Saturday, 18 February 2012

Second ride in a week; I'll get spoilt!

When the rain this morning cleared I decided to jump on my bike. As the other day there was a steady wind, but it was a little less strong. I climbed up Loxley Valley to High Bradfield, already feeling I was in the countryside with the fields and reservoir in the valley to my left and the hills climbing to my right. I swear that at one point I saw three donkeys in a field chasing a rabbit. At Bradfield I decided to turn right, up the hill toward Bolsterstone, but found I was somehow still going directly into the wind. Apparently it's a local phenomenon; it's said that every cycle journey in Sheffield is uphill in both directions and into the wind. Still, a lovely climb, the wind bracing but not too cold and the moorland beginning to open up on my left. It's a huge area with no roads across it (huge for England, anyway!) nothing but some footpaths and bridleways cutting across the bleakly beautiful moorland - Hobson Moss and Howland Dean, Pike Low and Candlerush Edge, Nether Hey and Alport Dale and Bleaklow Stones - dropping down to the triple reservoirs of Howden and Derwent and Ladybower (where the Dambuster squadron practiced their flights) before climbing again, over the thousand tiny valleys, called cloughs, that drain water from the rocky loam, until you get to the small town Glossop.

You can ride many of the paths, although it's tough going and, as most are narrow, I prefer to not do it on a saturday afternoon when there are likely to be plenty of walkers, and once committed it is a long tough ride with few chances to turn off and turning back even harder. So I carried on up the road until I found a bridleway cutting sharply down on my right, a chance to let loose on a bit of off road downhill. Mostly farm track, so fairly solid, the trail dropped and wound for perhaps a kilometre before depositing me on one of the beautiful narrow, winding roads that wind along the valley side, mostly through light woodland, occasionally clearing to give a view across the valley.

I followed it around the top end of Broomhead reservoir (we have lots of them around here, gathering the rainfall that forms those many brooks and cloughs into lakes to water towns and cities for many miles), then the steep climb up the road to the tiny, beautiful village of Bolsterstone, famous for its Male Voice Choir. The last time I came up that hill my rear mech snapped off (less painful than it sounds) so I mentally crossed my fingers, but made it without any problems. Then a rolling stretch between dormant fields before dropping down to cross the first major road since I started. After waiting out the traffic from both directions I took the sharp climb, aided a little by the wind behind me, although at this point the sun had vanished and the wind carried sleet. Toward the top I could see curtains of it driven by the wind along the valleys behind me, the hills receding into grey distance.

This road lead me to the market town of Penistone (the derivation of which means “hill farm”, apparently – although there is a sculpture off the High Street that does look remarkably like a stone... anyway). I considered carrying on toward Holmfirth to see if, now that Last of the Summer Wine has finished, its streets are still thronged with busloads of visiting pensioners. Instead I joined the Trans Pennine Trail, part of the national cycle network that crosses the Pennine Hills, which would take me back, first along the bed of a former railway line (including a tunnel), then through my regular stamping ground of Wharncliffe Woods. For the first time on my ride I saw some other cyclists – young lads pushing their full-suspension monsters up the hills in Wharncliffe to hurtle down the steep, muddy, rock- and root strewn trails with the kind of disregard for danger you only get at that age. I didn't switch from a road bike to a mountain bike until my twenties, so missed out on developing the necessary lack of fear you need to do this. Note that they were pushing their bikes up the hill, though, while this forty year old was riding his.

At the end of Wharncliffe where the cinder roads end, I usually cross the road and nip through Beeley woods, to sweep down some nice slopes amid the trees which brings me to within a couple of kilometres of home. But those paths are rough and the melt and the morning's rain would have left them slick and muddy. While I probably couldn't get much dirtier I decided to drop down the hill to Oughtibridge to take the easier route along the main road, toward the lure of a shower and coffee.

Tuesday, 14 February 2012

First bike ride in far too long

After a busy morning I decided to make the most of the mild weather and head out for a ride. After I'd turned up Kirk Edge Road at the village of Worrall, though, I was suddenly riding into a steady wind - and as it was already a grade 15 climb, I decided to turn North rather than continue out to Bradfield. It is actually a nicer ride that way, heading up the intermittent climb of Onesmoor Bottom before slinging down the winding road toward Broomhead Reservoir. Climbing up Onesmoor it was getting increasingly cold above about 300-350 metres, with patches of snow still on the ground and a light but cutting wind that made me regret not gloving up. The fields up here are a mix of cereal crops (currently fallow of course) and hilly meadow, with herds of dreadlocked sheep and some beautiful horses. A creamy white and a piebald brown were having a race around their field, perhaps for the joy of running or perhaps to keep warm. Then the narrow road suddenly winds and drops down into the woods, to both sides jagged lumps of rock and fallen trees covered with a thick green moss that would look positively tropical if you couldn't feel the cold. I'd usually follow the road all the way around the reservoir and then climb up to Bolsterstone, but spotted a path cutting through the woods so decided to make the most of the quiet and the (mostly) frozen ground. A lovely sharp drop down through the woods, losing a hundred meters of altitude in not much more distance, then the following the path beside the reservoirs - winding and bumpy with roots and the uneven topography of the shore. Back on the main road at the bottom of the valley, and a sprint the last seven km home for a nice hot coffee.

