| Revue: | Brazilian journal of physics |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000335815 |
| ISSN: | 0103-9733 |
| Autores: | Rami, El-Nabulsi Ahmad1 |
| Instituciones: | 1Cheju National University, Department of Nuclear and Energy Engineering, Ara-dong 1, 690-756, South Korea, Jeju. Corea del Sur |
| Año: | 2009 |
| Periodo: | Sep |
| Volumen: | 39 |
| Número: | 3 |
| Paginación: | 574-582 |
| País: | Brasil |
| Idioma: | Inglés |
| Tipo de documento: | Artículo |
| Enfoque: | Experimental, analítico |
| Resumen en inglés | Higher dimensional cosmological implications ofa decay law for the cosmological constant term are analyzed. Three independent cosmological models are explored mainly: 1) - In the first model, the effective cosmological constant was chosen to decay with times like Λeffective = Ca-2 + D(b/ai)2 where aiis an arbitrary scale factor characterizing the isotropic epoch which proceeds the graceful exit period. Further, the extra-dimensional scale factor decays classically like b(t) ≈ ax (t),xisareal negative number. 2) - In the second model, we adopt in addition to Λeffective = Ca-2 + D(b/ai)2 the phenomenological law b(t) = a(t) exp(—Qt) as we expect that at the origin of time, there is no distinction between the visible and extra dimensions; Qis a real number. 3) -In the third model, we study a Λ—decaying extra-dimensional cosmology with a static traversable wormhole in which the four-dimensional Friedmann-Robertson-Walker spacetime is subject to the conventional perfect fluid while the extra-dimensional part is endowed by an exotic fluid violating strong energy condition and where the cosmological constant in (3+n+1) is assumed to decays like Λ(a) = 3Ca-2. The three models are discussed and explored in some details where many interesting points are revealed |
| Disciplinas: | Física y astronomía |
| Palabras clave: | Astronomía, Energía oscura, Constante cosmológica, Agujeros de gusano, Superaceleración |
| Keyword: | Physics and astronomy, Astronomy, Dark energy, Cosmological constant, Worm holes, Superacceleration |
| Texte intégral: | Texto completo (Ver HTML) |
