We give new explicit constructions of several fundamental objects in linear-algebraic pseudorandomness and combinatorics, including lossless rank extractors, weak subspace designs, and strong $s$-blocking sets over finite fields.

Our focus is on the small-field regime, where the field size depends only on a secondary parameter (such as the rank or ... more >>>

The subspace design property for additive codes is a higher-dimensional generalization of the minimum distance property. As shown recently by Brakensiek, Chen, Dhar and Zhang, it implies that the code has similar performance as random linear codes with respect to all “local properties”. Explicit algebraic codes, such as folded Reed-Solomon ... more >>>

We develop a topological framework for proving lower bounds on sign-rank via $\mathbb{Z}_2$–equivariant topology, and use it to resolve the sign-rank of the Gap Hamming Distance problem up to lower-order terms.

For every (partial) sign matrix $A$, we associate a free $\mathbb{Z}_2$–simplicial complex $S(A)$ and show that sign-rank of $A$ ... more >>>