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This is a glossary of some terms used in various branches of mathematics that are related to the fields of order , lattice , and domain theory . Note that there is a structured list of order topics available as well. Other helpful resources might be the following overview articles:
In the following, partial orders wil... | https://en.wikipedia.org/wiki/Projection_(order_theory) |
In set theory , a projection is one of two closely related types of functions or operations, namely:
This set theory -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Projection_(set_theory) |
A projection plane , or plane of projection , is a type of view in which graphical projections from an object intersect. [ 1 ] Projection planes are used often in descriptive geometry and graphical representation. A picture plane in perspective drawing is a type of projection plane.
With perspective drawing, the lines... | https://en.wikipedia.org/wiki/Projection_plane |
In mathematics , a projectionless C*-algebra is a C*-algebra with no nontrivial projections . For a unital C*-algebra, the projections 0 and 1 are trivial. While for a non-unital C*-algebra, only 0 is considered trivial. The problem of whether simple infinite-dimensional C*-algebras with this property exist was posed i... | https://en.wikipedia.org/wiki/Projectionless_C*-algebra |
A projective cone (or just cone ) in projective geometry is the union of all lines that intersect a projective subspace R (the apex of the cone) and an arbitrary subset A (the basis) of some other subspace S , disjoint from R .
In the special case that R is a single point, S is a plane, and A is a conic section on S ,... | https://en.wikipedia.org/wiki/Projective_cone |
In mathematics , projective geometry is the study of geometric properties that are invariant with respect to projective transformations . This means that, compared to elementary Euclidean geometry , projective geometry has a different setting ( projective space ) and a selective set of basic geometric concepts. The bas... | https://en.wikipedia.org/wiki/Projective_geometry |
In mathematics , a projective plane is a geometric structure that extends the concept of a plane . In the ordinary Euclidean plane, two lines typically intersect at a single point, but there are some pairs of lines (namely, parallel lines) that do not intersect. A projective plane can be thought of as an ordinary plane... | https://en.wikipedia.org/wiki/Projective_plane |
In mathematics , the concept of a projective space originated from the visual effect of perspective , where parallel lines seem to meet at infinity . A projective space may thus be viewed as the extension of a Euclidean space , or, more generally, an affine space with points at infinity , in such a way that there is on... | https://en.wikipedia.org/wiki/Projective_space |
In real analysis , the projectively extended real line (also called the one-point compactification of the real line ), is the extension of the set of the real numbers , R {\displaystyle \mathbb {R} } , by a point denoted ∞ . [ 1 ] It is thus the set R ∪ { ∞ } {\displaystyle \mathbb {R} \cup \{\infty \}} with the standa... | https://en.wikipedia.org/wiki/Projectively_extended_real_line |
In mathematics , projectivization is a procedure which associates with a non-zero vector space V a projective space P ( V ) , whose elements are one-dimensional subspaces of V . More generally, any subset S of V closed under scalar multiplication defines a subset of P ( V ) formed by the lines contained in S and is cal... | https://en.wikipedia.org/wiki/Projectivization |
The projector augmented wave method (PAW) is a technique used in ab initio electronic structure calculations. It is a generalization of the pseudopotential and linear augmented-plane-wave methods , and allows for density functional theory calculations to be performed with greater computational efficiency. [ 1 ]
Valenc... | https://en.wikipedia.org/wiki/Projector_augmented_wave_method |
In epigenetics , proline isomerization is the effect that cis-trans isomerization of the amino acid proline has on the regulation of gene expression . Similar to aspartic acid , the amino acid proline has the rare property of being able to occupy both cis and trans isomers of its prolyl peptide bonds with ease. Peptidy... | https://en.wikipedia.org/wiki/Proline_isomerization_in_epigenetics |
