Entanglements of Logic, Data, and Complexity
Symposium
Start date: 08.11.2025
End date: 11.11.2025
Event location: Institute of Mathematics and Informatics, Bulgarian Academy of Sciences
Zoom: https://us06web.zoom.us/j/88606075927?pwd=Jsj1aP8VsSZCfr8IvzOflEeaUTMctt.1
How do knots teach us about data?
Can sandpiles inform, through complex systems, a deeper understanding of mathematical logic?
What lies beyond the Church–Turing boundary in our age of quantum algorithms and polymodels?
The Symposium on Complex Systems, Data, and Topology is a four-day gathering exploring the frontiers of mathematics, machine learning, geometry, and real-world complexity. Set within the vibrant intellectual atmosphere of ICMS Sofia, the symposium brings together a select group of international researchers to discuss new ideas, paradigms, and tools shaping the future of science and computation.
Our sessions will feature four intersecting threads:
- Young Talents, sharing emerging directions at the intersection of topology and data science.
- Core Researchers from the local Complex Sandpile Group at ICMS presenting their recent results.
- Senior Established Mathematicians, offering insights into foundational and future-facing work.
- Industry Thought Leaders, reflecting on applied complexity in the real world.
This symposium is organized by the Research Group on Topological, Computational, and Algebraic Aspects of Complex Systems, hosted at the Institute of Mathematics and Informatics, Bulgarian Academy of Sciences.
The symposium is supported by Simons Foundation Grant of ICMS-Sofia and the Ministry of Education and Science of the Republic of Bulgaria, Scientific Programme PIKOM.
We warmly invite you to join these events celebrating the intersections of topology, data, and computation in the spirit of John Vincent Atanasoff and the Bulgarian Academy of Sciences!
Attendance and Registration
Talks are by invitation only. A limited number of additional seats are available for scholars and collaborators upon request.
To inquire about attendance, please contact:
Dr. Mikhail Shkolnikov
ICMS Sofia, Bulgarian Academy of Sciences
Email: shkolnikov@math.bas.bg
Invited Participants:
- León Palafox — GBM, Mexico
- Gerardo Hernández — CEMLA, Mexico
- Brenda Rocha — AXA, Mexico
- Javier Marín — BBVA, Mexico
- Josep Amoros — BBVA, Spain
- Edison Vázquez — CINVESTAV, Mexico
- Pedro Olivares — ITAM, Mexico
- Carlos Ruiz — Escuela Bourbaki, Mexico
- Asier Rodríguez — BBVA, Spain
- Paloma Marín — BBVA, Spain
- Daniel Sánchez — BBVA, Spain
- David Stephenson — DSI Analytics, UK
- Aldo Guzmán — IBM Research, Spain
- Raphaël Douady — University Paris 1 Pantheon-Sorbonne
- Carlos Simpson — CNRS, Université Côte d’Azur
- Mikhail Shkolnikov — ICMS Sofia, Bulgaria
- Higinio Serrano — ICMS Sofia, Bulgaria
- Yuri Tschinkel — Simons Foundation / Courant NYU
- Amaury Hayat — École des Ponts – IP Paris
- Phillip A. Griffiths — Institute for Advanced Study, Princeton
- Konstantin Delchev — IMI–BAS Sofia
- Ernesto Lupercio — CINVESTAV & ICMS Sofia
Programme
November 8, 2025 (Saturday)
Foundations of Complexity and Geometry
09:50–10:00 Opening Remarks — Julian Revalski (Director ICMS)
10:00–10:40 Mikhail Shkolnikov (ICMS Sofia, Complexity Group)
Title: Emergent Symmetry and Top–Bottom Causality in Self-Organised Criticality
Abstract:
The tropical sandpile model exhibits emergent continuous symmetries arising from discrete dynamics.
The talk examines how local interactions generate large-scale affine structures and how “top-bottom causality”
governs multi-scale organization.
10:50–11:30 Higinio Serrano (ICMS Sofia, Complexity Group)
Title: Entropy in Sandpile Groups
Abstract:
Analysis of Shannon entropy across configurations of sandpile groups on finite graphs,
exploring links between algebraic structure and information content.
11:40–12:20 Konstantin Delchev (IMI–BAS Sofia)
Title: On the Cyclic Subgroup Generated by the Teotitlán Element in the Sandpile Group
Abstract:
This talk examines a cyclic subgroup of the sandpile group generated by the so-called Teotitlán element.
We will discuss its construction, its growth behavior, and the structure of several low-order elements within this subgroup.
The presentation will also outline working hypotheses on the subgroup’s properties and potential approaches
for gaining deeper insight into its algebraic and combinatorial nature.
12:30–13:10 Carlos Ruiz (Escuela Bourbaki, Mexico)
Title: Mathematical Logic and Sparse Learning Theory
Abstract:
Overview of how logical frameworks explain the learnability of sparse datasets
and their relation to model complexity.
13:10–14:30 Lunch break
14:30–15:10 Pedro Olivares (ITAM, Mexico)
Title: Unknotting with Clasp Diagrams
Abstract:
Presentation of clasp diagrams (Mostovoy–Polyak) as combinatorial tools for knots.
