It has recently been suggested (Lissauer and Backman, 1984; Eggleton and Pringle, 1985) that the secondary mass within the Epsilon Aurigae disk is not a single object but an embedded binary. Lissauer and Backman pointed out that this idea would help greatly to account for its low ratio of luminosity to mass, while Eggleton and Pringle argued in addition that the system's evolution could be much better understood in terms of such a configuration. They also noted that a central opening in a thin

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... isk, which was proposed by one of us (Wilson, 1971) as a means to produce certain unusual features of the eclipse, can be accounted for quite naturally if the disk has a binary at its center. With such an embedded binary, circular orbits will be impossible for particles inside a critical radius, leading to an effective viscosity which will cause disk material to spiral inward.