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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7 problems with the Snooper’s Charter, according to the experts

In short: it was written by people who "do not know how the internet works".

A group of representatives from the UK Internet Service Provider’s Association (ISPA) headed to the Home Office on Tuesday to point out a long list of problems they had with the proposed Investigatory Powers Bill (that’s Snooper’s Charter to you and me). Below are simplified summaries of their main points, taken from the written evidence submitted by Adrian Kennard, of Andrews and Arnold, a small ISP, to the department after the meeting. 

The crucial thing to note is that these people know what they're talking about - the run the providers which would need to completely change their practices to comply with the bill if it passed into law. And their objections aren't based on cost or fiddliness - they're about how unworkable many of the bill's stipulations actually are. 

1. The types of records the government wants collected aren’t that useful

The IP Bill places a lot of emphasis on “Internet Connection Records”; i.e. a list of domains you’ve visited, but not the specific pages visited or messages sent.

But in an age of apps and social media, where we view vast amounts of information through single domains like Twitter or Facebook, this information might not even help investigators much, as connections can last for days, or even months. Kennard gives the example of a missing girl, used as a hypothetical case by the security services to argue for greater powers:

 "If the mobile provider was even able to tell that she had used twitter at all (which is not as easy as it sounds), it would show that the phone had been connected to twitter 24 hours a day, and probably Facebook as well… this emotive example is seriously flawed”

And these connection records are only going to get less relevant over time - an increasing number of websites including Facebook and Google encrypt their website under "https", which would make finding the name of the website visited far more difficult.

2. …but they’re still a massive invasion of privacy

Even though these records may be useless when someone needs to be found or monitored, the retention of Internet Connection Records (ICRs) is still very invasive – and can actually yield more information than call records, which Theresa May has repeatedly claimed are their non-digital equivalent.

Kennard notes: “[These records] can be used to profile [individuals] and identify preferences, political views, sexual orientation, spending habits and much more. It is useful to criminals as it would easily confirm the bank used, and the time people leave the house, and so on”. 

This information might not help find a missing girl, but could build a profile of her which could be used by criminals, or for over-invasive state surveillance. 

3. "Internet Connection Records" aren’t actually a thing

The concept of a list of domain names visited by a user referred to in the bill is actually a new term, derived from the “Call Data Records" collected by hone companies. Compiling them is possible, but won't be an easy or automatic process.

Again, this strongly implies that those writing the bill are using their knowledge of telecommunications surveillance, not internet era-appropriate information. Kennard calls for the term to be removed form the bill. or at least its “vague and nondescript nature” made clear.

4. The surveillance won’t be consistent and could be easy to dodge

In its meeting with the ISPA, the Home Office implied that smaller Internet service providers won't be forced to collect these ICR records, as it's a costly process. But this means those seeking to avoid surveillance could simply move over to a smaller provider. Bit of a loophole there. 

5. Conservative spin is dictating the way we view the bill 

May and the Home Office are keen for us to see the surveillance in the bill as passive: internet service providers must simply log the domains we visit, which will be looked at in the event that we are the subject of an investigation. But as Kennard notes, “I am quite sure the same argument would not work if, for example, the law required a camera in every room in your house”. This is a vast new power the government is asking for – we shouldn’t allow politicians to play it down.

6. The bill would allow our devices to be bugged

Or, in the jargon, used in the draft bill, subjected to “equipment interference”. This could include surveillance of all use of a phone or laptop, or even the ability to turn on its camera or webcam to watch someone. The bill actually calls for “bulk equipment interference” – when surely, as Kennard notes, “this power…should only be targeted at the most serious of criminal suspects" at most.

7. The ability to bug devices would make them less secure

Devices can only be subject to “equipment interference”, or bugging, if they have existing vulnerabilities, which could also be exploited by criminals and hackers. If security services know about these vulnerabilities, they should tell the manufacturer about them. As Kennard writes, allowing equipment interference "encourages the intelligence services to keep vulnerabilities secret” so they don't lose their own access to our devices. Meanwhile, though, they're laying the population open to hacks from cyber criminals. 


So there you have it  – a compelling soup of misused and made up terms, and ethically concerning new powers. 

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