Proline organocatalysis is the use of proline as an organocatalyst in organic chemistry . This theme is often considered the starting point for the area of organocatalysis, even though early discoveries went unappreciated. [ 1 ] Modifications, such as MacMillan’s catalyst and Jorgensen's catalysts, proceed with excell... | https://en.wikipedia.org/wiki/Proline_organocatalysis |
Promate is a Taiwanese electronics manufacturing company that develops mainly computing , communications and consumer electronics but also engages in the development, design and manufacturing of computer and mobile accessories. Promate produces personal computer peripherals, MFi certified product, mobile and smartphone... | https://en.wikipedia.org/wiki/Promate |
The Prometheus rocket engine is an ongoing European Space Agency (ESA) development effort begun in 2017 to create a reusable methane -fueled rocket engine for use on the Themis reusable rocket demonstrator and Ariane Next , the successor to Ariane 6 , and possibly a version of Ariane 6 itself. [ 1 ] [ 2 ]
Prometheus i... | https://en.wikipedia.org/wiki/Prometheus_(rocket_engine) |
Promicromonosporaceae is an Actinomycete family. [ 1 ] [ 2 ]
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature [ 2 ] and the phylogeny is based on whole-genome sequences. [ 3 ] [ a ]
Luteimicrobium
Promicromonospora
Xylanimonas
Krasilnikoviella
Isoptericola
P... | https://en.wikipedia.org/wiki/Promicromonosporaceae |
Promiscuous gene expression (PGE), formerly referred to as ectopic expression, is a process specific to the thymus that plays a pivotal role in the establishment of central tolerance . This phenomenon enables generation of self- antigens , so called tissue-restricted antigens (TRAs), which are in the body expressed onl... | https://en.wikipedia.org/wiki/Promiscuous_gene_expression |
In genetics , a promoter is a sequence of DNA to which proteins bind to initiate transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein ( mRNA ), or can have a function in and of itself, such as tRNA or rRNA . Promoters are located near the transcriptio... | https://en.wikipedia.org/wiki/Promoter_(genetics) |
Promoter activity is a term that encompasses several meanings around the process of gene expression from regulatory sequences — promoters [ 2 ] and enhancers . [ 3 ] Gene expression has been commonly characterized as a measure of how much, how fast, when and where this process happens. [ 4 ] Promoters and enhancers are... | https://en.wikipedia.org/wiki/Promoter_activity |
Promoter bashing is a technique used in molecular biology to identify how certain regions of a DNA strand , commonly promoters , affect the transcription of downstream genes. Under normal circumstances, proteins bind to the promoter and activate or repress transcription. In a promoter bashing assay , specific point mut... | https://en.wikipedia.org/wiki/Promoter_bashing |
The Promoting Women in Entrepreneurship Act ( Pub. L. 115–6 (text) (PDF) , H.R. 255 ) is a public law amendment to the Science and Engineering Equal Opportunities Act ( Pub. L. 96–516 ) to authorize the National Science Foundation to encourage its entrepreneurial programs to recruit and support women to extend their fo... | https://en.wikipedia.org/wiki/Promoting_Women_in_Entrepreneurship_Act |
In nuclear engineering , prompt criticality describes a nuclear fission event in which criticality (the threshold for an exponentially growing nuclear fission chain reaction) is achieved with prompt neutrons alone and does not rely on delayed neutrons . As a result, prompt supercriticality causes a much more rapid gro... | https://en.wikipedia.org/wiki/Prompt_criticality |
Prompt-gamma neutron activation analysis ( PGAA ) is a very widely applicable technique for determining the presence and amount of many elements simultaneously in samples ranging in size from micrograms to many grams. It is a non-destructive method, and the chemical form and shape of the sample are relatively unimporta... | https://en.wikipedia.org/wiki/Prompt_gamma_neutron_activation_analysis |
Prone position ( / p r oʊ n / ) is a body position in which the person lies flat with the chest down and the back up. In anatomical terms of location , the dorsal side is up, and the ventral side is down. The supine position is the 180° contrast.