A Python library enables visualization and invariant computation, giving new insight
into the algorithmic complexity of unknotting.
15:20–16:00 Round Table I: Topology Meets Complex Systems
Moderator: Ernesto Lupercio
Participants: C. Ruiz, L. Palafox, K. Delchev
Discussion Questions
- How do topological invariants manifest in emergent complex phenomena?
- Can categorical or Hodge-theoretic tools capture network resilience and self-organization?
- What models link local rules with global geometric complexity?
November 9, 2025 (Sunday)
Dialogues on Complexity and Finance
10:00–11:30 Round Table II – Complexity & Finance
Moderators: Ernesto Lupercio & Gerardo Hernández
Discussion Questions
- How does market geometries (fractal and otherwise) evolve under high-frequency feedback loops?
- What parallels exist between financial systems and non-equilibrium physical systems?
- Can AI and topological data analysis provide predictive robustness in finance?
11:30–12:00 Coffee / Networking at STEPS
Afternoon: Arrival of Atanasoff Lecturer — Amaury Hayat (École des Ponts – IP Paris)
November 10, 2025 (Monday)
Atanasoff Memorial Day: Mathematics and Machine Learning
10:00–10:50 Public Lecture — Ernesto Lupercio (CINVESTAV & ICMS Sofia)
Title: The Algebra of Avalanches: From Sandpiles to the Hidden Symmetries of the Universe
Abstract:
Why do avalanches, neural networks, and financial systems all seem to live on the edge of chaos?
This public lecture introduces the mathematics of the Teotitlán group — a new algebraic structure that captures how complex systems organize themselves.
Born from the humble sandpile, the Teotitlán group reveals that every collapse leaves behind a hidden order, an “arithmetic memory” encoded in the geometry of the system.
From grains of sand to networks, from topology to machine learning, we discover how balance, symmetry, and information emerge spontaneously.
No formulas required — just curiosity, pattern, and imagination.
13:00–13:50 Raphaël Douady (Université Paris 1 Panthéon-Sorbonne & University of New York at Stony Brook)
Title:
Panesthetic analysis: Using the future potential behavior of assets rather than the past in a complex environment
Abstract:
We shall focus particularly on financial assets, although the considerations of this talk apply to any kind of assets whose behavior is influenced by a complex environment driven by a very large number of variables.
Fund analysis and selection, portfolio construction, classically use a statistical analysis of past returns to estimate econometric models, identify risk factors and exposures, and finally come up with investment decisions.
This approach implies a misalignment between the informational contribution of the data being analyzed and their impact on the criteria used for decision making.
Panesthetic analysis consists of first identifying a list of scenarios of the environment behavior that best reflects the expectations and risks of the investment.
Then separately estimate, from known data, the behavior of each asset in each of these scenarios, together with a measure of the uncertainty on these estimates.
Such an approach provides a much better control over the potential extreme events that may occur in the future, by attributing to them the importance they deserve.
The estimate of the impact of large events is provided by nonlinear polymodel analysis, while optimal transport measures are used to replicate and hedge the risks of a fund or a portfolio.
14:00–14:50 Carlos Simpson (CNRS, Université Côte d’Azur)
15:00–15:50 Atanasoff Keynote Lecture — Amaury Hayat (École nationale des Ponts et Chaussées – Institut Polytechnique de Paris / Korean Institute for Advanced Studies)
Title: What Role for AI in the Future of Mathematics?
Abstract:
The advent of artificial intelligence raises an important question: how will AI transform the practice of mathematics?
This talk explores this question from multiple angles. We will examine how machine learning techniques can provide valuable insights into mathematical problems and help solve challenging questions, motivating our discussion with examples of problems arising from nonlinear control theory. We will in particular review how transformer models can learn the underlying structure of mathematical problems to predict useful quantities. We will also discuss recent advances in automated theorem proving, investigate the use of large language models (LLMs) and various reinforcement learning approaches, and explore future perspectives.
16:00–16:50 Yuri Tschinkel (Simons Foundation / Courant NYU)
Title:
Enhanced invariants in equivariant birational geometry
Abstract:
I will discuss some recent constructions in equivariant birational geometry.
17:00–17:50 Phillip Griffiths (Institute for Advanced Study, Princeton)
Title: Normal Functions and their Invariants
Abstract:
Normal functions and their infinitesimal invariants are basic Hodge theoretic invariants of a pair (X, Z), where X is a smooth projective variety and Z is an algebraic subvariety or algebraic cycle in X. They have both a structure and applications to examples, and in this talk we will give an expository account of some aspects of the theory, with emphasis on the singularity structure and some open issues.
IMI Award Ceremony follows immediately
Lunch: Served at ICMS
Cocktail Reception: After the IMI Award at ICMS Sofia
November 11, 2025 (Tuesday)
Data, Institutions, and the Geometry of Markets
09:00–09:30 Edison Jessie Vázquez Gordillo (CIMAT – Unidad Monterrey)
Title:
Learning Topological Invariants: How Autoencoders Capture the Geometry of the Knot Signature
Abstract:
Topological invariants reveal the hidden order behind knots, preserving what remains unchanged through deformation.
