00 (zero) is a number representing an empty quantity. As a number, 0 fulfills a central role in mathematics as the additive identity of the integers, real numbers, and other algebraic structures. In place-value notation such as decimal, 0 also serves as a numerical digit to indicate that that position's power of 10 is not multiplied by anything or added to the resulting number. This concept appears to have been difficult to discover. Common names for the number 0 in English are zero, nought, naught (nɔːt), nil.
Linear mapIn mathematics, and more specifically in linear algebra, a linear map (also called a linear mapping, linear transformation, vector space homomorphism, or in some contexts linear function) is a mapping between two vector spaces that preserves the operations of vector addition and scalar multiplication. The same names and the same definition are also used for the more general case of modules over a ring; see Module homomorphism. If a linear map is a bijection then it is called a .
Special linear Lie algebraIn mathematics, the special linear Lie algebra of order n (denoted or ) is the Lie algebra of matrices with trace zero and with the Lie bracket . This algebra is well studied and understood, and is often used as a model for the study of other Lie algebras. The Lie group that it generates is the special linear group. The Lie algebra is central to the study of special relativity, general relativity and supersymmetry: its fundamental representation is the so-called spinor representation, while its adjoint representation generates the Lorentz group SO(3,1) of special relativity.
Linear algebraic groupIn mathematics, a linear algebraic group is a subgroup of the group of invertible matrices (under matrix multiplication) that is defined by polynomial equations. An example is the orthogonal group, defined by the relation where is the transpose of . Many Lie groups can be viewed as linear algebraic groups over the field of real or complex numbers. (For example, every compact Lie group can be regarded as a linear algebraic group over R (necessarily R-anisotropic and reductive), as can many noncompact groups such as the simple Lie group SL(n,R).
Linear combinationIn mathematics, a linear combination is an expression constructed from a set of terms by multiplying each term by a constant and adding the results (e.g. a linear combination of x and y would be any expression of the form ax + by, where a and b are constants). The concept of linear combinations is central to linear algebra and related fields of mathematics. Most of this article deals with linear combinations in the context of a vector space over a field, with some generalizations given at the end of the article.
Mac OS 8Mac OS 8 is an operating system that was released by Apple Computer on July 26, 1997. It includes the largest overhaul of the classic Mac OS experience since the release of System 7, approximately six years before. It places a greater emphasis on color than prior versions. Released over a series of updates, Mac OS 8 represents an incremental integration of many of the technologies which had been developed from 1988 to 1996 for Apple's overly ambitious OS named Copland.
MacOSmacOS (ˌmækoʊˈɛs; previously OS X and originally Mac OS X) is an operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and laptop computers, it is the second most widely used desktop OS, after Microsoft Windows and ahead of Linux (including ChromeOS). macOS succeeded the classic Mac OS, a Mac operating system with nine releases from 1984 to 1999.
Common EraCommon Era (CE) and Before the Common Era (BCE) are year notations for the Gregorian calendar (and its predecessor, the Julian calendar), the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the original Anno Domini (AD) and Before Christ (BC) notations used for the same calendar era. The two notation systems are numerically equivalent: " CE" and "AD " each describe the current year; "400 BCE" and "400 BC" are the same year.
Mac OS X ServerMac OS X Server is a discontinued series of Unix-like server operating systems developed by Apple Inc. based on macOS. It provided server functionality and system administration tools, and tools to manage both macOS-based computers and iOS-based devices, network services such as a mail transfer agent, AFP and SMB servers, an LDAP server, and a domain name server, as well as server applications including a Web server, database, and calendar server.
Original sin'Original sin' is the Christian doctrine that holds that humans, through the fact of birth, inherit a tainted nature with a proclivity to sinful conduct in need of regeneration. The biblical basis for the belief is generally found in Genesis 3 (the story of the expulsion of Adam and Eve from the Garden of Eden), in a line in Psalm 51:5 ("I was brought forth in iniquity, and in sin did my mother conceive me"), and in Paul's Epistle to the Romans, 5:12-21 ("Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all people, because all sinned").
Calendar eraA calendar era is the period of time elapsed since one epoch of a calendar and, if it exists, before the next one. For example, it is the year as per the Gregorian calendar, which numbers its years in the Western Christian era (the Coptic Orthodox and Ethiopian Orthodox churches have their own Christian eras). In antiquity, regnal years were counted from the accession of a monarch. This makes the chronology of the ancient Near East very difficult to reconstruct, based on disparate and scattered king lists, such as the Sumerian King List and the Babylonian Canon of Kings.
Plasma (physics)Plasma () is one of four fundamental states of matter, characterized by the presence of a significant portion of charged particles in any combination of ions or electrons. It is the most abundant form of ordinary matter in the universe, being mostly associated with stars, including the Sun. Extending to the rarefied intracluster medium and possibly to intergalactic regions, plasma can be artificially generated by heating a neutral gas or subjecting it to a strong electromagnetic field.