Archive for February, 2016

Star of India

February 23, 2016
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Sam Gibbs is a star of India

So having left the UK on Sunday night, I arrived in India on Monday morning. Everything went straightforwardly and I kept my anxiety in check :-).

Then, having been over-charged for a taxi ride, I made it to my hotel, closed the door and I spent most of Monday writing slides for my presentation tomorrow morning.

The talk includes our new data on the most accurate temperature measurements in human history [more of which in a later story].  So I ought to feel confident. But I am unsure of this audience, and I still feel a bit bleary, so I am not entirely happy that I have the tone and level correct. But in any case it’s done now.

However, on setting up e-mail communication I was shocked to receive an e-mail from Sam Gibbs – someone I have never met – but with whom I have had lengthy e-mail interactions about a cool water rocket system he developed in Malaysia. I did not know he had been in Delhi for the last two years.

But having read my previous blog, he e-mailed offering ‘assistance and company’. I was overwhelmed at the kindness of his offer.

So, I learned to use the Metro system (excellent and cheap: £3 for a 3 day pass)…

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…and headed ‘down town’. In the park  I saw some traditional and modern dance…

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…then met up with Sam for a curry at a very pleasant ‘cafe’ with a rooftop terrace  overlooking the ‘central’ park.

Over dinner I heard about Sam’s work bringing cool science to schools all around India, and his hope that the insights of science would somehow improve the lot of individuals and communities. And I remembered what I said in my blog before I left England.

I am travelling in the hope of meeting new friends, learning about metrology research in India  and seeing the world from further East than I have ever travelled before.

Well, I was – and am – travelling in hope, but I didn’t think I would meet anyone as kind and friendly as Sam: a true star of India.

Let’s hope the ‘metrology research’ goes just as well.

 

 

 

 

 

Anxiety Update

February 21, 2016
A picture of me taken this summer.

A picture of me taken this summer.

At the start of this year I resolved not to become gut-wrenchingly anxious.

Since then, many friends and colleagues, on- and off-line, have exchanged words of empathy and support, compassion and positivity. Thank you 🙂

And so I just thought I would note that despite being behind in everything I am doing, I have actually been doing OK on the anxiety front.

But later today I fly to India for a week and I have to admit my anxiety is rising again.

Even at the best of times I am not a relaxed traveller. And since India is renowned for a degree of chaos, I have plenty of concrete reasons to be anxious: getting a visa was chaotic and unbelievably bureaucratic; the Air India web check-in doesn’t seem to work; and apparently Delhi is on the verge of a riot-induced water crisis.

But on the other hand, I do now have a visa. I will travel early to the airport to allow time for any check-in chaos. And in all likelihood the water supply that is threatened is probably not the supply of bottled water I intend to be using.

So, I am travelling in the hope of meeting new friends, learning about metrology research in India  and seeing the world from further East than I have ever travelled before.

I’ll let you know how it goes. Now: I must finish that PowerPoint presentation…

 

Canadian Currency is the Coolest

February 8, 2016
Canadian dollars are printed on plastic. That means they are see-through ans washable!

Canadian dollars are printed on plastic. That means they are see-through and washable!

One of the most memorable features of my visit to Canada was the money: the notes are made of plastic!

At first, this seemed a bit weird. But I quickly got used to it. And then I came to like it.

Think about it.

If your notes get wet – it’s no problem!. Just towel it dry.

They are much harder to counterfeit. Printing on plastic is harder and the notes have loads of security features. They have all the foils, detailed printing and embossing that we are used to in UK bank notes. Plus one unique feature: a projection hologram.

If you shine a laser pointer through the centre of the maple leaf that features on all the bank notes, the projected image will show the value the currency!

Laser Diffraction montage

Shining a laser pointer through the maple leaf reveals the value of the bank note. In this case, 5$

Can you get cooler than that? Yes, you can. You can get the second coolest Canadian ever – Commander Chris Hadfield – he of the Space Oddity video – to announce the new $5 bank note (which features the Canadian ‘Arm’ on the space station) from space!

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So who was the coolest Canadian ever? Well surely it was, is and always will be, Leonard Cohen?

Science in the face of complexity

February 4, 2016
Jeff Dahn: Battery Expert at Dalhousie University

Jeff Dahn: Battery Expert at Dalhousie University

My mother-in-law bought me a great book for Christmas: Black Box Thinking by Matthew Syed: Thanks Kathleen 🙂

The gist of the book is easy to state: our cultural attitude towards “failure”- essentially one of blame and shame – is counter productive.

Most of the book is spent discussing this theme in relation to the practice of medicine and the law, contrasting attitudes in these areas to those in modern aviation. The stories of unnecessary deaths and of lives wasted are horrific and shocking.

Engineering

But when he moves on to engineering, the theme plays out more subtly. He discusses the cases of James Dyson, the Mercedes Formula 1 team, and David Brailsford from Sky Cycling. All of them have sought success in the face of complexity.

In the case of Dyson, his initial design of a ‘cyclone-based’ dust extractor wasn’t good enough, and the theory was too complex to guide improvements. So he started changing the design and seeing what happened. As recounted, he investigated 5,127 prototypes before he was satisfied with the results. The relevant point here is that his successful design created 5,126 failures.

One of his many insights was to devise a simple measurement technique that detected tiny changes in the effectiveness of his dust extraction: he sucked up fine white dust and blew the exhaust over black velvet.

