Search results for " early"
showing 10 items of 329 documents
Slow roll in simple non-canonical inflation
2007
17 pages, 4 figures.-- ISI Article Identifier: 000245945000008.-- ArXiv pre-print available at: http://arxiv.org/abs/astro-ph/0701343
Astrophysical constraints on extended gravity models
2015
We investigate the propagation of gravitational waves in the context of fourth order gravity nonminimally coupled to a massive scalar field. Using the damping of the orbital period of coalescing stellar binary systems, we impose constraints on the free parameters of extended gravity models. In particular, we find that the variation of the orbital period is a function of three mass scales which depend on the free parameters of the model under consideration; we can constrain these mass scales from current observational data.
Renormalisation group improvement in the stochastic formalism
2019
We investigate compatibility between the stochastic infrared (IR) resummation of light test fields on inflationary spacetimes and renormalisation group running of the ultra-violet (UV) physics. Using the Wilsonian approach, we derive improved stochastic Langevin and Fokker-Planck equations which consistently include the renormalisation group effects. With the exception of stationary solutions, these differ from the naive approach of simply replacing the classical potential in the standard stochastic equations with the renormalisation group improved potential. Using this new formalism, we exemplify the IR dynamics with the Yukawa theory during inflation, illustrating the differences between …
Revising the Predictions of Inflation for the Cosmic Microwave Background Anisotropies
2009
4 pages, 1 figure.-- PACS nrs.: 98.70.Vc; 11.10.Gh; 98.80.Cq.-- ArXiv pre-print available at: http://arxiv.org/abs/0901.0439
On gravitational waves in Born-Infeld inspired non-singular cosmologies
2017
We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisatio…
Un nuovo assetto per il quartiere della Kalsa nel Cinquecento: l'addizione urbana del piano di porta dei Greci
2013
Il saggio porta alla luce, attraverso significative acquisizioni documentarie, l'unica operazione di addizione urbana che la città di Palermo, ancora murata, abbia conosciuto: quella che vide l'ampliamento del quartiere della Kalsa verso mare e il ridisegno della sua cinta muraria, attuati su progetto dell'ingegnere regio Pedro Prado, ma con il diretto coinvolgimento del loro promotore, il viceré Juan de Vega. La ricerca si sofferma anche sugli aspetti del cantiere delle nuove fortificazioni 'alla moderna', nonché su quelli artistici e stilistici legati alla edificazione di una nuova porta urbica, caricata di forti valori simbolici, e al radicamento del linguaggio classicista nella Sicilia …
'Forgotten Missionaries: St Augustine of Canterbury in Anglo-Saxon and Post-Conquest England’
2014
The essay provides a full overview of the alternate fortune of the cult of St Augustine of Canterbury and other missionaries, who hold a distinctive place in Anglo-Saxon hagiography. The essay takes into examination both literary and liturgical witnesses and both pre- and post-Conquest texts, in Latin and the vernacular. The narrative of the mission and of Augustine himself offered by Bede, although inevitably partial, shaped all the successive representations of the saint in the few literary witnesses dating from the Anglo-Saxon period. The Historia ecclesiastica gentis Anglorum will remain the major source also in post-Conquest England and be largely drawn upon by Goscelin. For its part, …
Joan Roís de Corella, la seua vida i el seu entorn: noves dades per a la història de la cultura en la València del segle xv
2014
This article offers a full updating of the biographical records of the writer Joan Roís de Corella (1435-1497) and his family: his great-grandparents, grandparents, parents, siblings and children. All data are presented in a systematic way, generation by generation, and a new vision of the writer himself is offered. In its documentary section, 432 documents are transcribed or summarised, dating from 1373 to 1516. A broad range of new archival data is presented; other previously known data are corrected or improved. Some examples: Joan Roís de Corella had four children: Magdalena (born 1459), Maria, Joan and Estefania, the latter two by Isabel Martínez de Vera. Joan Roís de Corella was widel…
Die Embryologie im Spannungsfeld zwischen Tradition und Empirie.
1991
Already in classical antiquity people dealt with the principle of formation, developing different theories. Researchers in the renaissance, working in the conflict zone between tradition and experience, tried to prove one or the other of these theories by the means of new observations, especially of chicken development. Aldrovandi was the first to see the real principle of formation of the hen's egg, i. e. the blastodisc, but he didn't recognize the importance of his discovery due to his close adherence to Aristotle in the theoretical field. Fabricius even thought that traditional knowledge was of more importance than his own excellent observations. Parisano was the first to succeed in maki…
El poderoso y su doble. Amis y Amiles en el teatro clásico español
2017
El propósito de este artículo es doble. Por un lado, se pretende estudiar dos muestras de la versión teatral española de la leyenda de Amis y Amiles, representada por La sutil maraña de los dos fieles y parescidos amigos Luis y Alejandro y los sucesos de Alejandro y cómo por su saber vino a ser rey de Egipto (BNE, mss. 15049) y Los pronósticos de Alejandre (BNE, mss. 16064) y su conexión con el capítulo 21 de los Siete Sabios de Roma. El análisis de la estructura métrica de estos dramas pone de manifiesto que debieron componerse durante las dos últimas décadas del siglo XVI. Por otro lado, se intenta profundizar en el contexto educativo del futuro Felipe III para explorar los significados q…