Do planets without a solid surface precess?

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SUMMARY

The discussion centers on the precession of black holes, specifically whether they exhibit precession similar to that of planets. A recent study published in the Monthly Notices of the Royal Astronomical Society indicates that the accretion disk surrounding a black hole applies torque, leading to inevitable precession of the black hole's spin axis. The conversation also touches on the concept of axial precession in Earth, highlighting that non-spherical asymmetry is necessary for precession to occur. The question arises regarding whether gaseous or liquid planets, lacking a solid structure, would also experience precession.

PREREQUISITES
  • Understanding of black hole physics and accretion disks
  • Familiarity with general relativity and the concept of gravity as a curvature of spacetime
  • Knowledge of axial precession and its mechanics
  • Basic grasp of astrophysical phenomena related to celestial bodies
NEXT STEPS
  • Read the study on black hole precession published in the Monthly Notices of the Royal Astronomical Society
  • Explore the mechanics of axial precession in celestial bodies
  • Investigate the properties of accretion disks and their influence on black hole dynamics
  • Examine the behavior of gaseous and liquid planets in astrophysical contexts
USEFUL FOR

Astronomers, astrophysicists, and students of physics interested in black hole dynamics, precession phenomena, and the behavior of celestial bodies in gravitational fields.

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Do black holes precess? I added some marks to a picture of quasar 3c175... can the highlighted distortion of the jet be interpreted as black hole precession?

3c175.gif
 
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Precession will occur when an external force applies angular momentum to a spinning object that is not aligned with that objects spin axis. Accretion disks are, in general, not aligned exactly with the black holes spin axis - but the material becomes aligned before it nears the even horizon.

This process was modeled in a study just released this month:
https://academic.oup.com/mnras/article/487/1/550/5420428
(suggest you skip to "RESULTS")

According to the authors, the acretion disk does "torque" the black hole. So it would seem inevitable that the black holes spin axis would precess.
 
Very interesting. I was reading about axial precession on the Earth:

For precession, this tidal force can be grouped into two forces which only act on the equatorial bulge outside of a mean spherical radius. This couplecan be decomposed into two pairs of components, one pair parallel to Earth's equatorial plane toward and away from the perturbing body which cancel each other out, and another pair parallel to Earth's rotational axis, both toward the ecliptic plane.[20] The latter pair of forces creates the following torquevector on Earth's equatorial bulge:[4]

\overrightarrow {T}={\frac  {3Gm}{r^{3}}}(C-A)\sin \delta \cos \delta {\begin{pmatrix}\sin \alpha \\-\cos \alpha \\0\end{pmatrix}}

https://en.wikipedia.org/wiki/Axial_precession

If I understand correctly, the Earth requires non-spherical asymmetry for its precession to occur, is a black hole thought to be the same in this regard?
 
A spinning black hole is not spherically symmetric, no. A non-rotating one is.

Don't assume precession of a black hole has anything to do with forces, though. Gravity is not a force in general relativity.
 
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