Transactional memoryIn computer science and engineering, transactional memory attempts to simplify concurrent programming by allowing a group of load and store instructions to execute in an atomic way. It is a concurrency control mechanism analogous to database transactions for controlling access to shared memory in concurrent computing. Transactional memory systems provide high-level abstraction as an alternative to low-level thread synchronization. This abstraction allows for coordination between concurrent reads and writes of shared data in parallel systems.
Partition function (number theory)In number theory, the partition function p(n) represents the number of possible partitions of a non-negative integer n. For instance, p(4) = 5 because the integer 4 has the five partitions 1 + 1 + 1 + 1, 1 + 1 + 2, 1 + 3, 2 + 2, and 4. No closed-form expression for the partition function is known, but it has both asymptotic expansions that accurately approximate it and recurrence relations by which it can be calculated exactly. It grows as an exponential function of the square root of its argument.
Rank of a partitionIn mathematics, particularly in the fields of number theory and combinatorics, the rank of a partition of a positive integer is a certain integer associated with the partition. In fact at least two different definitions of rank appear in the literature. The first definition, with which most of this article is concerned, is that the rank of a partition is the number obtained by subtracting the number of parts in the partition from the largest part in the partition.
Quantum mechanics of time travelUntil recently, most studies on time travel are based upon classical general relativity. Coming up with a quantum version of time travel requires physicists to figure out the time evolution equations for density states in the presence of closed timelike curves (CTC). Novikov had conjectured that once quantum mechanics is taken into account, self-consistent solutions always exist for all time machine configurations, and initial conditions. However, it has been noted such solutions are not unique in general, in violation of determinism, unitarity and linearity.
Théorème des nombres pentagonauxEn mathématiques, le théorème des nombres pentagonaux, dû au mathématicien suisse Euler, est le théorème qui établit le développement en série formelle de la fonction d'Euler : Autrement dit : Le nom du théorème vient de la forme des exposants dans le membre droit de l'égalité : ces nombres sont les nombres pentagonaux généralisés. Le théorème des nombres pentagonaux est un cas particulier de l'identité du triple produit de Jacobi. Ce théorème a une interprétation combinatoire en termes de partitions.
Conflit du CachemireLe conflit du Cachemire est lié au différend pour la possession de la région du Cachemire entre l'Inde, les groupes cachemiris, le Pakistan et la Chine. Ce différend a conduit à plusieurs reprises à des affrontements armés entre les trois nations. 220x124px|thumb|right|alt=Un Shenyang F-6,un Lockheed F-104 et un Dassault Mirage-III pakistanais lors de la seconde guerre indo-pakistanaise|Un Shenyang F-6,un Lockheed F-104 et un Dassault Mirage-III pakistanais lors de la seconde guerre indo-pakistanaise Durant l'administration britannique des Indes, le Cachemire est un royaume indépendant dirigé par un maharadja.
