# North British Semigroups and Applications Network

NBSAN is a network of researchers in Scotland and Northern England with interests in semigroup theory and its applications. It is funded chiefly by a grant from the London Mathematical Society, with additional contributions from host departments and occasionally from other sources. It holds two meetings per year in different locations around the region, plus occasional online activities. The main participant universities are East Anglia, Manchester, St Andrews and York, but our activities are open to all interested researchers. Attendance at all meetings is free. We especially welcome graduate students.

For enquiries about individual meetings, please contact the relevant local organiser as described below. To enquire about the network please contact the central coordinator Nóra Szakács. To join the mailing list please contact Mark Kambites.

## Next Meeting

The next NBSAN meeting will be held in **Manchester** on **Thursday 20th and Friday 21st June 2024**,
as a satellite to the 75th British
Mathematical Colloquium held **between 17th and 20th June**. The
BMC itself will
feature lots of semigroups content, and we expect the conjunction of the
two events to attract a significant international semigroups audience
for the week. The semigroup programme is organised by Marianne Johnson,
Mark Kambites, Dmitry Kudryavtsev, Alex Levine and Nóra Szakács.

**Wednesday**evening (note that this is a different day to previously advertised). NBSAN runs from lunchtime on Thursday until 16:30 on Friday, with a dinner (paid separately) on Thursday evening. On Saturday, for those able to stay, there will be an unofficial social excursion (paid separately, provisionally to Quarry Bank Mill, an industrial heritage site with a working 18th century cotton mill and picturesque gardens).

**Semigroups in the BMC Programme.** The semigroups content of the BMC will be spread over the duration of the meeting, and
will feature:

- a morning talk by Robert D. Gray on
*The geometry of the word problem for groups and inverse monoids*; - invited workshop talks by Peter Cameron, Victoria Gould, Marianne Johnson, Stuart Margolis, Yann Peresse and Nik Ruškuc; and
- contributed speed talks by Ádám Budai, Reinis Cirpons, Matthias Fresacher, Martin Hampenberg Christensen, Daniel Heath, Jung Won Cho, Ajda Lemut, Carl-Fredrik Nyberg Brodda, Duarte Ribeiro and Jonathan Warne.

### NBSAN on Thursday 20th June

- 14:00 - António Malheiro -
*Quasi-crystals and algebraic structures: linking cyrstal bases to semigroups and beyond*( abstract ) - 15:00 - Thomas Aird -
*The meet-stalactic and meet-taiga monoid*( abstract ) - 15:30 - Magdalena Wiertel -
*Hecke-Kiselman monoids and algebras*( abstract ) - 16:00 - Coffee break
- 16:30 - Igor Dolinka -
*Prefix monoids of groups and right units of special inverse monoids*( abstract ) - 17:30 - Towards Dinner....

### NBSAN on Friday 21st June

- 09:00 - Ganna Kudryavtseva -
*Duality theory for Boolean right restriction semigroups*( abstract ) - 10:00 - Itamar Stein -
*The algebra of the monoid of order-preserving functions and other reduced E-Fountain semigroups*( abstract ) - 10:30 - Coffee break
- 11:00 - Luna Elliott -
*E-disjunctive inverse semigroups*( abstract ) - 11:30 - Herman Goulet-Ouellet -
*Profinite bridges between semigroup theory and symbolic dynamics*( abstract ) - 12:00 - Lunch
- 13:30 - Jan Philipp Wächter -
*Decision problems for automaton semigroups and groups*( abstract ) - 14:00 - Tara Macalister Brough -
*Preserving self-similarity in free products of semigroups*( abstract ) - 14:30 - Matthew Brookes -
*Congruences on direct products of simple semigroups*( abstract ) - 15:00 - Coffee break
- 15:30 - Tim Stokes -
*Can constellations shed light on semigroups?*( abstract ) - 16:30 - Close

**Registration.** Registration for the BMC is now
open,
and costs £120.
The NBSAN meeting is free to attend, but for planning purposes
we ask you to register using this form.

**Financial Support.** We have limited funds available to
contribute to the attendance costs of NBSAN participants without access to other funding sources.
To express an interest in support please
email
Nóra Szakács with details of your expected costs and
any other sources of funding available to you.

**Contact/queries.** For questions about the NBSAN meeting
and the semigroups content of the BMC please
email Marianne Johnson.
(For general queries about the BMC please
see the BMC website or email
bmc2024@manchester.ac.uk.)

**Sponsors.**The NBSAN meeting is generously supported by the Engineering and Physical Sciences Research Council, the Heilbronn Institute for Mathematical Research, the London Mathematical Society and the Department of Mathematics at the University of Manchester. Sponsors for the BMC meeting are detailed on the BMC website.

## Future Meetings

To receive announcements about future meetings, please email Mark Kambites and request to be added to the NBSAN mailing list.

## Past Meetings

For the archive of information about past meetings look here.

## Other (non-NBSAN) Events and Semigroup News

- A UK Operator Algebras Conference, to be held in Newcastle from 12th-14th June 2024, will include some content at the interface of semigroup theory and functional analysis.
- The 75th British Mathematical Colloquium, to be held in Manchester in the week commencing 17th June 2024, will feature lots of relevant activity, including a special session dedicated to semigroups - see above for details of the main meeting and the NBSAN satellite meeting.
- There is a conference on Semigroups, Groupoids and C*-algebras in Seoul, South Korea from 1st-5th July 2024.
- A conference on Theoretical and Computational Algebra, including lots of semigroups, will take place in Aveiro, Portugal from 30th June - 5th July 2024.