Computational Methods in Lattice Field Theories

28 Oct 2025, 08:00 → 1 Nov 2025, 13:50 Asia/Kolkata

CHEP, IISc

Debasish Banerjee (University of Southampton), BIPLOB BHATTACHERJEE (Indian Institute of Science), Justin R. David (Indian Institute of Science, Bangalore), Prasad Hegde (Indian Institute of Science), Ranjan Laha (Indian Institute of Science), Padmanath Madanagopalan (The Institute of mathematical Sciences Chennai), Indrakshi Raychowdhury (BITS Pilani K K Birla Goa Campus), Sayantan Sharma (IMSc), Sudhir Kumar Vempati, Maneesha Sushama Pradeep (IISc)

The Centre for High Energy Physics at the Indian Institute of Science, Bengaluru, will be organizing a school on Computational Methods in Lattice Field Theories, from October 28th - November 1st, 2025. The school will take place a week before the annual Lattice Conference, which will be held this year in India, at the Tata Institute of Fundamental Research (TIFR) in Mumbai, from November 2nd - 8th, 2025. The school aims at training Ph.D. students and young Postdoctoral Fellows in some of the frontier and contemporary topics in lattice field theory.

The following topics will be covered at the school:

• • • Quantum Computing for Lattice Field Theories.
    • Applications of Machine Learning to Lattice QCD.
    • Monte Carlo and Quantum Monte Carlo.
    • Hadronic Interactions from Lattice QCD.
    • QCD at Finite Temperature and Density.

 

The format will consist of lectures and tutorials on the above topics by various Invited Speakers:

• • • Arnab Sen                       (Indian Association for the Cultivation of Science, India)
    • Christian Schmidt          (Bielefeld University, Germany)
    • Emilie Huffman              (Wake Forest University, USA)
    • Gurtej Kanwar                 (University of Edinburgh, UK)
    • Jesse Stryker                  (Lawrence Berkeley National Laboratory, USA)
    • Jishnu Goswami            (RIKEN Advanced Institute for Computational Science, Japan)
    • Maxim Mai                      (University of Bern, Switzerland)
    • Srijit Paul                         (University of Maryland, USA)

Registration:

[Note: Pre-registration is now closed] To attend the school, candidates will first need to fill out a pre-registration form. Participation in the school will only be possible if the pre-registration is accepted. Preference will be given to junior postdocs and to Ph.D. students who are already working in the above-mentioned fields. A link to complete the registration process will be sent to the candidates whose pre-registration has been accepted.

Candidates will need to make their own travel arrangements to and from IISc Bangalore. However, we will be able to provide shared accommodation to some of the candidates for the duration of the conference. We expect to be able to support around 40 students and postdocs in total.

There is also a registration fee which will be used to cover some of the local expenses during the school. The fee is as follows:

• • • Students:      INR 4,500 + 18% GST.
    • Postdocs:     INR 6,000 + 18% GST.
    • Faculty:         INR 12,000 + 18% GST.

 

The registration fee will need to be paid only after the registration has been accepted.

You are welcome to write to us in case of any further queries. We look forward to seeing you later this year at IISc.

Tuesday 28 October

08:00 → 09:00 Registration

09:00 → 09:30 Welcome Address

09:30 → 11:00 Talk 1 - Maxim Mai (University of Bern, Switzerland): Approaches to low-energy QCD in a cross talk of EFTs and Lattice QCD

Robust accessing of low-energy QCD is necessary to understand the mass generation and emergence of spectrum of excited hadrons in nature. So far two approaches have crystallized to this goal, both, however, having own strengths and weaknesses. A combination of both approaches provides a path to salvage the former, and mitigate the latter.

Indeed, this synergetic approach provides a path to better understanding the low-energy structure of QCD by not only comparing the first-principles predictions with experimental observations but even going beyond this, allowing to study experimentally not accessible regimes. In my lectures, I will show basic principles behind these approaches and some hands-on applications thereof.

