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Inflationary universe in light of stochastic calculus, primordial black holes, and gravitational waves

Research Project

Project/Area Number 21K13918
Research Category

Grant-in-Aid for Early-Career Scientists

Allocation TypeMulti-year Fund
Review Section Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
Research InstitutionNagoya University

Principal Investigator

Tada Yuichiro  名古屋大学, 高等研究院(理), 特任助教 (90837022)

Project Period (FY) 2021-04-01 – 2024-03-31
Project Status Completed (Fiscal Year 2023)
Budget Amount *help
¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000)
Fiscal Year 2023: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Fiscal Year 2022: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2021: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Keywordsインフレーション / 確率形式 / 原始ブラックホール / 重力波 / 宇宙論
Outline of Research at the Start

本研究の目的を踏まえ具体的研究課題は次のように3つに分けられる. 1つ目はインフレーションの確率形式を理論的に整備するとともに, 数値計算プログラムを開発・公開し, さらに具体的なインフレーション理論の解析を行うことである. また本形式を応用し原始ブラックホール形成理論を探るとともに, 正確な原始ブラックホール量の計算法を確立する. そして原始ブラックホールに関連した初期重力波を通じてインフレーションに対して得られる情報を模索する.

Outline of Final Research Achievements

This research aimed to elucidate the mechanism of the inflationary universe from three perspectives: stochastic formalism, primordial black holes (PBHs), and gravitational waves (GWs). We have written a total of 16 original papers funded by this grant, and established methods for coarse-graining observable fields in stochastic formalism, estimating the PBH abundance from non-Gaussian initial fluctuations, and estimating the GW abundance in such cases. In recognition of these achievements, we are invited to contribute a chapter to the book "Black Holes in the Era of Gravitational-Wave Astronomy" and wrote the summary paper arXiv:2211.05767 on PBH together with Dr Escriva and Dr Kuhnel.

Academic Significance and Societal Importance of the Research Achievements

宇宙に満ちる暗黒物質の正体が未だ不明な中、その候補として原始 BH が注目を集めている。小惑星程度の質量の原始 BH であればこれまでの観測と矛盾なく暗黒物質を説明できる一方、その証拠を観測的に得ることは難しい。そこで副産物である重力波が間接的証拠として注目され、将来の宇宙望遠鏡 LISA で観測可能であることが示されている。本研究により原始 BH 量と重力波量のより定量的な関係性が明らかになり、実際に重力波が観測された際に原始 BH の間接的証拠としての根拠が強くなるとともに、インフレーション宇宙への示唆を得ることもできるようになった。

Report

(4 results)
  • 2023 Annual Research Report   Final Research Report ( PDF )
  • 2022 Research-status Report
  • 2021 Research-status Report
  • Research Products

    (57 results)

All 2024 2023 2022 2021 Other

All Int'l Joint Research (4 results) Journal Article (18 results) (of which Int'l Joint Research: 2 results,  Peer Reviewed: 16 results,  Open Access: 5 results) Presentation (28 results) (of which Int'l Joint Research: 18 results,  Invited: 8 results) Remarks (7 results)

  • [Int'l Joint Research] Universite Libre de Bruxelles(ベルギー)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] Ludwig-Maximilians-Universitat/Max-Planck-Institut fur Physik(ドイツ)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] Institut d’Astrophysique de Paris/Laboratoire Astroparticule et Cosmologie(フランス)

    • Related Report
      2021 Research-status Report
  • [Int'l Joint Research] Universite Libre de Bruxelles(ベルギー)

    • Related Report
      2021 Research-status Report
  • [Journal Article] Cancellation of quantum corrections on the soft curvature perturbations2024

    • Author(s)
      Tada Yuichiro、Terada Takahiro、Tokuda Junsei
    • Journal Title

      Journal of High Energy Physics

      Volume: 2024 Issue: 1

    • DOI

      10.1007/jhep01(2024)105

    • Related Report
      2023 Annual Research Report
  • [Journal Article] Translating nano-Hertz gravitational wave background into primordial perturbations taking account of the cosmological QCD phase transition2023

    • Author(s)
      Abe Katsuya T.、Tada Yuichiro
    • Journal Title

      Physical Review D

      Volume: 108 Issue: 10

    • DOI

      10.1103/physrevd.108.l101304

    • Related Report
      2023 Annual Research Report
  • [Journal Article] Stochastic dynamics of multi-waterfall hybrid inflation and formation of primordial black holes2023

