Imaging black hole like listening to broken piano, says scientist

Testifying before Congress, US scientist Katie Bouman suggested the technology developed by the black hole project could have pr
Testifying before Congress, US scientist Katie Bouman suggested the technology developed by the black hole project could have practical applications in the fields of medical imaging, seismic prediction and self-driving cars

US computer scientist Katie Bouman, who became a global sensation over her role in generating the world's first image of a black hole, has described the painstaking process as akin to listening to a piano with broken keys.

Testifying before Congress on Thursday, the postdoctoral fellow at the Harvard Smithsonian Center for Astrophysics also suggested the technology developed by the project could have in the fields of medical imaging, seismic prediction and self-driving cars.

A photo released last month of the star-devouring monster in the heart of the Messier 87 (M87) galaxy revealed a dark core encircled by a flame-orange halo of white hot plasma.

But since M87 is 55 million away, "This ring appears incredibly small on the sky: roughly 40 microarcseconds in size, comparable to the size of an orange on the surface of the Moon as viewed from our location on Earth," said Bouman.

The laws of physics would require a the size of our entire planet to view it: an impossible proposition.

The Event Horizon Telescope (EHT) Collaboration instead spent over a decade building an Earth-sized computational telescope that combined signals received by various telescopes working in pairs around the world.

However, since there are a limited number of locations, the telescopes are able to capture only some frequencies, leaving large gaps in information.

"As an analogy, you can think about the measurements the EHT makes a bit like notes in a song; each measurement corresponds to the tone of one note, " said Bouman.

"Observing the black hole with the Event Horizon Telescope is a bit like listening to a song being played on a piano with over half of its keys broken."

The approach led to numerous gaps that could be filled with infinite possibilities consistent with the data.

"But just as your brain may still be able to recognize a song being played on a broken piano if there are enough functioning keys, we can design algorithms to intelligently fill in the EHT's missing information to reveal the underlying black hole image," she concluded.

Avoiding human bias

While the images were captured in 2017, the final result had to be independently validated by four EHT teams working around the world to avoid shared human bias.

The four images they produced varied slightly, but they all contained the same basic structure.

"Seeing these images for the first time was truly amazing and one of my life's happiest memories," recalled Bouman, who maintained a broad smile throughout her testimony.

The final image released to the public on April 10 this year was a composite of the four images further tuned by algorithms designed to eliminate human preferences.

Bouman said she first began working on the EHT as a graduate student studying computer vision at MIT and found the problem shared striking similarities with work she had done on brain imaging based on limited data from an MRI scanner.

"Thus, although the project was well outside of my core area, and I had no background in astrophysics let alone black holes, I hoped that I might be able to make a difference."

She also hailed the early-career scientists who had come to the project from various fields and ranged from post doctorates to undergraduates whose work was vital to the project.

"However, like , many early-career scientists with significant contributions often go unseen," she said.

Explore further

Scientist superstar Katie Bouman designed algorithm for black hole image

© 2019 AFP

Citation: Imaging black hole like listening to broken piano, says scientist (2019, May 16) retrieved 14 October 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

May 16, 2019
In search of black holes and dark matter astrophysicists are relying on indirect observations. It would seem that the measurement of the event horizon of a black hole directly would be a direct evidence. However, by the nature of a horizon, any real measurement of the event horizon will be indirect. The Event Horizon Telescope will get picture of the silhouette of the Sgr A* which is due to optical effects of spacetime outside of the event horizon. The result will be determined by the simple quality of the resulting image that does not depend on the properties of the spacetime within the image. So, it will be also indirect and an existence of BH is a hypothesis.

May 16, 2019
Well, i think the simplest way to consider this subject, using real-world experience.

Would be to to find a crater on the Earth's surface.
Yhen ferret out the evidence for what use to occupy the empty space.
Utilizing evidence left behind by the explosive event.
& the resulting debris surrounding the empty space.

Then reversing the whole process as a model.
To more accurately express that a BH/EH Stygian Oubliette is the opposite of an explosion.

Rather it is what happens when a sufficient amalgamation of gravitational attractants occur.

May 17, 2019
Explore a black hole and its complementary event horizon by reviewing an alternative theory of the universe from a more 4th dimensional perspective. This concept was previously approached in the book, 'The Evolutioning of Creation: Volume 2', copyrighted in 2011. As the predominant condition of the universe is a combination of dark energy and dark matter (i.e., massless matter or negative mass density), then the existence of our universe [or positive mass density] is more of an intrusion upon this norm. Such is it that positive density mass (i.e., baryonic mass) provides for a displacement effect, which is expressed as if the positive mass has intruded upon the inertial condition of the space-time continuum.

You can peak your interest for answers to the makeup and consistency of the black hole from the perspective of the science fiction novel, 'Shadow-Forge Revelations'. As science fiction imitates science theory, this novel discusses how dark matter interplays with this concept.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more