Just before Christmas I heard that I had been successful in bidding for a stand at the prestigious Royal Society Summer Science Exhibition. Competition is stiff with 75% of the proposals being rejected so somebody must think what I am doing is interesting! Wow!
Of course its not just me doing this and its not just about my work. It’s really about NPL and the importance of measurement to the country. And the reason we won a place is largely down to the enthusiasm of my colleague Andrew Hanson.
Today – along with Andrew and the other winners – I visited the Royal Society in London to be briefed on what we need to do. Having visited last year’s exhibition both as a visitor and as a helper at an NPL exhibit on bubbles, I knew that the task ahead would be exhausting. After being briefed on the design of the stand; online video and blogging; press interactions; school visits and official ‘soirees’, I left buzzing with ideas and anxiety.
We are actually combining stands with Terry Quinn and Richard Davies from the BIPM, who will bring along a ‘Do it yourself’ replacement for the kilogram. Terry and his grandson have made a model with wood, lego and a loudspeaker which is accurate to about 10%, but which demonstrates the principles of a much more complex, expensive and accurate device.
The device operates unlike almost every mass measurement made at present. Currently a mass measurement is – ultimately – a determination of the ratio of the unknown mass to the mass of the International Prototype Kilogram – the IPK. Terry’s device – called a ‘Watt Balance’ – measures mass without any reference to the IPK! Despite being very cheap – the mass measurement is made by comparing the force of gravity with an electro-magnetic force. It is – ultimately – a comparison of a mass against electrical standards which we can determine in terms of constants of nature.
Similarly my exhibit is about a thermometer that measures the speed of sound in a gas, which allows us to work out the average speed of molecules. So we can measure temperature directly in terms of the kinetic energy of molecules. This is unlike any temperature measurement made at the moment. Currently a temperature measurement tells you how much hotter or colder a thing is than the temperature of the triple point of water.
So the theme of the stand will be about measurements in everyday life being traceable to constants of nature rather than human artefacts. I love this idea – the transcendental and profound embedded into the mundane tasks of life. But what should we call the stand? Here are some ideas we are kicking around. Please vote – or suggest a new idea! Anyway, I look forward to seeing you between the 2nd and the 7th July – it’s free!