Ijay Narang

collaborators

11 papers

math.AC2026

Test ideals can be computed by boundaries

Rahul Ajit, with Appendix joint with Daniel Apsley

Let $R$ be a normal $F$ -finite ring of characteristic $p > 0$ . We show that one effective $Q$ -divisor $Δ$ , with $K_{R} + Δ$ $Q$ -Cartier of index prime to $p$ , computes…

cs.CV2026

Hob-VL: A Benchmark for Visually Grounded Boolean Reasoning

Yuzhou Wang, Emile Anand, Ijay Narang

Reliable visual reasoning requires composing multiple visual observations and returning consistent answers to logically equivalent questions. We introduce Hob-VL, a benchmark for v…

cs.DS2026

Improved SDP Coloring of 3-Colorable Graphs from Recursive Gaussian Certificates

Ijay Narang, Yukai Tang

We give a randomized polynomial-time algorithm that, for every fixed $ε > 0$ , colors every $3$ -colorable $n$ -vertex graph using $O\bigl(n^{(13-\sqrt{97})/18+\varepsilon}\…

math.OC2026

Complexity of Output Feedback Stabilization

Amir Ali Ahmadi, Abraar Chaudhry, Ijay Narang +1

We show that unless P = NP, there cannot be a polynomial-time (or even pseudo-polynomial-time) algorithm for output feedback stabilization of a linear dynamical system with a linea…

cs.DS2026

Structural Corrections to the Bethe Approximation of the Permanent

Ijay Narang, Will Perkins

We study deterministic approximation algorithms for the permanent of a nonnegative matrix through the Bethe permanent, an approximation computable in polynomial time. The tight ana…

cs.DS2026

The Hard-Core Model on Bipartite Spectral Expanders: Counting and Sampling at All Fugacities

Ijay Narang, Will Perkins

We study approximate counting and sampling algorithms for the hard-core model on $Δ$ -regular bipartite graphs under a spectral expansion condition. Let $M_{G}$ be the biadjacency mat…

cs.DS2026

Computational Thresholds for Balanced and Fixed-Slice Independent Sets in Bipartite Graphs

Ijay Narang, Will Perkins, Yuzhou Wang +1

Motivated by recent work of Kocurek, Oveis Gharan, and Tjowasi, which gives an efficient sampling algorithm for the hard-core model on random regular bipartite graphs by decomposin…

math.CO2026

Schrijver Number Quasi-Tensorization and Multicolor Ramsey Bounds via Robust OR Polynomials

Ijay Narang, Yukai Tang

We introduce a robust OR polynomial framework for composing positive semidefinite certificates across OR constraints. We demonstrate the power of this method in two applications. T…

math.ST2026

Optimal detection of planted stars via a random energy model

Ijay Narang, Will Perkins, Timothy L. H. Wee

We study the problem of detecting a planted star in the Erd{ő}s--R{é}nyi random graph $G (n, m)$ , formulated as a hypothesis test. We determine the scaling window for critical detect…

cs.LG2026

Constant-Stepsize Stochastic Approximation: Finite-Time Convergence, Gaussian Approximation, and Tail Bounds

Zedong Wang, Yuyang Wang, Ijay Narang +3

Constant-stepsize stochastic approximation (SA) is widely used in learning for computational efficiency, yet the distribution of the iterates is typically intractable. Classical as…

math.CO2025

Sharp Inner Product Correlations for Hypercube Bijections

Ijay Narang, Muchen Ju

We resolve a conjecture of Rob Morris concerning bijections on the hypercube. Specifically, we show that for any bijection $f : {- 1, 1}^{n} \to {- 1, 1}^{n}$ , \[ \Pr_{x,y \in \{-1,1\}…