Lecture-MaximMai.pdf

11:00 → 11:30 Coffee Break

11:30 → 13:00 Talk 2 - Gurtej Kanwar (University of Edinburgh, UK): Machine learning methods for Monte Carlo sampling

In these lectures, I will discuss modern machine learning approaches to accelerate Monte Carlo sampling in lattice field theories. The core theme will be connecting to the idea of measure transport through (learned) deterministic and stochastic transformations.

13:00 → 14:00 Lunch Break

14:00 → 15:30 Talk 3 - Arnab Sen (Indian Association for the Cultivation of Science, India): Monte Carlo for lattice field theories

In these lectures, I will first motivate the equivalence of lattice field theories in Euclidean time to statistical mechanics models, and establish a dictionary between the two. I then discuss the general idea of Monte Carlo sampling in a class of models and finally focus on two interacting models in d dimensions as examples, a phi 4 theory and an Ising model. I explain the extraction of low lying masses using correlation functions and critical exponents at criticality using finite size scaling through these examples.

15:30 → 16:00 Coffee Break

16:00 → 17:30 Talk 4 - Srijit Paul (University of Maryland, USA): The Anatomy of a Lattice Measurement

We discuss how one goes from gauge configurations generated from Monte Carlo towards making a measurement to compute a physical observable. We elaborate on each step starting from relevant operators, propagator computations which are then contracted to obtain the final n-point correlation function. At every step, we tackle computational and analytical challenges using novel methods and techniques developed by the lattice community. As an example measurement, we discuss in particular proton and wilson loops, and finally a reliable extraction of a finite volume spectrum relevant for hadron spectroscopy.

Wednesday 29 October

09:00 → 10:30 Talk 5 - Maxim Mai (University of Bern, Switzerland): Approaches to low-energy QCD in a cross talk of EFTs and Lattice QCD

Robust accessing of low-energy QCD is necessary to understand the mass generation and emergence of spectrum of excited hadrons in nature. So far two approaches have crystallized to this goal, both, however, having own strengths and weaknesses. A combination of both approaches provides a path to salvage the former, and mitigate the latter.

Indeed, this synergetic approach provides a path to better understanding the low-energy structure of QCD by not only comparing the first-principles predictions with experimental observations but even going beyond this, allowing to study experimentally not accessible regimes. In my lectures, I will show basic principles behind these approaches and some hands-on applications thereof.

10:30 → 11:00 Coffee Break

11:00 → 12:30 Talk 6 - Gurtej Kanwar (University of Edinburgh, UK): Machine learning methods for Monte Carlo sampling

In these lectures, I will discuss modern machine learning approaches to accelerate Monte Carlo sampling in lattice field theories. The core theme will be connecting to the idea of measure transport through (learned) deterministic and stochastic transformations.

12:30 → 14:00 Lunch

14:00 → 15:30 Talk 7 - Arnab Sen (Indian Association for the Cultivation of Science, India): Monte Carlo for lattice field theories

In these lectures, I will first motivate the equivalence of lattice field theories in Euclidean time to statistical mechanics models, and establish a dictionary between the two. I then discuss the general idea of Monte Carlo sampling in a class of models and finally focus on two interacting models in d dimensions as examples, a phi 4 theory and an Ising model. I explain the extraction of low lying masses using correlation functions and critical exponents at criticality using finite size scaling through these examples.

15:30 → 16:30 Poster Session (With Coffee break)

16:30 → 18:00 Talk 8 - Srijit Paul (University of Maryland, USA): Machine Learning in Measurements

We summarize the recent machine learning efforts to tackle the computational and analytical challenges one faces in performing a lattice measurement. We start with direct methods which take in configurations and try to predict the final physical observable/correlator. Next, we briefly touch upon ML methods to perform inversions. Finally we elaborate on various noise reduction and computational effort reduction strategies using ML techniques.

