We know that there exists an underlying background energy in space throughout the entire Universe, called vacuum energy and this is a special case of zero-point energy that relates to the quantum vacuum. Wikipedia is saying about its current measured value:
Using the upper limit of the cosmological constant, the vacuum energy of free space has been estimated to be $10^{−9}$ Joules ($10^{-2}$ ergs), or $\sim5$ GeV per cubic meter.$^{[3]}$
I also know that there is some discrepancy about the measured value of this vacuum energy density and the current value of cosmological constant, known as Cosmological Constant Problem:
Depending on the Planck energy cutoff and other factors, the quantum vacuum energy contribution to the effective cosmological constant is calculated to be as little as $50$ and as much as $120$ orders of magnitude greater than observed,...
QUESTION:
- Associated with this energy density, does there exist any pressure (that may be thermodynamic or mechanical or whatever) in the vacuum [which may be termed as "(quantum) vacuum pressure"]?
- If yes, then what will be its expression for a general case?
My Attempt(s): In this paper on "Quantum vacuum pressure on a conducting slab", the author has found that the vacuum pressure on each surface of a conducting slab (in connection to the Casimir experiments) is, $P = \dfrac{\hbar \omega_p^4}{24 \pi^2 c^3}$ , where $\omega_p = \sqrt{\dfrac{N_e e^2}{m_e \epsilon_0}}$.
But this expression is not for a general case. I'm seeking for a comparatively general one. Is there anything so?