Hang on a second: clocks at a Hong Kong clock and watch fair. Photo: Getty
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The pros and cons of leap seconds

The slowing pace of the earth’s spin means that occasionally we have to add on a second – but should this practice continue?

The British science minister, David Willetts, wants your input on an issue you’ve probably never even thought about. The question, in essence, is this: would you care if, in 800 years’ time, the sun was at its highest point overhead at 1pm, rather than today’s 12 noon?

There’s an international scientific kerfuffle over this. It is prompted by the changing pace of the earth’s spin. The moon and sun pull on our planet, slowing its rotation and giving us an ever-lengthening day. The effect is tiny – adding less than two-thousandths of a second per day – and it is not consistent. Sometimes, the rotation even speeds up for a while. We’re not sure why but we think it is because interactions between earth’s liquid iron core and the rocky mantle that surrounds it can exert an accelerating effect. Ocean currents also seem to speed up the pace at which the

world turns. In the long term, though, we know the days are getting longer. As a result, occasionally, to keep our clocks in sync with when we expect sunrise and sunset to occur, we have to add a “leap second”.

It sounds easy but it’s not. For 14 years, countries have been debating whether the practice of adding a leap second should continue. Shoehorning an extra second into the clocks of computer programs can create software glitches that have widespread effects. In 1998, for instance, the insertion of a leap second caused a mobile-phone blackout across the southern United States because different regions were suddenly operating with time differences outside the error tolerances. Then in 2012 an airline’s booking system went belly-up for hours after a leap second insertion. The US department of defence has argued vociferously that the leap second compromises the “safety and reliability” of certain systems; scaremongers talk about missiles and air-traffic control systems going awry in some such future adjustment.

One solution to this is to let our clock readings gradually drift away from any association with the position of the sun in the sky. After all, who cares?

Well, you – perhaps. Britain is one of very few nations that have battled to keep the leap second. Most countries are happy to let the clocks drift away from “solar time”. The reason for Britain’s reticence is largely to do with ministerial gut feeling about our sense of cultural heritage: the time of day has always been linked with the position of the sun in the sky and why should we abandon that just because some programmers can’t do their job properly? In April, the UK government launched a public consultation to find out what you think (full disclosure: I am on the consultation’s oversight committee checking that the process is fair and frank).

There are potential issues with abandoning the leap second. Human beings have always lived by sunrise and sunset; our biology responds to rising and fading light levels. Without leap seconds, or some other adjustment of time, noon in the year 4000 will occur in total darkness. Also, the sun’s position in the sky plays a role in the timing of certain religious observances. Whether the link to the numbers on a clock face matters in these instances is as yet unknown, hence the consultation. Can we justify dropping the leap second – and maybe redefining “noon” – just because of computer programming problems?

On the other hand, some will argue that we cope with time zones and daylight saving time; why would we care about a second every few years? That’s for you to answer, if you care enough to bother.

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 01 May 2014 issue of the New Statesman, The Islam issue

DebateTech
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Politicians: it's no longer OK to know nothing about technology

It’s bad enough to joke about not being "techy"; it's worse to back a piece of legislation from a position of ignorance. 

Earlier this week, facing down a 600-strong battalion of London’s tech sector at a mayoral hustings in Stratford, Zac Goldsmith opened his five minute pitch with his characteristic charm. “I’m not very techy!” he exclaimed. “I understand coding about as well as Swahili!”

Pointless jibe at a foreign language aside, this was an ill-chosen way to begin his address - especially considering that the rest of his speech showed he was reasonably well-briefed on the problems facing the sector, and the solutions (including improving broadband speeds and devolving skills budgets) which could help.

But the offhand reference to his own ignorance, and the implication that it would be seen as attractive by this particular audience, implies that Goldsmith, and other politicians like him, haven’t moved on since the 90s. The comment seemed designed to say: “Oh, I don't know about that - I'll leave it to the geeks like you!"

This is bad enough from a mayoral hopeful.  But on the same day, the Intelligence and Security Committee of Parliament filed its report on the Draft Investigatory Powers Bill, the legislation drafted by the Home Office which will define how and how far the government and secret services can pry into our digital communications. Throughout, there's the sense that the ISC doesn't think the department behind the bill had a firm grasp on the issues at hand. Words like "inconsistent" and "lacking in clarity" pop up again and again. In one section, the authors note:

"While the issues under consideration are undoubtedly complex, we are nevertheless concerned that thus far the Government has missed the opportunity to provide the clarity and assurance which is badly needed."

The report joins criticism from other directions, including those raised by Internet Service Providers last year, that the bill's writers didn't appear to know much about digital communications at all, much less the issues surrounding encryption of personal messages.

One good example: the bill calls for the collection of "internet connection records", the digital equivalent of phone call records, which show the domains visited by internet users but not their content. But it turns out these records don't exist in this form: the bill actually invented both the phrase and the concept. As one provider commented at the time, anyone in favour of their collection "do not understand how the Internet works". 

Politicians have a long and colourful history of taking on topics - even ministerial posts - in fields they know little to nothing about. This, in itself, is a problem. But politicians themselves are often the people extolling importance of technology, especially to the British economy - which makes their own lack of knowledge particularly grating. No politician would feel comfortable admitting a lack of knowledge, on, say, economics. I can’t imagine Goldsmith guffawing "Oh, the deficit?  That's all Greek to me!"  over dinner with Cameron. 

The mayoral candidates on stage at the DebateTech hustings this week were eager to agree that tech is London’s fastest growing industry, but could do little more than bleat the words “tech hub” with fear in their eyes that someone might ask them what exactly that meant. (A notable exception was Green candidate Sian Berry, who has actually worked for a tech start-up.) It was telling that all were particularly keen on improving internet speeds -  probably because this is something they do have day-to-day engagement with. Just don't ask them how to go about doing it.

The existence of organisations like Tech London Advocates, the industry group which co-organised the hustings, is important, and can go some way towards educating the future mayor on the issues the industry faces. But the technology and information sectors have been responsible for 30 per cent of job growth in the capital since 2009 - we can't afford to have a mayor who blanches at the mention of code. 

If we’re to believe the politicians themselves, with all their talk of coding camps and skills incubators and teaching the elderly to email, we need a political sphere where boasting that you're not "techy" isn’t cool or funny - it’s just kind of embarrassing. 

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