Thursday 30 October

09:00 → 10:30 Talk 9 - Christian Schmidt (Bielefeld University, Germany): Lattice Fundamentals and equation of state

After a short motivation for lattice methods in general, I will introduce the fermionic path integral and discuss fermionic cutoff effects at finite temperature. I will then discuss a lattice calculation of the equation of state at zero chemical potential and its connection to perturbation theory at high temperature and to the hadron resonance gas at low temperature

10:30 → 11:00 Coffee Break

11:00 → 12:30 Talk 10 - Emilie Huffman (Wake Forest University, USA): Introduction to Quantum Computing

This is an introductory lecture for the elements of quantum computing. We'll begin with classical bits and possible reversible operations on them, and then extend the discussion to quantum bits, introducing as well measurement, circuit diagrams, and finishing with an example of measuring an energy for a simple Hamiltonian.

12:30 → 14:00 Lunch

14:00 → 15:30 Talk 11 - Jesse Stryker (Lawrence Berkeley National Laboratory, USA): Introduction to quantum computing (continued)

This lecture can be viewed as a continuation of the earlier lecture by Prof. Huffman. Topics will include quantum algorithm examples (such as quantum Fourier transform) and a first introduction to Hamiltonian lattice gauge theory.

15:30 → 16:00 Coffee Break

16:00 → 17:30 Talk 12 - Jishnu Goswami (RIKEN Advanced Institute for Computational Science, Japan): Strangeness Correlations and QCD Material Parameters (HISQ)

This lecture develops the lattice definitions and computation of strangeness fluctuations and cross-correlations $(\chi_2^S,\chi_{11}^{BS},\chi_{11}^{QS})$ together with baryon-number skewness/kurtosis $(\chi_3^B,\chi_4^B)$ and ratios $S\sigma, \kappa\sigma^2$. Emphasis is on the HISQ pipeline (Taylor expansion, continuum extrapolation ) and how to interpret the temperature and chemical potential trends relevant to fluctuation measurements at RHIC.

17:30 → 19:30 Poster Session

19:30 → 21:00 Special Dinner

Friday 31 October

09:00 → 10:30 Talk 13 - Christian Schmidt (Bielefeld University, Germany): Cumulants of conserved charge fluctuations and the QCD phase diagram

I will introduce Taylor coefficients of the pressure and discuss their interpretation in terms of conserved charge fluctuations. I will further show how they can be used to explore the QCD phase diagram at nonzero temperature and density with emphasis  on the chiral transition and the QCD critical point.

10:30 → 11:00 Coffee Break

11:00 → 12:30 Talk 14 - Emilie Huffman (Wake Forest University, USA): Hamiltonian Lattice Field Theories and Variational Eigensolver Algorithms

Continuing on with the Hamiltonian Field theories introduced in the previous lecture, we consider different ways of getting a finite-dimensional Hilbert space. We discuss the Schwinger model and how to simulate fermions with the Jordan-Wigner transformation, and finally we consider quantum link models and the application of both VQE/VQD and QAOA to find the ground state and first-excited state to an SO(3)-symmetric quantum link model.

12:30 → 14:00 Lunch

14:00 → 15:30 Talk 15 - Jesse Stryker (Lawrence Berkeley National Laboratory, USA)

15:30 → 16:00 Coffee Break

16:00 → 17:30 Talk 16 - Jishnu Goswami (RIKEN Advanced Institute for Computational Science, Japan): Thermodynamics with Möbius Domain-Wall Fermions at Finite $T$ and $\mu$

A pedagogical walk-through of finite-$T$, small-$\mu$ thermodynamics with MDWF: action choices, chiral symmetry, and practical estimators for conserved-charge cumulants. We outline noise/systematics control and continuum estimation, and contrast with HISQ to highlight where exact chiral symmetry refines fluctuation observables of interest to heavy-ion phenomenology.

Saturday 1 November

09:00 → 10:00 Talk 17 - Christian Schmidt (Bielefeld University, Germany): Universal scaling fits

I will perform a hands-on exercise of a chiral scaling fit to HotQCD data using a well known parametrization of the universal scaling function of the order parameter. From the fit we extract the chiral phase transition temperature.

10:00 → 11:00 Talk 18 - Srijit Paul (University of Maryland, USA): School Summary

We summarize the discussions and interesting outcomes of the school with regards to ML in lattice QCD and hadron spectroscopy.

12:30 → 13:50 Lunch