This paper brings into attention a possible logarithmic connection between Einstein's constant and the fine-structure constant, based on a hypothetical electro-gravitational resistivity of vacuum: we also propose a zero-energy hypothesis (ZEH) which is essentially a conservation principle applied on zero-energy that mainly states a general quadratic equation having a pair of conjugate mass solutions for each set of coefficients, thus predicting a new type of mass "symmetry" called here "mass conjugation" between elementary particles (EPs) which predicts the zero/non-zero rest masses of all known/unknown EPs to be conjugated in boson-fermion pairs; ZEH proposes a general formula for all the rest masses of all EPs from Standard model, also indicating a possible bijective connection between the three types of neutrinos and the massless bosons (photon, gluon and the hypothetical graviton), between the electron/positron and the W boson and predicting two distinct types of neutral massless fermions (modelled as conjugates of the Higgs boson and Z boson respectively) which are plausible candidates for dark energy and dark matter. ZEH also offers a new interpretation of Planck length as the approximate length threshold above which the rest masses of all known elementary particles have real number values (with mass units) instead of complex/imaginary number values (as predicted by the unique quadratic equation proposed by ZEH). Main sources: http://www.journalpsij.com/index.php/PSIJ/article/view/30191 http://www.journalpsij.com/index.php/PSIJ/article/view/30191/56646 http://sdiarticle4.com/review-history/57825 (open peer-review history)