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ABSTRACT. While attempts to unify certain classes of AGN using orientation and environmental effects have been successful, it is widely recognized that intrinsic properties of the accreting black hole system also must play a role in determining the appearance of such an object. In addition to mass and accretion rate, the angular momentum (or spin) of the black hole can play a crucial role in determining the power of a relativistic jet that is generated by magnetohydrodynamic acceleration near the hole. In this paper a scenario is presented, based on accretion theory and recent models of MHD jet production, in which the primary (although not only) parameter differentiating between radio loud and quiet objects is the black hole spin, and that determining quasar vs. radio galaxy is the accretion rate. A surprising number of desirable features result from these simple concepts and the accompanying equations. In addition, there are several testable predictions that can determine whether this grand unification scheme has further merit.

Table of Contents

INTRODUCTION: HEREDITY vs. ENVIRONMENT

THE ACCRETION PARADIGM: EFFECTS OF BLACK HOLE MASS AND ACCRETION RATE

Observational and Theoretical Evidence for the Accretion Paradigm

Observations Explained

THE SPIN PARADIGM: EFFECTS OF BLACK HOLE ROTATION

Theoretical Arguments for the Spin Paradigm

General Relativistic Simulations of Magnetized Disks in Kerr Geometry

Observational Advantages of the Spin Paradigm

AN EXAMPLE GRAND UNIFICATION SCHEME - OBSERVATIONAL PREDICTIONS

DISCUSSION AND CONCLUSIONS

REFERENCES