If I was asked to name my favorite UK bird I think it would be the Wryneck. This small member of the woodpecker family has the most subtle, beautiful and alluring plumage and is a really captivating bird when viewed at close range.
They are sadly long lost as UK breeding birds and can only is seen on passage, mainly in the autumn. A small influx over the past few days had me scanning the bird alert services for a suitable candidate to visit. I chose Farlington marshes in Hampshire because it was only 90 minutes from home and I’d never been there before. In addition there were a couple of half decent pictures posted indicating that reasonably views should be possible with patience.
I must say that I approached this trip with a certain amount of trepidation as I had had wonderful and unbeatable views of a Wryneck in Norfolk last year. While I was sitting on the ground it appeared from the undergrowth some 20 or so meters from me and proceeded to spend the next hour scoffing ants from an ants nest.
After a certain amount of confusion, the given shat nav address was over the other side of the busy A27 in a supermarket car park, I arrived and made the short walk to the visitors center where reports indicated it was located. It had been seen by a couple of lucky observes some 30 minutes before I arrived. I then had to wait some 5 hours for it to reappear! The views were never going to repeat last years but nonetheless the shear beauty of this natural wonder captivated me for some 15 minutes as it fed on ants before jumping up into the adjacent bramble bush and flying off. Cue time for a walk around the reserve. I believe it was not seen again for another 4 hours and then only briefly.
The reserve is a natural marshland bounded on one side by a long sea wall and on the other by the very nosily A27. There were a number of Whinchats perching on the fencing and doing their usual thing of dropping down to grab an insect and then returning to their station. There were also a number of Wheatears out on the grassland. The other highlight was a distance but beautiful Osprey which was roosting and occasionally shaking its wings on a dead tree out on an island from the sea wall.
Whinchat |
Kestrel |
Ok – if you only want to read about my birding trips stop here because I about to seriously digress!
One of the most common misconceptions that I come across as a physicist is that Einstein said that nothing can travel faster than the speed of light – WRONG!
It’s very easy to construct a simple experiment that shows why. Imagine I have a pair of scissors with a strong light source behind them. I set up a screen just far enough away from the scissors so that the shadow from the light source is exactly ten times bigger than the scissors. Now suppose I have someway of opening the scissors at 50% of the speed of light. How fast does the shadow move across the screen. Well, as is ten times larger than the actual scissors it must be five times the speed of light!
So what’s wrong with this?
Einstein famously imaged what the world would look like if he sat of a beam of light . One of the central ideas of relativity involves the flow of information via cause and effect or, because physicist like to give complicated names to simple things , causality. Einstein actually said that no (causal) information can be transferred at greater than the speed of light in vacuum. So now imagine you are an observer on the screen at the point of the scissors when closed and you use a telescope to look at when the shadow reaches the point when the scissors are open. How quickly has this information been transferred to the observer. Well it’s at the speed of light because he is using light to convey the information with the telescope. Simple then really!!
But ……
If we delve a little deeper we come across one of the biggest problems in modern physics. We have two major theories that were developed some 100 years ago which have stood up to every experiment test we have been able to conceive of – namely general relativity and quantum mechanics. Quantum mechanics describes exquisitely the physics of the very small, e.g. atoms. General relativity shows how gravity arises from the very fabric of space itself and explains how the universe works on large scales.
The big problem arises in situations where both theories are needed, i.e. massive objects where quantum forces are important for example a black whole. The theories then give completely nonsensical answers - something’s fundamentally wrong at the heart of physics !! Some of the greatest minds in physics have spent the last 100 years tying to produce a viable quantum theory of gravity and failed.
The answer needs to explain, among many other things why gravity is an incredible weak force compared to the 3 other know forces of nature. For example, a tiny magnet (driven by the electromagnetic force) can overcome the force of gravity generated by the entire earth!!!
Perhaps more on this at a later date!
Nice post Jim! As a former theoretical atomic physicist myself I also enjoyed your dip into the world of theoretical physics - it's a fascinating subject!
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