Olivaceous Warbler and Quantum Confusion

On Saturday a  rare Eastern Olivaceous Warbler was found at Farlington marshes in Hampshire. I believe this is only the 22^nd UK record of this warbler more usually found in a Greek olive grove or an Algerian oasis. It would also represent a life tick for me. Family and other commitments dictated that the first day I could sensibly twitch this mega was today. I decided to wait until the bird was reported on RBA before setting off on the 90-minute journey from home. Somewhat worryingly, the bird was not reported until almost 10 am and was noted as being “seen only briefly”. I’ve been caught out by such reports before as some of them have have turned out to be erroneous but  I decided to be optimistic and set off anyway

On arrival there were 30 or so birders present and I was told that the bird had been seen briefly some 15 minutes prior to my arrival. I also discovered that some birders present had spent 5 hours not seeing the bird the previous day. It turned out that it was very much my lucky day as, shortly after my arrival, the warbler showed relatively well for 90 minuets.  The bright warm sun certainly was an advantage as there were many active insects available for it to feed on.

Now … I think its time for another major digression …………

So, again, if you are only interested in the birding aspect of my blog, stop reading now!

I never did have a good response when asked at student parties “what do you do” The factual answer, “I’m researching quantum fluids “, will certainly not be found in any book of chat up lines!

In my opinion, the problem in explain quantum mechanics to the non-physicist is twofold. 

Firstly, the language of physics is mathematics and if you don’t speak the language its by definition very hard to explain. An analogue would be trying to explain what a flower smells like over the phone to someone who only spoke French when you did not.

Secondly, in order to understanding quantum mechanics you have to accept that the physical environment we live in in terms of temperature, pressure, length scales etc., is only a very small sub set of all the possible environments the universe has to offer. You have to then also accept that our perception of reality, while being absolute in our little sub-space of environments, may not be true for the vast spectrum of environments that the universe has to offer.

Quantum mechanics deals mainly with the very small, i.e. atoms and elementary particles. It says that certain properties that are absolute in our little world, position, velocity etc. are not absolute in the world of atoms. Rather outcomes can only be described by a  probability. 

What does this somewhat obscure statement actually mean? In the world we are used to if you hit a snooker ball in exactly the same way many times with the cue ball it will always move off in exactly the same direction. In physics speak the outcome is totally deterministic.  In the quantum world this is not so!! There are a range of possible directions the ball can move off in and you can only assign a probability to the likely direction, i.e. it is not fully deterministic. While this seems very strange to us humans, it has been proven time and time again over the past 100 years by experiment. In fact many of the devices we take for granted in modern life, computers, mobile phones etc. can only be described at a fundamental level if this is true.

Lets take a different example of something that most people will have some familiarly with, radioactivity. A lump of radioactive material is composed of billions and billions of identical unstable atoms.  The half-life of this material is when half of them have decayed. So why, if they are identical, do they not all decay at once? Its down to good old quantum mechanics which says that the seemly identical atoms will not decay at the same time, rather you can only assign a probability to a certain atom decaying at a certain time. The half-life is when the probability that all the atoms have decayed is half!

Having probably completely failed to explain this, I plan to move on to something even harder to explain next time, quantum entanglement. This strange phenomena that defies common sense is at the heart of the emergent quantum information technology revolution which, I’m pretty, sure, is destined to change our lives every bit as much as the invention of the computer, mobile phone or TV did.

I feel I should end on a lighter but related note on how (not) to explain quantum mechanics. When I was MD at Oxford Instruments we were lucky enough to win the Queens award for technology for a device which cooled the quantum processor in a quantum computer to very low temperatures, a necessary requirement for it to function. We were invited to a reception with the Queen at Buckingham palace to celebrate our award. I took the very talented physicist who was in change of the development with me. Knowing that the Queen would ask us what we had won the award for I told him that on no account was he to try and explain to the Queen what a quantum computer was!! At the reception the Queen duly asked me what we had won the award for. I said that we had invented technology to help make the next generation of superfast computers. She then asked my colleague what he did – his reply was priceless – “the same as him”!