4 problems

Universal optimality conjecture for lifted ETFs. The following configurations minimize the $p$-frame potential $\operatorname{FP}_{p,d+1,d}$: when $p\in(p_{k-1},p_k]$, the $L_k^d$…

Let $D$ and $N$ be positive integers with $N>2D>2$, and let a real $\operatorname{ETF}(D,N)$ denote a real equiangular tight frame of $N$ vectors in dimension $D$. Call $(D,N)$ pos…

Let $D$ and $N$ be positive integers with $N>2D>2$, and let an $\operatorname{ETF}(D,N)$ denote a complex equiangular tight frame of $N$ vectors in dimension $D$. Call $(D,N)$ posi…

Real flat ETF Hadamard conjecture. Every real flat ETF is Hadamard.