{"id":3418,"date":"2026-05-02T20:08:14","date_gmt":"2026-05-02T20:08:14","guid":{"rendered":"https:\/\/www.laspa.slg.br\/?p=3418"},"modified":"2026-05-02T20:08:14","modified_gmt":"2026-05-02T20:08:14","slug":"representando-eletrons","status":"publish","type":"post","link":"https:\/\/www.laspa.slg.br\/en\/2026\/05\/02\/representando-eletrons\/","title":{"rendered":"Representando el\u00e9trons"},"content":{"rendered":"

JENSEN, Pablo. 2005. Making electrons public. In: Bruno Latour; Peter Weibel (eds.). Making things public: atmospheres of democracy<\/em>. Cambridge: The MIT Press\/ZKM, p.334-7.<\/p>\n

A ALMA DO MATERIAL<\/strong><\/p>\n

Adapting what Fran\u00e7ois Philidor, France\u2019s celebrity eighteenth-century chess player, declared (regarding the lowly pawns that, for him, constituted \u201cthe soul of the game of chess\u201d) one could say that electrons are truly the soul of every material. (Jensen 2005:334)<\/p><\/blockquote>\n

COMO REPRESENTAR UM COLETIVO DE EL\u00c9TRONS?<\/strong><\/p>\n

It is therefore essential to reach an accurate representation of the \u201ccollective of electrons\u201d. (Jensen 2005:334)<\/p><\/blockquote>\n

I thought it would be interesting to submit this example for discussion within the framework of the exhibition, since it encapsules the difficulties one encounters when making public the group behavior of entities that are perfectly mastered as individuals. (Jensen 2005:334)<\/p><\/blockquote>\n

How, then, to provide a more detailed representation of the electron population [than the billiard ball model] without at the same time falling back into the chaos of direct expression? (Jensen 2005:335)<\/p><\/blockquote>\n

A PERSONALIDADE TRIDIMENSIONAL DE UM EL\u00c9TRON (carga massa e spin)<\/strong><\/p>\n

The personality of an electron is limited to three characteristics: charge, mass and spin. (Jensen 2005:334)<\/p><\/blockquote>\n

Therefore, the \u201cspeech\u201d of an isolated electron is well-defined, like that of one person speaking clearly. (Jensen 2005:334)<\/p><\/blockquote>\n

FUN\u00c7\u00c3O DE ONDA PARA MAIS DE 1 EL\u00c9TRON<\/strong><\/p>\n

Quantum mechanics obliges us to use a collective \u201cwave function,\u201d which represents the collective of [10] electrons, their individuality being totally lost. (Jensen 2005:334-5)<\/p><\/blockquote>\n

The \u201cimplexity\u201d of the electron-system makes it impossible to represent systems involving more than about 100 electrons in a direct manner. (Jensen 2005:335)<\/p><\/blockquote>\n

A \u201cSOLU\u00c7\u00c3O\u201d DA DENSIDADE<\/strong><\/p>\n

There are two main ideas involved: first, the use of fictitious electrons, electrons freed from gregarious quantum behavior, and second, the introduction of interaction forces that only depend on the electronic density. (Jensen 2005:336)<\/p><\/blockquote>\n

This idea of electrons \u201cfree\u201d from all exterior influence represents an interesting framework, in that while maintaining an operational status, it manages to retain a certain flexibility in the definition of described particles. (Jensen 2005:336)<\/p><\/blockquote>\n

It has been demonstrated that all the properties of electronic systems are \u201chidden\u201d in a simple mathematical quantity, without any quantum complication, namely their density within the material. (Jensen 2005:336)<\/p><\/blockquote>\n

UM REPRESENTANTE REDUNDANTE PARA UM COLETIVO DE EL\u00c9TRONS<\/strong><\/p>\n

In this way, these fictitious electrons accurately reproduce the properties of the group of real electrons. The ideal spokesperson for the electrons has thus been found, one that expresses itself straightforwardly and that is, furthermore, capable of perfectly expressing the will of those it represents. The calculations are still very complex and necessitate the use of large computers, for the fictitious forces depend on the electronic density, which is determined by the position of all the electrons and so is determined by the solution that one is seeking. Physicists have managed to escape this seemingly vicious circle by using a \u201cself-consistent\u201d solution, that is, by repeating the calculation until they converge on a solution for which the calculated forces induce the same density as that which served to produce them.(Jensen 2005:336)<\/p><\/blockquote>\n

HOMO ECONOMICUS<\/em><\/strong><\/p>\n

This spokesperson is, in fact, rather similar to what economists call Homo economicus<\/em>. This fantastical being is a rational individual, virtually independent of other individuals with whom he only enters into relations through the intermediary of the prices of various goods on the market. (Jensen 2005:336-7)<\/p><\/blockquote>\n

Homo economicus<\/em> has finally found a presentable friend in the world of electrons: Electro densiticus<\/em>. In the case of electrons, the simplicity of individuals prevents theoretical sleights of hand from taking place, for the complexities of the real world are not simply brushed under the carpet. Rather, those complexities are perfectly reproduced in the fictitious forces, whereas to represent the interactions between humans solely as a function of market prices is, of course, a gross oversimplification. (Jensen 2005:337)<\/p><\/blockquote>\n

EL\u00c9TRONS=\/=PESSOAS<\/strong><\/p>\n

Physicists have succeeded in finding a good spokesperson for a complex system, one that cannot express itself directly. The trick was to combine a versatile theoretical tool (the independent electrons framework) together with respect for the most important properties of the collective (the density). Of course, there is no direct lesson for human collectivities to be gleaned from this example for at least two reasons. First of all, although electrons\u2019 interactions are complex, the electrons themselves are simple particles. They are, in effect, all identical to one another, whereas each individual human is as complicated as its interactions with others are. Furthermore, as the last example shows, Electro densiticus has become a good spokesperson only at the cost of drastic purifications of the materials used in the experiments. Homo economicus<\/em> has not yet completed his solitary stay in purgatory. (Jensen 2005:337)<\/p>\n","protected":false},"excerpt":{"rendered":"

JENSEN, Pablo. 2005. Making electrons public. In: Bruno Latour; Peter Weibel (eds.). Making things public: atmospheres of democracy. Cambridge: The MIT Press\/ZKM, p.334-7. A ALMA DO MATERIAL Adapting what Fran\u00e7ois Philidor, France\u2019s celebrity eighteenth-century chess player, declared (regarding the lowly pawns that, for him, constituted \u201cthe soul of the game of chess\u201d) one could say that electrons are truly the […]<\/p>\n","protected":false},"author":2,"featured_media":3419,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[7],"tags":[],"class_list":["post-3418","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-fichamento"],"jetpack_featured_media_url":"https:\/\/www.laspa.slg.br\/wp-content\/uploads\/2026\/05\/representando-eletrons-41586_2001_Article_BF35065553_Fig2_HTML.webp","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/posts\/3418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/comments?post=3418"}],"version-history":[{"count":1,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/posts\/3418\/revisions"}],"predecessor-version":[{"id":3420,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/posts\/3418\/revisions\/3420"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/media\/3419"}],"wp:attachment":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/media?parent=3418"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/categories?post=3418"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/tags?post=3418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}