Understanding the "anti-kick" in the merger of binary black holes

Unequal arm space-borne gravitational wave detectors

Unequal Mass Binary Black Hole Plunges and Gravitational Recoil

Unexpectedly large surface gravities for acoustic horizons?

Unfashionable observations about three dimensional gravity

Unfinished History and Paradoxes of Quantum Potential. I. Non-Relativistic Origin, History and Paradoxes

Unfinished History and Paradoxes of Quantum Potential. II. Relativistic Point of View

Unfinished revolution

Unfolded Description of $AdS_4$ Kerr Black Hole

Unification of Dark Matter and Dark Energy in a Modified Entropic Force Model

Unification of gravity and electromagnetism revisited

Unification of Gravity and Yang-Mills Theory in (2+1)-Dimensions

Unification of gravity, gauge fields, and Higgs bosons

Unification of inflation and cosmic acceleration in the Palatini formalism

Unification of Weak and Gravitational Interactions Stemming from Expansive Nondecelerative Universe Model

Unified Analysis of Cosmological Perturbations in Generalized Gravity

Unified approach to study quantum properties of primordial black holes, wormholes and of quantum cosmology

Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models

Unified Field Theory From Enlarged Transformation Group. The Consistent Hamiltonian

Unified Field Theory From Enlarged Transformation Group. The Covariant Derivative for Conservative Coordinate Transformations and Local Frame Transformations