Cardinal invariants on universally null sets

We investigate the cardinal invariants on universally null sets. In particular, we prove $\mathfrak{b}<\mathrm{cof}(\mathcal{U}\mathcal{N})$ and $\mathrm{non}(\mathcal{N})=\mathrm{non}(\mathcal{U}\mathcal{N})<\mathrm{cof}(\mathcal{U}\mathcal{N})$ in $\mathsf{Z}\mathsf{F}\mathsf{C}$. Also, assuming $\mathrm{add}(\mathcal{N})=\mathfrak{c}$, we prove $\mathrm{cof}(\mathcal{U}\mathcal{N})={\mathfrak{d}}_{\mathfrak{c}}$ by adapting Yorioka’s technique. Moreover, we prove the consistency of $\mathrm{add}(\mathcal{U}\mathcal{N})<\mathrm{cov}(\mathcal{U}\mathcal{N})<\mathrm{non}(\mathcal{U}\mathcal{N})<\mathrm{cof}(\mathcal{U}\mathcal{N})$.