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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== |
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| ===The Higgs mechanism===
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| 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.
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| 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/>
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| ''[[Higgs boson|.... (read more)]]''
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| ! style="text-align: center;" | [[Higgs boson#References|notes]]
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| {{reflist|2}} | | {{reflist|2}} |
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| | </small> |
Latest revision as of 09:19, 11 September 2020
The Mathare Valley slum near Nairobi, Kenya, in 2009.
Poverty is deprivation based on lack of material resources. The concept is value-based and political. Hence its definition, causes and remedies (and the possibility of remedies) are highly contentious.[1] The word poverty may also be used figuratively to indicate a lack, instead of material goods or money, of any kind of quality, as in a poverty of imagination.
Definitions
Primary and secondary poverty
The use of the terms primary and secondary poverty dates back to Seebohm Rowntree, who conducted the second British survey to calculate the extent of poverty. This was carried out in York and was published in 1899. He defined primary poverty as having insufficient income to “obtain the minimum necessaries for the maintenance of merely physical efficiency”. In secondary poverty, the income “would be sufficient for the maintenance of merely physical efficiency were it not that some portion of it is absorbed by some other expenditure.” Even with these rigorous criteria he found that 9.9% of the population was in primary poverty and a further 17.9% in secondary.[2]
Absolute and comparative poverty
More recent definitions tend to use the terms absolute and comparative poverty. Absolute is in line with Rowntree's primary poverty, but comparative poverty is usually expressed in terms of ability to play a part in the society in which a person lives. Comparative poverty will thus vary from one country to another.[3] The difficulty of definition is illustrated by the fact that a recession can actually reduce "poverty".
Causes of poverty
The causes of poverty most often considered are:
- Character defects
- An established “culture of poverty”, with low expectations handed down from one generation to another
- Unemployment
- Irregular employment, and/or low pay
- Position in the life cycle (see below) and household size
- Disability
- Structural inequality, both within countries and between countries. (R H Tawney: “What thoughtful rich people call the problem of poverty, thoughtful poor people call with equal justice a problem of riches”)[4]
As noted above, most of these, or the extent to which they can be, or should be changed, are matters of heated controversy.
- ↑ Alcock, P. Understanding poverty. Macmillan. 1997. ch 1.
- ↑ Harris, B. The origins of the British welfare state. Palgrave Macmillan. 2004. Also, Oxford Dictionary of National Biography.
- ↑ Alcock, Pt II
- ↑ Alcock, Preface to 1st edition and pt III.
