A construction of Kakeya Sets in Arbitrary Dimension

We construct Kakeya sets in arbitrary dimension $d\ge 2$, generalizing the classical Perron tree construction beyond dimension $2$. The Kakeya sets we construct have $\delta$-neighbourhood of volume at most $C\mathrm{\mid }\log \delta {\mathrm{\mid }}^{-(d-1)}$, which improves on previously known constructions, and which is conjecturally optimal. We further derive consequences for the $L^p$-boundedness of radial Fourier multipliers in terms of Besov spaces with logarithmic smoothness.