A conditional arithmetic obstruction to the prime numbers as a spectrum of a probability measure

Abstract

Let $\Pp=\{2,3,5,7,\ldots\}$ denote the set of prime numbers. We prove that if every sufficiently large positive even integer can be represented as a difference of two primes, then there is no Borel probability measure $μ$ on $\R$ for which \(\left\{e^{2πi p x}:p\in\Pp\right\}\) is an orthonormal basis of $L^2(μ)$. In particular, under the Polignac conjecture, the prime numbers $\Pp$ cannot be a spectrum (i.e., the set of frequencies of an exponential orthonormal basis) of any probability measure on $\R$.