Brian Clegg's Blog, page 101

Colour conundrum

Have you ever thought about how strange a concept 'shiny black' is? Read on, in a post inspired by a Twitter interchange with Steve Mould of Festival of the Spoken Nerd. (If you haven't seen their show, book now - it's great!)

What colour is the car in the picture?
It's black.
Are you sure?
Of course I'm sure. What's your point?
It's black?
YES! Okay?
Bear with me. How do you know it's black?
Because that's the colour it is.
And how do you know what colour anything is?
This is basic Newtonian stuff, isn't it? White light hits an object. White light is made up of all the colours of the visible spectrum. Some colours are absorbed, the rest re-emitted. And the colours that are re-emitted are the colours we see. Trivial.
So a postbox, for instance?...
Exactly. White light hits a postbox, which absorbs everything except the red photons, which re-emit. And amazingly we see a red postbox. I still don't get your point.
You will. What about a black object?
That's a bit of a special case. We say something is black when it absorbs the whole caboodle. It doesn't re-emit any colours of light. So arguably black isn't a colour at all, it's an absence of colour.
Spot on. So what colour is the car in the picture?
Black.
And yet it is emitting light. It's shiny. And what does shiny mean?
Unless you are a Firefly fan, it means, well, something that shines. The OED says 'Full of light or brightness; luminous...'
So how can that car be black, if it is full of (emitted) light? By your definition, the colour of something is the colour of the light it gives off. What colour light does the shiny car shine with?
Erm, white light?
Exactly. So by your definition of colour, this black car is white. Next we prove that 2+2=16 and rip off the Bank of England.

Con-fusion

It's not surprising when the beam lines have to go through two of these
that a bit of energy is lost.
(Photo courtesy of Lawrence Livermore National Laboratory)I'm a bit embarrassed that the day after moaning about the Today programme's handling of a climate change story, I'm getting at the way the press dealt with a science story today. Some may rightly say something about pots and kettles.

After all, I am a science writer, and I get things wrong too (most recently calling the Harwell facility the National Physical Laboratory rather than it's true name of the Rutherford Appleton - though, to be fair, I think the Harwell lab probably deserves the title more). But the problem I'm describing is more about mainstream media misunderstanding the science, rather than a simple factual error.

The last couple of days, most of the papers have carried excited reporting of a breakthrough at the National Ignition Facility, the vast nuclear fusion site at the Lawrence Livermore lab in America, where they are experimenting with creating fusion for energy by zapping small amounts of material with vast lasers. Typical of the write-ups was the Guardian with 'Sustainable nuclear fusion breakthrough raises hopes for ultimate green energy'. They tell how have the scientists have achieved a world first by getting more energy out of the nuclear fuel than they put in.

What some of the other papers never mention, and the Guardian doesn't put up front, is that this is true, but not as good as it sounds. It's true they did get more energy out of the fuel than they put into it - but they got a lot less out than they put into the system as a whole, as the vast banks of laser amplifiers all lose a bit along the way. To be fair to the Graun, they did eventually explain this - but I think the way the story is structured doesn't put enough emphasis on it up front. And several other papers never even bothered to mention this bit at all.

However, that isn't really what I've got a problem with, so much as the timing. Most of the articles (including the Guardian one) give the impression that this break-through has just happened. But in fact it took place last autumn and was well publicised at the time. All that's happened now is that it has been written up in Nature, who have put out a press release about it and the journalists reacted to the press release, not the actual event.

Now I know many scientists don't particularly like information about experiments to be publicised before they have a peer-reviewed paper, but this was rather different. Either way, the result was, because of the press's obsession that they can only write about things that are immediate and current, rather than just because they are interesting (which this is), that the truth about the timing was carefully pasted over. And that's a bit naughty.

Why do they do it?

Would you buy a used weather system
from this man?I was listening to Lord Lawson on the radio this morning, doing his usual climate change denial thing (though he was being very careful to always refer to it as 'global warming', as the kind of weather we have at the moment is not one many would associate with warming). And in his voice was all the fervour of an old-time religionist. He knows that global warming doesn't exist, and he wants us all to share in his beliefs.

