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Blast Quantification Using Hopkinson Pressure Bars
Published on: July 5, 2016
原子干渉計によるニュートンの重力定数の測定
J B Fixler1, G T Foster, J M McGuirk
1Department of Physics, Stanford University, Stanford, CA 94305-4060, USA.
まとめ
研究者は原子干渉計を用いてニュートンの重力定数 (G) を測定した. この独立した方法により,G = 6.693 x 10^-11 m^3 kg^-1 s^-2 が得られ,既存の重力測定値の検証に極めて重要な結果となった.
科学分野:
- 基礎物理学の基礎について
- メトロロジー・メトロロジー
- 重力物理学 重力物理学とは重力物理学です.
背景:
- ニュートンの重力定数 (G) は物理学の基本定数である.
- Gの正確な測定は,重力理論をテストし,質量ベースの相互作用を理解するために不可欠です.
- Gを測定する従来の方法は,体系的なエラーに脆弱です.
研究 の 目的:
- ニュートンの重力定数 (G) を新しい原子干渉計技術を使用して測定する.
- Gの独立した測定を行い,既存の値のクロス検証を行う.
- 従来のG測定における潜在的なシステマティックエラーに対処するために.
主な方法:
- 原子干渉測定に基づく重力グラディオメーターを使用した.
- レーザーで冷却されたセシウム (Cs) 原子の微分加速を測定した.
- 重力場の変化を検出するために,よく特徴づけられた鉛 (Pb) 質量を移動させた.
主要な成果:
- G = 6.693 x 10^-11 m^3 kg^-1 s^-2.の測定値が報告されました.
- 平均値の標準誤差が +/-0.027 x 10^-11 m^3 kg^-1 s^-2.2 であった.
- +/-0.021 x 10^-11 m^3 kg^-1 s^-2.のシステマティックエラーが判定されました.
結論:
- 原子干渉測定法は,Gの正確で独立した測定を提供します.
- この結果は,引力のニュートン定数値を精錬するための継続的な努力に寄与しています.
- 独立した測定は,基本定数の決定における体系的なエラーを特定し,軽減するために不可欠です.
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