The main parts of this book consist of three long articles that have previously been published by the Galilean Electrodynamics journal during three succeeding years as summer special issues, while the rest of the information concerns a new theory of ether that has been developed. This version of ether is compatible with special relativity theory (SRT), and thus it cannot be considered as an absolute frame of reference. One of the virtues of this book is that many of the novel predictions can be tested in high-tech laboratories; moreover, the book includes some new and strange physical concepts which make the proposed claims rational and plausible. As it is written on the front page, "From the effect of pressure on time dilation to the unified mass-charge equation" is not intended as a gossipy slogan, which sometimes appear in pseudoscientific media or science-fictional books; it is a true motto with a deep and physical bases. However, it is up to the reader to judge the book about whether or not it really does what it sets out to do!Unfortunately, most of the recent theories in physics, with no clear deployment against the main tenets of relativity or quantum mechanics, are inflated in a way to be comprehensively explanatory, whereas there are few or no experimental evidences that support these theories as good descriptions of nature. In the author's view, such theories not only baffle naive minds of unsophisticated readers not to involve themselves with philosophical bases, deceptively pretending that a high level of knowledge is needed for the theories to be correctly understood by confining the erudition seeker into the cage of complicated math forms; they also deteriorate traditional science methodology over the course of time. Nonetheless, density theory (DT) tries to abide by the methodology of the renowned physics giants by founding profound postulates. The first chapter introduces a substantial number of Einstein's general relativity predictions, which are recalculated according to density theory (DT) that validates the theory for the reader. The second chapter uses interesting concepts, some of which present empirically bizarre results that are adduced and have been undisclosed as of yet. In Chapter Three, the authors try to unify mass and electrical charge - one of the oldest and most disputatious physical problems - in the single equation of "mass + rotation = charge" for the very first time in the history of science. For better understanding, the authors have set forth some numerical examples after explaining each novel concept and no complicated mathematical methods beyond common calculus. These are used to make the present book read as an argumentative dissident textbook suitable for a bachelor student in science and engineering, who can easily nourish the endless desire of a curious student/researcher beyond the realm of orthodoxy in frontier physics.
