32 research outputs found
Prehistory of Transit Searches
Nowadays the more powerful method to detect extrasolar planets is the transit
method. We review the planet transits which were anticipated, searched, and the
first ones which were observed all through history. Indeed transits of planets
in front of their star were first investigated and studied in the solar system.
The first observations of sunspots were sometimes mistaken for transits of
unknown planets. The first scientific observation and study of a transit in the
solar system was the observation of Mercury transit by Pierre Gassendi in 1631.
Because observations of Venus transits could give a way to determine the
distance Sun-Earth, transits of Venus were overwhelmingly observed. Some
objects which actually do not exist were searched by their hypothetical
transits on the Sun, as some examples a Venus satellite and an infra-mercurial
planet. We evoke the possibly first use of the hypothesis of an exoplanet
transit to explain some periodic variations of the luminosity of a star, namely
the star Algol, during the eighteen century. Then we review the predictions of
detection of exoplanets by their transits, those predictions being sometimes
ancient, and made by astronomers as well as popular science writers. However,
these very interesting predictions were never published in peer-reviewed
journals specialized in astronomical discoveries and results. A possible
transit of the planet beta Pic b was observed in 1981. Shall we see another
transit expected for the same planet during 2018? Today, some studies of
transits which are connected to hypothetical extraterrestrial civilisations are
published in astronomical refereed journals. Some studies which would be
classified not long ago as science fiction are now considered as scientific
ones.Comment: Submiited to Handbook of Exoplanets (Springer
Gardens of happiness: Sir William Temple, temperance and China
This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordSir William Temple, an English statesman and humanist, wrote āUpon the
Gardens of Epicurusā in 1685, taking a neo-epicurean approach to happiness
and temperance. In accord with Pierre Gassendiās epicureanism, āhappinessā is
characterised as freedom from disturbance and pain in mind and body, whereas
ātemperanceā means following nature (Providence and oneās physiopsychological constitution). For Temple, cultivating fruit trees in his garden was
analogous to the threefold cultivation of temperance as a virtue in the humoral
body (as food), the mind (as freedom from the passions), and the bodyeconomic (as circulating goods) in order to attain happiness. A regimen that was
supposed to cure the malaise of Restoration amidst a crisis of unbridled
passions, this threefold cultivation of temperance underlines Templeās reception
of China and Confucianism wherein happiness and temperance are highlighted.
Thus Templeās āgardens of happinessā represent not only a reinterpretation of
classical ideas, but also his dialogue with China.European CommissionLeverhulme Trus
How Galileo dropped the ball and Fermat picked it up
This paper introduces a little-known episode in the history of physics, in which a mathematical proof by Pierre Fermat vindicated Galileo's characterization of freefall. The first part of the paper reviews the historical context leading up to Fermat's proof. The second part illustrates how a physical and a mathematical insight enabled Fermat's result, and that a simple modification would satisfy any of Fermat's critics. The result is an illustration of how a purely theoretical argument can settle an apparently empirical debate
Early Modern Semiotics
The term āsemioticsā appears for the first time at the end of John Lockeās An Essay Concerning Human Understanding (1690) in a passage referred to by Charles Sanders Peirce. Nevertheless, it would be incorrect to describe early modern theories of signs in the terms of contemporary semiotics. On the one hand, they must be contextualized in the traditional Aristotelian and Augustinian framework of Scholasticism. In fact, in many respects, and despite their undeniable modernity, the most emblematic authors of early modern semiotics, in particular Locke and the authors of Port-Royal, developed their theories along this traditional model, favoring a linguistic paradigm. On the other hand, authors like Thomas Hobbes, Pierre Gassendi, and Pierre Bayle built a renewed semiotic theory headed toward epistemology