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Pi (letter)

Index Pi (letter)

Pi (uppercase Π, lowercase π; πι) is the sixteenth letter of the Greek alphabet, representing the sound. [1]

63 relations: Angular frequency, Biology, Buckingham π theorem, Celestial mechanics, Chemical bond, Circle, Circumference, Codex, Codex Petropolitanus (New Testament), Comoving and proper distances, Coptic alphabet, Cursive, Cyrillic script, Diameter, Dimensional analysis, Er (Cyrillic), Euclidean geometry, Fitness (biology), Fluid dynamics, Gamma, Glyph, Gospel, Gothic alphabet, Greek alphabet, Greek numerals, Hadron, Homotopy group, Inflation, Irrational number, List of legal abbreviations, Longitude of the periapsis, Macron (diacritic), Manifold, Omega, Osmotic pressure, P, Pe (Cyrillic), Pe (letter), Peorð, Phoenician alphabet, Pi, Pi bond, Pilcrow, Pion, Plaintiff, Prime-counting function, Product (mathematics), Profit (economics), Projection (relational algebra), Radiative transfer, ..., Reinforcement learning, Relational algebra, Saint Petersburg, Sigma, Single-scattering albedo, Summation, Tangent bundle, TeX, Transcendental number, Uncial script, Unicode, Vorticity, Wind wave. Expand index (13 more) »

Angular frequency

In physics, angular frequency ω (also referred to by the terms angular speed, radial frequency, circular frequency, orbital frequency, radian frequency, and pulsatance) is a scalar measure of rotation rate.

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Biology is the natural science that studies life and living organisms, including their physical structure, chemical composition, function, development and evolution.

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Buckingham π theorem

In engineering, applied mathematics, and physics, the Buckingham theorem is a key theorem in dimensional analysis.

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Celestial mechanics

Celestial mechanics is the branch of astronomy that deals with the motions of celestial objects.

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Chemical bond

A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds.

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A circle is a simple closed shape.

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In geometry, the circumference (from Latin circumferentia, meaning "carrying around") of a circle is the (linear) distance around it.

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A codex (from the Latin caudex for "trunk of a tree" or block of wood, book), plural codices, is a book constructed of a number of sheets of paper, vellum, papyrus, or similar materials.

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Codex Petropolitanus (New Testament)

Codex Petropolitanus, designated by Π or 041 (in the Gregory-Aland numbering), ε 73 (von Soden), is a Greek uncial manuscript of the Gospels, dated palaeographically to the 9th-century.

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Comoving and proper distances

In standard cosmology, comoving distance and proper distance are two closely related distance measures used by cosmologists to define distances between objects.

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Coptic alphabet

The Coptic alphabet is the script used for writing the Coptic language.

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Cursive (also known as script or longhand, among other names) is any style of penmanship in which some characters are written joined together in a flowing manner, generally for the purpose of making writing faster.

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Cyrillic script

The Cyrillic script is a writing system used for various alphabets across Eurasia (particularity in Eastern Europe, the Caucasus, Central Asia, and North Asia).

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In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle.

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Dimensional analysis

In engineering and science, dimensional analysis is the analysis of the relationships between different physical quantities by identifying their base quantities (such as length, mass, time, and electric charge) and units of measure (such as miles vs. kilometers, or pounds vs. kilograms) and tracking these dimensions as calculations or comparisons are performed.

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Er (Cyrillic)

Er (Р р; italics: Р р) is a letter of the Cyrillic script.

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Euclidean geometry

Euclidean geometry is a mathematical system attributed to Alexandrian Greek mathematician Euclid, which he described in his textbook on geometry: the Elements.

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Fitness (biology)

Fitness (often denoted w or ω in population genetics models) is the quantitative representation of natural and sexual selection within evolutionary biology.

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Fluid dynamics

In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids - liquids and gases.

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Gamma (uppercase, lowercase; gámma) is the third letter of the Greek alphabet.

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In typography, a glyph is an elemental symbol within an agreed set of symbols, intended to represent a readable character for the purposes of writing.

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Gospel is the Old English translation of Greek εὐαγγέλιον, evangelion, meaning "good news".

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Gothic alphabet

The Gothic alphabet is an alphabet for writing the Gothic language, created in the 4th century by Ulfilas (or Wulfila) for the purpose of translating the Bible.

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Greek alphabet

The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC.

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Greek numerals

Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, are a system of writing numbers using the letters of the Greek alphabet.

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In particle physics, a hadron (ἁδρός, hadrós, "stout, thick") is a composite particle made of quarks held together by the strong force in a similar way as molecules are held together by the electromagnetic force.

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Homotopy group

In mathematics, homotopy groups are used in algebraic topology to classify topological spaces.

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In economics, inflation is a sustained increase in price level of goods and services in an economy over a period of time.

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Irrational number

In mathematics, the irrational numbers are all the real numbers which are not rational numbers, the latter being the numbers constructed from ratios (or fractions) of integers.

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List of legal abbreviations

It is common practice in legal documents to cite to other publications by using standard abbreviations for the title of each source.