The word prone , meaning "naturally inclined to something, apt, liable,"... | https://en.wikipedia.org/wiki/Prone_position |
Pronova BioPharma is a Norwegian company. In Denmark it is a bulk manufacturer of omega-3 products with a manufacturing plant in Kalundborg . It was acquired by BASF in 2014. [ 1 ]
Pronova BioPharma ASA had its roots in Norway's codfish liver oil industry. The company was founded in 1991 as a spinout from the JC Marte... | https://en.wikipedia.org/wiki/Pronova_BioPharma |
A pronucleus ( pl. : pronuclei ) denotes the nucleus found in either a sperm or egg cell during the process of fertilization . The sperm cell undergoes a transformation into a pronucleus after entering the egg cell but prior to the fusion of the genetic material of both the sperm and egg. In contrast, the egg cell poss... | https://en.wikipedia.org/wiki/Pronucleus |
Proof-carrying code ( PCC ) is a software mechanism that allows a host system to verify properties about an application via a formal proof that accompanies the application's executable code. The host system can quickly verify the validity of the proof, and it can compare the conclusions of the proof to its own securit... | https://en.wikipedia.org/wiki/Proof-carrying_code |
Proof-theoretic semantics is an approach to the semantics of logic that attempts to locate the meaning of propositions and logical connectives not in terms of interpretations , as in Tarskian approaches to semantics, but in the role that the proposition or logical connective plays within a system of inference .
Gerhar... | https://en.wikipedia.org/wiki/Proof-theoretic_semantics |
A proof is sufficient evidence or a sufficient argument for the truth of a proposition . [ 1 ] [ 2 ] [ 3 ] [ 4 ]
The concept applies in a variety of disciplines, [ 5 ] with both the nature of the evidence or justification and the criteria for sufficiency being area-dependent. In the area of oral and written communicat... | https://en.wikipedia.org/wiki/Proof_(truth) |
In computer science and mathematical logic , a proof assistant or interactive theorem prover is a software tool to assist with the development of formal proofs by human–machine collaboration. This involves some sort of interactive proof editor, or other interface , with which a human can guide the search for proofs, th... | https://en.wikipedia.org/wiki/Proof_assistant |
In logic , proof by contradiction is a form of proof that establishes the truth or the validity of a proposition by showing that assuming the proposition to be false leads to a contradiction .
Although it is quite freely used in mathematical proofs, not every school of mathematical thought accepts this kind of nonconst... | https://en.wikipedia.org/wiki/Proof_by_contradiction |
In mathematics , a proof by infinite descent , also known as Fermat's method of descent, is a particular kind of proof by contradiction [ 1 ] used to show that a statement cannot possibly hold for any number, by showing that if the statement were to hold for a number, then the same would be true for a smaller number, l... | https://en.wikipedia.org/wiki/Proof_by_infinite_descent |
Proof by intimidation (or argumentum verbosum ) is a humorous phrase used mainly in mathematics to refer to a specific form of hand-waving whereby one attempts to advance an argument by giving an argument loaded with jargon and obscure results or by marking it as obvious or trivial . [ 1 ] It attempts to intimidate the... | https://en.wikipedia.org/wiki/Proof_by_intimidation |
In mathematical logic , a proof calculus or a proof system is built to prove statements .
A proof system includes the components: [ 1 ] [ 2 ]
A formal proof of a well-formed formula in a proof system is a set of axioms and rules of inference of proof system that infers that the well-formed formula is a theorem of pr... | https://en.wikipedia.org/wiki/Proof_calculus |
In proof theory , an area of mathematical logic , proof compression is the problem of algorithmically compressing formal proofs . The developed algorithms can be used to improve the proofs generated by automated theorem proving tools such as SAT solvers , SMT-solvers , first-order theorem provers and proof assistants .... | https://en.wikipedia.org/wiki/Proof_compression |
In proof theory , a branch of mathematical logic , proof mining (or proof unwinding ) is a research program that studies or analyzes formalized proofs, especially in analysis , to obtain explicit bounds, ranges or rates of convergence from proofs that, when expressed in natural language, appear to be nonconstructive . ... | https://en.wikipedia.org/wiki/Proof_mining |
In proof theory , proof nets are a geometrical method of representing proofs that
eliminates two forms of bureaucracy that differentiate proofs: (A) irrelevant syntactical features of regular proof calculi, and (B) the order of rules applied in a derivation. In this way, the formal properties of proof identity corresp... | https://en.wikipedia.org/wiki/Proof_net |