    • Author(s)
      Tada Yuichiro、Yamada Masaki
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2023 Issue: 11 Pages: 089-089

    • DOI

      10.1088/1475-7516/2023/11/089

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Primordial black hole formation in hybrid inflation2023

    • Author(s)
      Tada Yuichiro、Yamada Masaki
    • Journal Title

      Physical Review D

      Volume: 107 Issue: 12 Pages: 12-123539

    • DOI

      10.1103/physrevd.107.123539

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Squeezed bispectrum and one-loop corrections in transient constant-roll inflation2023

    • Author(s)
      Motohashi Hayato、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2023 Issue: 08 Pages: 069-069

    • DOI

      10.1088/1475-7516/2023/08/069

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Primordial black holes and gravitational waves induced by exponential-tailed perturbations2023

    • Author(s)
      Abe Katsuya T.、Inui Ryoto、Tada Yuichiro、Yokoyama Shuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2023 Issue: 05 Pages: 044-044

    • DOI

      10.1088/1475-7516/2023/05/044

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Hybrid metric-Palatini Higgs inflation2023

    • Author(s)
      He Minxi、Mikura Yusuke、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2023 Issue: 05 Pages: 047-047

    • DOI

      10.1088/1475-7516/2023/05/047

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Effective Inspiral Spin Distribution of Primordial Black Hole Binaries2022

    • Author(s)
      Koga Yasutaka、Harada Tomohiro、Tada Yuichiro、Yokoyama Shuichiro、Yoo Chul-Moon
    • Journal Title

      The Astrophysical Journal

      Volume: 939 Issue: 2 Pages: 65-65

    • DOI

      10.3847/1538-4357/ac93f1

    • Related Report
      2022 Research-status Report
    • Peer Reviewed / Open Access
  • [Journal Article] Stochastic formalism for U(1) gauge fields in axion inflation2022

    • Author(s)
      Fujita Tomohiro、Mukaida Kyohei、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2022 Issue: 12 Pages: 026-026

    • DOI

      10.1088/1475-7516/2022/12/026

    • Related Report
      2022 Research-status Report
    • Peer Reviewed
  • [Journal Article] Effective treatment of U(1) gauge field and charged particles in axion inflation2022

    • Author(s)
      Fujita Tomohiro、Kume Jun'ya、Mukaida Kyohei、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2022 Issue: 09 Pages: 023-023

    • DOI

      10.1088/1475-7516/2022/09/023

    • Related Report
      2022 Research-status Report
    • Peer Reviewed
  • [Journal Article] Simulation of primordial black holes with large negative non-Gaussianity2022

    • Author(s)
      Escriva Albert、Tada Yuichiro、Yokoyama Shuichiro、Yoo Chul-Moon
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2022 Issue: 05 Pages: 012-012

    • DOI

      10.1088/1475-7516/2022/05/012

    • Related Report
      2022 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] On UV-completion of Palatini-Higgs inflation2022

    • Author(s)
      Mikura Yusuke、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2022 Issue: 05 Pages: 035-035

    • DOI

      10.1088/1475-7516/2022/05/035

    • Related Report
      2022 Research-status Report
    • Peer Reviewed
  • [Journal Article] Statistics of coarse-grained cosmological fields in stochastic inflation2022

    • Author(s)
      Tada Yuichiro、Vennin Vincent
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2022 Issue: 02 Pages: 021-021

    • DOI

      10.1088/1475-7516/2022/02/021

    • Related Report
      2021 Research-status Report
    • Peer Reviewed
  • [Journal Article] A manifestly covariant theory of multifield stochastic inflation in phase space: solving the discretisation ambiguity in stochastic inflation2021

    • Author(s)
      Pinol Lucas、Renaux-Petel S?bastien、Tada Yuichiro
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2021 Issue: 04 Pages: 048-048

    • DOI

      10.1088/1475-7516/2021/04/048

    • Related Report
      2021 Research-status Report
    • Peer Reviewed
  • [Journal Article] Induced gravitational waves as a cosmological probe of the sound speed during the QCD phase transition2021

    • Author(s)
      Abe Katsuya T.、Tada Yuichiro、Ueda Ikumi
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2021 Issue: 06 Pages: 048-048

    • DOI

      10.1088/1475-7516/2021/06/048

    • Related Report
      2021 Research-status Report
    • Peer Reviewed
  • [Journal Article] Revisiting non-Gaussianity in non-attractor inflation models in the light of the cosmological soft theorem2021

