Yonsei Lab for Dark Universe Special Lectures - Higgs Inflation

5 Aug 2020, 16:00 → 7 Aug 2020, 17:30 Asia/Seoul

For those with any questions regarding the registration, please send an email to dhongyeon@yonsei.ac.kr 

Title: Yonsei Lab for Dark Universe special lectures, Kohei Kamda

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Introduction

Primordial inflation is now a part of modern cosmology since it elegantly solves several problems in the standard Big Bang cosmology simultaneously. However, the physics that drives inflation is yet far from understood. In light of the discovery of the Higgs particle at the Large Hadron Collider, the first task for cosmologists and particle phenomenologists is to investigate the possibility that the Standard Model Higgs is responsible for inflation. In this lecture, I will introduce the idea of the oirignal Higgs inflation and explain its inherent problems. Then I explain how the extension with R^2 term is a reasonable and promising one and how it is consistent with the original motivation for the investigation to the Higgs inflation. Finally I will introduce recent studies on the cosmological consequences on this extension and discuss future directions. 

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Schedule

Lecture #1 16:00-17:30 (Seoul/Tokyo) Aug 5, 2020

"Introduction to the pure Higgs inflation". 
In the first lecture, I will introduce the basics of the Higgs inflation with the non-minimal coupling to gravity, \xi H^2 R term. Then I explain its cosmological consequences and addresses the problems in the model, such as the Higgs vacuum stability and the unitarity problem. 

Refs. 
[1] B.L.Spokoiny, Phys. Lett. B147 (1984) 39
[2] J.L.Cervantes-Cota and H.Dehnen, Nucl. Phys. B 442, 391 (1995); F.Bezrukov and M.Shaposhnikov, Phys. Lett. B 659 (2008) 703
[3] F.Bezrukov, J.Rubio, and M.Shaposhnikov, Phys. Rev. D 92 no. 8, (2015) 083512,
[4] F.Bezrukov, A.Magnin, M.Shaposhnikov and S.Sibiryakov, JHEP 1101 (2011) 016
[5] Y.Ema, R.Jinno, K.Mukaida, and K.Nakayama, JCAP 02 (2017) 045; M.P.DeCross, D.I.Kaiser, A.Prabhu, C.Prescod-Weinstein, and E.I.Sfakianakis, Phys. Rev. D 97 no. 2, (2018) 023526,

 

Lecture #2 16:00-17:30 (Seoul/Tokyo) Aug 6, 2020

"Mixed Higgs-R^2 model as a UV-extension of the pure Higgs inflation"
In the second lecture, I will explain how the unitarity problem in the Higgs inflation is resolved by adding the R^2 term. I will also explain why we can say it is the most natural and inevitable extension of the Higgs inflation from the point of view of the renormlaization group approach. Then I will show the dynamics of the model during inflation.

Refs.
[1] Y.Ema, Phys. Lett. B 770 (2017) 403
[2] M.He, A.A.Starobinsky, and J.Yokoyama, JCAP 05 (2018) 064
[3] D.Gorbunov and A.Tokareva, Phys. Lett. B 788 (2019) 37
[4] Y.Ema, JCAP 09 (2019) 027; Y.Ema, K.Mukaida, and J.van de Vis, arXiv:2002.11739 [hep-ph].

 

Lecture #3 16:00-17:30 (Seoul/Tokyo) Aug 7, 2020

"Towards the understanding on the reheating in the Mixed Higgs-R^2 model"
In the final lecture, I will discuss the dynamics of the model after inflation, that is, the reheating process, which is important to identify the model against the cosmological observations. This process is still being investigated and we have not obtained the complete picture. I will argue the future directions in the study of the Higgs inflation. 

