AGATES Workshop

Geometry of secants

October 24th-28th, 2022

IMPAN, Warsaw, Poland

The workshop "Geometry of Secants" is dedicated to classical algebraic geometry related to secant varieties and decompositions.  We plan to cover topics that are close to Terracini- and Scorza-style geometry, also with relations to birational problems, and other stuff about secant varieties, mainly focusing on aspects of  interest for algebraic geometers.

List of topics:

  • defectivity of secant varieites,
  • identifiability, 
  • singularities of secant varieties,
  • defining ideals of secant varieties,
  • configurations of points on projective manifolds,
  • linear systems on projective varieties and manifolds that are related to secant varieties,
  • elementary scheme-theoretic methods,
  • dual varieties.

Open questions

During the group discussions, participants raised interest on some open questions. The list of these conjectures and problems is here.


Institutional organisers

Confirmed speakers


The workshop takes place at Institute of Mathematics of Polish Academy of Sciences (IMPAN). The address is Śniadeckich 8, 00-656 Warsaw, Poland. Lectures will take place in room number 321 on the third floor.

Some hints on the accommodation are available at the AGATES accommodation tab. Note that some supported participants must reserve their accommodations through the University of Warsaw, see the above webpage for details.

As of now, we plan the workshop as an in-person event and we do not foresee any possibility of on-line participation.



Monday, Oct 24

Tuesday, Oct 25 Wednesday, Oct 26 Thursday, Oct 27

 Friday, Oct 28


 Han [slides]
 Choe [slides]
 Coffee break, room 409
 Coffee break, room 409  Coffee break, room 409  Coffee break, room 409  Coffee break, room 409
 Di Rocco  Ranestad  Ottaviani  Ciliberto [slides]


 Gimigliano [slides]  Laface [slides]
 Torrance [slides]




 Lunch break  Lunch break
 (free afternoon)  Lunch break  Lunch break
 Discussions and working groups, phrasing the problems, initial questions, room 321
 Discussions and working groups, rooms 6, 321, 408

 (free afternoon)

 Discussions and working group, rooms 6, 321, 408  Discussions and working groups, general assembly, room 321
 Coffee break, room 409  Coffee break, room 409
 (free afternoon)  Coffee break, room 409  Coffee break, room 409
 Discussions and working groups, dividing into problem groups
 Discussions and working groups, general assembly, room 321
 (free afternoon)  Discussions and working group, rooms 6, 321, 408    

 Workshop dinner


Programme and abstracts

Prerequisites and preworkshop teach-in

Speakers of the workshop will freely use several concepts that are common to the topics addressed at the workshops: secant varieties, expected dimension, apolarity action, Hilbert function, various notions of rank, identifiability, Terracini's Lemma. For participants' convenience we prepared a brief cheat sheet ("ściąga" in Polish) with such definitions and their basic properties (the file will be updated soon). In addition, during the week prior to the workshop there was a special meeting (in hybrid format) when you can ask questions and comment on those notions. This teach-in meeting was on Thursday, 20 Oct at 16:10 (in hybrid format: at IMPAN room 405, and via zoom).

Working groups

  1. Terracini Loci and high Veronese of X is non-defective, room 321.
  2. Secants of low degree, room 6.
  3. Subschemes of P^2, room 408.

Conference picture



To attend, please fill in the AGATES registration form, indicating that you plan to attend the workshop in the section "Interest in events".

Financial support and institutions involved

The workshop is a part of a semester long program Algebraic Geometry with Applications to TEnsors and Secants (AGATES), which is supported by the Simons Foundation and by Institute of Mathematics of Polish Academy of Sciences.