Most Detailed Ever Simulations Of Black Hole Solve Longstanding Mystery

Black Hole
Name
Institution
Due Date
Black Hole
Question 1

Media Article

Research Article

Title of Article

Most-detailed-ever simulations of black hole solve longstanding mystery

Bardeen–Petterson alignment, jets, and magnetic truncation in GRMHD simulations of tilted thin accretion discs

Source of Article

https://news.northwestern.edu/stories/2019/06/most-detailed-ever-simulations-of-black-hole-solve-longstanding-mystery/

https://academic.oup.com/mnras/article/487/1/550/5420428

Date of Publication

June 06, 2019

26 April 2019

Was the research done by the author of the article?

No

Yes

Where are the Authors from (if information is available)?
Give the name and location of their place of work.

Amanda Morris - Media Relations Staff, Northwestern University

M Liska - Anton Pannekoek Institute for Astronomy, University of Amsterdam
A Tchekhovskoy - Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA), Physics & Astronomy, Northwestern University
A Ingram - Department of Physics, Astrophysics, University of Oxford
M van der Klis - Anton Pannekoek Institute for Astronomy, University of Amsterdam

Question 2
The media article indicates that an international tea, has made the highest resolution of the black hole possible. Using the simulation, it is possible to prove theoretical predictions regarding the nature of accretion disks. Researchers from three universities established that the inner-most part of an accretion disk is aligned with its black hole’s equator. This outstanding discovery solves a mystery that has existed since 1975. During this time, physicists Jim Bardeen and Jacobus Petterson proposed that a spinning black hole would lead to the inner part of a titled accretion disk to be aligned with its black hole’s equatorial plane. This discovery has taken long considering that scientists have been trying to establish the authenticity of the Bardeen-Petterson effect. The previous simulations did not go beyond providing an approximation of the impact of the turbulence.
In the research article, Liska et al. (2018) provides that the prevalent surrounding accreting black holes, thin discs are problematic to solve, especially in numerical simulations. Often, the disc and black hole angular vectors become misaligned. In such a case, it is necessary to employ adaptive meshes which follow the disc proper while it is moving through the computational grind. The results indicate that while the outer region of an accretion disk remains tilted, the inner region aligns with the black hole. Furthermore, there is a warp that links both the inner and outer regions. By thinning accretion disk to an unparalleled degree and having magnetic turbulence that causes the acceptation, it was possible to solve the mystery.
Question 3
The media article is divided into various sections. The first one is the introduction, which includes research findings. Here, the author provides an overview of the mystery that has existed since 1975 following the work of Bardeen and Petterson. The author then goes ahead and presents the outcome ...