In physics, a coincidence circuit is an electronic device with one output and two (or more) inputs. The output is activated only when signals are received at the same time at both (or all) inputs. A coincidence circuit was produced in 1924 by Walther Bothe to detect cosmic ray events, and other atomic and sub-atomic particles. The technique later influenced several fields of technology, including the design of RADAR circuits in the 1940s. Since antiquity, people have tried to understand the behavior of matter: why unsupported objects drop to the ground, why different materials have different properties, and so forth. ... 1924 (MCMXXIV) was a leap year starting on Tuesday (link will take you to calendar). ... Walther Wilhelm Georg Bothe (January 8, 1891 – February 8, 1957) was a German physicist, mathematician, chemist, and Nobel Prize winner. ... Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ... This long range radar antenna (approximately 40m (130ft) in diameter) rotates on a track to observe activities near the horizon. ... // Events and trends The 1940s were seen as a transition period between the radical 1930s and the conservative 1950s, which also leads the period to be divided in two halves: The first half of the decade was dominated by World War II, the widest and most destructive armed conflict in...

The main idea of coincidence detection is that if a detector detects some particle ("clicks" in the jargon) this is possibly (with a certain probability, p) not a real event but thermal or other noise. But if two detectors click simultaneously, the probability that it is still a noise event (or a "dark count", as quantum optics people call it) is extremely reduced -- the probability is now p². Hence use of a coincidence circuit greatly improves signal-to-noise ratio. In general, something that reacts to stimuli in a set manner, and is either part of a living being, or made by a living being, for the purpose of doing such reacting. ... A particle is Look up Particle in Wiktionary, the free dictionary In particle physics, a basic unit of matter or energy. ... Jargon is a type of terminology which is used in conjunction with a specific activity, e. ... This article is about the atmospheric phenomenon. ... In science, and especially in physics and telecommunication, noise is fluctuations in and the addition of external factors to the stream of target information (signal) being received at a detector. ... Quantum optics is a field of research in physics, dealing with the application of quantum mechanics to phenomena involving light and its interactions with matter. ... Signal-to-noise ratio (often abbreviated SNR or S/N) is meaningful both in the context of information theory and, informally, for Usenet or other newsgroup-like services. ...

The coincidence circuit needs to have a suitable "coincidence window", i.e. must be able to differentiate between two signals which come at the same time from those which have too much (e.g. more than a few microseconds) temporal distance. Designing such electronics was a major achievement at Bothe's time and earned him the 1954 Nobel Prize in physics, which he shared with Max Born. A microsecond is an SI unit of time equal to one millionth (10-6) of a second. ... 1954 (MCMLIV) was a common year starting on Friday of the Gregorian calendar. ... Hannes Alfvén, 1970 winner for work on astrophysical plasmas List of Nobel Prize laureates in Physics from 1901 to the present day. ... Max Born Max Born (born December 11, 1882 in Breslau, died January 5, 1970 in Göttingen) was a German mathematician and physicist of Jewish heritage. ...

Despite Bothe's Nobel Prize and the resulting perception that he was responsible for the original discovery, Nikola Tesla's legal priority in the matter can be traced 30 years earlier to several lectures, a remote controlled submarine teleautomaton built in 1899 and registered US#613,809, and a patent US#725,605 for a private system of signaling. Both devices were intended to be "non-interfering and non-interferable", and so they encorporated a receiver responsive only when several frequencies are combined in the correct order and duration in the "AND" circuit, thus allowing for greatly increased capacity of transmission lines and privacy of messages. Those were the first electronic AND logic gates introduced to the art, and have since become one of the building blocks of modern computers. Nikola Tesla (July 10, 1856 – c. ... // Headline text A logic gate is an arrangement of controlled switches used to calculate operations using Boolean algebra in digital circuits. ...