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arXiv · 2602.03058

Moments of sums of exponentials, beyond CHS

Silouanos Brazitikos·Colin Tang·Tomasz Tkocz
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Abstract

We establish a sharp lower bound on the $L_p$-norm of sums of independent exponential random variables with fixed variance, for $p \geq 2$, thus extending Hunter's positivity theorem (1976) for completely homogeneous polynomials. We determine the exact regime of $p$ where such sums enjoy Schur-monotonicity.

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Silouanos Brazitikos, Colin Tang, Tomasz Tkocz. 2026-02-03. Moments of sums of exponentials, beyond CHS. https://arxiv.org/abs/2602.03058

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