Entanglement of primordial fluctuation

• Project/Area Number: 23540297
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University
• Principal Investigator: YASUSADA Nambu 名古屋大学, 理学(系)研究科(研究院), 准教授 (40212112)
• Project Period (FY): 2011-04-28 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2014: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2013: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2012: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2011: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
• Keywords: entanglement / inflation / quantum correlation / detector model / negativity / エンタングルメント / 量子マスター方程式 / 繰り込み群 / 量子ゆらぎ / 量子ゆらぎとエンタングルメント / 古典化 / wave optics / wave scattering / detector / 量子相関 / インフレーション

Outline of Final Research Achievements

We investigate entanglement structure of a quantum field in the inflationary universe using a particle detector model. Entanglement of the quantum field can be detectable by analyzing quantum correlation between two detectors interacting with the quantum field. We found that it is impossible to detect entanglement of the quantum field for detectors separated with distances larger than the Hubble horizon scale. This result implies that the quantum field in the inflationary universe loses its quantum nature for super Horizon scale and can be treated as a classical field.

Research Products

• [Journal Article] 宇宙初期ゆらぎのエンタングルメント (2014)
  • Author(s): 南部保貞
  • Journal Title: 日本物理学会誌 Volume: 11 Pages: 763-770
  • Peer Reviewed
• [Journal Article] Classical and quantum correlation of quantum fluctuation (2014)
  • Author(s): 南部保貞
  • Journal Title: Journal of Physics: Conference Series Volume: 484 Pages: 112067-112067
  • DOI: 10.1088/1742-6596/484/1/012067
  • Peer Reviewed
• [Journal Article] 「光子の裁判」と宇宙の古典性 (2014)
  • Author(s): 南部保貞
  • Journal Title: 数理科学 Volume: 1 Pages: 45-50
  • Peer Reviewed
• [Journal Article] Entanglement Structure in Expanding Universes (2013)
  • Author(s): 南部保貞
  • Journal Title: Entropy Volume: 15 Issue: 5 Pages: 1847-1874
  • DOI: 10.3390/e15051847
  • Peer Reviewed
• [Journal Article] Viewing black holes by waves (2013)
  • Author(s): 南部保貞
  • Journal Title: Classical and Quantum Gravity Volume: 30 Issue: 17 Pages: 175002-175002
  • DOI: 10.1088/0264-9381/30/17/175002
  • Peer Reviewed
• [Journal Article] Wave optics and image formation in gravitational lensing (2013)
  • Author(s): Y. Nambu
  • Journal Title: Int. J. Astro. Astrophys. Volume: 3 Pages: 1-7
  • Peer Reviewed
• [Journal Article] Wave optics and image formation in gravitational lensing (2013)
  • Author(s): Y. Nambu
  • Journal Title: Journal of Physics Conference Series Volume: 410 Pages: 12036-12036
  • Peer Reviewed
• [Journal Article] Classical and Quantum Correlations of Scalar Field in the Inflationary Universe (2011)
  • Author(s): Y. Nambu
  • Journal Title: Phys. Rev. D Volume: 84
  • Peer Reviewed
• [Presentation] Coarse graining approximationを課した量子マスター方程式のもとでの定常状態 (2014)
  • Author(s): 久木田真吾，南部保貞
  • Organizer: 量子情報技術研究会
  • Place of Presentation: 東北大学
  • Year and Date: 2014-11-17
• [Presentation] CGA master equation and entanglement structure (2014)
  • Author(s): 久木田真吾，南部保貞
  • Organizer: YITP Workshop on Quantum Information Physics
  • Place of Presentation: 京都大学基礎物理学研究所
  • Year and Date: 2014-08-08
• [Presentation] Wave scattering by black holes (2014)
  • Author(s): 南部保貞
  • Organizer: Black hole 磁気圏勉強会
  • Place of Presentation: 熊本大学
  • Invited
• [Presentation] 初期宇宙とエンタングルメント (2013)
  • Author(s): 南部保貞
  • Organizer: 基研研究会：量子情報物理学
  • Place of Presentation: 京都大学基礎物理学研究所
  • Invited
• [Presentation] Viewing black holes by waves (2013)
  • Author(s): 南部保貞
  • Organizer: 日本物理学会
  • Place of Presentation: 高知大学
• [Presentation] Viewng Black Holes by Waves (2013)
  • Author(s): Y. Nambu
  • Organizer: The 6th workshop on black hole maganetosphere
  • Place of Presentation: 清華大学（台湾）
  • Invited
• [Presentation] Entanglement structure in expanding unvierses (2012)
  • Author(s): Y. Nambu
  • Organizer: Quantum Vacuum Kawatabi 2012
  • Place of Presentation: 東北大学
  • Invited
• [Presentation] Black Hole時空におけるwave opticsとblack holeのimaging (2012)
  • Author(s): Y. Nambu
  • Organizer: 銀河中心ブラックホール2012
  • Place of Presentation: JAXA
  • Invited
• [Presentation] Classical and quantum correlation of quantum fluctuation (2011)
  • Author(s): Y. Nambu
  • Organizer: ICGC2011
  • Place of Presentation: India