It made me wonder, why he believes something so fervently in the face of the evidence. By evidence, by the way, I don't mean the current flooding in the UK, though of course it may be indeed influenced by climate change. We can't deduce anything from a single data point. I mean the big picture. And when you think about it, his response is very similar to the way that creationists cling onto their beliefs that, say dinosaurs co-existed with humans and were on the ark in a great flood where the waters covered the earth, despite all the evidence the contrary.

It's also why people like Lord Lawson are the last kind of person who should be given a public platform on a subject like this - which wasn't helped by the Today interviewer who several times referred to 'the controversy.' There is no controversy among people who know what they are talking about - and it's interesting again that the interviewer was employing exactly the same term as the creationists: 'teach the controversy.'

As far as I can see, Lawson, who studied PPE, has no training to interpret scientific data, nor to pronounce on science, but away he goes with those typical denialist tropes, some of which I list here to help you spot them in action:
Use language that is misleading, like 'global warming' but never 'climate change'.Cherry pick data to show what you want it to show. So, for instance, point out that global temperatures haven't risen much in the last 15 years, but don't include why this would be expected with the current picture of climate change.Make statements that simply aren't true with such conviction that it sounds as if you know what you are talking about. Say, for instance, when an expert says 'During that time the excess energy is still being absorbed by the climate system,' respond with 'That is pure speculation.' No need to base your comment on any scientific data, even though the argument your are countering is based on measurement, not just theory. Just say 'That's not true,' or 'That's speculation,' loud enough and you will carry the day.Point out that the UK only contributes a small percentage, and say that therefore it doesn't matter what we do. Would he do this about anything else that was wrong, like hanging ex-politicians from lampposts? 'It doesn't really matter, as the UK only has 2 per cent of the world's ex-politicians.' That's okay, then.Say that scientists can't agree, or can't be definitive. This just describes the nature of science. But it doesn't mean we shouldn't go along with the best match science can give us to reality until better results come along. Why go with something that bears no resemblance to reality instead?Find some tiny example that seems to contradict the theory, while ignoring huge swathes of evidence that support it. I know this is cherry picking again, but this time it's extreme cherry picking.All I can say to anyone who is listening to Lord Lawson and thinking 'It must be true, he used to be Chancellor' is to consider whether you would take the same attitude in this situation. You are ill and you go to the doctor. A whole host of medical experts tell you that you need a particular treatment. Then Lord Lawson comes along (who knows as much about medicine as he does climate change) and says 'No, that's rubbish. There is no evidence you need this treatment. You just need to pull yourself together.' Would you really give him the time of day, or would you consider him to be irrelevant to the discussion? 
Enough said. I'm off for a ride on Walter, my pet dinosaur.
This has been a green heretic production.
Image from Wikipedia

Amazon dilemma

If there was ever a company it is possible to have a love/hate relationship with, it's Amazon.

The hate side is pretty straightforward, and the one that probably many of my readers could put forward. In fact the very mention of them will have some of you frothing at the mouth. They are a behemoth, flattening all opposition in their path. They fiddle their taxes. They drive bookshops out of business. They don't pay publishers (and hence authors) as much as they should because of their virtual monopoly. They set the rules and everyone else has to follow or get out. And they treat their low level employees like automata.

I really did write the bookBut actually, they are also pretty damned good at what they do. As someone who wrote the book on customer service, I have to grudgingly admit that most of the time they get it right in a big way.

Like the way that I can buy music from them and in many cases I can not only get the CD, but instantly download the tracks at the same time at no extra charge. Now you may say, 'Grandad! Why do you need the CD if you've got the download?' And I have to reply, 'Experience, young Jedi, experience.' When I first worked on PCs I twice lost a hard drive before I realised backing up was a good thing (I mean the drive failed, as early ones tended to - I wasn't careless enough to actually lose them). If you can get a backup for free, then it's well worth having.