In mathematics , Bertrand's postulate (now a theorem ) states that, for each n ≥ 2 {\displaystyle n\geq 2} , there is a prime p {\displaystyle p} such that n < p < 2 n {\displaystyle n<p<2n} . First conjectured in 1845 by Joseph Bertrand , [ 1 ] it was first proven by Chebyshev , and a shorter but also advanced proof w... | https://en.wikipedia.org/wiki/Proof_of_Bertrand's_postulate |
Fermat's Last Theorem is a theorem in number theory , originally stated by Pierre de Fermat in 1637 and proven by Andrew Wiles in 1995. The statement of the theorem involves an integer exponent n larger than 2. In the centuries following the initial statement of the result and before its general proof, various proofs... | https://en.wikipedia.org/wiki/Proof_of_Fermat's_Last_Theorem_for_specific_exponents |
In mathematics , an impossibility theorem is a theorem that demonstrates a problem or general set of problems cannot be solved. These are also known as proofs of impossibility , negative proofs , or negative results . Impossibility theorems often resolve decades or centuries of work spent looking for a solution by prov... | https://en.wikipedia.org/wiki/Proof_of_impossibility |
Leonhard Euler proved the Euler product formula for the Riemann zeta function in his thesis Variae observationes circa series infinitas ( Various Observations about Infinite Series ), published by St Petersburg Academy in 1737. [ 1 ] [ 2 ]
The Euler product formula for the Riemann zeta function reads
where the left h... | https://en.wikipedia.org/wiki/Proof_of_the_Euler_product_formula_for_the_Riemann_zeta_function |
In logic , and in particular proof theory , a proof procedure for a given logic is a systematic method for producing proofs in some proof calculus of (provable) statements.
There are several types of proof calculi. The most popular are natural deduction , sequent calculi (i.e., Gentzen -type systems), Hilbert systems ... | https://en.wikipedia.org/wiki/Proof_procedure |
This article gives a sketch of a proof of Gödel's first incompleteness theorem . This theorem applies to any formal theory that satisfies certain technical hypotheses, which are discussed as needed during the sketch. We will assume for the remainder of the article that a fixed theory satisfying these hypotheses has bee... | https://en.wikipedia.org/wiki/Proof_sketch_for_Gödel's_first_incompleteness_theorem |
Proofs of the mathematical result that the rational number 22 / 7 is greater than π (pi) date back to antiquity. One of these proofs, more recently developed but requiring only elementary techniques from calculus, has attracted attention in modern mathematics due to its mathematical elegance and its connections to ... | https://en.wikipedia.org/wiki/Proof_that_22/7_exceeds_π |
The number e was introduced by Jacob Bernoulli in 1683. More than half a century later, Euler , who had been a student of Jacob's younger brother Johann , proved that e is irrational ; that is, that it cannot be expressed as the quotient of two integers.
Euler wrote the first proof of the fact that e is irrational in ... | https://en.wikipedia.org/wiki/Proof_that_e_is_irrational |
In the 1760s, Johann Heinrich Lambert was the first to prove that the number π is irrational , meaning it cannot be expressed as a fraction a / b {\displaystyle a/b} , where a {\displaystyle a} and b {\displaystyle b} are both integers . In the 19th century, Charles Hermite found a proof that requires no prerequisite k... | https://en.wikipedia.org/wiki/Proof_that_π_is_irrational |
In mathematics , a proof without words (or visual proof ) is an illustration of an identity or mathematical statement which can be demonstrated as self-evident by a diagram without any accompanying explanatory text. Such proofs can be considered more elegant than formal or mathematically rigorous proofs due to their se... | https://en.wikipedia.org/wiki/Proof_without_words |
The term proofreading is used in genetics to refer to the error-correcting processes, first proposed by John Hopfield [ 1 ] and Jacques Ninio , [ 2 ] involved in DNA replication , immune system specificity, and enzyme-substrate recognition among many other processes that require enhanced specificity. The kinetic proofr... | https://en.wikipedia.org/wiki/Proofreading_(biology) |
Proofs That Really Count: the Art of Combinatorial Proof is an undergraduate-level mathematics book on combinatorial proofs of mathematical identies . That is, it concerns equations between two integer -valued formulas, shown to be equal either by showing that both sides of the equation count the same type of mathemati... | https://en.wikipedia.org/wiki/Proofs_That_Really_Count |
Proofs from THE BOOK is a book of mathematical proofs by Martin Aigner and Günter M. Ziegler . The book is dedicated to the mathematician Paul Erdős , who often referred to "The Book" in which God keeps the most elegant proof of each mathematical theorem . During a lecture in 1985, Erdős said, "You don't have to believ... | https://en.wikipedia.org/wiki/Proofs_from_THE_BOOK |
This article contains mathematical proofs for some properties of addition of the natural numbers : the additive identity, commutativity, and associativity. These proofs are used in the article Addition of natural numbers .
