Simultaneity is the property of two events happening at the same time in at least ONE Reference frame. A property is an intrinsic or extrinsic quality of an object—where an object may be of any differing nature, depending on the context and field — be it computing, philosophy, etc. ... There are many kinds of events. ... 8:17 am, August 6, 1945, Japanese time. ...

• In criminal law, for a criminal violation to be established, it be shown that there was simultaneity of actus reus and mens rea.

• In mathematics, a system of equations or a set of simultaneous equations share variables; a solution is a set of variable values for which all these equations are satisfied simultaneously.

• In music a simultaneity is more than one complete musical texture occurring at the same time, rather than in succession. This first appeared in the music of Charles Ives, and is common in the music of Conlon Nancarrow, and others. A pitch simultaneity is also more than one pitch or pitch class all of which occur at the same time, or simultaneously. Simultaneity is a more general term than chord: most chord progressions or harmonic progressions are then simultaneity successions, though not all simultaneity successions are harmonic progressions and not all simultaneities are chords.

• In modern physics two events may be simultaneous with respect to a time event as follows:

A central event (0,0) is used to anchor a spacetime plane {(x,t) in RxR} = ST where x measures distance in units of 30 centimeters and t measures time in nanoseconds. Space events satisfy |x| > |t| and the time events satisfy |x| < |t|. Now a space event e is simultaneous with the origin (0,0), with respect to a time event z, if e and z are hyperbolic-orthogonal points in ST. Two events g and h in ST are simultaneous with respect to z if their difference g - h in ST is hyperbolic-orthogonal to z. Criminal law (also known as penal law) is the body of law that punishes criminals for committing offences against the state. ... Concurrence or Simultaneity is a legal term, from Western jurisprudence, referring to the simultaneous occurrence of actus reus (bad action) and mens rea (bad mind), which must be present for a crime to have occurred; except in crimes of strict liability. ... Actus reus is the action (or inaction, in the case of criminal negligence and similar crimes which are sometimes called acts of omission) which, in combination with the mens rea (guilty mind), produces criminal liability in common law based criminal law jurisdictions such as the United States, United Kingdom. ... Mens rea is a criminal law concept which focuses on the mental state of the accused and requires proof of a positive state of mind such as intent, recklessness, or willful blindness. ... Wikibooks Wikiversity has more about this subject: School of Mathematics Wikiquote has a collection of quotations by or about: Mathematics Look up Mathematics on Wiktionary, the free dictionary Wikimedia Commons has more media related to: Mathematics Bogomolny, Alexander: Interactive Mathematics Miscellany and Puzzles. ... In mathematics, a set can be thought of as any collection of distinct things considered as a whole. ... In mathematics, simultaneous equations are a set of equations where variables are shared. ... Wikibooks Wikiversity has more about this subject: School of Music Look up Music on Wiktionary, the free dictionary Wikisource, as part of the 1911 Encyclopedia Wikiproject, has original text related to this article: Music Wikicities has a wiki about Music: Music MusicNovatory: the science of music encyclopedia Science of Music... In music, the word texture is often used in a rather vague way in reference to the overall sound of a piece of music. ... Succession is the act or process of following in order or sequence. ... This photo from around 1913 shows Ives in his day job: he was the director of a successful insurance agency. ... Conlon Nancarrow (October 27, 1912 - August 10, 1997) was an American composer who took Mexican citizenship in 1955. ... In music, pitch is the perception of the frequency of a note. ... In music and music theory a pitch class contains all notes that have the same name; for example, all Es, no matter which octave they are in, are in the same pitch class. ... In music and music theory, a chord (from the middle English cord, short for accord) is three or more different notes or pitches sounding simultaneously, or nearly simultaneously, over a period of time. ... A chord progression (also chord sequence and harmonic progression), as its name implies, is a series of chords played in an order. ... Harmony is the use and study of pitch simultaneity and chords, actual or implied, in music. ... In music and music theory a simultaneity succession a series of different groups of pitches or pitch classes, each of which is played at the same as the other pitches of its group. ... In mathematics, two points in the Cartesian plane are hyperbolically orthogonal if the slopes of their rays from the origin are reciprocal to one another. ...

See also

• equation
• relativity of simultaneity
• synchronization
• musical set theory

In mathematics, one often (not quite always) distinguishes between an identity, which is an assertion that two expressions are equal regardless of the values of any variables that occur within them, and an equation, which may be true for only some (or none) of the values of any such variables. ... A simple introduction to this subject is provided in Special relativity for beginners Special relativity (SR) or the special theory of relativity is the physical theory published in 1905 by Albert Einstein. ... Synchronization is coordination with respect to time. ... Musical set theory is a atonal or post-tonal method of musical analysis and composition which is based on explaining and proving musical phenomena, taken as sets and subsets, using mathematical rules and notation and using that information to gain insight to compositions or their creation. ...

External links

• Simultaneity in Music by Robert Iolini. Extract from a Master of Arts thesis entitled Simultaneity in Music. Macquarie University. Sydney. Australia. February 1998.