Another example. On Saturday morning I ordered a household product from them. Because I'm one of their 'Prime' customers I get free next day delivery - which itself is a brilliant thing, because it puts online shopping more on a par with the old bricks and mortar version. But of course, we all know that on Saturday, 'next day' means Monday. Nope. It was here, at my house, before 11am next day - Sunday.

And then there's returns. A couple of times I've had to send something back and they make it very easy. They even send out the replacement before you put the original in the post.

So, yes, they may be evil. Yes, they plan to take over the world.. But they are so seductive, like all the best baddies. I don't think I can give them up.

If you want to read more about Amazon (and the secrets of what they get up to), with useful timing, part way through writing this, I got a link to this interesting, if immensely long, article Is Amazon Bad for Books in the New Yorker magazine, from the lovely Lynn Price at Behler Publications.

How not to run a phishing scam

There are some evil people out there who prey on computer users by pretending to be their banks etc. Luckily for us, the people who run these phishing scams are often not very bright. The other morning I received this email:


Oh, dear, I thought, what a shame I can't receive that £265.93 as I don't have a NatWest account. Silly old bank. And fancy them not spotting they should take the fee off, rather than add it on. Doubly silly old bank.

But then, the very next email in my inbox was this:


Now, call me suspicious, but finding out that exactly the same amount, with exactly the same transaction ID (and exactly the same negative fee) was also being applied to 'my' Barclaycard account was teensiest bit worrying. Especially as the format of the email was identical. Then I looked at the next email.


Oh, come on now. This is taking idiocy to a new and rather dizzy height. It's surely not phishing at all, but a form of performance art, designed to bring a smile to my face first thing in the morning. 
And if that was the intent, it certainly worked.

In Apple Blossom Time review

At first glance I am the last person to be part of the target audience of In Apple Blossom Time by Robert Wack, set in 1944. I hate war films (or rather I have never seen one and never particularly want to). I even avoided War Horse because of the setting. As for written material, the last time I read anything set in the Second World War it was a comic back in the 1960s (usually, as I remember it, involving daring raids to blow up a submarine pen) when there was still a considerable appetite for gung-ho WW2 stories. But this is different.

I'll admit it appealed to my vanity that the author claimed to be inspired my book How to Build a Time Machine to create a novel around the extraordinary war career and death of Dutch-American mathematician Willem van Stockum, one of the first to take on the implications of Einstein's work on general relativity that implied the possibility of using warps in spacetime to create closed time-like loops that should enable travel backwards in time.

I can't deny I found the book gripping. I expected to read bits of it as and when I had a bit of time between research reading for my next book, but in practice once I started, Apple Blossom took over and wouldn't let me put it down. If you are going to be picky, some of the dialogue is a little stilted and there are too many pages given to introspective thought, but the wartime scenes, both van Stockum's experience as a bomber pilot and the scenes on the ground in Normandy in 1944, are well-crafted and place the reader uncomfortably deeply into the action.

The book would have been quite interesting if that were all there were to it, but it is lifted to a new level by the inclusion of mysterious figures, some who appear to be trying to save van Stockum from his 1944 death, and others to prevent this interference. Van Stockum's impact on the physics of time travel would, it seems, have repercussions in the future, if he can continue his work after the war.

Technically there is a flaw in the approach taken to time travel here, as no device reliant on general relativity to travel backwards in time could reach further back than when the machine was first created, but I am always sympathetic to the argument that in science fiction the most important word is 'fiction' and it while every effort should be made to stick to known physics, if necessary the detail has to give way to making the story work. Apart from the violation of what I think of as the 'cardboard box of time effect' (more on that another time) the author does pretty well at keeping the science on track.

It won't appeal to everyone (and if you find the first couple of chapters confusing, bear with it), but in the ebook form you can try before you buy, and I recommend giving In Apple Blossom Time a go. It is available from Amazon.co.uk and Amazon.com. The book will also be available in print later in the year.

