弱いレンズと銀河の速度から大スケールでの一般相対性理論の確認
Reinabelle Reyes1, Rachel Mandelbaum, Uros Seljak
1Princeton University Observatory, Peyton Hall, Princeton, New Jersey 08544, USA. rreyes@astro.princeton.edu
Nature
|March 12, 2010
まとめ
一般相対性理論とは
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 重力物理学 重力物理学
背景:
- 一般相対性理論は,現代の宇宙学の基礎である.
- 宇宙学的スケールでのその妥当性は,厳格なテストを必要とします.
- 新しいテストであるE ((G)) は,重力レンズ,銀河のクラスタリング,構造の成長率を組み合わせています.
研究 の 目的:
- 一般相対性理論の適用性を宇宙学的スケールで検証する.
- 銀河バイアスに無感であるE(G) パラメータを測定するために.
- 測定されたE (((G) を一般相対性理論と改変重力理論からの予測と比較する.
主な方法:
- 大規模な重力レンズ,銀河のクラスタリング,構造の成長率を組み合わせた新しい量E (((G) を利用しました.
- このパラメータに対して無感な組み合わせを用いて,銀河バイアスに対する頑丈性を確保した.
- 数十メガパーセックの長さスケールのデータを分析した.
主要な成果:
- 測定されたE (((G) は0.39 ± 0.06.06です.
- この値は,約0.4.4の一般相対論的予測と一致しています.
- テンソール-ベクトル-スケーラー重力モデルは除外されたが,f (((R)) 理論モデルはまだ可能である.
結論:
- この発見は,宇宙学的スケールでの一般相対性理論の妥当性を裏付けている.
- f ((R)) 重力モデルを除外するために,測定不確実性のさらなる削減が必要である.
- この研究は,宇宙における重力の強固なテストを提供します.
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