Prediction of Cosmological Constant $\Lambda$ In Veneziano Ghost Theory of QCD$^{*}$

TL;DR

This paper estimates the cosmological constant using Veneziano ghost theory of QCD, incorporating nonlocal quark condensates, and finds results aligning well with observations, advancing understanding of vacuum energy in cosmology.

Contribution

It introduces a method to estimate the cosmological constant using nonlocal quark condensates within Veneziano ghost theory, improving agreement with observed values.

Findings

Using Dyson-Schwinger equations, the local quark condensate matches accepted values.

Incorporating nonlocal condensates yields a cosmological constant consistent with observations.

Results support the relevance of nonlocal effects in QCD vacuum contributions to cosmology.

Abstract

Based on the Veneziano ghost theory of QCD, we estimate the cosmological constant $\Lambda$, which is related to the vacuum energy density, $\rho_{\Lambda}$, by $\Lambda = 8\pi G \rho_{\Lambda}$. In the recent Veneziano ghost theory $\rho_{\Lambda}$ is given by the absolute value of the product of the local quark condensate and quark current mass:$\rho_{\Lambda} = \frac{2N_{f}H}{m_{\eta'}}c |m_{q}<0|:\bar{q}q:|0>|$. By solving Dyson-Schwinger Equations for a dressed quark propagator, we found the local quark condensate $<0|:\bar{q}q:|0> \simeq -(235 MeV)^{3}$, the generally accepted value. The quark current mass is $m_{q} \simeq$ 4.0 Mev. This gives the same result for $\rho_{\Lambda}$ as found by previous authors, which is somewhat larger than the observed value. However, when we make use of the nonlocal quark condensate, $<0|:\bar{q}(x)q(0):|0>= g(x)<0|:\bar{q}q:|0>$, with g(x) estimated from our previous work, we find $\Lambda$ is in a good agreement with the observations.