In august, Stephen Hawking the famous theoretical physicist suggested that he and some colleagues were working on solving the black hole information paradox. This paradox seeks to explain what happens to matter that gets destroyed by a black hole, which contradicts Einsteins’s general theory of relativity which states that matter should be fundamentally conserved, based on our understanding of quantum mechanics.
That paper has finally been published and the solution appears to be black hole “hairs”. These hairs form on the event horizon, making a two-dimensional holographic imprint of what has been engulfed by the black hole. The paper claims that these hairs are provable and their existence could win Hawking a Nobel Prize.
The Black Hole Paradox
The issue is that black holes contradict the general theory of relativity. According to our understanding of gravity and how it interacts with everything in the universe, everything that crosses the event horizon of a black hole is lost forever, even light.
In the 70s, Hawking proposed “virtual particles” that exist and don’t exist and annihilate each other when they come in contact with each other, unless they are on either side of a black hole’s event horizon. In this scenario, one particles gets consumed by the black hole and the other radiates away into space.
“The escaping radiation steals energy from the black hole as it departs, so that the black hole loses mass over time. It eventually evaporates out of existence,”says Powell. “According to Hawking’s calculations, the lingering radiation – the only trace of a vanished black hole – contains no useful information about how the black hole formed and what it ate.”
According to what Hawking proposes, when a black hole disappears, the information is lost forever. But, quantum mechanics says that can not happen because information can never be lost.
Fast forward to 1973 and John Wheeler was created with “black holes have no hair” sparking debate if black holes are bald and featureless or had ‘hair’ thus features.
Hair Versus No Hair Debate
If black holes are bald, that are essentially all the same, no matter what information they have consumed. They all would have the same mass, electric charge and angular momentum.
If the do have ‘hair’ as Michael Byrne describes “minute deformities in space-time” then we can learn from each black hole including what it has consumed.
Hawking has been on the hair side for a long time and now says he can solve the black hole information paradox.
“I propose that the information is stored not in the interior of the black hole as one might expect, but on its boundary, the event horizon,” Hawking said at a conference back in August 2015. “The message of this lecture is that black holes ain’t as black as they are painted. They are not the eternal prisons they were once thought. Things can get out of a black hole both on the outside and possibly come out in another universe.”
The team of Malcom J Perry and Andrew Strominger and Hawking claim they have concrete provable steps that explain how information can escape a black hole after being consumed.
“We show that when a charged particle goes in, it adds a soft photon to the black hole. So it adds ‘hair’ to the black hole,” Strominger told Seth Fletcher at Scientific American.
The concept is that as charged particles cross the event horizon, they leave behind a two-dimensional holographic imprint on it. While the physical components of the object are gone, its blueprint remains.
While we knew about the concept in August, the publication allows for peer review of their findings. While it is early, some detractors are already pointing to an incomplete explanation.
“No one has yet reported a mistake in the calculations, but concerns have begun to pop up that the theory is at best incomplete. Sabine Hossenfelder of the Nordic Institute for Theoretical Physics questions how much information the proposed soft hair could encode. She also points out that the paper does not explain how the hairs, which would disappear with the black hole once it evaporated, would transfer their information to the radiation that remains.”
- BlackHole: "BlackHole" by XMM-Newton, ESA, NASA - http://web.archive.org/web/20100416132936/http://www.gsfc.nasa.gov/topstory/20011015blackhole.html (direct link)http://earthsky.org/space/comparing-theory-to-observation-in-eating-habits-of-giant-black-holes (direct link). Licensed under Public Domain via Commons
- sygnux-black-hole: Chandra X-Ray Observatory, NASA