and Coptic (Range: 0370-03FF)
/ref> * * ( in TeX) * * * * * * * * * * * *

References

{{DEFAULTSORT:Nu (Letter) Greek letters

Symbology

Unicode

See also

References