The compound of regret

On the whole I find pretty well every compound I cover in the Royal Society of Chemistry podcasts quite interesting, but today's is a bit of a beast. Prepare to meet acetaldehyde, which some blame for your hangover.

So grab yourself a glass of Irn Bru and hurry over to the RSC compounds site to see more on this painfully fascinating substance (posted 22 Jan). If you'd like to listen straight away, just click here.

Warped vision

The typical movie jump to hyperspaceIf there's one thing science fiction movies can agree about, it's that heading towards the speed of light, and or engaging warp drive should make for some interesting special effects. Often stars elongate, sometimes they change colour, sometimes they disappear with a bang.

The reality is not quite so visually exciting, but it is still impressive and decidedly confusing until you  think through what is happening.

As a ship accelerates towards the speed of light, two things should happen. One is that there will shifting of colours. The colours of the stars behind the ship will be red-shifted, moving down the spectrum and those in front will be blue-shifted, moving up. This means that some stars will disappear as their colour goes out of the visible range, while others will pop into visibility for the first time.

The second thing is that the stars will move towards the front of the ship, bunching up in the direction of flight (though still as points, not the traditional movie streak). As the ship gets close to light speed, even stars that were almost directly behind it will appear in front. This is the least intuitive aspect,  because it seems more natural that the starlight will be 'left behind' than brought to the front. What you have to bear in mind is that while the light was travelling from a particular point, you will have moved with respect to it. Add in the relativistic complication that light continues to travel towards you at the same speed whatever speed you are moving at and you end up with the bunching effect - it just remains very difficult to envisage. This website may help.

Things get more messy when we enter warp drive, whatever than means, as what you see is likely to depend on the mechanism of the warp drive itself, and since they are almost all imaginary, it's really rather up in the air. This website suggests that it would basically be more of the same - that in the warp bubble envisaged for a real warp drive you would see the same effects as when nearing the speed of light (but even more so). However the environment of a warp drive is quite different from a ship travelling at near the speed of light. Technically in a warp drive, the ship isn't moving at all, it's space that is moving around it. And once you get into the more dramatic science fiction concepts like hyperspace it isn't at all clear what the implications would be - quite possibly, there would be no stars visible at all.

There is always a tension in science fiction movies between getting a good representation of the best science tells us and making the film work as a piece of storytelling. Often the reality is ignored due to ignorance or a misapprehension of the audience response. As I mentioned recently, I think the silence of space worked superbly in 2001, and yet practically every movie since has given us sound in a vacuum. In the end, the Star Trek/Star Wars whoosh of stars as warp/hyperdrive is engaged and similar effects probably don't do any harm (though I here and now put a scientific curse on any movie or TV show that portrays a star field that moves visibly past as the ship flies), if only because the technology is fictional. But it doesn't do any harm to ponder it.

Image credit: University of Leicester via space.com

The myth of the friendly newsagent

My corner shopI was listening to a piece on the radio the other day on the way home from the STFC (not a football club - but that's a different story). The piece was bemoaning the rate of closure of local newsagents. 'We are losing a vital local resource,' they said. Are we? Are we really?

Don't get me wrong, I'm all in favour of local enterprise and such, but are the typical local newsagents all that wonderful?

As I've mentioned before, my local corner shop, 5 minutes walk from my front door, is a massive 24 hour Asda superstore, alongside the likes of Marks and Spencer, Next and Starbucks, so I'm not exactly typical in local provision. But I've had plenty of experience of local newsagents in the past, and I really can't see what all the fuss is about.

Those on the programme, bemoaning their loss, had two principle arguments - that the local newsagent gave better customer service than a supermarket, and that mostly they are being replaced by 'metro' or 'express' versions of supermarkets, i.e. diabolical large companies, worming their way into the neighbourhood, rather than friendly locals.

