Our pick of the week’s science and tech stories, including the recruitment drive for hackers and the problem with going back in time to assassinate leaders.

Why you can’t travel back in time and kill Hitler
Lauren Davis | i09 | 7 September 2013

All kinds of reasons, according to writers who have gamed this one through. For example, you may find you are part of a predestination paradox: “Katherine Heigl travels to 1889 Austria in order to kill the infant Hitler. She succeeds in killing the baby by jumping into a river with it, but Adolph’s mother buys another baby and raises it as her own. And that baby grows into the Adolph Hitler that Heigl’s character set out to kill.”

Geeks on the front lines
David Kushner | Rolling Stone | 11 September 2013

US government and corporate recruiters vie to hire hackers, as cyberwarfare escalates. If you know how to break into the Chinese government’s computers, chances are the US government would like to use your services – and vice-versa. Security contractors are booming, and boasting. “If [the U.S. government] came to a company like us and said, ‘Here’s $15 million,’ we could turn a North Korean missile into a brick.”

How we invented old people
Laura Helmuth | Slate | 9 September 2013

Basic structure of populations has changed twice in human history: around 30,000 years ago when people started living beyond the age of 30, and in the 19C when the average lifespan doubled in much of the world. Longevity and human development form a virtuous circle. Older people accumulate skills, wisdom, knowledge, and pass them on to younger people. Thirty is a crucial threshold because it allows for living grandparents.

Adam Gopnik | New Yorker | 9 September 2013

On the reaction against neuroscience as the answer to everything. “Neuroscience can often answer the obvious questions but rarely the interesting ones. It can tell us how our minds are made to hear music, but not why Mozart is more profound than Manilow. Asserting that an emotion is really real because you can somehow see it happening in the brain adds nothing to our understanding.”

Did the NSA secretly make a major math breakthrough?
Joe Kloc | Daily Dot | 7 September 2013

If the NSA really has worked out how to break the encryption used for banking transactions, that would be “a serious mathematical accomplishment, far beyond being just Internet security”. But since the Department of Defence spends $11bn a year on cryptanalysis, it may just have risen to the occasion. Sensibility alert: The explanation given here involves a certain amount of algebra, and lots of prime numbers           (1,400 words)

Stay secure against NSA Surveillance
Bruce Schneier | Guardian | 5 September 2013
Use strong open-source cryptography. If you use a commercial product, the NSA probably has a back-door into it. Keep private stuff on a computer with no internet connection, and if you want to send it somewhere, walk it over to a connected computer on a USB stick. Do use Tor: “Yes, the NSA targets Tor users, but it’s work for them. The less obvious you are, the safer you are. Our best defense is to make surveillance of us as expensive as possible.”

Jellyfish and world domination
Tim Flannery | New York Review Of Books | 5 September 2013

In form, a review of Stung! On Jellyfish Blooms and the Future of the Ocean, by Lisa-ann Gershwin. In substance, a compendium of amazing and mostly horrifying facts about jellyfish, which are, apparently, taking over the world, or at least the marine portion of it. They can halt battleships, overturn trawlers, shut down power stations, wipe out fisheries, blockade continents. The Black Sea has become “effectively jellified.”

The social life of genes
David Dobbs | Pacific Standard | 3rd September 2013

After the rise of genetics and evidence that our essence is inherited, the case for environmental factors makes a comeback. It is not just the genes you’ve got that make you who you are; it’s also how your individual genes behave and interact, which changes with environment. Move a European bee into an African colony and you see a cascade of changes in the bee’s genetic activity. The bee becomes a different bee. People likewise.

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