This is a list of places featured in Douglas Adams's science fiction series, The Hitchhiker's Guide to the Galaxy. The series is set in a fictionalised version of the Milky Way galaxy and thus, while most locations are pure invention, many are based on "real world" settings such as Alpha Centauri, Barnard's Star and various versions of the Earth.
"The Galaxy" is our home galaxy, the Milky Way, though it is referred to exclusively as "the Galaxy" in the series. Apart from a very brief moment during the first radio series, when the main characters were transported outside the galactic plane into a battle with Haggunenons, and a moment when one of Arthur's careless remarks is sent inadvertently through a wormhole into "a distant galaxy", the Galaxy provides the setting for the entire series. It is home to thousands of sentient races, some of whom have achieved interstellar capability, creating a vast network of trade, military and political links. To the technologically advanced inhabitants of the Galaxy, a small, insignificant world such as Earth is considered invariably primitive and backward. The Galaxy appears, at least nominally, to be a single state, with a unified government "run" by an appointed President. Its immensely powerful and monumentally callous civil service is run out of the Megabrantis Cluster, mainly by the Vogons.
SS Arcturus was a passenger ship of the Finland Steamship Company operating primarily on the route between Hanko, Finland and Hull, England via Copenhagen, Denmark. Built in 1898 by Gourlay Brothers shipyard in Dundee, Scotland, the Arcturus remained in service until 1956. In its earlier years it was one of the primary ships that Finnish emigrants sailed on when heading to North America. After disembarking at Hull, such emigrants would typically take a train to Liverpool before boarding a transatlantic liner.
Arcturus is a star.
Arcturus may also refer to:
ARC is a lossless data compression and archival format by System Enhancement Associates (SEA). It was very popular during the early days of networked dial-up BBS. The file format and the program were both called ARC. The ARC program made obsolete the previous use of a combination of the SQ program to compress files and the LU program to create .LBR archives, by combining both compression and archiving functions into a single program. Unlike ZIP, ARC is incapable of compressing entire directory trees. The format was subject to controversy in the 1980s—an important event in debates over what would later be known as open formats.
The .arc file extension is often used for several file archive-like file types. For example, the Internet Archive uses its own ARC format to store multiple web resources into a single file. The FreeArc archiver also uses .arc extension, but uses a completely different file format.
Nintendo uses an unrelated 'ARC' format for resources, such as MIDI, voice samples, or text, in GameCube and Wii games. Several unofficial extractors exist for this type of ARC file.
A (simple) arc in finite projective geometry is a set of points which satisfies, in an intuitive way, a feature of curved figures in continuous geometries. Loosely speaking, they are sets of points that are far from "line-like" in a plane or far from "plane-like" in a three-dimensional space. In this finite setting it is typical to include the number of points in the set in the name, so these simple arcs are called k-arcs. An important generalization of the k-arc concept, also referred to as arcs in the literature, are the (k, d)-arcs.
In a finite projective plane π (not necessarily Desarguesian) a set A of k (k ≥ 3) points such that no three points of A are collinear (on a line) is called a k - arc. If the plane π has order q then k ≤ q + 2, however the maximum value of k can only be achieved if q is even. In a plane of order q, a (q + 1)-arc is called an oval and, if q is even, a (q + 2)-arc is called a hyperoval.
Every conic in the Desarguesian projective plane PG(2,q), i.e., the set of zeros of an irreducible homogeneous quadratic equation, is an oval. A celebrated result of Beniamino Segre states that when q is odd, every (q + 1)-arc in PG(2,q) is a conic. This is one of the pioneering results in finite geometry.
In mathematics, and more specifically in graph theory, a directed graph (or digraph) is a graph, or set of vertices connected by edges, where the edges have a direction associated with them. In formal terms, a directed graph is an ordered pair G = (V, A) (sometimes G = (V, E)) where
It differs from an ordinary or undirected graph, in that the latter is defined in terms of unordered pairs of vertices, which are usually called edges, arcs, or lines.
A directed graph is called a simple digraph if it has no multiple arrows (two or more edges that connect the same two vertices in the same direction) and no loops (edges that connect vertices to themselves). A directed graph is called a directed multigraph or multidigraph if it may have multiple arrows (and sometimes loops). In the latter case the arrow set forms a multiset, rather than a set, of ordered pairs of vertices.