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== '''[[Higgs boson]]''' ==
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The '''Higgs boson''' is a massive spin-0 [[elementary particle]] in the [[Standard Model]] of [[particle physics]] that plays a key role in explaining the mass of other elementary particles. The experimental discovery of a particle consistent with the Higgs was announced in a seminar on July 4, 2012.<ref name=Higgs/><ref name=CERN/> This particle was first proposed by Professor [[Peter Higgs]] of [[University of Edinburgh|Edinburgh University]] in 1964 as a means to explain the origin of the masses of the elementary particles by the introduction of an fundamental scalar field. This gives all the fundamental particles mass via a process of spontaneous symmetry breaking called the ''Higgs Mechanism''. The Higgs boson was popularised as the "God particle" by the [[Nobel Prize]]-winning [[physicist]] [[Leon M. Lederman]] in his 1993 popular science book ''The God Particle: If the Universe Is the Answer, What is the Question?'' co-written with science writer Dick Teresi.<ref name=Lederman/><ref name=Fermilab/>
==Footnotes==
 
===The Higgs mechanism===
 
In the [[Standard Model]], the theory that explains experimental observations of [[elementary particle]]s, the [[Quantum chromodynamics|QCD vacuum]] has less symmetry than the force laws governing fundamental interactions. This reduced symmetry situation is not unique, and is found in many systems, among them the ground state of [[ferroelectric]]s and of [[superconductor]]s. In these systems, the greater symmetry of nature is exhibited "on average" by a mosaic of sub-domains individually with reduced symmetry, but statistically exhibiting the greater symmetry of the interactions when all the domains are viewed as an ensemble.
 
In the case of superconductors, the photons, whose exchange mediates the electromagnetic interactions between [[Cooper pairs]], cannot propagate freely because of the presence everywhere of electric charge. In a similar fashion, the Higgs mechanism predicts the symmetry of electroweak interactions is broken by interactions among Higgs bosons in the vacuum, leading (among other things) to non-zero masses for the ''W<sup><big>±</big></sup>'' and ''Z'' weak bosons. In fact, the properties of mass and electric charge stem from interaction with the reduced symmetry vacuum, and are not a result of direct interactions between particles.<ref name=Tully/>
 
''[[Higgs boson|.... (read more)]]''
 
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Latest revision as of 10:19, 11 September 2020

1901 photograph of a stentor (announcer) at the Budapest Telefon Hirmondó.

Telephone newspaper is a general term for the telephone-based news and entertainment services which were introduced beginning in the 1890s, and primarily located in large European cities. These systems were the first example of electronic broadcasting, and offered a wide variety of programming, however, only a relative few were ever established. Although these systems predated the invention of radio, they were supplanted by radio broadcasting stations beginning in the 1920s, primarily because radio signals were able to cover much wider areas with higher quality audio.

History

After the electric telephone was introduced in the mid-1870s, it was mainly used for personal communication. But the idea of distributing entertainment and news appeared soon thereafter, and many early demonstrations included the transmission of musical concerts. In one particularly advanced example, Clément Ader, at the 1881 Paris Electrical Exhibition, prepared a listening room where participants could hear, in stereo, performances from the Paris Grand Opera. Also, in 1888, Edward Bellamy's influential novel Looking Backward: 2000-1887 foresaw the establishment of entertainment transmitted by telephone lines to individual homes.

The scattered demonstrations were eventually followed by the establishment of more organized services, which were generally called Telephone Newspapers, although all of these systems also included entertainment programming. However, the technical capabilities of the time meant that there were limited means for amplifying and transmitting telephone signals over long distances, so listeners had to wear headphones to receive the programs, and service areas were generally limited to a single city. While some of the systems, including the Telefon Hirmondó, built their own one-way transmission lines, others, including the Electrophone, used standard commercial telephone lines, which allowed subscribers to talk to operators in order to select programming. The Telephone Newspapers drew upon a mixture of outside sources for their programs, including local live theaters and church services, whose programs were picked up by special telephone lines, and then retransmitted to the subscribers. Other programs were transmitted directly from the system's own studios. In later years, retransmitted radio programs were added.

During this era telephones were expensive luxury items, so the subscribers tended to be the wealthy elite of society. Financing was normally done by charging fees, including monthly subscriptions for home users, and, in locations such as hotel lobbies, through the use of coin-operated receivers, which provided short periods of listening for a set payment. Some systems also accepted paid advertising.

Footnotes