Instability of warped discs

Understand

Accretion discs are generally warped.

• If a warp in a disc is too large, the disc can `break' apart into two or more distinct planes, with only tenuous connections between them.
• Further if an initially planar disc is subject to a strong differential precession, then it can be torn apart into discrete annuli that precess effectively independently.
• In previous investigations, torque-balance formulae have been used to predict where and when the disc breaks into distinct parts.