3 problems

Let $\mu$ be a spectral singular measure, and let a spectrum be a discrete set of frequencies whose exponential functions form an orthonormal basis for $L^2(\mu)$. The Beurling dim…

Velani's conjecture. If

Non-frame-spectrality conjecture for $\mu_4+\mu_8$. The measure $\mu_4+\mu_8$ is not frame-spectral.