Research

I love all things scientific/mathematical. My primary areas of interest are:

• Discrete optimization, graph theory and clustering algorithms
• Uncertainty quantification and rare events
• Quantum computation
• Nonlinear dynamics, bifurcation theory, numerical methods, and hybrid systems
• Distributed Computation
• Mechanics and Dynamics of Nano- and Micro-mechanical Systems

Journal publications

1. T. Sahai, A. Gnanasekaran, On the Emergence of Ergodic Dynamics in Unique Games, In Review. [arxiv link]
2. A. Surana, A. Gnanasekaran, T. Sahai, An efficient quantum algorithm for simulating polynomial differential equations, Quantum Information Processing. [journal link] [arxiv link]
3. B. Zhang, T. Sahai, Y. Marzouk, Computing eigenfunctions of the multidimensional Ornstein-Uhlenbeck operator, In Review. [arxiv link]
4. J. Xing, D. Fischer, N. Labh, R. Piersma, B. C. Lee, Y. Xia, T. Sahai, V. Tarokh, Talaria: A Framework for Simulation of Permissioned Blockchains for Logistics and Beyond, In Review. [arxiv link]
5. B. Zhang, T. Sahai, Y. Marzouk, A Koopman framework for rare event simulation in stochastic differential equations, Journal of Computational Physics, 2022. [journal link] [arxiv link]
6. T. Sahai, Stochastic Optimization using Polynomial Chaos Expansions, In Review. [arxiv link]
7. T. Sahai, A. Mishra, J.M. Pasini, S. Jha, Estimating the Density of States of Boolean Satisfiability Problems on Classical and Quantum Computing Platforms, In Review. [arxiv link]
8. R. Varma, C. Melville, C. Pinello, T. Sahai, Post Quantum Secure Command and Control of Mobile Agents : Inserting quantum-resistant encryption schemes in the Secure Robot Operating System, International Journal of Semantic Computing, 2021 [journal link]
9. T. Sahai, A. Ziessler, S. Klus, M. Dellnitz, Continuous Relaxations for the Traveling Salesman Problem, Nonlinear Dynamics, 2019. [journal link] [arxiv link]
10. I. Mezic, V. A. Fonoberov, M. Fonoberova, T. Sahai, Spectral Complexity of Directed Graphs and Application to Structural Decomposition, Complexity, 2019. [journal link] [arxiv link]
11. Susmit Jha, T. Sahai, V. Raman, A. Pinto, M. Francis, Explaining AI Decisions Using Efficient Methods for Learning Sparse Boolean Formulae, Journal of Automated Reasoning, 2019. [journal link] [pdf link]
12. S. Jha, A. Tiwari, S. A. Seshia, T. Sahai, N. Shankar, TeLEx: Learning Signal Temporal Logic from Positive Examples using Tightness Metric, Formal Methods in System Design, 2019. [journal link] [pdf link]
13. S. Klus, T. Sahai, A Spectral Assignment Approach for the Graph Isomorphism Problem, Information and Inference: A Journal of the IMA, 2018. [journal link] [arxiv link]
14. J.M. Pasini and T. Sahai, Polynomial Chaos based Uncertainty Quantification in Hamiltonian, Multi-Time Scale and Chaotic Systems. Journal of Computational Dynamics, 2014 [journal link] [arxiv link]
15. T. Sahai and J.M. Pasini, Uncertainty Quantification in Hybrid Dynamical Systems. Journal of Computational Physics, 2012. [journal link] [arxiv link]
16. A. Surana, T. Sahai and A. Banaszuk, Iterative Methods for Scalable Uncertainty Quantification in Complex Networks, International Journal for Uncertainty Quantification, 2012. [journal link] [arxiv link]
17. T. Sahai, A. Speranzon and A. Banaszuk, Hearing the Clusters in a Graph: A Distributed Algorithm, Automatica, 2012. [journal link] [arxiv link] (Top 25 most downloaded Sciencedirect papers)
18. A. Banaszuk et al., Scalable Approach to Uncertainty Quantification and Robust Design of Interconnected Dynamical Systems, Annual Reviews in Control, 2011. [journal link] [arxiv link]
19. S. Klus, T. Sahai, C. Liu and M. Dellnitz, An efficient algorithm for the parallel solution of high-dimensional differential equations, Journal of Computational and Applied Mathematics, 2011. [journal link] [arxiv link]
20. T. Sahai, Backbone Transitions and Invariant Tori in Forced Micromechanical Oscillators with Optical Detection, Nonlinear Dynamics, 2010. - [journal link] [pdf]
21. T. Sahai, V. Fonoberov and S. Loire, Uncertainty as Stabilizer of the Head-Tail Ordered Phase in Carbon-Monoxide Monolayers on Graphite, Physical Review B, 2009. [journal link] [pdf]
22. T. Sahai and A. Vladimirsky, Numerical Methods for Approximating Invariant Manifolds of Delayed Systems, SIAM Journal on Applied Dynamical Systems, 2009. [journal link] [pdf] (Top 15 most downloaded papers - September 2009)
23. T. Sahai and A. Zehnder, Modeling of Coupled Dome-Shaped Micro-Oscillators, IEEE/ASME Journal of MEMS, 2008. [journal link] [pdf]
24. T. Sahai, R. Bhiladvala and A. Zehnder, Thermomechanical Transitions in Doubly-Clamped Micromechanical Oscillators, International Journal of Nonlinear Mechanics, 2007. [journal link] [pdf]
25. P. Raghavendra, T. Sahai, P. Kumar, M. Chauhan and N. Ananthkrishnan, Aircraft Spin Recovery, with and without Thrust Vectoring, Using Nonlinear Dynamic Inversion, Journal of Aircraft, 2005. [journal link]
26. N. Ananthkrishnan and T. Sahai, Crises - Critical junctures in the life of a chaotic attractor, Resonance, 2001. [journal link] [pdf]

