Lectures & Reviews

2024

  • Lecture Slides: “Parity Violation in Cosmology” [45 and 60 min]
    • Graduate Program on Physics for the Universe (GPPU) at Tohoku University (September 25)
    • Lecture 1: What is parity symmetry? (PDF 6MB; last updated, September 22, 2024)
      • 1.1 Parity
      • 1.2 Pseudovector, pseudoscalar
      • 1.3 Discovery of parity violation in β-decay
      • 1.4 Helicity
      • 1.5 Parity symmetry in electromagnetism (EM)
      • 1.6 Action principle for EM
    • Lecture 2: Cosmic birefringence (PDF 22.4MB; last updated, September 22, 2024)
      • 2.1 FF˜ in the action
      • 2.2 Propagation of EM waves
      • 2.3 Parity violation in EM waves
      • 2.4 Parity violation in EM waves due to dark matter and dark energy
      • 2.5 Parity violation in the cosmic microwave background (CMB)

2023

  • Lecture Slides: “Parity Violation in Cosmology” [7 x 85 min]
    • MC Specialized Course, Department of Physics, Nagoya University (June 6–30)
    • Lecture 1: What is parity symmetry? (PDF 3.9 MB; last updated, June 5, 2023)
      • 1.1 Parity
      • 1.2 Vector and pseudovector
      • 1.3 Discovery of parity violation in β-decay
      • 1.4 Helicity
    • Lecture 2: Chern-Simons interaction (PDF 1.6 MB; last updated, June 8, 2023)
      • 2.1 Parity symmetry in electromagnetism (EM)
      • 2.2 Action principle for EM
      • 2.3 FF˜ in the action
      • 2.4 Parity violation in EM waves
    • Lecture 3: Parity violation 1: Cosmic inflation (PDF 2.1MB; last updated, June 12, 2023)
      • 3.1 Cosmic inflation
      • 3.2 EM in expanding space
      • 3.3 Quantization of Aμ during inflation
      • 3.4 Production of Aμ with FF˜
    • Lecture 4: Parity violation 1: Cosmic inflation (continued) (PDF 4.9 MB; last updated, June 26, 2023)
      • 3.5 Quantization of χ during inflation
      • 3.6 Primordial gravitational waves (GW)
      • 3.7 Parity violation in GW
    • Lecture 5: Parity violation 2&3: Dark matter and energy, and light propagation: birefringence (PDF 1.7 MB; last updated, June 26, 2023)
      • 4.1 Scalar field dark matter
      • 4.2 Evolution of χ in expanding space
      • 5.1 Scalar field dark energy
      • 6.1 Polarization of light
      • 6.2 Cosmic birefringence
    • Lecture 6: Physics of polarization of the cosmic microwave background (PDF 18.7 MB; last updated, June 26, 2023)
      • 7.1 Generation of polariation in the CMB
      • 7.2 E- and B-mode polarization
      • 7.3 Cosmic birefringence in the CMB
      • 7.4 CMB polarization from GW
    • Lecture 7: Recent observational results, their implications, and future prospects (PDF 8.8 MB; last updated, June 26, 2023)
      • 8.1 Possible sources of the observed EB power spectrum
      • 8.2 Is cosmic birefringence due to dark matter or dark energy?
      • 8.3 Signature of parity violation in the density fluctuations