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Longitude of the periapsis

In celestial mechanics, the longitude of the periapsis, also called longitude of the pericenter, of an orbiting body is the longitude (measured from the point of the vernal equinox) at which the periapsis (closest approach to the central body) would occur if the body's orbit inclination were zero.

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Macron (diacritic)

A macron is a diacritical mark: it is a straight bar placed above a letter, usually a vowel.

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In mathematics, a manifold is a topological space that locally resembles Euclidean space near each point.

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Omega (capital: Ω, lowercase: ω; Greek ὦ, later ὦ μέγα, Modern Greek ωμέγα) is the 24th and last letter of the Greek alphabet.

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Osmotic pressure

Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of its pure solvent across a semipermeable membrane.

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P (named pee) is the 16th letter of the modern English alphabet and the ISO basic Latin alphabet.

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Pe (Cyrillic)

Pe (П п; italics: П п) is a letter of the Cyrillic script.

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Pe (letter)

Pe is the seventeenth letter of the Semitic abjads, including Phoenician Pē, Hebrew Pē פ, Aramaic Pē, Syriac Pē ܦ, and Arabic ف (in abjadi order).

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is the rune denoting the sound p (voiceless bilabial stop) in the Elder Futhark runic alphabet, in the Anglo-Saxon rune poem named peorð.

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Phoenician alphabet

The Phoenician alphabet, called by convention the Proto-Canaanite alphabet for inscriptions older than around 1050 BC, is the oldest verified alphabet.

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The number is a mathematical constant.

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Pi bond

In chemistry, pi bonds (π bonds) are covalent chemical bonds where two lobes of an orbital on one atom overlap two lobes of an orbital on another atom.

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The pilcrow (¶), also called the paragraph mark, paragraph sign, paraph, alinea (Latin: a lineā, "off the line"), or blind P, is a typographical character for individual paragraphs.

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In particle physics, a pion (or a pi meson, denoted with the Greek letter pi) is any of three subatomic particles:,, and.

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A plaintiff (Π in legal shorthand) is the party who initiates a lawsuit (also known as an action) before a court.

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Prime-counting function

In mathematics, the prime-counting function is the function counting the number of prime numbers less than or equal to some real number x. It is denoted by (x) (unrelated to the number pi).

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Product (mathematics)

In mathematics, a product is the result of multiplying, or an expression that identifies factors to be multiplied.

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Profit (economics)

In economics, profit in the accounting sense of the excess of revenue over cost is the sum of two components: normal profit and economic profit.

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Projection (relational algebra)

In relational algebra, a projection is a unary operation written as \Pi_(R) where a_1,...,a_n is a set of attribute names.

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Radiative transfer

Radiative transfer is the physical phenomenon of energy transfer in the form of electromagnetic radiation.

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Reinforcement learning

Reinforcement learning (RL) is an area of machine learning inspired by behaviourist psychology, concerned with how software agents ought to take actions in an environment so as to maximize some notion of cumulative reward.

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Relational algebra

Relational algebra, first created by Edgar F. Codd while at IBM, is a family of algebras with a well-founded semantics used for modelling the data stored in relational databases, and defining queries on it.

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Saint Petersburg

Saint Petersburg (p) is Russia's second-largest city after Moscow, with 5 million inhabitants in 2012, part of the Saint Petersburg agglomeration with a population of 6.2 million (2015).

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Sigma (upper-case Σ, lower-case σ, lower-case in word-final position ς; σίγμα) is the eighteenth letter of the Greek alphabet.

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Single-scattering albedo

Single-scattering albedo is the ratio of scattering efficiency to total extinction efficiency (which is also termed "attenuance", a sum of scattering and absorption).

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In mathematics, summation (capital Greek sigma symbol: ∑) is the addition of a sequence of numbers; the result is their sum or total.

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Tangent bundle

In differential geometry, the tangent bundle of a differentiable manifold M is a manifold TM which assembles all the tangent vectors in M. As a set, it is given by the disjoint unionThe disjoint union ensures that for any two points x1 and x2 of manifold M the tangent spaces T1 and T2 have no common vector.

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TeX (see below), stylized within the system as TeX, is a typesetting system (or "formatting system") designed and mostly written by Donald Knuth and released in 1978.

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Transcendental number

In mathematics, a transcendental number is a real or complex number that is not algebraic—that is, it is not a root of a nonzero polynomial equation with integer (or, equivalently, rational) coefficients.

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Uncial script

Uncial is a majusculeGlaister, Geoffrey Ashall.

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Unicode is a computing industry standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems.

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In continuum mechanics, the vorticity is a pseudovector field that describes the local spinning motion of a continuum near some point (the tendency of something to rotate), as would be seen by an observer located at that point and traveling along with the flow.

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Wind wave

In fluid dynamics, wind waves, or wind-generated waves, are surface waves that occur on the free surface of bodies of water (like oceans, seas, lakes, rivers, canals, puddles or ponds).

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Pi (Greek letter), Pi (Greek), Pi (symbol), Pi letter, Pomega, Variant pi, \pi, Π, Π (letter), Πι, .


[1] https://en.wikipedia.org/wiki/Pi_(letter)

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