Variation in the frequency separations with activity and impact on stellar parameter determination

Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been seen, even though the Sun is a low-activity star. In this paper, we discuss these variations and their impact on the determination of the stellar parameters (radius, mass and age) for the Sun. Using the data from maximum and minimum activity, we fitted an age for the Sun that differs on average by 0.2 Gyr: slightly older during minimum activity. The fitted radius is also lower by about 0.5% for the solar effective temperature during minimum.Comment: to be published in JPCS to be published in JPC

El ver y lo visto según el lugar "donde poner las cosas" en Piero della Francesca

The act of seeing and what is seen according to the place where 40 puf things. (ponere le cose) in Piero della Francesca On the one hand, we can say that the artist conceives of his painting as if it were a world; on the other hand, we can say that he also thinks of the world as painting. Betweenthe things of the world in its physical presence, the mind that thinks of them and their representation, the Renaissance period tried to discover a logical relationship. So, the author tries here to find out this relationship between the theory of painting in Renaissance period (from De prospectiva pigendi of Piero della Francesca) and what would be, in general terms, a theory of knowledge. The reason, which is also required in the act of viewing and being conscious of the world that is so seen. So, watching something must already be for the painter some kind of intellectual act which points towards the phenomenic presentness of the same thing, just to fit it in a reasonable process of viewing. Here is, of course, the neoplatonist idea. But then, the work of painting such a thing according to the painting itself is nothing but a methodical construction of the world of the painter's consciousness. As it is prepared by the N. de Cusa philosophy, here appears the concept of a subject which places itself somewhere between the athings of the world), and his own, immediate perception: just at the conceptual point where the world is represented and Piero wanted to put things, ponere le cose. So it is: a locationwhich is not coincident with the physical things nor with the real eye, and where the human world grows figured out as a mental one

Coito, luego existo. Acerca de la ciudad contemporánea

Dos models urbans, el tradicional de la ciutat-recinte i I'actual de una ciutat-flux, es refereixen a dues modalitats d'espai: un de sentit intencional i organitzat, que s'actualitza en la significació, i un altre de sentit obert, múltiple o difús que es propaga sense significar. Alhora, dos models de comunitat: un de modern, il.lustrat per una societat-maquina de vapor (Levi-Strauss) que ja s'ha devorat a si mateixa, i un altre de postmodern, avui vigent, donat per una societat-ameba multiforme i transparent que es multiplica infinitament. A aquest darrer model de societat democratica i capitalista, propi de les grans aglomeracions urbanes que s'aboquen a cobrir el planeta, li correspon una triple llibertat: somatica (sexe alliberat), d'acció (joc per a la vida) i d'expressió (llenguatge democratitzat). Primer, el culte contemporani a la salut fa del cos un instrument de <<bona vida,) lubricat per un sexe profitósque deixata I'amor amb I'orgasme. Segon, la vida quotidiana es un joc de forces en pugna (pretensió/tensiÓ/distensió) o un simple entreteniment que liquida la realitat amb la representació. Tercer, I'actual Ús del llenguatge -en els mass-media: política, esports, publicitat- inhabilita el pensament amb la paraula, neutralitza la informació amb la comunicació, nega el sentit amb I'opinió (doxa), que ridiculitza amb la paradoxa. El pas del cogito ergo sumcartesia al <<coito, luego existo,, anonim en la actual cultura urbana ja esta donat: ara existir es copular.Two urban models, the traditional enclosed city and today's city in flux, account for two spatial modalities: the former, intentional and organized, acquires meaning through signification; the latter, open, multiple and diffuse, propagates without signification. Similarly, there are two community models: one of which is modern, exemplified by a steam-engine society (Levi-Strauss), which has already consumed itself; the other, identifiable today, ispostmodern, the result of an amoebic-like society, multiform and transparent, which multiplies infinitely. This model of a democratic, capitalistic society, characteristic of large urban agglomerations which spread out over the planet, possesses a triadic freedom: somatic (free love), action (life as a game) and expression (democratized language). First, the contemporary cult for healthy living has turned the body into an instrument of the ccgoodlife)), lubricated by good sex which reduces love to no more than orgasm. Second, daily life has became a game of opposing foces (pretension/tension/distension) or a simple sideshow which dilutes reality with performance. Third, the present use of language in themass-media: politics, sport, advertising strangles thought with words, neutrallzes information with communication, rejects meaning with opinion (doxa) and that in turn is ridiculed with paradox. The simple step from Cariesian cogito, ergo sum to the anonymous <<coito, luego existo)) (coito, ergo sum) in contemporary urban culture has already been taken: to exist is to copulate

Mode visibilities in radial velocity and intensity Sun-as-a-star helioseismic measurements

We analyze more than 5000 days of Sun-as-a-star radial velocity GOLF and intensity VIRGO observations to measure the visibilities of the l=0, 1, 2, and 3 modes and the m-amplitude ratios of the l=2 and 3 modes in the solar acoustic spectrum. We provide observational values that we compare to theoretical predictions.Comment: SOHO 24 / GONG 2010 conference, to be published in JPC