  High temperature superconductors are strongly coupled systems which present a
complicated phase diagram with many coexisting phases. This makes it difficult
to understand the mechanism which generates their singular transport
properties. Hydrodynamics, which mostly relies on the symmetries of the system
without referring to any specific microscopic mechanism, constitutes a
promising framework to analyze these materials. In this paper we show that in
the strange metal phase of the cuprates, a whole set of transport coefficients
are described by a universal hydrodynamic framework once one accounts for the
effects of quantum critical charge density waves. We corroborate our
theoretical prediction by measuring the DC transport properties of Bi-2201
close to optimal doping, proving the validity of our approach. Our argument can
be used as a consistency check to understand the universality class governing
the behavior of high temperature cuprate superconductors.
