Quirks and Quarks16:47UK science star Brian Cox’s new book explores how we might live in a black hole
Black hole research in the last few years is revealing a tantalizing new view of the very nature of time and space.
In his new book, physicist and science communicator Brian Cox explores how the new physics might help us reconcile the fundamental clash of principals stemming from our understanding of gravity at a cosmological scale and the physics of the minutia that underlies it, quantum theory.
You say right in the title of your book that black holes are the key to understanding the universe. How has that become even more true in recent years?
Beginning with Stephen Hawking’s work in the 1970s, it was understood that black holes are not only interesting from an astrophysical perspective, but they actually set up a fundamental clash of principle between the two great pillars of 20th and 21st century physics, which are Einstein’s theory of gravity and quantum theory.
In his new book, physicist Brian Cox explores how black holes are like the Rosetta stones to a deeper understanding of not only our universe, but the very nature of reality itself. (Harper Collins)
Hawking discovered that when you put those two frameworks together, there’s a prediction, which is black holes have a temperature. Now that was a remarkable discovery because temperature was just a thing you could measure on a thermometer, but it was really only fully understood when we knew that everything is made of atoms.
Temperature tells you how fast the component parts of something are jiggling around and moving.
Contrast that with the description of a black hole. A black hole in Einstein’s theory is just a distortion in the fabric of space-time where even light itself cannot escape. All it is geometry. It doesn’t appear to have any moving parts at all, so immediately back in the 1970s, there was a sign that there may be something deeper to black holes.
A more modern version of Hawking’s discovery is that the temperature of a black hole has to do with the information it can store or hide from us.
When you say information, what do you mean?
Literally bits of information. So Jacob Beckenstein calculated how much information ablack hole contains. And he found an astonishing result: the amount of information — in bits literally — that the black hole stores is equal to the surface area of the event horizon of the black hole.
Theoretical physicist Stephen Hawking’s 1974 theory about black holes having a temperature kickstarted what has become a quantum revolution in astrophysics. (Matt Dunham/Associated Press)
The event horizon is the point of no return.
Yes, the point of no return. But remember, it’s just space. For very big black holes, like the sort you find at the centres of galaxies, you could fall through it and you wouldn’t notice a thing.
When you say bits of information, I usually think of bits that are used in terms of computer science to describe a zero or a one that encodes information. What are the bits of the event horizon in a black hole?
Well, yeah, so that’s what you’re supposed to think. What are they? We don’t know. We seem to know how big they are, so how many pixels there are.
But it’s very strange for two reasons. One is that we’re just talking about space for a start, so what do we mean by a pixel of space? And secondly, this idea that somehow the amount of information is proportional to the surface area.
In this artist’s rendering, a star makes its closest approach to the supermassive black hole at the center of the Milky Way. (Nicolle R. Fuller/National Science Foundation/Reuters)
We say that nothing can come out of a black hole and yet, Stephen Hawking is famous for his Hawking radiation, which does come out of a black hole. And if it has temperature, that’s also something coming out of a black hole. Take me through that.
Stephen Hawking uses an analogy in his 1974 paper to describe what’s happening. You can picture the vacuum of space. If you could imagine zooming in and slowing time down with some great microscope, you could picture the vacuum of space as not being empty, as being filled with particles fizzing in and out of existence all the time.
Imagine that a pair of these particles, which would have come into existence and disappeared again, they can be configured such that one’s on the inside of the horizon and one is on the outside of the horizon.
So that means that the one on the inside is not coming out, but the upshot is the one on the outside that would have gone back and re-merged with its partner, essentially giving its energy back to the vacuum, can be made real and can escape into space.
The supermassive black hole in the galaxy M87 was originally photographed by the Event Horizon Telescope collaboration in 2019, left, and was spruced up in a 2023 image generated by the PRIMO algorithm, right. (Medeiros et al. 2023/Reuters)
Not that I want to throw your book into a black hole, but what would happen to it and the information that it contains if I tossed it in?
As viewed from the outside, you can picture the book as being completely incinerated as it approaches the horizon, with all the bits of information being smeared around.
You could almost imagine this kind of hot atmosphere of the black hole, which somehow contains the information and re-radiates it out into the universe again. And that would be essentially what happens when you burn the book.
A glowing stream of material from a star is disrupted as it was being devoured by a supermassive black hole surrounded by a ring of dust and illuminated by high-energy radiation. (Caltech/JPL/NASA)
So no problem, except that according to Einstein’s theory of general relativity, you can also ask the question, what does that look like from the perspective of the book or an astronaut falling in? Einstein’s theory is unequivocal. From the perspective of the book or the astronaut, you can fall across the horizon into the interior of the black hole.
Now you have two descriptions of what happened from different perspectives and both are correct.
You said at the beginning of our conversation that this new idea of reality in a black hole is part black hole geometry and part quantum physics. How do we tie those two together to bring us to a new understanding of reality?
So we had these disparate ideas, right? The black hole can somehow store information and it’s something to do with the surface area of the black hole. And then we have this idea that there are different pictures of what happened and that they can both be true at the same time.
The modern view is that all these different pictures are trying to tell us something. And what they’re trying to tell us seems to be that space and time are not fundamental properties of the universe, but they emerge from a deeper theory. And that theory seems to be quantum theory which does not have space and time in it.
In this illustration, a supermassive black hole pulls a stream of gas off a star that passes too close. (Chris Smith/USRA/GESTAR/NASA’s Goddard Space Flight Center)
So, the black holes, as we say in the book, they’re like Rosetta stones in the sense that they’re forcing us to discover that there are different descriptions of our universe. One of them is the description of Einstein and then there’s another description, which just looks like some kind of quantum theory, some kind of building blocks of the universe that are entangled together.
And so quantum mechanics allows for this property where things can be related to each other — connected together, if you like. And out of that emerges this other description that we’re familiar with. So it’s almost like the black hole is a naturally occurring object that forced us to glimpse a deeper description of our reality.
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
