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Confirmación de la relatividad general en grandes escalas a partir de la lente débil y las velocidades de las
Reinabelle Reyes1, Rachel Mandelbaum, Uros Seljak
1Princeton University Observatory, Peyton Hall, Princeton, New Jersey 08544, USA. rreyes@astro.princeton.edu
Nature
|March 12, 2010
Resumen
Relatividad general La relatividad general.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Física de la gravitación Física gravitacional es la física de las fuerzas gravitacionales.
Sus antecedentes:
- La relatividad general es el fundamento de la cosmología moderna.
- Su validez en escalas cosmológicas requiere pruebas rigurosas.
- Una nueva prueba, E(G), combina la lente gravitacional, el agrupamiento de galaxias y la velocidad de crecimiento de la estructura.
Objetivo del estudio:
- Para probar la aplicabilidad de la relatividad general en escalas cosmológicas.
- Para medir el parámetro E(G), que es insensible al sesgo de las galaxias.
- Para comparar la E (G) medida con las predicciones de la relatividad general y las teorías de la gravedad modificada.
Principales métodos:
- Utilizó una nueva cantidad E (((G) que combina lente gravitacional a gran escala, agrupación de galaxias y tasa de crecimiento de la estructura.
- Robustez asegurada contra el sesgo galáctico mediante el uso de una combinación insensible a este parámetro.
- Analizó datos en escalas de longitud de decenas de megaparsecs.
Principales resultados:
- La medida E (((G) es de 0,39 ± 0,06.
- Este valor se alinea con la predicción relativista general de aproximadamente 0.4.4.
- Se excluyó un modelo de gravedad tensor-vector-escalar, pero los modelos de la teoría f (R) siguen siendo posibles.
Conclusiones:
- Los hallazgos apoyan la validez de la relatividad general en escalas cosmológicas.
- Se necesita una mayor reducción de la incertidumbre de medición para excluir los modelos de gravedad f (R).
- Este estudio proporciona una prueba robusta de la gravedad en el universo.
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