Mark Carney: time lord?

Is the bank of England Governor messing with the very fabric of time?

Time isn’t a very interesting idea to a physicist. There is the unchangeable past and the unpredictable future. “Now” isn’t a definable concept. It’s not even fixed – you can bend it. Time is a sort of illusionary bi-product spit out as the universe goes from a state of order to one of chaos. Why politicians and central bankers would want to start messing with it is a mystery.

Mark Carney, the Governor of the Bank of England, and the Monetary Policy Committee have been lured into the time game. They expect one of their trigger points, unemployment, to drop below 7 percent in 2016 at which point they’ll have a look at what they might - or might not do. In the world of the Bank of England this constitutes "delivering a measure of certainty". The previous governor, Sir Mervyn King, just used to say "I don’t know" when faced with demands for definiteness.

With unemployment currently at 7.8 per cent three years seems a long and unambitious timescale to set yourself such a meager target. Carney says that to achieve the 7 per cent unemployment rate a million jobs will have to be created – 750,000 new ones and 250,000 to compensate for planned reductions in public jobs and that is what will take the time.  Markets disagree and have pumped up their rate increase expectation to as early as next summer. Somebody is wrong.

Perversely, if you were Chancellor of the Exchequer, George Osborne, or a Conservative Party election campaign organizer, you might be pretty happy with the idea that unemployment wasn’t going to fall any time soon. The reason is simple – over the years the multiple of house prices to earnings has risen for about 3.5 to 6.5 for England as a whole (your main electoral battle ground) and the electorate has become twice as sensitive to interest rate movements today as they were twenty years ago (see graph). Get interest rate policy wrong and it could have electoral consequences.

By mapping where house prices are highest relative to earnings it’s easy to show that above average interest rate sensitivity lies almost exclusively in Conservative-held boundaries; the East, South East and South West (see second graph).  London is the exception but suffers the double whammy of being both the most leveraged part of the country AND dominated by Labour. You’ll get no votes from Londoners for increasing interest rates too soon.

Also the higher house price-to-earnings regions are associated with areas with higher salaries which already carry the highest level of taxation. Those earning up to £50,000 a year now have total deductions (National Insurance and Income Tax) of about 20 per cent whilst if you earn between £50,000 – 100,000 this rises to 32 per cent. In the £100,000 to 200,000 bracket your annual deductions bill averages 40 per cent of gross salary. By linking housing costs (i.e. an interest only mortgage) to where you are on the income scales it can be shown that for every 0.5 per cent interest rate increase could lead an equivalent of between 2 per cent and 4 per cent increase income tax. Increasing interest rates in that sense hits traditional Conservative voters harder than potential converts from the Liberal Democrats of even Labour.

None of this should come as a surprise to people but the extent of the apparent hyper-sensitivity of the electorate to interest movements is going to be more economically and politically important at the next general election than it has ever been before. The MPC will have to be doubly sure they have a self-sustaining economic cycle, embedded in a stable global background, before increasing interest rates. It may even be why they have set their earliest revue date to beyond the next general election. In that sense Mark Carney has been right to dampen the enthusiasm the markets have shown for marginally stronger UK data recently whilst if you were Conservative Party Chairman you would be praying that not too many jobs are created too quickly especially before the General Election in 2015.  

 

        

Source: HM Land Registry

                                 

Mark Carney. Photograph: Getty Images

Head of Fixed Income and Macro, Old Mutual Global Investors

Getty
Show Hide image

Inside Big Ben: why the world’s most famous clock will soon lose its bong

Every now and then, even the most famous of clocks need a bit of care.

London is soon going to lose one of its most familiar sounds when the world-famous Big Ben falls silent for repairs. The “bonging” chimes that have marked the passing of time for Londoners since 1859 will fall silent for months beginning in 2017 as part of a three-year £29m conservation project.

Of course, “Big Ben” is the nickname of the Great Bell and the bell itself is not in bad shape – even though it does have a huge crack in it.

The bell weighs nearly 14 tonnes and it cracked in 1859 when it was first bonged with a hammer that was way too heavy.

