Zobrazeno 1 - 10
of 62
pro vyhledávání: '"Alex Giacomini"'
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 2, Pp 1-16 (2021)
Abstract In this paper we perform systematic investigation of all possible solutions with static compact extra dimensions and expanding three-dimensional subspace (“our Universe”). Unlike previous papers, we consider extra-dimensional subspace to
Externí odkaz:
https://doaj.org/article/d8ad9b21fe7a4476b07c0d5701a14407
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 81, Iss 1, Pp 1-23 (2021)
Abstract In this paper, we construct the first analytic examples of $$(3+1)$$ ( 3 + 1 ) -dimensional self-gravitating regular cosmic tube solutions which are superconducting, free of curvature singularities and with non-trivial topological charge in
Externí odkaz:
https://doaj.org/article/59f7689aae55468ebc93ac09b6538a84
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 10, Pp 1-14 (2020)
Abstract We investigate the quintessence scalar field model modified by the generalized uncertainty principle in the background of a spatially flat homogeneous and isotropic universe. By performing a dynamical system analysis we examine the nature of
Externí odkaz:
https://doaj.org/article/d0d3e7411cac4fd4a24094fa90b998c2
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 80, Iss 3, Pp 1-31 (2020)
Abstract In the present article we study the cosmological evolution of a two-scalar field gravitational theory defined in the Jordan frame. Specifically, we assume one of the scalar fields to be minimally coupled to gravity, while the second field wh
Externí odkaz:
https://doaj.org/article/73ef5077fb3c43e2a69587e60e1edae1
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 79, Iss 10, Pp 1-9 (2019)
Abstract A new topological invariant quantity, sensitive to the analytic structure of both fermionic and bosonic propagators, is proposed. The gauge invariance of our construct is guaranteed for at least small gauge transformations. A generalization
Externí odkaz:
https://doaj.org/article/7208e390041d43f7b0e6650410e38abc
Autor:
Alex Giacomini, Marcello Ortaggio
Publikováno v:
Journal of High Energy Physics, Vol 2019, Iss 9, Pp 1-27 (2019)
Abstract We consider a class of ansätze for the construction of exact solutions of the Einstein-nonlinear σ-model system with an arbitrary cosmological constant in (3+1) dimensions. Exploiting a geometric interplay between the SU(2) field and Killi
Externí odkaz:
https://doaj.org/article/516e7100d20f455e800452981ceb98f7
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 78, Iss 9, Pp 1-10 (2018)
Abstract The physical properties of static analytic solutions which describe black brane geometries are discussed. In particular we study the similarities and differences of analytic black brane/string solutions in the Einstein and Jordan frames. The
Externí odkaz:
https://doaj.org/article/92447c065ed04410bb940a2b3eb9673b
Publikováno v:
Physics Letters B, Vol 777, Iss , Pp 361-368 (2018)
A new family of analytical solutions in a four dimensional static spacetime is presented for f(R)-gravity. In contrast to General Relativity, we find that a non trivial black brane/string solution is supported in vacuum power law f(R)-gravity for app
Externí odkaz:
https://doaj.org/article/3583d9120be34c83a59f8540062c6801
Publikováno v:
Physics Letters B, Vol 776, Iss C, Pp 236-241 (2018)
An exact hairy asymptotically locally AdS black hole solution with a flat horizon in the Einstein-nonlinear sigma model system in (3+1) dimensions is constructed. The ansatz for the nonlinear SU(2) field is regular everywhere and depends explicitly o
Externí odkaz:
https://doaj.org/article/ffd9e18a628944b2ab5817232ee59aa5
Publikováno v:
European Physical Journal C: Particles and Fields, Vol 77, Iss 7, Pp 1-11 (2017)
Abstract For a family of Horndeski theories, formulated in terms of a generalized Galileon model, we study the integrability of the field equations in a Friedmann–Lemaître–Robertson–Walker space-time. We are interested in point transformations
Externí odkaz:
https://doaj.org/article/00777193a0c84a7e9b9bead24e3a9afe