We take a null hypersurface (causal horizon) generated by a congruence of null geodesics as the boundary of the Doran - Lobo - Crawford spacetime to be the place where the Brown - York quasilocal energy is located. The components of the outer and inner stress tensors are computed and depend on time and the impact parameter $b$ of the test particle trajectory. The spacetime is a solution of Einstein's equations with an anisotropic fluid as source.

A nonvanishing value for the Rindler horizon energy is proposed, by an analogy with the "near horizon" Schwarzschild metric.We show that the Rindler horizon energy is given by the same formula $E = alpha/2$ obtained by Padmanabhan for the Schwarzschild spacetime, where $alpha$ is the gravitational radius.

By an analogy with the "Rindler horizon" Schwarzschild metric, a nonvanishing value for the Rindler horizon energy is proposed. We show that the energy is given by the same formula obtained by Padmanabhan for the Schwarzschild spacetime, in terms of the gravitational radius.

Using Padmanabhan's prescription, the entropy of the horizon of the Hawking wormhole written in spherical Rindler coordinates is computed. We found that the surface gravity of the horizon is constant and equals the proper acceleration of the Rindler observer. The entropy expression is similar with the Kaul-Majumdar one for the black hole entropy, including logarithmic corrections.

A possible connection between the energy W of the vacuum fluctuations of quantum fields and gravity in "empty space" is conjectured in this paper using a natural cutoff of high momenta with the help of the gravitational radius associated to the vacuum region considered. Below some critical length $L = 1 mm$ the pressure is one third of the energy density but above $1 mm$ the equation of state corresponds to the dark energy one. When the Newton constant