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High-resolution neutron spectroscopy on ${\mathrm{Ce}}_2{\mathrm{Hf}}_2{\mathrm{O}}_7$reveals a correlated state characterized by distinct dipolar scattering signals—quasielastic and inelastic contributions consistent with ‘photon’ and ‘spinon’ excitations in quantum spin ice. These signals coexist with weak octupolar scattering. Fits of thermodynamic data using numerical methods indicate a dominant octupolar exchange, $J_x$or $J_y$, with substantial dipolar $J_z$and minute dipole-octupole $J_{xz}$couplings. The $J_{xz}$value is corroborated by an independent fit of the neutron scattering amplitude balance between dipolar and octupolar ‘photon’ contributions, highlighting its importance to understand neutron scattering results in this family. ${\mathrm{Ce}}_2{\mathrm{Hf}}_2{\mathrm{O}}_7$enriches the landscape of dipole-octupole pyrochlore physics, and reveals a ‘quantum multipolar liquid’ where hybrid correlations involve multiple terms in the moment series expansion, opening questions regarding their intertwining and hierarchy in quantum phases. 

We investigate the correlated state of Ce2Hf2O7 using neutron scattering, finding signatures of correlations of both dipolar and octupolar character. A dipolar inelastic signal is also observed, as expected for spinons in a quantum spin ice (QSI). Fits of thermodynamic data using exact diagonalization methods indicate that the largest interaction is an octupolar exchange, with a strength roughly twice as large as other terms. This hierarchy of exchange interactions - far from a perturbative regime but still in the octupolar QSI phase - rationalises observations in neutron scattering, which illustrate the multipolar nature of degrees of freedom in Ce3+ pyrochlores.