    • Author(s)
      Suyama Teruaki、Tada Yuichiro、Yamaguchi Masahide
    • Journal Title

      Progress of Theoretical and Experimental Physics

      Volume: 2021 Pages: 1-20

    • DOI

      10.1093/ptep/ptab063

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Open Access
  • [Journal Article] Minimal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>k</mml:mi></mml:math>-inflation in light of the conformal metric-affine geometry2021

    • Author(s)
      Mikura Yusuke、Tada Yuichiro、Yokoyama Shuichiro
    • Journal Title

      Physical Review D

      Volume: 103 Issue: 10 Pages: 1-1

    • DOI

      10.1103/physrevd.103.l101303

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Open Access
  • [Journal Article] Primordial black holes in peak theory with a non-Gaussian tail2021

    • Author(s)
      Kitajima Naoya、Tada Yuichiro、Yokoyama Shuichiro、Yoo Chul-Moon
    • Journal Title

      Journal of Cosmology and Astroparticle Physics

      Volume: 2021 Issue: 10 Pages: 053-053

    • DOI

      10.1088/1475-7516/2021/10/053

    • Related Report
      2021 Research-status Report
    • Peer Reviewed
  • [Presentation] Dive into the Cosmic Abyss: Echoes from Primordial Black Hole2024

    • Author(s)
      Y. Tada
    • Organizer
      Joint workshop on General Relativity and Cosmology
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Cancellation of quantum corrections on the soft curvature perturbations2024

    • Author(s)
      Y. Tada, T. Terada, J. Tokuda
    • Organizer
      YITP long-term workshop "Gravity and Cosmology 2024"
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] インフレーションと超準解析 --- 原始ブラックホールに向けて ---2024

    • Author(s)
      多田祐一郎
    • Organizer
      "Physics meets Mathematics" まとめ合宿
    • Related Report
      2023 Annual Research Report
  • [Presentation] The present and future of primordial black holes as dark matter2023

    • Author(s)
      Y. Tada
    • Organizer
      The 32nd Texas Symposium on Relativistic Astrophysics
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] The present and future of primordial black holes as dark matter2023

    • Author(s)
      Y. Tada
    • Organizer
      KASHIWA DARK MATTER SYMPOSIUM 2023
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Cancellation of quantum corrections on the soft curvature perturbations2023

    • Author(s)
      Y. Tada, T. Terada, J. Tokuda
    • Organizer
      JGRG 32
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Squeezed bispectrum and one-loop corrections in transient constant-roll inflation2023

    • Author(s)
      H. Motohashi, Y. Tada, T. Terada, J. Tokuda
    • Organizer
      COSMO'23
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Stochastic approach to the inflationary universe2023

    • Author(s)
      Y. Tada
    • Organizer
      YITP International Molecule-type Workshop "Revisiting cosmological non-linearities in the era of precision surveys"
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Statistics of coarse-grained cosmological fields in stochastic inflation2023

    • Author(s)
      Y. Tada and V. Vennin
    • Organizer
      New Horizons in Primordial Black Hole Physics
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Revisiting the formation of massive primordial black holes in hybrid inflation2023

    • Author(s)
      Y. Tada and M. Yamada
    • Organizer
      i-LINK workshop on observational cosmology
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 原始ブラックホールは自然科学なのか2023

    • Author(s)
      多田祐一郎
    • Organizer
      基研研究会 素粒子物理学の進展2023 (PPP2023)
    • Related Report
      2023 Annual Research Report
    • Invited
  • [Presentation] On the soft theorem in the transient ultra-slow or constant roll inflation2023

    • Author(s)
      H. Motohashi and Y. Tada
    • Organizer
      Domestic Molecule-type Workshop "Non-linear Nature of Cosmological Perturbations and its Observational Consequences"
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research
  • [Presentation] Inflation theory --- D'ou venons-nous? Que sommes-nous? Ou allons-nous? ---2023

    • Author(s)
      Y. Tada
    • Organizer
      19th Rencontres du Vietnam "Theory meeting experiments: particle astrophysics and cosmology"
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research
  • [Presentation] 多重滝場ハイブリッドインフレーションと原始ブラックホール2023

