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Por qué la constante cosmológica es pequeña y positiva
Paul J Steinhardt1, Neil Turok
1Joseph Henry Laboratories, Princeton University, Princeton, NJ 08544, USA. steinh@princeton.edu
Science (New York, N.Y.)
|May 6, 2006
Resumen
Un modelo de universo cíclico ofrece una solución al pequeño problema de la constante cosmológica. Este modelo presenta un mecanismo dinámico que relaja naturalmente la densidad del vacío, explicando la pequeña y positiva constante cosmológica observada.
Área de la Ciencia:
- Cosmología Cosmología.
- Física teórica es la física teórica.
Sus antecedentes:
- El problema de la constante cosmológica es un desafío importante en la cosmología moderna.
- Los modelos convencionales del Big Bang luchan por explicar el pequeño valor observado de la constante cosmológica.
Objetivo del estudio:
- Proponer un modelo de universo cíclico que aborde el problema de la constante cosmológica.
- Introducir un mecanismo dinámico para relajar las contribuciones de energía de vacío.
Principales métodos:
- Investigando un modelo cosmológico cíclico.
- Analizando el comportamiento de la densidad del vacío y los tiempos de relajación.
Principales resultados:
- Un modelo cíclico naturalmente incorpora un mecanismo para relajar la constante cosmológica.
- El tiempo de relajación aumenta exponencialmente con la disminución de la densidad del vacío.
Conclusiones:
- El modelo cíclico propuesto explica por qué la constante cosmológica es pequeña y positiva hoy en día.
- Casi todo el espacio pasa la mayor parte de su tiempo en un estado con una pequeña constante cosmológica.
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