This article will use the Peano axioms for the definition of natural numbers. With these axioms,... | https://en.wikipedia.org/wiki/Proofs_involving_the_addition_of_natural_numbers |
This article collects together a variety of proofs of Fermat's little theorem , which states that
for every prime number p and every integer a (see modular arithmetic ).
Some of the proofs of Fermat's little theorem given below depend on two simplifications.
The first is that we may assume that a is in the range 0 ≤... | https://en.wikipedia.org/wiki/Proofs_of_Fermat's_little_theorem |
This article is supplemental for “ Convergence of random variables ” and provides proofs for selected results.
Several results will be established using the portmanteau lemma : A sequence { X n } converges in distribution to X if and only if any of the following conditions are met:
Proof: If { X n } {\displaystyle \{... | https://en.wikipedia.org/wiki/Proofs_of_convergence_of_random_variables |
In number theory , the law of quadratic reciprocity , like the Pythagorean theorem , has lent itself to an unusually large number of proofs . Several hundred proofs of the law of quadratic reciprocity have been published.
Of the elementary combinatorial proofs, there are two which apply types of double counting . One ... | https://en.wikipedia.org/wiki/Proofs_of_quadratic_reciprocity |
The following are proofs of several characteristics related to the chi-squared distribution .
Let random variable Y be defined as Y = X 2 where X has normal distribution with mean 0 and variance 1 (that is X ~ N (0,1)).
Then, for y < 0 , F Y ( y ) = P ( Y < y ) = 0 and for y ≥ 0 , F Y ( y ) = P ( Y < y ) = P ( X 2 < ... | https://en.wikipedia.org/wiki/Proofs_related_to_chi-squared_distribution |
The propagation constant of a sinusoidal electromagnetic wave is a measure of the change undergone by the amplitude and phase of the wave as it propagates in a given direction. The quantity being measured can be the voltage , the current in a circuit , or a field vector such as electric field strength or flux density .... | https://en.wikipedia.org/wiki/Propagation_constant |
In database systems, a propagation constraint "details what should happen to a related table when we update a row or rows of a target table" (Paul Beynon-Davies, 2004, p.108). Tables are linked using primary key to foreign key relationships. It is possible for users to update one table in a relationship in such a way t... | https://en.wikipedia.org/wiki/Propagation_constraint |
In quantum mechanics and quantum field theory , the propagator is a function that specifies the probability amplitude for a particle to travel from one place to another in a given period of time, or to travel with a certain energy and momentum. In Feynman diagrams , which serve to calculate the rate of collisions in qu... | https://en.wikipedia.org/wiki/Propagator |
Propane ( / ˈ p r oʊ p eɪ n / ) is a three- carbon alkane with the molecular formula C 3 H 8 . It is a gas at standard temperature and pressure , but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is often a constituent of liquefied petroleum gas (LPG), which i... | https://en.wikipedia.org/wiki/Propane |
1,3-Propanedithiol is the chemical compound with the formula HSCH 2 CH 2 CH 2 SH. This di thiol is a useful reagent in organic synthesis . This liquid, which is readily available commercially, has an intense stench.
1,3-Propanedithiol has been used for the protection of aldehydes and ketones via their reversible for... | https://en.wikipedia.org/wiki/Propane-1,3-dithiol |
This page provides supplementary chemical data on propane .
Propane is highly temperature dependent. [ 3 ] The density of liquid and gaseous propane are given on the next image.
Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.
