Think that everything in a black hole gets swallowed up, never to be seen again? Well, you're half right

What happens to the information in a black hole once it disappears? Stephen Hawking thought he knew, betted on it, and lost.

Young people? Nothing but trouble. If you don’t believe the politicians, just look at physicists’ current anguish over the question of what is lost when stuff falls into a black hole. We are now in the middle of a huge crisis of confidence, just because the kids couldn’t keep their ideas to themselves.
 
If you think that stuff in a black hole just gets swallowed up, never to be seen again, you’re half right. The stuff is indeed gone. Yet the information about the stuff can’t be. In the 1970s, a young Stephen Hawking showed that, due to a quirk of quantum theory, black holes don’t just swallow; they also spit. A trail of particles is emitted from a black hole over its lifetime. As a result, the black hole eventually loses so much energy that it evaporates and disappears from the universe. According to Hawking’s theory, those particles contain no information of any kind, so the original information is lost once the black hole disappears.
 
However, a fundamental law of physics states that information can’t be destroyed. In 1997, John Preskill of the California Institute of Technology was so confident that Hawking must be wrong that the pair entered into a bet. That year, a young theorist called Juan Maldacena showed that, as stuff fell in, the information could be caught on the “event horizon”, the spherical surface of a black hole. With the information residing on the event horizon, it isn’t erased from the universe and might eventually leak back out.
 
Maldacena’s work was convincing enough for Hawking to concede. In 2004, he bought Preskill a baseball encyclopaedia (for reasons we won’t go into here) and the bet was considered settled.
 
Then, in 2010, along came the vibrant young mind of Mark Van Raamsdonk. His work has led to the new debate over the “cosmic firewall”. For information on the event horizon to leak back into the universe, there has to be a layer of ultra-high-energy particles – a firewall – just inside the event horizon. Each particle taking information from the event horizon has what Albert Einstein once termed a “spooky” link with a particle in the firewall. The link is called “entanglement” and it means that you can’t fully describe one of the particles unless you have information that resides in the other.
 
The problem is, the nature of Hawking’s original result shows that the particle on the outside of the event horizon also has to be entangled with another particle, one that carried away a little information from the black hole some time in the past. And a single particle can’t share that kind of entanglement with two others. So Maldacena’s idea doesn’t work. The best solution anyone can come up with involves another entanglement, this time between the particle inside the firewall and the particle that left the black hole all that time ago. That particular spooky link resolves the problem because those two entangled particles are actually one and the same.
 
It’s a classic Shakespearean twist. The whole problem has been a case of mistaken identity: the cosmic firewall story is the Twelfth Night of cosmology. However, most physicists don’t like this ending. Resolving all these entanglements stretches credulity too far, they say. The resolution they prefer is to acknowledge that this whole shebang exposes a gaping hole in our understanding of the universe. Maybe, they say, we need to start again.
 
While they scratch their heads and wonder what to do, Hawking could justifiably ask for his encyclopaedia back. If Preskill has any sense of how to play the foiled schemer, he’ll reluctantly hand it over while muttering something about those pesky kids. 
 
Michael Brooks’s “The Secret Anarchy of Science” is published by Profile Books (£7.99) 
In 1997 Hakwing made a bet with John Preskill of the California Institute of Technology - and lost. Photograph: Andrew Burman/Evevine/Contrasto.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 02 September 2013 issue of the New Statesman, Syria: The west humiliated

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The one where she turns into a USB stick: the worst uses of tech in films

The new film Worst Tinder Date Ever will join a long tradition of poorly-thought-through tech storylines.

News just in from Hollywood: someone is making a film about Tinder. What will they call it? Swipe Right, perhaps? I Super Like You? Some subtle allusion to the app’s small role in the plotline? Nope – according to Hollywood Reporterthe film has been christened Worst Tinder Date Ever.

With the exception of its heavily branded title (You’ve Got Gmail, anyone?), Worst Tinder Date Ever follows neatly in the tradition of writers manhandling tech into storylines. Because really, why does it matter if it was a Tinder date? This “rom com with action elements” reportedly focuses on the couple’s exploits after they meet on the app, so the dogged focus on it is presumably just a ploy to get millennial bums on cinema seats.  

Like the films on this list, it sounds like the tech in Worst Tinder Date Ever is just a byword for “modern and cool” – even as it demonstrates that the script is anything but.

Warning: spoilers ahead.

Lucy (2014)

Scarlett Johansson plays Lucy, a young woman who accidentally ingests large quantities of a new drug which promises to evolve your brain beyond normal human limits.

She evolves and evolves, gaining superhuman powers, until she hits peak human, and turns into first a supercomputer, and then a very long USB stick. USB-Lucy then texts Morgan Freeman's character on his fliphone to prove that: “I am everywhere.”

Beyond the obvious holes in this plotline (this wouldn’t happen if someone’s brain evolved; texting a phone is not a sign of omnipotence), USB sticks aren’t even that good – as Business Insider points out: “Flash drives are losing relevance because they can’t compete in speed and flexibility with cloud computing services . . . Flashdrives also can’t carry that much information.”

Star Wars: The Force Awakens (2015)

If you stare at it hard enough, the plotline in the latest Star Wars film boils down to the following: a gaggle of people travels across space in order to find a map showing Luke Skywalker’s location, held on a memory stick in a drawer in a spherical robot. Yep, those pesky flash drives again.

It later turns out that the map is incomplete, and the rest of it is in the hands of another robot, R2-D2, who won’t wake up for most of the film in order to spit out the missing fragment. Between them, creator George Lucas and writer and director JJ Abrams have dreamed up a dark vision of the future in which robots can talk and make decisions, but can’t email you a map.

Willy Wonka and the Chocolate Factory (1971)

In which a scientist uses a computer to find the “precise location of the three remaining golden tickets sent out into the world by Willy Wonka. When he asks it to spill the beans, it announces: “I won’t tell, that would be cheating.


Image: Paramount Pictures. 

The film inhabits a world where artificial intelligence has been achieved, but no one has thought to pull Charlie's poor grandparents out of extreme poverty, or design a computer with more than three buttons.

Independence Day (1996)

When an alien invasion threatens Earth, David Levinson (Jeff Goldblum) manages to stop it by hacking the alien spaceship and installing a virus. Using his Mac. Amazing, really, that aliens from across the universe would somehow use computing systems so similar to our own. 

Skyfall (2012)

In the Daniel Craig reboot of the series, MI6’s “Q” character (played by Ben Whishaw) becomes a computer expert, rather than just a gadget wizard. Unfortunately, this heralded some truly cringeworthy moments of “hacking” and “coding” in both Skyfall and Spectre (2014).

In the former, Bond and Q puzzle over a screen filled with a large, complex, web shape. They eventually realise it’s a map of subterranean London, but then the words security breach flash up, along with a skull. File under “films which make up their own operating systems because a command prompt box on a Windows desktop looks too boring”.

An honourable mention: Nelly and Kelly Rowland’s “Dilemma” (2009)

Not a movie, but how could we leave out a music video in which Kelly Rowland texts Nelly on a Microsoft Excel spreadsheet on a weird Nokia palm pilot?


Image: Vevo.

You’ll be waiting a long time for that response, Kelly. Try Tinder instead.

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.