37,995 research outputs found
The hysterical anorexia epidemic in the French nineteenth-century
The official birth of hysterical anorexia is attributed to the French alienist Ernest Charles LasĂšgue (1816-1883). Starting from his 1873 article, anorexia as a ânewâ psychopathological picture is subjected to extensive clinical and theoreticalstudy. This paper is not an analysis about the process through which anorexia was formalized as specific psychiatric condition. Rather, it focuses on another important issue: the possibility that the âsameâ disorder may have different meaning depending on the historical period considered. Furthermore, it is asserted that the study of every pathological form is conditioned by social, individual and cultural conditions. For example, in the same year the English Sir William Gull publishes a paper about âanorexia nervosaâ which is described in a different way depending on the different perspective. LasĂšgueâs description is a way of seeing a kind of sufferance, that is he âseesâ this pathology through the hysterical paradigm. Starting from these considerations, this article discusses the construct of âhysterical anorexiaâ trying to understand why, in late nineteenth century France, hysteria and anorexia were viewed as two aspects of the same specific disorder. Finally, it is discussed why anorexia gradually emerged as an independent mental disorder just after the death of Charcot (1893)
The Dirac equation, the concept of quanta, and the description of interactions in quantum electrodynamics
In this article the Dirac equation is used as a guideline to the historical emergence of the concept of quanta, associated with the quantum field. In Pascual Jordanâs approach, electrons as quanta result from the quantization of a classical field described by the Dirac equation. With this quantization procedure â also used for the electromagnetic field â the concept of quanta becomes a central piece in quantum electrodynamics. This does not seem to avoid the apparent impossibility of using the concept of quanta when interacting fields are considered together as a closed system. In this article it is defended that the type of analysis that leads to so drastic conclusions is avoidable if we look beyond the mathematical structure of the theory and take into account the physical ideas inscribed in this mathematical structure. In this case we see that in quantum electrodynamics we are not considering a closed system of interacting fields, what we have is a description of the interactions between distinct fields. In this situation the concept of quanta is central, the Fock space being the natural mathematical structure that permits maintaining the concept of quanta when considering the interaction between the fields
Time in the theory of relativity: on natural clocks, proper time, the clock hypothesis, and all that
When addressing the notion of proper time in the theory of relativity, it is
usually taken for granted that the time read by an accelerated clock is given
by the Minkowski proper time. However, there are authors like Harvey Brown that
consider necessary an extra assumption to arrive at this result, the so-called
clock hypothesis. In opposition to Brown, Richard T. W. Arthur takes the clock
hypothesis to be already implicit in the theory. In this paper I will present a
view different from these authors by recovering Einstein's notion of natural
clock and showing its relevance to the debate
The renormalization of charge and temporality in quantum electrodynamics
In this article it is intended a closer look at the renormalization procedure used in quantum electrodynamics to cope with the divergent integrals that appear in higher-order calculations within the theory. The main focus will be the charge renormalization that reveals, in a clearer way than the mass renormalization, structural limitations present in quantum electrodynamics that are even more aggravating than the ones usually pointed at when considering the renormalization procedure. In this way we see that the possibility of charge renormalization is due to limitations of the theory in the temporal description of the interactions
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