2022

2020

  • Lecture Slides and Videos: “Physics of the Cosmic Microwave Background” [10 x 90 min]
    • International Max Planck Research School (IMPRS) Advanced Course (November 3–December 3; every Tuesday and Thursday)
    • Lectures have been recorded, and are available here. The links to each of the lecture videos are also available below.
      • The video plays on Chrome-based browsers and Firefox, but does not play on Safari and IE. See FAQ for more details.
      • The bold numbers within the parenthesis such as (11:56-38:19) for each topic refer to the corresponding times of the video during which we discuss that topic.
      • The recording of Lecture 9 was, unfortunately, lost due to the power failure in one of the server locations of GWDG. Too bad.
    • The chapter numbes such as [1.1, 1.2] for each topic refer to the corresponding chapter numbers of my textbook on CMB (written only in Japanese - sorry).
    • Lecture 1 (PDF 6.7MB; last updated, November 1, 2020) [video (17 min)]
      • Introduction [1.1, 1.2]
    • Lecture 2 (PDF 3.7MB; last updated, November 15, 2020) [video (69 min)]
    • Lecture 3 (PDF 4MB; last updated, November 10, 2020) [video (55 min)]
      • (0:00-11:55) Sachs-Wolfe effects [5.3] 
      • (11:56-38:19) Initial condition [5.4.1] 
      • (38:20-55:25) Gravitational lensing [5.6] 
    • Lecture 4 (PDF 10.1MB; last updated, November 10, 2020) [video (78 min); shared note on the derivation of Φ=constant during the matter era (used during 40:35-47:20)]
      • (0:00-51:30) Spherical harmonics [4.1, 4.2, 6.3] 
      • (51:31-65:50) Flat-sky (small-angle) approximation [6.2.1, 6.2.2] 
      • (65:51-77:45) The power spectrum of the Sachs-Wolfe effect [6.3.1–6.3.5] 
    • Lecture 5 (PDF 12.1MB; last updated, November 17, 2020) [video (71 min); shared note on back-of-the-envelope calculations of the sound horizon (used during 55:00-68:40)]
      • (0:00-34:57) Basics of the sound waves [8.3] 
      • (34:58-70:20) Sound horizon [9.1] 
    • Lecture 6 (PDF 4.3MB; last updated, November 17, 2020) [video (57 min); shared note on “Build a Universe” (used during 47:10-56:15)]
      • (0:00-30:03) Hydrodynamics of the photon-baryon fluid [9.2]
        • (25:55-30:03) A Golden Lesson from the history of CMB research: Don’t be afraid of studying small effects! [the column in 9.2.1]
      • (30:04-37:40) Tight-coupling approximation [9.2.1]
      • (37:41-57:10) Hands-on exercise: Build a Universe! [Enable “Flash Player” before using this web tool.]
    • Lecture 7 (PDF 6.1MB; last updated, November 24, 2020) [video (81 min)]
      • (0:00-11:20) Conserved curvature perturbation [5.4.1]
      • (11:21-36:36) Locations of the acoustic peaks [9.3]
      • (36:37-56:29) Damping of the sound waves [9.2.3]
      • (56:30-81:10) The acoustic oscillation at the last-scattering surface [10.1-10.4] 
    • Lecture 8 (PDF 12.8MB; last updated, November 26, 2020) [video (64 min)]
      • (0:00-50:08) Cosmological parameter dependence of the temperature power spectrum [10.5,10.6]
        • (31:35-40:55) The Hubble Constant Tension
      • (50:09-58:18) Basics of the CMB Polarisation [11]
      • (58:19-63:32) Stokes parameters [11.1]
    • Lecture 9 (PDF 14MB; last updated, January 11, 2022) [video is not available; the recording was lost due to the power failure in one of the server locations of GWDG. Too bad… Nevertheless, I hope that you can follow the lecture via the notes]
      • E- and B-mode polarisation [11.2.1]
      • E-mode from sound waves [11.4.1, 11.4.2, 11.5]
      • B-mode from gravitational lensing [11.6]
      • EB correlation: The cosmic birefringence [11.2.1]
        • For more information, see the video (40 min) of “Cosmology Talks” hosted by Dr. Shaun Hotchkiss at the University of Auckland.
    • Lecture 10 (PDF 15.7MB; last updated, November 29, 2020) [video (74 min)]
      • (0:00-18:50) Basics of the gravitational waves [5.1]
      • (18:51-32:10) Propagation of gravitational waves in an expanding universe [12.1]
      • (32:11-43:09) Temperature anisotropy from gravitational waves [12.2.1-12.2.3]
      • (43:10-64:16) E- and B-mode polarisation from gravitational waves [12.3.1]
      • (64:17-71:50) Experimental landscape [final chapter]
      • (71:51-74:11) The final remark
  • 講義スライド「原始重力波」
  • Lecture Slides: “Some tips for faculty, grant, and fellowship applications”
  • Lecture Slides: “Primordial Gravitational Waves from Inflation” [3 x 90 min]
    • University of Amsterdam; February 27, March 5 and 19, 2020
    • Lecture 1 (PDF 6.7MB; last updated, November 5, 2021) 
      • Primordial gravitational waves from the vacuum fluctuation
    • Lecture 2 (PDF 15.4MB; last updated, January 11, 2022) 
      • Polarisation of the cosmic microwave background
    • Lecture 3 (PDF 9MB; last updated, March 24, 2020) 
      • Primordial gravitational waves from the sourced contribution