Jeff Dahn

This approach put me in mind of Jeff Dahn, a battery expert I met at Dalhousie University.

Batteries are really complicated and improving them is hard because there are so many design features that could be changed. What one wants is a way to test as many variants as quickly and as sensitively as possible in order to identify what works and what doesn’t.

However when it comes to battery lifetime – the rate at which the capacity of a battery falls over time – it might seem inevitable that this would take years.

Not so. By charging and discharging batteries in a special manner and at elevated temperatures, it is possible to accelerate the degradation. Jeff then detects this with precision measurements of the ‘coulombic efficiency’ of the cell.

‘Coulombic efficiency’ sounds complicated but is simple. One first measures the electric current as the cell is charged. If the electric current is constant during charging then the electric current multiplied by the charging time gives the total amount of electric charge stored in the cell. One then measures the same thing as the cell discharges.

For the lithium batteries used in electric cars and smart phones, the coulombic efficiency is around 99.9%. But it is that tiny of amount (less than 0.1%) of the electric charge which doesn’t come back that is progressively damaging the cell and limiting it’s life.

One of Jeff’s innovations is the application of precision measurement to this problem. By measuring electric currents with uncertainties of around one part in a million, Jeff can measure that 0.1% of non-returned charge with an uncertainty of around 0.1%. So he can distinguish between cells that 99.95% efficient and 99.96% efficient. That may not sound much, but the second one is 20% better!

By looking in detail at the Coulombic efficiencyJeff can tell in a few weeks whether a new design of electrode will improve or degrade battery life.

The sensitivity of this test is akin to the ‘white dust on black velvet’ test used by Dyson: it doesn’t tell him why something got better or worse – he has to figure that out for himself. But it does tell him quickly which things were bad ideas.

I couldn’t count the ammeters in Jeff’s lab – each one attached to a test cell – but he was measuring hundreds of cells simultaneously. Inevitably, most of these tests will make the cells perform worse and be categorised as ‘failures’.

But this system allows him to fail fast and fail often: and it is this capability that allows him to succeed at all. I found this application of precision measurement really inspiring.

Thanks Jeff.

 

 

 

 

 

Restoring my faith in Quantum Computing

February 1, 2016
Jordan Kyriakidis from Dalhousie University Physics Department

Jordan Kyriakidis from Dalhousie University Physics Department

I am a Quantum Computing Sceptic.

But last week at Dalhousie I met Jordan Kyriakidis who explained one feature of Quantum Computing that I had not appreciated. That even if a quantum computer only gave the right answer one time in a million operations, it might still be useful.

His insight made me believe that Quantum Computing just might be possible.

[Please be aware that I am not an expert in this field. And I am aware that experts are less sceptical than I am. Indeed many consider that the power of quantum computing has already been demonstrated. Additionally Scott Arronson  argues persuasively (in his point 7) that my insight is wrong.]

Background

Conventional digital computers solve problems using mathematics. They have been engineered to perform electronic operations on representations of numbers which closely mimic equivalent mathematical operations.

Quantum computers are different. They work by creating a physical analogue of the problem which requires solving.

An initial state is created and then the computational ‘engine’ is allowed to evolve using basic physical laws and hopefully arrive at a state which represents a solution to the problem at hand.

My problem

There are many conceivable implementations of a quantum computer and I am sceptical about them all!

My scepticism arises from the analogue nature of the computation. At some point the essential elements of the quantum computer (called ‘Qubits‘ and pronounced Q-bits) can be considered as some kind of oscillator.

The output of the computer – the answer – depends on interference between the Qubits being orchestrated in a precise manner. And this interference between the Qubits is completely analogue.

Analogue versus digital

Physics is fundamentally analogue. So, for example, the voltages present throughout a digital computer vary between 0 volts and 5 volts. However the engineering genius of digital electronics is that it produces voltages that are either relatively close to 0 volts, or relatively close to 5 volts. This allows the voltages to be interpreted unambiguously as representing either a binary ‘1’ or ‘0’. This is why digital computers produce exactly the same output every time they run.

Quantum Computing has outputs that can be interpreted unambiguously as representing either a binary ‘1’ or ‘0’. However the operation of the machine is intrinsically analogue. So tiny perturbations that accumulate between the thousands of operations on the Qubits in a useful machine will result in different outputs each time the machine is run.

Jordan’s Insight

To my surprise Jordan acknowledged my analysis was kind-of-not-wrong. But he said it didn’t matter for the kinds of problems quantum computers might be good at solving. The classic problem is factoring of large numbers.

For example working out that the number 1379 is the result of multiplying 7 × 197 will take you a little work. But if I gave you the numbers 7 and 197 and asked you to multiply them, you could do that straightforwardly.

Finding the factors of large numbers (100 digits or more) is hard and slow – potentially taking the most powerful computers on Earth hundreds of years to determine. But multiplying two numbers – even very large numbers – together is easy and quick on even a small computer.

So even if a quantum computer attempting to find factors of a large number were only right one time in a million operations – that would be really useful! Since the answers are are easy to check, we can sort through them and get rid of the wrong answers easily.

So a quantum computer could reduce the time to factor large numbers even though it was wrong 99.9999% of the time!

I can easily imagine quantum computers being mostly wrong and I had thought that would be fatal. But Jordan made me realise that might still be very useful.

Thanks Jordan 🙂

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By the way, you might like to check out this web site which will factor large numbers for you. I learned that the number derived from birth date (29/12/1959>>>29121959) is prime!


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