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Suppose $X_1, ... , X_{n+1}$ are $n$ i.d.d. random points in $\mathbb{R}^n$ with distribution $N(0, I)$ (multivariate normal with zero mean and identity covariance matrix). Suppose $C$ is the convex hull of $X_1, … , X_{n+1}$. It is not hard to see, that $C$ is almost surely an $n$-dimensional simplex. My question is - what the asymptotic of it’s expected $n$-dimensional Lebesgue measure as $n \to \infty$?

Note, that the explicit computation of the values of that sequence seems to be quite hard in general:

For $n = 1$ (the easiest case) the expectation is $\frac{2}{\sqrt{\pi}$. For $n = 2$ it can be represented as an integral using Heron’s formula, but I am too lazy to explicitly calculate it. How to obtain the exact numbers for higher dimensions, is a complete mystery to me…

However, I am interested not in exact values, but in asymptotic for $n \to \infty$ (and, unfortunately, currently have no idea how to get it).

Chain Markov
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  • Using the fact that the volume is a det of a difference matrix (https://en.wikipedia.org/wiki/Simplex#Volume), it suffices to just find the det of a random gaussian matrix which has been studied before such as https://arxiv.org/pdf/1112.0752.pdf and references inside. – Sandeep Silwal Feb 17 '20 at 15:23
  • I answered this question here a few days ago. – user125932 Feb 22 '20 at 08:15

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