Propane does not have health effects other than the danger of frost... | https://en.wikipedia.org/wiki/Propane_(data_page) |
Propane refrigeration is a type of compression refrigeration . Propane (R290) has been used successfully in industrial refrigeration for many years, and is emerging as an increasingly viable alternative for homes and businesses. Propane's operating pressures and temperatures are well suited for use in air conditioning ... | https://en.wikipedia.org/wiki/Propane_refrigeration |
Propanephosphonic acid anhydride ( PPAA , T3P ) is an anhydride of propane phosphonic acid . Its structure is a cyclic trimer , with a phosphorus–oxygen core and propyl groups and additional oxygens attached. [ 1 ] The chemical is a useful reagent for peptide synthesis reactions, where it activates the carboxylic acid ... | https://en.wikipedia.org/wiki/Propanephosphonic_acid_anhydride |
In organic chemistry , the propargyl group is a functional group of 2- propynyl with the structure CH≡C−CH 2 − . It is an alkyl group derived from propyne ( HC≡C−CH 3 ).
The term propargylic refers to a saturated position ( sp 3 -hybridized ) on a molecular framework next to an alkynyl group. The name comes from mix o... | https://en.wikipedia.org/wiki/Propargyl_group |
A propellant (or propellent ) is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion , and "propel" a vehicle, projectile , or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine . Altho... | https://en.wikipedia.org/wiki/Propellant |
The propensity theory of probability is a probability interpretation in which the probability is thought of as a physical propensity, disposition, or tendency of a given type of situation to yield an outcome of a certain kind, or to yield a long-run relative frequency of such an outcome. [ 1 ]
Propensities are not rel... | https://en.wikipedia.org/wiki/Propensity_probability |
In organic chemistry , 1-propenyl (or simply propenyl ) has the formula CH=CHCH 3 and 2-propenyl ( isopropenyl ) has the formula CH 2 =C-CH 3 . These groups are found in many compounds. Propenyl compounds are isomeric with allyl compounds, which have the formula CH 2 -CH=CH 2 .
Many phenylpropanoids and their derivati... | https://en.wikipedia.org/wiki/Propenyl |
Proper length [ 1 ] or rest length [ 2 ] is the length of an object in the object's rest frame .
The measurement of lengths is more complicated in the theory of relativity than in classical mechanics . In classical mechanics, lengths are measured based on the assumption that the locations of all points involved are m... | https://en.wikipedia.org/wiki/Proper_length |
Proper motion is the astrometric measure of changes in the apparent places of stars or other celestial objects as they move relative to the center of mass of the Solar System . It is measured relative to the distant stars or a stable reference such as the International Celestial Reference Frame (ICRF). [ 1 ] Patterns i... | https://en.wikipedia.org/wiki/Proper_motion |
Proper right and proper left are conceptual terms used to unambiguously convey relative direction when describing an image or other object. The "proper right" hand of a figure is the hand that would be regarded by that figure as its right hand. [ 1 ] In a frontal representation, that appears on the left as the viewer s... | https://en.wikipedia.org/wiki/Proper_right_and_proper_left |
In relativity , proper time (from Latin, meaning own time ) along a timelike world line is defined as the time as measured by a clock following that line. The proper time interval between two events on a world line is the change in proper time, which is independent of coordinates, and is a Lorentz scalar . [ 1 ] The in... | https://en.wikipedia.org/wiki/Proper_time |
The chemical elements can be broadly divided into metals , metalloids , and nonmetals according to their shared physical and chemical properties . All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and hav... | https://en.wikipedia.org/wiki/Properties_of_metals,_metalloids_and_nonmetals |
Nonmetals show more variability in their properties than do metals. [ 1 ] Metalloids are included here since they behave predominately as chemically weak nonmetals.