In this work, we show that autoencoders, when trained on the coefficients of the Alexander and Jones polynomials,
can learn latent geometries that reflect the knot signature. The learned latent space organizes knots according to
their algebraic and geometric features, rediscovering invariance relations without explicit supervision. This
suggests that deep learning can serve as an analogue to mathematical reasoning, revealing how signature and topology
emerge naturally from the structure of data.
09:40–10:10 Daniel Sánchez (BBVA Barcelona)
10:20–10:50 Paloma Marín (BBVA Madrid)
Title:
Causality in Market Microstructure: Bridging Probabilistic Models and Machine Learning for Decision-Making in Financial Platforms
Abstract:
Modern financial markets are increasingly driven by data and automation, yet most algorithmic systems remain purely
correlational.
This talk explores how causal reasoning and probabilistic graphical models can enhance decision-making in complex,
data-mediated environments such as multi-dealer-to-client (MD2C) bond trading platforms.
Using the Request-for-Quote (RfQ) mechanism as a case study, a unified framework is presented connecting the
statistical modeling of market microstructure with the logic of interventions in causal inference. By representing
the negotiation process as a causal graph, we can analyze optimal pricing, estimate profitability under uncertainty,
and evaluate the effect of commercial actions such as client outreach.
The discussion contrasts generative models, which encode the structural logic of dealer–client interactions,
with discriminative and neural approaches that optimize predictive performance. Results show that causally
consistent models can match the accuracy of top machine-learning algorithms while preserving economic coherence
such as price monotonicity.
The talk concludes by outlining how causal logic and machine learning can coexist to yield interpretable,
intervention-ready AI systems for complex socio-economic environments.
11:00–11:30 León Palafox (GBM, Mexico)
Title:
Uses and Challenges of Academic Data Science in the Financial Sector
Abstract:
How academic data-science methods are adapted for business value, with case studies in investment personalization
and risk modeling, emphasizing reproducibility and governance.
11:30–12:00 Gerardo Hernández del Valle (CEMLA, Mexico)
Title:
Explicit Option Pricing Under Market Impact
Abstract:
Derivation of option-pricing formulas when large trades affect market prices.
Incorporates feedback effects into the binomial model to obtain closed-form corrections
relevant to illiquid markets.
12:00–12:15 Closing Remarks — Ernesto Lupercio & Organising Team
THE ATANASOFF MEMORIAL LECTURE SERIES
The Atanasoff Memorial Lecture Series is a new annual program of the Bulgarian Academy of Sciences and ICMS Sofia celebrating the intersection of mathematics, computation, and the sciences of complexity — the very domains that unite topology, geometry, and machine learning in the 21st century.
It honours John Vincent Atanasoff (1903–1995), inventor of the first electronic digital computing device — the Atanasoff–Berry Computer (ABC) — whose Bulgarian heritage and pioneering ideas transformed modern computation.
Each year an internationally distinguished scientist is invited as the Atanasoff Lecturer to deliver a keynote lecture connecting mathematical structure with computational innovation.
Public Lecture
THE ALGEBRA OF AVALANCHES
From Sandpiles to the Hidden Symmetries of the Universe
Ernesto Lupercio — Ramanujan Prize Laureate
Professor, CINVESTAV & ICMS Sofia
Why do avalanches, neural networks, and financial systems all seem to live on the edge of chaos?
This public lecture introduces the mathematics of the Teotitlán group — a new algebraic structure that captures how complex systems organize themselves. Born from the humble sandpile, the Teotitlán group reveals that every collapse leaves behind a hidden order, an “arithmetic memory” encoded in the geometry of the system.
From grains of sand to networks, from topology to machine learning, we discover how balance, symmetry, and information emerge spontaneously.
No formulas required — just curiosity, pattern, and imagination.
Date: Monday, November 10, 2025
Time: 10:00–10:50 AM
Venue: ICMS Lecture Hall, Acad. G. Bonchev St. Bl. 8, Sofia
Admission: Free · All welcome
Venue

Institute of Mathematics and Informatics at the Bulgarian Academy of Sciences
Saturday Lunch — Recommended Restaurants (walking distance from ICMS / IMI–BAS)
La Terra Sky Restaurant
Address: Sky City Center, 52 Kosta Lulchev St., 1574 Sofia
Rooftop dining with panoramic city views and a modern Mediterranean menu (≈ 5 min walk).
Talpa Restaurant & Garden
Address: 5A Hristo Chernopeev St., 1113 Sofia
Contemporary Bulgarian and European cuisine with outdoor garden seating (≈ 4 min walk).
Sushi Express (Kopernik)
Address: 25 Nikolay Kopernik St., 1113 Sofia
Quick Japanese and fusion lunch options — reliable for small groups (≈ 5 min walk).
Tea & Eat 1999
Address: 101 Tsarigradsko Shose Blvd., 1113 Sofia
Cozy café-restaurant serving salads, pasta, and teas; relaxed for informal discussion (≈ 5 min walk).
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