    • Author(s)
      多田祐一郎, 山田將樹
    • Organizer
      日本物理学会第77回年次大会
    • Related Report
      2022 Research-status Report
  • [Presentation] Stochastic approach to cosmic inflation2022

    • Author(s)
      Y. Tada
    • Organizer
      TSQS 2022
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research
  • [Presentation] Hybrid metric-Palatini Higgs inflation2022

    • Author(s)
      M. He, Y. Mikura, and Y. Tada
    • Organizer
      JGRG31
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research
  • [Presentation] 原始ブラックホール研究の近年の進展2022

    • Author(s)
      多田祐一郎
    • Organizer
      第35回 理論懇シンポジウム
    • Related Report
      2022 Research-status Report
  • [Presentation] 曲率ゆらぎへの非摂動的アプローチ2022

    • Author(s)
      多田祐一郎
    • Organizer
      第11回観測的宇宙論ワークショップ
    • Related Report
      2022 Research-status Report
    • Invited
  • [Presentation] Recent progress on stochastic inflation2022

    • Author(s)
      多田祐一郎
    • Organizer
      Workshop on Gravitation & Cosmology
    • Related Report
      2022 Research-status Report
  • [Presentation] アクシオンインフレーションにおける U(1) ゲージ場の確率形式2022

    • Author(s)
      藤田智弘, 向田享平, 多田祐一郎
    • Organizer
      日本物理学会秋季大会
    • Related Report
      2022 Research-status Report
  • [Presentation] Primordial black holes and induced gravitational waves in light of the non-Gaussian tail2022

    • Author(s)
      Yuichiro Tada
    • Organizer
      FY2021 学術変革領域研究「ダークマター」シンポジウム
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] 原始ブラックホールのピーク理論と非ガウス尾2022

    • Author(s)
      多田祐一郎
    • Organizer
      日本物理学会第77回年次大会
    • Related Report
      2021 Research-status Report
  • [Presentation] Primordial black holes in peak theory with a non-Gaussian tail2021

    • Author(s)
      Yuichiro Tada
    • Organizer
      2021 NRF-JSPS Workshop in particle physics, cosmology, and gravitation
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Probability density functions of coarse-grained curvature and density perturbations in stochastic inflation2021

    • Author(s)
      Yuichiro Tada
    • Organizer
      COSMO'21
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research
  • [Presentation] Primordial black holes in peak theory with a non-Gaussian tail2021

    • Author(s)
      Yuichiro Tada
    • Organizer
      The KEK-PH + KEK-Cosmo joint workshop on "Primordial Black Holes"
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research
  • [Presentation] Probability density functions of coarse-grained curvature and density perturbations in stochastic inflation2021

    • Author(s)
      Yuichiro Tada
    • Organizer
      JGRG30
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research
  • [Presentation] 粗視化曲率ゆらぎの確率密度関数2021

    • Author(s)
      多田祐一郎
    • Organizer
      日本物理学会秋季大会
    • Related Report
      2021 Research-status Report
  • [Presentation] インフレーションの「現在」と重力波2021

    • Author(s)
      多田祐一郎
    • Organizer
      DECIGO workshop
    • Related Report
      2021 Research-status Report
    • Invited
  • [Remarks]

    • URL

      https://nekomammat.github.io/indexJP.html

    • Related Report
      2023 Annual Research Report
  • [Remarks]

    • URL

      https://profs.provost.nagoya-u.ac.jp/html/100011770_ja.html

    • Related Report
      2023 Annual Research Report
  • [Remarks]

    • URL

      https://github.com/STOchasticLAtticeSimulation

    • Related Report
      2023 Annual Research Report
  • [Remarks]

    • URL

      https://profs.provost.nagoya-u.ac.jp/html/100011770_ja.html?k=%E5%A4%9A%E7%94%B0%E7%A5%90%E4%B8%80%E9%83%8E

    • Related Report
      2022 Research-status Report
  • [Remarks]

    • URL

      https://nekomammat.github.io/indexJP.html

    • Related Report
      2022 Research-status Report
  • [Remarks]

    • URL

      https://profs.provost.nagoya-u.ac.jp/html/100011770_ja.html?k=%E5%A4%9A%E7%94%B0%E7%A5%90%E4%B8%80%E9%83%8E

    • Related Report
      2021 Research-status Report
  • [Remarks]

    • URL

      https://nekomammat.github.io/indexJP.html

    • Related Report
      2021 Research-status Report

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Published: 2021-04-28   Modified: 2025-01-30  

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