1,721,166 research outputs found
Luisa Bertacchi e la Casa delle Bestie ferite: uno scavo nello scavo
Full text linkIl contributo si concentra sugli interventi dell'archeologa Luisa Bertacchi ad Aquiliea presso l'area della cd. Casa delle Bestie ferite negli anni 1961-1962. A partire dal 2007 l'Università degli studi di Padova ha ripreso le indagini della domus, con l'obiettivo di ricostruirne la storia edilizia all'interno delle dinamiche insediati del settore settentrionale dell'antica colonia adriatica
From weak interaction to gravity
No full textWe follow an old suggestion made by Stueckelberg that there exists an intimate connection between weak interaction and gravity, symbolized by the relationship between the Fermi and Newton's constants. We analyze the hypothesis that the effect of matter upon the metric that represents gravitational interaction in general relativity is an effective one. This leads us to consider gravitation to be the result of the interaction of two neutral spinorial fields (g-neutrinos) ψg and ωg with all kinds of matter and energy. We present three examples with only one g-neutrino: two static and spherically symmetric configurations and a cosmological framework for an isotropic dynamical universe. Without self-interaction, the associated effective geometry is precisely the Schwarzschild metric. On the other hand, a self-interacting g-neutrino generates a new gravitational black hole
Gravitational waves in the spinor theory of gravity
No full textWe analyze the gravitational waves within the Spinor Theory of Gravity (STG) and compare it with the General Relativity proposal. In the case of STG, a gravitational wave may occur if the effective gravitational metric induced by the spinorial field is Ricci flat
Vita quotidiana nell'Aquileia romana
No full textIl contributo si inserisce nell'ambito delle ricerche su Aquileia e il suo territorio e fa il punto sulla vita privata ricostruita attraverso la documentazione delle testimonianze archeologiche
Moenibus et portu celeberrima. Aquileia: storia di una città
No full textIl volume di cui la scrivente ha curato l'impostazione, scegliendo i collaboratori e scrivendo la premessa e un contributo, intende fare il punto sulle conoscenze dell'archeologia aquileiese acquisite nel corso dell'ultimo trentennio nella prospettiva di un grande piano di valorizzazione della citta
Geometric scalar theory of gravity beyond spherical symmetry
No full textWe construct several exact solutions for a recently proposed geometric scalar theory of gravity. We focus on a class of axisymmetric geometries and a big-bang-like geometry and discuss their Lorentzian character. The axisymmetric solutions are parametrized by an integer angular momentum l. The l=0 (spherical) case gives rise to the Schwarzschild geometry. The other solutions have naked singular surfaces. While not a priori obvious, all the solutions that we present here are globally Lorentzian. The Lorentzian signature appears to be a robust property of the disformal geometries solving the vacuum geometric scalar theory of gravity equations
Is the electromagnetic field responsible for the cosmic acceleration in late times?
No full textWe show that in the realm of general relativity, a nonminimal coupling between the electromagnetic and the gravitational fields may produce an era of accelerated expansion
The Cosmological Constant and a Scalar Field Coupled non Minimally to Gravity
No full textWe show that the combined minimal and non minimal interaction with the gravitational field may produce the generation of a cosmological constant without self-interaction of the scalar field. In the same vein we analyze the existence of states of a scalar field that by a combined interaction of minimal and non minimal coupling with the gravitational field can exhibit an unexpected property, to wit, they are acted on by the gravitational field but do not generate gravitational field. In other words, states that seems to violate the action-reaction principle. We present explicit examples of this situation in the framework of a spatially isotropic and homogeneous universe
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