負のエントロピーの熱力学的な意味
Lídia del Rio1, Johan Aberg, Renato Renner
1Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland. delrio@phys.ethz.ch
Nature
|June 4, 2011
まとめ
データ消去のコストに関するランドーアの原則は,量子情報のために修正されています. データを消去する作業コストは,観測者の量子知識に依存し,潜在的に作業抽出と冷却を可能にします.
科学分野:
- 熱力学は熱力学である.
- 情報理論は情報理論である.
- 量子力学は,量子力学という
背景:
- コンピューティングによって生成される熱は,回路の小型化を妨げます.
- ランダウアの原理は,データの消去を最小限の作業コストと熱散熱と結びつけています.
- 古典的な情報の仮定は,消去コストの現在の理解を制限しています.
研究 の 目的:
- 量子情報でランドーアの原理の妥当性を調査する.
- 量子情報に関与する際のデータ消去の熱力学的コストを決定する.
- 計算と熱力学における量子情報の影響を調査する.
主な方法:
- 量子情報の存在における情報消去の理論的分析.
- 逆行できない計算を逆行可能な操作とデータ消去に分解する.
- 消去されるシステムとの量子記憶の絡み合いに関する調査.
主要な成果:
- スタンダード・ランドーワーの原理は,量子情報では成り立たない.
- 消去の作業コストは,観測者の量子情報に条件付けられたシステムのエントロピーによって決定されます.
- 条件エントロピーは直接的な熱力学的な意味を持つ.
結論:
- システムについての観察者の知識は,その消去のコストを減らす.
- 量子的な場合の負の条件エントロピーは,消去時に作業の獲得と環境の冷却を可能にします.
- 量子計算における熱生成に関する新しい境界線を提供する.
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