Physically, they nearly all exist as diatomic or monatomic gases, or polyatomic solids having more substantial (open-packed) forms and relatively small at... | https://en.wikipedia.org/wiki/Properties_of_nonmetals_(and_metalloids)_by_group |
Water ( H 2 O ) is a polar inorganic compound that is at room temperature a tasteless and odorless liquid , which is nearly colorless apart from an inherent hint of blue . It is by far the most studied chemical compound [ 20 ] and is described as the "universal solvent " [ 21 ] and the "solvent of life". [ 22 ] It is t... | https://en.wikipedia.org/wiki/Properties_of_water |
In mathematics , a property is any characteristic that applies to a given set . [ 1 ] Rigorously , a property p defined for all elements of a set X is usually defined as a function p : X → {true, false}, that is true whenever the property holds; or, equivalently, as the subset of X for which p holds; i.e. the set { x ... | https://en.wikipedia.org/wiki/Property_(mathematics) |
In geometric topology , the Property P conjecture is a statement about 3-manifolds obtained by Dehn surgery on a knot in the 3-sphere . A knot in the 3-sphere is said to have Property P if every 3-manifold obtained by performing (non-trivial) Dehn surgery on the knot is not simply-connected . [ 1 ] The conjecture state... | https://en.wikipedia.org/wiki/Property_P_conjecture |
Property maintenance relates to the upkeep of a home , apartment , rental property or building and may be a commercial venture through a property maintenance company, an employee of the company which owns a home, apartment or a self-storage pastime for example day-to-day housekeeping or cleaning. [ 1 ] [ 2 ]
This econ... | https://en.wikipedia.org/wiki/Property_maintenance |
Prophase (from Ancient Greek προ- ( pro- ) ' before ' and φάσις (phásis) ' appearance ' ) is the first stage of cell division in both mitosis and meiosis . Beginning after interphase , DNA has already been replicated when the cell enters prophase. The main occurrences in prophase are the condensation of the chromatin r... | https://en.wikipedia.org/wiki/Prophase |
Propidium iodide (or PI ) is a fluorescent intercalating agent that can be used to stain cells and nucleic acids . PI binds to DNA by intercalating between the bases with little or no sequence preference. When in an aqueous solution, PI has a fluorescent excitation maximum of 493 nm (blue-green), and an emission maximu... | https://en.wikipedia.org/wiki/Propidium_iodide |
Propidium monoazide ( PMA ) is a photoreactive DNA-binding dye that preferentially binds to dsDNA . It is used to detect viable microorganisms by qPCR . [ 1 ] Visible light (high power halogen lamps or specific LED devices [ 2 ] ) induces a photoreaction of the chemical that will lead to a covalent bond with PMA and th... | https://en.wikipedia.org/wiki/Propidium_monoazide |
Propionyl-CoA is a coenzyme A derivative of propionic acid . It is composed of a 24 total carbon chain (without the coenzyme, it is a 3 carbon structure) and its production and metabolic fate depend on which organism it is present in. [ 1 ] Several different pathways can lead to its production, such as through the cata... | https://en.wikipedia.org/wiki/Propionyl-CoA |
Propionyl chloride (also propanoyl chloride ) is the organic compound with the formula CH 3 CH 2 C(O)Cl. It is the acyl chloride derivative of propionic acid . It undergoes the characteristic reactions of acyl chlorides. [ 1 ] It is a colorless, corrosive, volatile liquid .
It is used as a reagent for organic synthes... | https://en.wikipedia.org/wiki/Propionyl_chloride |
A proportion is a mathematical statement expressing equality of two ratios . [ 1 ] [ 2 ]
a : b = c : d {\displaystyle a:b=c:d}
a and d are called extremes , b and c are called means .
Proportion can be written as a b = c d {\displaystyle {\frac {a}{b}}={\frac {c}{d}}} , where ratios are expressed as fractions .
Suc... | https://en.wikipedia.org/wiki/Proportion_(mathematics) |
Proportional-fair scheduling is a compromise-based scheduling algorithm . It is based upon maintaining a balance between two competing interests: Trying to maximize the total throughput of the network (wired or not) while at the same time allowing all users at least a minimal level of service. This is done by assigning... | https://en.wikipedia.org/wiki/Proportional-fair_scheduling |
Proportional control , in engineering and process control, is a type of linear feedback control system in which a correction is applied to the controlled variable, and the size of the correction is proportional to the difference between the desired value ( setpoint , SP) and the measured value ( process variable , PV)... | https://en.wikipedia.org/wiki/Proportional_control |
Reasoning based on relations of proportionality is one form of what in Piaget's theory of cognitive development is called "formal operational reasoning", which is acquired in the later stages of intellectual development. There are methods by which teachers can guide students in the correct application of proportional r... | https://en.wikipedia.org/wiki/Proportional_reasoning |
In mathematics , two sequences of numbers, often experimental data , are proportional or directly proportional if their corresponding elements have a constant ratio . The ratio is called coefficient of proportionality (or proportionality constant ) and its reciprocal is known as constant of normalization (or normalizin... | https://en.wikipedia.org/wiki/Proportionality_(mathematics) |
A proportional–integral–derivative controller ( PID controller or three-term controller ) is a feedback -based control loop mechanism commonly used to manage machines and processes that require continuous control and automatic adjustment. It is typically used in industrial control systems and various other applications... | https://en.wikipedia.org/wiki/Proportional–integral–derivative_controller |
The proportionator is the most efficient unbiased stereological method used to estimate population size in samples.