I know there are exceptions - but I think in most cases this is not a viable comparison. Yes, I have known one excellent corner shop/newsagent/post office - to be precise a village shop, where the service was very good. But frankly many of the newsagents I go into are dingy and unpleasant, and have surly staff who haven't a clue about customer service, other than taking your money. Oh, and they are expensive to shop in. By comparison, our nearest supermarket 'local' (which I admit I don't use much because it's further to walk than the hypermarket) is bright, clean and relatively cheap. And in my experience the staff are just as friendly, if not more so.

For that matter, I don't really do small talk. I find it embarrassing and irritating with people I don't really know want to act as if they know me. Of course I like to chat to friends, but these aren't friends. I really don't want to have a conversation, I want efficient, quick service. (Which is why I frequently use the self service tills.) But I'll put that down as my failing. I know a lot of people do like to speak people. But the 'better customer service' argument simply doesn't hold water.

Of course you can't really argue against the 'big evil supermarket' bit. I'm no fan of Tesco, say, as a company. However I'm not sure there is more social benefit to be had by contributing to the coffers of one family rather than the many more people who work in a supermarket 'local'. And in the end it is a financial transaction, not a social service. I would like to be able to make that transaction with whoever does it best, not based on a personal bias against a large company.

So are we really losing a hugely valuable local resource when a local newsagent closes? I'm really not sure we are.

Selective tree hugging

Picture from Mike JuppI was interested to see this graphic on Facebook the other day. I was impressed by the statistic - and it makes a lot of sense. Tear out a load of trees, replace them with housing and tarmac and you are going to get an awful lot less water taken out of the system, inevitably increasing the flood risk.

As always when I see such numbers, though, I feel the urge to check the source, as I am afraid as many as 91% of statistics found on the internet are either wrong or simply made up.*

I have struggled to find anything other than people repeating the 50 gallon figure without sources (though I'll come back to how realistic it is), but I was fascinated to discover this piece of research by the Forestry Commission. Although it doesn't directly confirm the 50 gallon figure, it does (not surprisingly) confirm that trees are about the best thing you can have to reduce water run-off. But the reason I found it fascinating was the detail, looking at different kinds of trees, because it underlines the problem I often have with the green movement.

There is often a tendency to confuse what is 'natural' or sounds more green in a 'hey, let's hug the trees' hippy way with what is better for the environment (this comes through, for instance, in all the myths surrounding organic food). In the UK there is no more natural symbol of a tree than the oak tree, but it's actually not the best tree to reduce flooding. In fact, conifers are significantly better than broad leaf trees like oaks at putting water back into the atmosphere. They also have the advantage of being much quicker to grow. It's all very well for 60-year-old oaks to 'drink' up to 50 gallons, but we haven't got 60 years to wait for new trees to grow. Yes we should preserve existing oaks (which, to be fair, was the point of the graphic), but we should not be planting new ones if this is our aim.

I find this particularly interesting because on the whole the dedicated green types are likely to frown on conifers as being unnatural and not as good as the 'native' species. But if you truly care about the environment, we need a lot more conifers.

I said I couldn't directly confirm the water consumption figure, but I can do a Fermi calculation. Broadleaves achieve between 400 and 640 mm of evaporation from 1 hectare of forest receiving 1000 mm annual rainfall. Let's use the median of 520. The current moving average annual rainfall is about 1175 mm, so that pushes up the consumption to 611 mm/hectare. A typical oak tree is about 13 metres across, so realistically you could get about 40 per hectare (which is 100m x 100m) in a well-covered forest. So the annual volume of water one broadleaf disposes of is 8109942 cc or 81099 litres. That's 222 litres a day, which is 48 gallons. Of course that is all back of the envelope stuff, but it's good enough to see that 50 gallons per day isn't a bad figure.

* If I am honest, this is one of those made up statistics. I picked the number 91 at random. However, because I used the statistical weasel words 'as much as' I am pretty safe, as this basically means anything between 0 and 91. (The same goes for 'up to' which you will see elsewhere above.)

This has been a green heretic production