The crack was never repaired. Instead the bell was rotated one eighth of a turn and a lighter (200kg) hammer was installed. The cracked bell has a characteristic sound which we have all grown to love.

Big Ben strikes. UK Parliament.

Instead, it is the Elizabeth Tower (1859) and the clock mechanism (1854), designed by Denison and Airy, that need attention.

Any building or machine needs regular maintenance – we paint our doors and windows when they need it and we repair or replace our cars quite routinely. It is convenient to choose a day when we’re out of the house to paint the doors, or when we don’t need the car to repair the brakes. But a clock just doesn’t stop – especially not a clock as iconic as the Great Clock at the Palace of Westminster.

Repairs to the tower are long overdue. There is corrosion damage to the cast iron roof and to the belfry structure which keeps the bells in place. There is water damage to the masonry and condensation problems will be addressed, too. There are plumbing and electrical works to be done for a lift to be installed in one of the ventilation shafts, toilet facilities and the fitting of low-energy lighting.

Marvel of engineering

The clock mechanism itself is remarkable. In its 162-year history it has only had one major breakdown. In 1976 the speed regulator for the chimes broke and the mechanism sped up to destruction. The resulting damage took months to repair.

The weights that drive the clock are, like the bells and hammers, unimaginably huge. The “drive train” that keeps the pendulum swinging and that turns the hands is driven by a weight of about 100kg. Two other weights that ring the bells are each over a tonne. If any of these weights falls out of control (as in the 1976 incident), they could do a lot of damage.

The pendulum suspension spring is especially critical because it holds up the huge pendulum bob which weighs 321kg. The swinging pendulum releases the “escapement” every two seconds which then turns the hands on the clock’s four faces. If you look very closely, you will see that the minute hand doesn’t move smoothly but it sits still most of the time, only moving on each tick by 1.5cm.

The pendulum swings back and forth 21,600 times a day. That’s nearly 8m times a year, bending the pendulum spring. Like any metal, it has the potential to suffer from fatigue. The pendulum needs to be lifted out of the clock so that the spring can be closely inspected.

The clock derives its remarkable accuracy in part from the temperature compensation which is built into the construction of the pendulum. This was yet another of John Harrison’s genius ideas (you probably know him from longitude fame). He came up with the solution of using metals of differing temperature expansion coefficient so that the pendulum doesn’t change in length as the temperature changes with the seasons.

In the Westminster clock, the pendulum shaft is made of concentric tubes of steel and zinc. A similar construction is described for the clock in Trinity College Cambridge and near perfect temperature compensation can be achieved. But zinc is a ductile metal and the tube deforms with time under the heavy load of the 321kg pendulum bob. This “creeping” will cause the temperature compensation to jam up and become less effective.

So stopping the clock will also be a good opportunity to dismantle the pendulum completely and to check that the zinc tube is sliding freely. This in itself is a few days' work.

What makes it tick

But the truly clever bit of this clock is the escapement. All clocks have one - it’s what makes the clock tick, quite literally. Denison developed his new gravity escapement especially for the Westminster clock. It decouples the driving force of the falling weight from the periodic force that maintains the motion of the pendulum. To this day, the best tower clocks in England use the gravity escapement leading to remarkable accuracy – better even than that of your quartz crystal wrist watch.

In Denison’s gravity escapement, the “tick” is the impact of the “legs” of the escapement colliding with hardened steel seats. Each collision causes microscopic damage which, accumulated over millions of collisions per year, causes wear and tear affecting the accuracy of the clock. It is impossible to inspect the escapement without stopping the clock. Part of the maintenance proposed during this stoppage is a thorough overhaul of the escapement and the other workings of the clock.

The Westminster clock is a remarkable icon for London and for England. For more than 150 years it has reminded us of each hour, tirelessly. That’s what I love about clocks – they seem to carry on without a fuss. But every now and then even the most famous of clocks need a bit of care. After this period of pampering, “Big Ben” ought to be set for another 100 or so years of trouble-free running.

The Conversation

Hugh Hunt is a Reader in Engineering Dynamics and Vibration at the University of Cambridge.

This article was originally published on The Conversation. Read the original article.