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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From Darwin to Damore - the ancient art of using "science" to mask prejudice

Charles Darwin, working at a time when women had little legal rights, declared “woman is a kind of adult child”.

“In addition to the Left’s affinity for those it sees as weak, humans are generally biased towards protecting females,” wrote James Damore, in his now infamous anti-diversity Google memo. “As mentioned before, this likely evolved because males are biologically disposable and because women are generally more co-operative and agreeable than men.” Since the memo was published, hordes of women have come forward to say that views like these – where individuals justify bias on the basis of science – are not uncommon in their traditionally male-dominated fields. Damore’s controversial screed set off discussions about the age old debate: do biological differences justify discrimination?  

Modern science developed in a society which assumed that man was superior over women. Charles Darwin, the father of modern evolutionary biology, who died before women got the right to vote, argued that young children of both genders resembled adult women more than they did adult men; as a result, “woman is a kind of adult child”.

Racial inequality wasn’t immune from this kind of theorising either. As fields such as psychology and genetics developed a greater understanding about the fundamental building blocks of humanity, many prominent researchers such as Francis Galton, Darwin’s cousin, argued that there were biological differences between races which explained the ability of the European race to prosper and gather wealth, while other races fell far behind. The same kind of reasoning fuelled the Nazi eugenics and continues to fuel the alt-right in their many guises today.

Once scorned as blasphemy, today "science" is approached by many non-practitioners with a cult-like reverence. Attributing the differences between races and gender to scientific research carries the allure of empiricism. Opponents of "diversity" would have you believe that scientific research validates racism and sexism, even though one's bleeding heart might wish otherwise. 

The problem is that current scientific research just doesn’t agree. Some branches of science, such as physics, are concerned with irrefutable laws of nature. But the reality, as evidenced by the growing convergence of social sciences like sociology, and life sciences, such as biology, is that science as a whole will, and should change. The research coming out of fields like genetics and psychology paint an increasingly complex picture of humanity. Saying (and proving) that gravity exists isn't factually equivalent to saying, and trying to prove, that women are somehow less capable at their jobs because of presumed inherent traits like submissiveness. 

When it comes to matters of race, the argument against racial realism, as it’s often referred to, is unequivocal. A study in 2002, authored by Neil Risch and others, built on the work of the Human Genome Project to examine the long standing and popular myth of seven distinct races. Researchers found that  “62 per cent of Ethiopians belong to the same cluster as Norwegians, together with 21 per cent of the Afro-Caribbeans, and the ethnic label ‘Asian’ inaccurately describes Chinese and Papuans who were placed almost entirely in separate clusters.” All that means is that white supremacists are wrong, and always have been.

Even the researcher Damore cites in his memo, Bradley Schmitt of Bradley University in Illinois, doesn’t agree with Damore’s conclusions.  Schmitt pointed out, in correspondence with Wired, that biological difference only accounts for about 10 per cent of the variance between men and women in what Damore characterises as female traits, such as neuroticism. In addition, nebulous traits such as being “people-oriented” are difficult to define and have led to wildly contradictory research from people who are experts in the fields. Suggesting that women are bad engineers because they’re neurotic is not only mildly ridiculous, but even unsubstantiated by Damore’s own research.  As many have done before him, Damore couched his own worldview - and what he was trying to convince others of - in the language of rationalism, but ultimately didn't pay attention to the facts.

And, even if you did buy into Damore's memo, a true scientist would retort - so what? It's a fallacy to argue that just because a certain state of affairs prevails, that that is the way that it ought to be. If that was the case, why does humanity march on in the direction of technological and industrial progress?

Humans weren’t meant to travel large distances, or we would possess the ability to do so intrinsically. Boats, cars, airplanes, trains, according to the Damore mindset, would be a perversion of nature. As a species, we consider overcoming biology to be a sign of success. 

Of course, the damage done by these kinds of views is not only that they’re hard to counteract, but that they have real consequences. Throughout history, appeals to the supposed rationalism of scientific research have justified moral atrocities such as ethnic sterilisation, apartheid, the creation of the slave trade, and state-sanctioned genocide.

If those in positions of power genuinely think that black and Hispanic communities are genetically predisposed to crime and murder, they’re very unlikely to invest in education, housing and community centres for those groups. Cycles of poverty then continue, and the myth, dressed up in pseudo-science, is entrenched. 

Damore and those like him will certainly maintain that the evidence for gender differences are on their side. Since he was fired from Google, Damore has become somewhat of an icon to some parts of society, giving interviews to right-wing Youtubers and posing in a dubious shirt parodying the Google logo (it now says Goolag). Never mind that Damore’s beloved science has already proved them wrong.