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Time, atemporality and the Trinitarian nature of God in Plato’s philosophical heritage
The paper addresses an apparently unsolvable philosophical question: can the Christian Dogma of the Trinitarian nature of God be rationally explained? The authors argue that the conflict between fides and ratio can be resolved by a novel interpretation of the concept of time within a new philosophical paradigm: the Purposeful Evolution Theory (PET), where time, as in Plato, is a movable image of Eternity. In this paper, the PET is used to explain the Christian Dogma of Trinity through a deductive reasoning centred on the concept of atemporality. The Purposeful Evolution Theory has strict links with Plato’s philosophy and represents a key for a systematic interpretation of Plato’s unwritten doctrines. The authors argue that Plato’s unwritten doctrines already addressed and partially solved the problem of Eternity and Time, indirectly giving a reason-based explanation of the Trinitarian Nature of God and His Goodness, before it was even revealed
GRBs with optical afterglow and known redshift: a statistical study
We present a correlation between two intrinsic parameters of GRB optical
afterglows. These are the isotropic luminosity at the maximum of the light
curve (Lpeak) and the time-integrated isotropic energy (Eiso) radiated after
the observed maximum. We test the correlation between the logarithms of (Eiso)
and (Lpeak) and finally we value the effect of the different samples of GRBs in
according with the first optical observation reduced to proper time.Comment: To be published in the proceedings of the conference "SWIFT and GRBs:
Unveiling the Relativistic Universe", Venice, June 5-9, 200
D-Brane Interactions in a Gravitational Shock Wave Background
We study D-branes in the background of a gravitational shock wave. We
consider the case of parallel D-branes located on opposite sides with respect
to the shock wave. Their interaction is studied by evaluating the cylinder
diagram using the boundary states technique. Boundary states are defined at
each D-brane and their scalar product is evaluated after propagation through
the shock wave. Taking the limit where the gravitational shock wave vanishes we
show that the amplitude evaluated is consistent with the flat space-time
result.Comment: To be published in Modern Physics Letters A, revised version with
references added, 12 page
ASCA and BeppoSAX observations of the peculiar X-ray source 4U1700+24/HD154791
The X-ray source 4U1700+24/HD154791 is one of the few galactic sources whose
counterpart is an evolved M star. In X-rays the source shows extreme erratic
variability and a complex and variable spectrum. While this strongly suggests
accretion onto a compact object, no clear diagnosis of binarity was done up to
now. We report on ASCA and BeppoSAX X-ray broad band observations of this
source and on ground optical observations from the Loiano 1.5 m telescope.Comment: 5 pages, 4 figures, uses aipproc.sty, to appear in Proceedings of the
Fifth Compton Symposiu
An effective numerical modelling strategy for FRCM strengthened curved masonry structures
Fabric Reinforced Cementitious Matrix (FRCM) composites are currently considered a very effective solution for strengthening masonry constructions. However, the mechanical interactions governing the response and the strength of FRCM reinforced masonry structures are very complex, especially in the case of curved structures. Moreover, these interactions involve several interfaces between different materials. Thus, the development of accurate numerical models for curved FRCM reinforced masonry structures comes up against several difficulties, and models too complex for practical applications can be obtained. In addition, several mechanical parameters needed for the calculations are generally inaccessible by conventional experimental tests.
Here, a suitable numerical modelling strategy for FRCM strengthened curved masonry structures is proposed to combine the accuracy in simulating the actual behaviour in terms of stiffness, strength and collapse mechanisms with a reasonable simplicity, making the proposed approach usable also by practitioners, by adopting commercial codes and at a moderate computational effort. The relatively small number of mechanical parameters characterizing the model can be determined by ordinary experimental tests on materials or by literature formulations.
The proposed modelling strategy is validated with respect to experimental data found in literature concerning a FRCM reinforced masonry barrel vault, and then is employed for studying the seismic capacity of the vault through a pushover analysis. A broad sensitivity analysis sheds light on the effect of variations of the mechanical parameters on the predicted overall behaviour, showing the robustness of the results obtainable through the proposed approach concerning inaccuracies in the determination of the parameters often very difficult to determine by ordinary experimental tests on masonry structures.Funding: Financial support from ReLUIS (Italian Department of Civil Protection) and from the Italian Ministry of University and Research (MUR) in the framework of Project PRIN2020 #20209F3A37 is gratefully acknowledged
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