2019

  • Lecture Slides: “Gravitational waves from the early Universe” [65 min]
    • Lecture at the “Frontier Research in Astrophysics and Particle Physics” seminar series for master students at Instituto de Física de Cantabria, Santander, Spain; June 4, 2019
    • GWlecture_santander.pdf (12.5MB; last updated, November 5, 2021) [video]

2018

  • Lecture Slides: “Physics of CMB Anisotropies” [3 x 90 min]
    • Cours d'automne du LAL, Laboratoire de l'Accélérateur Linéaire; October 15-17, 2018
    • Lecture 1 [video] (PDF 13.9MB; last updated, October 17, 2018) 
      • Brief introduction of the CMB research
      • Temperature anisotropy from gravitational effects
      • Power spectrum basics
    • Lecture 2 (PDF 8.4MB; last updated, October 17, 2018) 
    • [due to the absence of IT person at LAL on Oct 16, no video is available unfortunately]
      • Power spectrum of gravitational anisotropy
      • Temperature anistropy from sound waves
    • Lecture 3 [video] (PDF 11.6MB; last updated, October 17, 2018) 
      • Cosmological parameter dependence of the temperature power spectrum
      • Polarisation of the CMB
      • Gravitational waves and their imprints on the CMB
  • Lecture Slides: “Physics of CMB Anisotropies” [4 x 75 min]
    • Summer School on Cosmology 2018, ICTP, Trieste; June 18-21, 2018
    • Lecture 1 [video] (PDF 16.1MB; last updated, June 17, 2018)
      • Brief introduction of the CMB research
      • Temperature anisotropy from gravitational effects
      • Power spectrum basics
    • Lecture 2 [video] (PDF 6.5MB; last updated, June 17, 2018)
      • Temperature anistropy from sound waves
    • Lecture 3 [video] (PDF 6.4MB; last updated, June 17, 2018)
      • Cosmological parameter dependence of the temperature power spectrum
      • Polarisation of the CMB
    • Lecture 4 [video] (PDF 4MB; last updated, June 17, 2018)
      • Polarisation of the CMB [continued]
      • Gravitational waves and their imprints on the CMB

2017

  • Lecture Slides: “Physics of CMB Anisotropies” [5 x 45 min]
    • XIIIth School of Cosmology,  “The CMB from A to Z”, IESC, Cargèse; November 13-17, 2017
    • Lecture 1 (10.9MB; last updated, November 14, 2017)
      • Brief introduction of the CMB research
      • Temperature anisotropy from gravitational effects
    • Lecture 2 (7.9MB; last updated, November 14, 2017)
      • Power spectrum basics
      • Temperature anistropy from sound waves
    • Lecture 3 (2.8MB; last updated, November 14, 2017)
      • Temperature anistropy from sound waves [continued]
      • Cosmological parameter dependence of the temperature power spectrum
    • Lecture 4 (6.2MB; last updated, November 14, 2017)
      • Cosmological parameter dependence of the temperature power spectrum [continued]
      • Polarisation of the CMB
    • Lecture 5 (3.3MB; last updated, November 14, 2017)
      • Polarisation of the CMB [continued]
      • Gravitational waves and their imprints on the CMB

2014

2011

2010

2009

  • Lecture Note: "B-mode Polarization"
  • Lecture Note: "Primordial non-Gaussianity"
    • Department of Physics, Tohoku University; June 4, 2009
    • lecture_fnl.pdf (0.588MB)
  • Lecture Note: "B-mode Polarization and Primordial non-Gaussianity with Introduction"
    • Institute for the Physics and Mathematics of the Universe (IPMU); June 17, 2009
    • ipmu_lecture_2009.pdf (7.2MB)

2002

  • 集録「宇宙背景放射から何を学ぶか（個人的意見）」
    • Summer School on Astronomy and Astrophysics; August 1, 2002
    • ss02.pdf.zip (1.8MB) [zipped PDF]

2001

  • Ph.D. Thesis: "The Pursuit of Non-Gaussian Fluctuations in the Cosmic Microwave Background"

2000

  • 講義ノート「宇宙背景放射」 
  • 講義ノート「インフレーション理論のアウトライン」 

1999

  • 修士論文「宇宙背景放射」 
  • 修士論文・付録集「ゲージ不変な一般相対論的摂動論および光の伝播」 

1996

  • 天文学セミナー「宇宙論」 
    • February 14, 1996, Tohoku University, 37 pages. 
    • 東北大学理学部物理系学科天文学コース学部３年で行ったセミナー発表のノート．ノートをとっておいてくれた秋田谷洋氏に感謝します（April 20, 2017）
    • pdf
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