891 citations · 2.9k across the 74 of their papers we have counts for
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Second variational derivative of gauge-natural invariant Lagrangians and conservation laws
M. Francaviglia, M. Palese, E. Winterroth
We consider the second variational derivative of a given gauge-natural invariant Lagrangian taken with respect to (prolongations of) vertical parts of gauge-natural lifts of infini…
f(R) theories of gravity in Palatini approach matched with observations
S. Capozziello, V. F. Cardone, M. Francaviglia
We investigate the viability of f(R) theories in the framework of the Palatini approach as solutions to the problem of the observed accelerated expansion of the universe. Two physi…
Conformal aspects of Palatini approach in Extended Theories of Gravity
Gianluca Allemandi, Monica Capone, Salvatore Capozziello +1
The debate on the physical relevance of conformal transformations can be faced by taking the Palatini approach into account to gravitational theories. We show that conformal transf…
Accelerated Cosmological Models in Ricci squared Gravity
G. Allemandi, A. Borowiec, M. Francaviglia
Alternative gravitational theories described by Lagrangians depending on general functions of the Ricci scalar have been proven to give coherent theoretical models to describe the…
Generalized Bianchi identities in gauge-natural field theories and the curvature of variational principles
M. Francaviglia, M. Palese, E. Winterroth
By resorting to Noether's Second Theorem, we relate the generalized Bianchi identities for Lagrangian field theories on gauge-natural bundles with the kernel of the associated gaug…
Accelerated Cosmological Models in First-Order Non-Linear Gravity
Gianluca Allemandi, Andrzej Borowiec, Mauro Francaviglia
The evidence of the acceleration of universe at present time has lead to investigate modified theories of gravity and alternative theories of gravity, which are able to explain acc…
Boundary Conditions, Energies and Gravitational Heat in General Relativity (a Classical Analysis)
M. Francaviglia, M. Raiteri
The variation of the energy for a gravitational system is directly defined from the Hamiltonian field equations of General Relativity. When the variation of the energy is written i…