Relativistic wetting effects for sessile drops

Relativistic wetting of flat and rough substrates is treated and the transformation of the contact angle is derived. Concepts of hydrophilicity and hydrophobicity are discussed from relativistic point of view. The sign of the spreading parameter demonstrates relativistic invariance, whereas the notions of hydrophilicity and hydrophobicity are not relativistically invariant and depend on the velocity of the reference frame. Relativistic wetting of rough surfaces is also discussed.