A typical application is counting the number of cells in an organ . The proportionator is related to the optical fractionator and physical dissector methods that also estimate population. The optical and... | https://en.wikipedia.org/wiki/Proportionator |
A proposition is a central concept in the philosophy of language , semantics , logic , and related fields, often characterized as the primary bearer of truth or falsity . Propositions are also often characterized as the type of object that declarative sentences denote . For instance, the sentence "The sky is blue" deno... | https://en.wikipedia.org/wiki/Proposition |
In propositional logic , a propositional formula is a type of syntactic formula which is well formed . If the values of all variables in a propositional formula are given, it determines a unique truth value . A propositional formula may also be called a propositional expression , a sentence , [ 1 ] or a sentential form... | https://en.wikipedia.org/wiki/Propositional_formula |
In propositional calculus , a propositional function or a predicate is a sentence expressed in a way that would assume the value of true or false , except that within the sentence there is a variable ( x ) that is not defined or specified (thus being a free variable ), which leaves the statement undetermined. The sente... | https://en.wikipedia.org/wiki/Propositional_function |
In propositional calculus and proof complexity a propositional proof system ( pps ), also called a Cook–Reckhow propositional proof system , is a system for proving classical propositional tautologies.
Formally a pps is a polynomial-time function P whose range is the set of all propositional tautologies (denoted TAUT)... | https://en.wikipedia.org/wiki/Propositional_proof_system |
Proprietary firmware is any firmware that has had its use, private modification, copying , or republishing restricted by the producer. Proprietors may enforce restrictions by technical means, such as by restricting source code access, firmware replacement restrictions (by denying complete tooling that may be necessary ... | https://en.wikipedia.org/wiki/Proprietary_firmware |
In telecommunications , a proprietary protocol is a communications protocol owned by a single organization or individual. [ 1 ]
Ownership by a single organization gives the owner the ability to place restrictions on the use of the protocol and to change the protocol unilaterally. Specifications for proprietary protoco... | https://en.wikipedia.org/wiki/Proprietary_protocol |
Propylene glycol dinitrate ( PGDN , 1,2-propylene glycol dinitrate , or 1,2-propanediol dinitrate ) is an organic chemical , an ester of nitric acid and propylene glycol . It is structurally similar to nitroglycerin , except that it has one fewer nitrate group. It is a characteristically and unpleasantly smelling [ 4 ]... | https://en.wikipedia.org/wiki/Propylene_glycol_dinitrate |
In organic chemistry , a propynyl group is a propyl bearing a triple bond. [ 1 ]
This organic chemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Propynyl_group |
Propynylidyne is a chemical compound that has been identified in interstellar space .
μ D =3.551 Debye [ 1 ]
2 Π electronic ground state
A rotational spectrum of the 2 Π electronic ground state of l -C 3 H can be made using the PGopher software (a Program for Simulating Rotational Structure, C. M. Western, Universit... | https://en.wikipedia.org/wiki/Propynylidyne |
A prosection is the dissection of a cadaver (human or animal) or part of a cadaver by an experienced anatomist in order to demonstrate for students anatomic structure . [ 1 ] In a dissection , students learn by doing; in a prosection, students learn by either observing a dissection being performed by an experienced ana... | https://en.wikipedia.org/wiki/Prosection |
In mathematics , the trigonometric functions (also called circular functions , angle functions or goniometric functions ) [ 1 ] are real functions which relate an angle of a right-angled triangle to ratios of two side lengths. They are widely used in all sciences that are related to geometry , such as navigation , soli... | https://en.wikipedia.org/wiki/Prosinus |
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