Select conference publications (peer reviewed and distinct from all journal papers)

• H. Saidi, S. Jha, T. Sahai, math-PVS: A Large Language Model Framework to Map Scientific Publications to PVS Theories, In Review, [arxiv link]
• A. Gnanasekaran, A. Surana, T. Sahai, Efficient Quantum Algorithms for Nonlinear Stochastic Dynamical Systems, IEEE International Conference on Quantum Computing and Engineering (QCE23), [conference link] [arxiv link]
• H. Zhu, S. Klus, T. Sahai, A Dynamic Mode Decomposition Approach for Decentralized Spectral Clustering of Graphs, IEEE CCTA 2022, [conference link][arxiv link]
• B. Zhang, T. Sahai, Y. Marzouk, Sampling via Controlled Stochastic Dynamical Systems, Neurips ICBINB workshop, [conference link], 2021.
• R. Varma, C. Melville, C. Pinello, T. Sahai, Post Quantum Secure Command and Control of Mobile Agents : Inserting quantum-resistant encryption schemes in the Secure Robot Operating System, IEEE Conference on Robotic Computing, 2020. [conference link][arxiv link]
• T. Sahai, Dynamical Systems Theory and Algorithms for NP-hard Problems, Workshop on Set Oriented Numerics 2020. [conference link][arxiv link]
• T. Sahai, A. Mishra, J.M. Pasini, S. Jha, Estimating the Density of States of Boolean Satisfiability Problems on Classical and Quantum Computing Platforms, AAAI 2020 (Oral Presentation in Main Conference - ~5% acceptance rate). [pdf link] [arxiv link]
• B. Zhang, Y. Marzouk, B.-Y. Min and T. Sahai, Rare Event Simulation of a Rotorcraft System, AIAA SciTech Forum, 2018. [conference link] [pdf link]
• S. Jha, V. Raman, A. Pinto, T. Sahai, and M. Francis, On Learning Sparse Boolean Formulae For Explaining AI Decisions, NASA Formal Methods (NFM), 2017. [conference link] [pdf link]
• S. Jha, A. Tiwari, S. A. Seshia, N. Shankar, and T. Sahai, TeLEx: Passive STL Learning Using Only Positive Examples, 17th International Conference on Runtime Verification (RV), 2017. [conference link] [pdf link]
• T. Sahai, G. Mathew, A. Surana, A Chaotic Dynamical System that Paints and Samples, IFAC 2017. [conference link] [arxiv link] [code repository]
• K. Srivastava and T. Sahai, A Multiresolution Approach for Tensor Factorization, NIPS 2015. [conference link] [video link]
• B. Englot, T. Sahai, I. Cohen, Efficient Tracking and Pursuit of Moving Targets by Heuristic Solution of the Traveling Salesman Problem, 52nd IEEE Conference on Decision and Control 2013. [conference link] [pdf link]

Patents

• Method and Apparatus for Cooperative Multi-Target Assignment, 173057US01. Filed January 2023
• Distributed Satellite Constellation for Cooperative Multi-target Tracking. Filed August 2022
• Spectral clustering of graphs on fault tolerant and noisy quantum devices. Application Number: US20230409943A1. Filed June 2022
• Decentralized graph clustering using the Schrodinger equation. Application Number: US20230409643A1. Filed June 2022
• Quadratic Assignment Problem and Blackboard wiring using lattices. Application Number: US20230153481A1. Filed November 2021
• Floor Plan Based Planning of Building Systems. Application Number: PA-0032689-US, Awarded: June 2021
• Systems and Methods for Providing a Graphical User Interface Indicating Intruder Threat Levels for a Building. Application Number: PA-0032692-US, Awarded: October 2019
• System and Method for Automatic Learning of Bayesian Networks. Application Number: US2015/0142709, Filed: November 2014
• Comfort Estimation and Incentive Design for Energy Efficiency, Application Number: PCT/US12/67029, Filed: November 2012

Working Papers

• T. Neema, S. Jha, T. Sahai, Non-Markovian Quantum Control via Model Maximum Likelihood Estimation and Reinforcement Learning, [pdf]
• T. Sahai, S. Klus, M. Dellnitz, A Traveling Salesman Learns Bayesian Networks, [pdf]
• E. Sahai, T. Sahai, Mapping and Reducing the Brain on the Cloud, [pdf]