宇宙マイクロ波背景の弱い広角温度相関の説明として,十二面体空間トポロジー
Jean-Pierre Luminet1, Jeffrey R Weeks, Alain Riazuelo
1Observatoire de Paris, 92195 Meudon Cedex, France.
Nature
|October 10, 2003
まとめ
標準宇宙論モデルは不完全かもしれない. 新しい研究は,有限で十二面形の宇宙を示唆し,宇宙マイクロ波背景データで見られた欠落した温度相関を説明し,無限平らな宇宙理論に挑戦しています.
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
- ジオメトリ・ジオメトリ
背景:
- 標準宇宙モデル (SCM) は,暗黒エネルギーによって駆動される無限で平坦で膨張している宇宙を記述しています.
- ウィルキンソンマイクロ波アニゾトロピープローブ (WMAP) の1年目のデータは,最大の角尺度を除いて,SCMを高精度で確認しています.
研究 の 目的:
- WMAPデータとSCMの間の差異を調査し,大きな角度スケールの温度相関に関する差異を調査する.
- 観測された60度以上の相関の欠如を説明できる代替的空間幾何学を探求すること.
主な方法:
- 1年目のWMAP衛星データの分析,宇宙マイクロ波背景の温度相関に焦点を当てた.
- 有限の空間,特にポアンカレの十二面体空間をモデル化して,観測されたデータに対する説明力をテストする.
主要な成果:
- WMAPのデータは,温度相関が60度以上の角度スケールで消え去ることを示しており,無限の平らな宇宙に対するSCMの予測とは対照的です.
- ポアンカレの十二面体空間モデルは,これらの大規模な相関の欠如を,微調整なしに自然に説明します.
- このモデルは,オメガ (Omega) の宇宙密度を,およそ1.013 (>1) と,天気温度相関におけるマッチングサークルの特定のパターンを予測しています.
結論:
- 観測された宇宙マイクロ波背景の大規模な異常は,宇宙が無限で平坦ではないことを示唆しています.
- ポインカレの十二面体空間のような有限で正曲線のトポロジーは,WMAP観測に対する説得力のある代替説明を提供します.
- この幾何学的なモデルは,宇宙マイクロ波背景スペクトルにおける"欠けている電源"の問題に対する潜在的な解決を提供している.
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