Tuesday, 7 February 2012

The wonder of understanding; a review of The Fabric of The Universe by Brian Greene

Glancing at the reviews for Brian Greene's overview of how we view the stuff of which our universe is made, it seems that some people base their rating and opinion on how much they agree with the science, or how credible they find it. While I have read a fair few popular science books – especially in the areas of physics and cosmology, areas I find utterly fascinating and about which I am perplexed that anyone can not be astounded and beguiled – I have to assume that I am reading a fair explanation of facts and theories. That is not to say that I assume the author is more knowledgeable than me simply because he has more letters after his name, but because he grounds his claims with background and the weight of evidence that is needed for a scientific hypothesis to become a generally accepted theory. Also, I have taken the effort to educate myself in these areas so have enough grounding myself to be able to appreciate the arguments.

That said, for much of this book I'm unsure how much background would be needed to understand the explanations. Greene writes with a clarity and readability which is all too rare in any field, and is particularly welcome in discussing such big ideas. As in Stephen Hawking's The Grand Design, Greene completely dispenses with calculations but, unlike Hawking, he also tries to keep the use of metaphor to a minimum. It cannot, of course, be dispensed with – metaphors are an extraordinarily powerful descriptive tool, especially in a field that can only properly be explained and understood using specialist mathematics – but for the most part Greene simply gives an overview of each field in historical context, and explains WHY it is important, what it explains and why it works.

He starts – as modern physics in so many fields must – with Isaac Newton, and particularly Newton's Bucket. If you hang a bucket of water on a rope and twist the rope, as the rope unwinds, spinning the bucket, at first the water remains stationary until the friction of the bucket's movement makes the water begin to spin. When it does, the surface becomes increasingly concave, moved outward by what why now call centripetal (or centrifugal) force. But what, asked Newton, is the water moving away from, or toward? What is it moving in relation to? He decided that it moved in relation to the fixed fabric of the cosmos, the stuff in which the matter (that he recognised as being the thing on which gravity works) sits. Recognising that he had no way of testing this medium by experiment, Newton took this is an immutable absolute and left it at that. Greene keeps returning to the bucket and its implications throughout the book, to superb explanatory effect.

I won't go further into the details (read the book!), but simply say that thanks to Professor Greene I now understand areas of cosmology and physics where I had previously had to simply give in to brain cramp and accept as being true. I understand why the speed of light (actually, the speed of any electromagnetic radiation) is approx 300, 000 km/sec faster than you, no matter how fast you are travelling. I understand a whole lot more about General Relativity and Quantum Mechanics, and why they make sense and are such powerful tools in describing our universe. I understand that Inflationary Theory is not merely a tweak of Big Bang theory to enable it to fit observed facts, but a whole new way of looking at the growth of the universe that actually explains much more about the fundamental physics.

I'm not claiming a thorough understanding of these subjects (and in some, like Brane Theory, I still found myself rather lost; a re-read may be in order), but I feel that The Fabric of the Cosmos has deepened my comprehension of and appreciation for the wonders of our universe. And for the wonders of the human mind to work out these things. In around three hundred years we have developed this system, science, as a means of examining the world around us in a way which is comprehensible to anyone who is willing to put in the work. All books on science now seem to feel the need to restate this about science; it is NOT knowledge passed down from on high by men in white coats using deliberately obfuscatory language for reasons of either professional pride or conspiracy. Science is a method that enables us to understand more and more about the world, to revel in the joy of knowing how the rainbow is formed as well as in its simple beauty. No idea in science is sacrosanct, no theory is holy. To achieve the status of acceptance of say, General Relativity or Evolution by Natural Selection, a theory has to be tested – that is, it has to survive again and again and again the onslaught of people systematically trying to prove it wrong. When a weakness is found the theory must be re-examined. Sometimes the fault will cause the foundations of the theory to crumble, and it will be discarded; it has still served a purpose, to show how promising such an approach is. Sometimes finding the errors will strengthen a theory and teach us more – Edwin Hubble's original calculations of distant galaxies seemed to show the universe to be about 1.5 billion years old, despite lots of other evidence at the time insisting it was at least 3 billion years old (as we now know, this was still almost five times too conservative). Everything else about Hubble's observation and theory made sense, there was simply an error in calculating the distance of the super novae he was using to get the figures, a correction which itself taught us much about the universe.

And this is incredibly important to realise because, while many theories, however much work they take, partly make sense on an intuitive level you get to Quantum and Brane theory and they simply cannot – in fact they seem, by intuition and everyday experience, utterly ridiculous (the great physicist Nils Bor said something along the lines of “if you think you understand Quantum Theory, you don't understand Quantum Theory”) but they are undoubtedly right. One important way a theory is tested is to use it to make predictions in the physical world and Quantum Theory has been called far and away the most successful predictive theory in science. It is, like every successful theory, one that accurately describes the way our universe works, with the limits of perception and understanding we have, which is why theories are modified or discarded when new information comes along. Which is why General Relativity replaced Newton's Laws of Gravitation as the best description we have for how gravity works – although NASA still use Newton's calculations most of the time, for the same reason you don't need to understand Gaussian Quadratic Maths to balance your chequebook.

Greene's book, the first I've read by him, shows why it is worth reading a range of books on the same (or closely connected) areas of science. While in The Grand Design, Hawking and Mlodinov managed to convey a sense of wonder and discovery on a par with Carl Sagan's writings (a plaudit I don't throw around lightly!), Greene has given us a book that manages a clarity and depth of explanation while being a thoroughly entertaining read. At schools, perhaps instead of training our children into narrowly defined roles, science classes should just be introducing them to the works of Greene and Hawking, Sagan and Tyson (Neil deGrasse, not Mike) and Krauss to show them how huge and wonderful and beautiful the universe is, and how much joy and fulfilment can be achieved through our efforts to understand it.