Refs. 
[1] M.He, R.Jinno, K.Kamada, S.C.Park, A.A.Starobinsky, and J.Yokoyama, Phys. Lett. B 791 (2019) 36
[2] F.Bezrukov, D.Gorbunov, C.Shepherd, and A.Tokareva, Phys. Lett. B 795 (2019) 657
[3] M.He, R.Jinno, K.Kamada, A.A.Starobinsky, and J.Yokoyama, 2007.10369 [hep-ph]
[4] F.Bezrukov, and C.Shepherd, 2007.10978 [hep-ph]

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Zoom address
https://yonsei.zoom.us/j/94227061413?pwd=ek5JRXE2cjRDanJLTzJLS0ZBaDNEZz09
 

ID: 942 2706 1413

PW: 544809
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Note : Lecture materials are planned to be sent to registered participants exclusively. Please register in order to receive the relevant course materials. 

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Wednesday, 5 August

16:00 → 17:30 Introduction to the pure Higgs inflation: Lecture #1

In the first lecture, I will introduce the basics of the Higgs inflation with the non-minimal coupling to gravity, \xi H^2 R term. Then I explain its cosmological consequences and addresses the problems in the model, such as the Higgs vacuum stability and the unitarity problem.
Refs.
[1] B.L.Spokoiny, Phys. Lett. B147 (1984) 39
[2] J.L.Cervantes-Cota and H.Dehnen, Nucl. Phys. B 442, 391 (1995); F.Bezrukov and M.Shaposhnikov, Phys. Lett. B 659 (2008) 703
[3] F.Bezrukov, J.Rubio, and M.Shaposhnikov, Phys. Rev. D 92 no. 8, (2015) 083512,
[4] F.Bezrukov, A.Magnin, M.Shaposhnikov and S.Sibiryakov, JHEP 1101 (2011) 016
[5] Y.Ema, R.Jinno, K.Mukaida, and K.Nakayama, JCAP 02 (2017) 045; M.P.DeCross, D.I.Kaiser, A.Prabhu, C.Prescod-Weinstein, and E.I.Sfakianakis, Phys. Rev. D 97 no. 2, (2018) 023526,

Convener: Prof. Kohei Kamada (University of Tokyo)

Thursday, 6 August

16:00 → 17:30 Mixed Higgs-R^2 model as a UV-extension of the pure Higgs inflation: Lecture #2

In the second lecture, I will explain how the unitarity problem in the Higgs inflation is resolved by adding the R^2 term. I will also explain why we can say it is the most natural and inevitable extension of the Higgs inflation from the point of view of the renormlaization group approach. Then I will show the dynamics of the model during inflation.
Refs.
[1] Y.Ema, Phys. Lett. B 770 (2017) 403
[2] M.He, A.A.Starobinsky, and J.Yokoyama, JCAP 05 (2018) 064
[3] D.Gorbunov and A.Tokareva, Phys. Lett. B 788 (2019) 37
[4] Y.Ema, JCAP 09 (2019) 027; Y.Ema, K.Mukaida, and J.van de Vis, arXiv:2002.11739 [hep-ph].

Convener: Prof. Kohei Kamada (University of Tokyo)

Friday, 7 August

16:00 → 17:30 Towards the understanding on the reheating in the Mixed Higgs-R^2 model: Lecture #3

In the final lecture, I will discuss the dynamics of the model after inflation, that is, the reheating process, which is important to identify the model against the cosmological observations. This process is still being investigated and we have not obtained the complete picture. I will argue the future directions in the study of the Higgs inflation.
Refs.
[1] M.He, R.Jinno, K.Kamada, S.C.Park, A.A.Starobinsky, and J.Yokoyama, Phys. Lett. B 791 (2019) 36
[2] F.Bezrukov, D.Gorbunov, C.Shepherd, and A.Tokareva, Phys. Lett. B 795 (2019) 657
[3] M.He, R.Jinno, K.Kamada, A.A.Starobinsky, and J.Yokoyama, 2007.10369 [hep-ph]
[4] F.Bezrukov, and C.Shepherd, 2007.10978 [hep-ph]

Convener: Prof. Kohei Kamada (University of Tokyo)