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Purpose

In 2016, LIGO confirmed the existence of gravitational waves, and in 2023, a pulsar timing array, NANOGrav, reported a gravitational wave background signal. Gravitational waves are becoming a useful tool to explore the early universe and even fundamental physics. A variety of ways to detect gravitational waves are ongoing and proposed, covering a vast range of gravitational wave frequency bands.

One of the observable gravitational wave sources is a phase transition in the early universe, leading to bubbles and/or topological defects. Axion, one of the dark matter candidates, also predicts composite topological defects. Therefore, now will be a high time to understand the basic properties of topological solitons originating in fundamental physics. Topological solitons are also important in low-energy physics such as superconducters.

Our purpose of this workshop is to share and discuss recent progress and new ideas on frontiers in gravity and fundamental physics and to trigger the interplay between fundamental physicists and cosmologists.

This workshop is hybrid. We broadcast the workshop via Zoom to online participants.
All the talks in this workshop are given in English. The time zone is JST (UTC+9).

Keywords

Keywords:

• dark matter,
• axions,
• phase transitions,
• solitons, (including topological defects, Q-balls, oscillons,)
• gravitational waves.

Invited Speakers

• Elisa Ferreira (Kavli IPMU)

• Junseok Lee (Tohoku University)

• Wakutaka Nakano (KEK)

• Nobuchika Okada (University of Alabama, Online)

• Takashi Toma (Kanazawa University)

• Graham White (University of Southampton, Online)

Speakers

• Gonzalo Alonso-Alvarez (University of Toronto, Online)

• Takumi Fujimori (Osaka Metropolitan University)

• Katsuya Hashino (NIT, Fukushima College)

• Asuka Ito (Kobe University)

• Ryusuke Jinno (Kobe University)

• Maria Mylova (Kavli IPMU)

• Ippei Obata (Kavli IPMU)

• Jan Tränkle (ITP Leibniz University Hannover)

• Lukas Treuer (KEK, The Graduate U. Adv. Studies (SOKENDAI))

Timetable

Photo

Registration

Important Notices

On-site participants need to pay the following in cash (JPY) on your arrival:

• Participation Fee: 1,000JPY
• (if you join the banquet) Banquet Fee: 6,000JPY
• (if you made a reservation in advance) Lunch box: 1,000JPY/day

Important Dates

Abstract Submission Deadline (for both on-site and online contributed talks): Closed

Registration deadline for on-site participants: Closed

Registration deadline for online participants: 15th February, 2025

Schedule

From 4th to 5th of March, 2025

The first talk starts at 10:00 (JST) on the first day. The final talk ends at 16:00 (JST) on the second day.

We have

• invited talks (50min + 10min for each)
• contributed talks (15min + 5min for each)

Venue

Seminar Room 1 and 2, 4th building, Faculty of Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, 992-8510, Yamagata

• 8min from Yonezawa Station by taxi
  • Yonezawa Station (130min from Tokyo Station, 70min from Sendai Station by Shinkansen)
• 10min from Minami-Yonezawa Station on foot
  • Minami-Yonezawa Station (6min from Yonezawa Station by Yonesaka line)
• 12min from Uesugi Jinja Mae Bus Stop on foot
  • Uesugi Jinja Mae Bus Stop (2 hours from Sendai Station by highway bus)

Banquet

Shoutouen

• 15min from the venue on foot
• Kaiseki-ryori (a traditional Japanese-style cuisine) with a few kinds of local Japanese sake

Introduction of Yonezawa

Yonezawa has a long history and is famous for being the land ruled by the Date and Uesugi families. Uesugi Shrine, Uesugi Clan Mausoleum, and Kasuga-san Rinsen-ji, the family temple of the Uesugi, are located here. The main building of Yonezawa Higher Technical School, the predecessor of Yamagata University’s Faculty of Engineering, still exists in Yamagata University. The Okitama (or some call “Oitama”) region, centered on Yonezawa, has many hot springs, including Onogawa Onsen, Shirabu Onsen, and Akayu Onsen.

For more information on Yonezawa, please visit, e.g., Travel Yonezawa.

Information

• Hotels:
  • Den’s Hotel Yonezawa (5min by taxi from the campus)
  • Hotel Alpha-1 Yonezawa (5min on foot from the Yonezawa station)
  • Hotel Route Inn Yonezawa (10min on foot from the Yonezawa station)
• Local Buses:
  • City circulation line (clockwise) (Get off at Yamadai-Seimon, Japanese version)
  • Gakuen-Toshi Line (Get off at Johnan-Nichome, Japanese version )

Previous workshops

This is the second workshop on Frontiers in Gravity and Fundamental Physics.

Frontiers in Gravity and Fundamental Physics (YU Workshop 2022)

Organizers

• Masato Arai (Yamagata University)

• Minoru Eto (Yamagata University)

• Asuka Ito (Kobe University)

• Ryusuke Jinno (Kobe University)

• Ippei Obata (Kavli IPMU)

• Yuki Sakakihara (Yamagata University, Chief organizer)

Contact us

Secretary

• Emiko Okatsu (Yamagata University)

Sponsors

This workshop is supported by the following KAKENHI and Graduate School of Science and Engineering, Yamagata University.

• Grant-in-Aid for Scientific Research (C)
  • 24K07013 for Ryusuke Jinno (PI)
• Grant-in-Aid for Research Activity Start-up
  • 23K19048 for Ryusuke Jinno (PI)
  • 22K20365 for Yuki Sakakihara (PI)
• Grant-in-Aid for Early-Career Scientists
  • 22K14034 for Asuka Ito (PI)
  • 19K14702 for Ippei Obata (PI)
• Grant-in-Aid for Exploratory Research
  • 23K17687 for Ryusuke Jinno (co-PI)
• Grant-in-Aid for Scientific Research (B)
  • 22H01221 for Minoru Eto (co-PI)

The venue and facilities are provided by Graduate School of Science and Engineering, Yamagata University.