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metastable
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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?
Do planets without a solid surface precess?
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In summary, black holes can precess when an external force applies angular momentum to the spinning object, such as an accretion disk not aligned with the black hole's spin axis. This was recently studied and modeled in a published article. The Earth's precession is caused by tidal forces, but in general relativity, gravity is not considered a force. A spinning black hole is not spherically symmetric and a non-rotating one does not precess. It is not necessarily due to external forces. Other objects like gaseous or liquid planets can also precess without a cohesive structure to tilt.
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.Scott
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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.
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.
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metastable
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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]
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?
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]
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?
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Ibix
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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.
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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hmmm27
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The pic in colour and NASA description
Would a gaseous or liquid planet also precess ? there being no cohesive structure to tilt.
Would a gaseous or liquid planet also precess ? there being no cohesive structure to tilt.
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Related to Do planets without a solid surface precess?
1. What is precession?
Precession is the phenomenon where the axis of rotation of a spinning object changes direction over time.
2. Do all planets experience precession?
No, not all planets experience precession. Only planets that have an oblate shape (not perfectly spherical) and a non-zero axial tilt will experience precession.
3. How does precession affect a planet without a solid surface?
Precession can affect the rotation and orientation of a planet without a solid surface, such as a gas giant. However, the lack of a solid surface means that there are no fixed points of reference, so the effects of precession may not be as noticeable as on a solid-surfaced planet.
4. What causes precession on a planet?
Precession is caused by the gravitational pull of other bodies, such as the sun and other planets, on a planet's oblate shape and axial tilt. This results in a torque that causes the axis of rotation to slowly change direction.
5. Can precession have any significant impact on a planet's orbit or climate?
Yes, precession can have significant impacts on a planet's orbit and climate. It can affect the distribution of solar radiation and alter the timing and intensity of seasons. It can also cause changes in a planet's orbit over long periods of time.
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