The Unique Games conjecture (UGC) has emerged in recent years as the starting point for several optimal inapproximability results. While for none of these results a reverse reduction to Unique Games is known, the assumption of bijective projections in the Label Cover instance seems critical in these proofs. In this ... more >>>

We prove two new multivariate central limit theorems; the first relates the sum of independent distributions to the multivariate Gaussian of corresponding mean and covariance, under the earthmover distance matric (also known as the Wasserstein metric). We leverage this central limit theorem to prove a stronger but more specific central ... more >>>

In this paper, we construct pseudorandom generators for the class of \emph{combinatorial sums}, a class of functions first studied by \cite{GMRZ13}
and defined as follows: A function $f: [m]^n \rightarrow \{0,1\}$ is said to be a combinatorial sum if there exists functions $f_1, \ldots, f_n: [m] \rightarrow \{0,1\}$ such that
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In this work we ask the following basic question: assume the vertices of an expander graph are labelled by $0,1$. What "test" functions $f : \{ 0,1\}^t \to \{0,1\}$ cannot distinguish $t$ independent samples from those obtained by a random walk? The expander hitting property due to Ajtai, Komlos and ... more >>>