The workshop will focus on the uses of the topological tools known as spectrum to understand the representation theory of algebras. This includes the Balmer, Cohn, Gabriel, Gelfand, maximal, Pierce, primitive, projective, punctured, Stone, triangulated, Zariski, and Ziegler spectrums, just to name a few. The workshop aims to provide a friendly introduction to some of these topics for newcomers, as well as to be a platform to discuss recent developments and interconnections.

The workshop is comprised of a minicourse, six invited talks, nine contributed talks, and three lightning talks. Junior researchers, postdoctoral scholars, and graduate students, are particularly encouraged to apply to give a talk. We especially welcome applications from women and minority groups in mathematics.

The workshop will be held on

• 16-19 December 2025.

The workshop will be held in a hybrid format, the physical venue being

• Rooms E408 and F415,
• Building E,
• Faculty of Science,
• Sugimoto Campus,
• Osaka Metropolitan University.

The minicourse instructor follows.

• Ryo Takahashi (Nagoya University)

The confirmed speakers follow.

• Lidia Angeleri Hügel (University of Verona) *
• Paul Balmer (University of California, Los Angeles)
• Abhishek Banerjee (Indian Institute of Science)
• Anish Chedalavada (Johns Hopkins University)
• Fatemeh Esmaeelzadeh (Islamic Azad University, Bojnourd)
• Osamu Iyama (The University of Tokyo)
• Giovanna Le Gros (Charles University, Prague)
• Hiroki Matsui (Tokushima University)
• Hisato Matsukawa (Hokkaido University)
• Sam Miller (University of Georgia)
• So Nakamura (University of California, Irvine)
• Tsutomu Nakamura (Kyoto University of Education)
• Luca Pol (Max Planck Institute for Mathematics, Bonn)
• Manuel Reyes (University of California, Irvine)
• Ariel Rosenfield (University of Maryland, College Park)
• Shunya Saito (The University of Tokyo)
• Julia Semikina (University of Lille)

* Online speaker.

Registrations, applications for financial support, and submissions of contributed talks are now closed.

The workshop deadlines follow.

• 1 September at 23:59 JST - Apply for financial support
• 1 September at 23:59 JST - Submit a contributed talk
• 1 November at 23:59 JST - Register for in-person participation
• 1 December at 23:59 JST - Register for online participation

We strongly encourage international participants arrive in Osaka on December 15 and depart Osaka on December 20. This avoids any potential issues or conflicts that may otherwise arise.

This is an overview of the schedule for the workshop.

	December 16	December 17	December 18		December 19
9:30	opening
10:00	R. Takahashi 1	R. Takahashi 2	R. Takahashi 3	10:00	S. Miller
11:15	break	break	break	11:00	break
11:40	P. Balmer	O. Iyama	M. Reyes	11:15	G. Le Gros
12:40	lunch	lunch	lunch	12:15	break
14:30	H. Matsui	H. Matsukawa	A. Rosenfield	12:30	T. Nakamura
15:30	break	break	break	13:45	closing
15:50	A. Chedalavada	L. Pol	S. Nakamura
16:50	break	break	break
17:10	S. Saito	L. Angeleri Hügel	Short Talks
18:30			banquet

Here is the detailed schedule with titles and abstracts. Talks will be in room E408. The breaks will be in room F415. The banquet will be at the restaurant Metasequoia.

The venue is the Faculty of Science of the Osaka Metropolitan University.

Here is some additional local information.

The workshop is supported by JSPS KAKENHI Grant-in-Aid for Scientific Research (S), Number JP21H04994, Principal Investigator Atsushi Takahashi.

The workshop is supported by JSPS KAKENHI Grant-in-Aid for Scientific Research (C), Number JP24K06693, Principal Investigator Ryo Kanda.

The workshop is supported by JSPS KAKENHI Grant-in-Aid for Early-Career Scientists, Number JP24K16908, Principal Investigator Kaveh Mousavand.

The workshop is supported by JSPS KAKENHI Grant-in-Aid for Early-Career Scientists, Number JP25K17242, Principal Investigator Pablo S. Ocal.

The organizers would like to acknowledge support of the Osaka Central Advanced Mathematical Institute at Osaka Metropolitan University through the MEXT Promotion of Distinctive Joint Research Center Program JPMXP0723833165.

The organizers would like to acknowledge support of the Osaka Central Advanced Mathematical Institute at Osaka Metropolitan University through the Osaka Metropolitan University Strategic Research Promotion Project: Development of International Research Hubs.

The organizers would like to acknowledge support of the UK-European Representation Theory and Categorification Network through EPSRC grant UKRI1721.

The organizers would like to acknowledge support of the University of Lille.

The organizers would also like to thank Luca Pol, Manuel Reyes, and Shunya Saito for their help chairing sessions.