Butterflies, Credit Cards and Light Bowls

Hello there, skeptical friends, and skeptical foes,

I got my Scientific American today, Which is very surprising, because I thought it took about 2 weeks to send post from America to Australia, but there you go. I always thoroughly enjoy getting my Scientific American each month, and I always find half a dozen articles which I consider blogging for. I found an article today which was about some of the clever light tricks which animals play on us, but not about the colour changing squids which go black and then white and then black and then white when a pretty lady comes past or when a compeditor squid comes along. This article was about the microscopic patterns on bird feathers, butterfly wings and worms, which make colours which don’t look like what they really are. I will be blogging about a few of the tricky light patterns mentioned in this article in future posts, but today’s article is about A strange pattern found on Butterflies.

The emerald swallowtail butterfly lives in South-East Asia, and has a wing-span of about 8 – 10 cm, and is one of the most prominent butterflies in this area. They have a distinctive green and black pattern on their wings, and it has been discovered that the colour of the wing is not actually green, but it is a combination of blue and yellow colours.

The green parts of the wing are covered in tiny, bowl shaped dimples just a few microns across. The dimples are lined in layers of chitin which act as mirrors, which only reflect light of certain wavelengths. In the bottom of the bowls are chitin which reflect only yellow light, while around the top of the bowls are chitin which only reflect blue light.

Researchers at Georgia Institute of Technology tried to replicate this effect, with success. They created this pattern by first making a polymer, and vaporizing water, letting it condense onto the polymer, and letting the water droplets sink into the polymer, creating even, uniform, aligned bowls. They then microscopically dusted the polymer with layers of titanium oxide and aluminium oxide, and the result they turned out with was comparable to what was found on the butterfly. The researchers also found that under a polarizing filters, the yellow light from the wing and polymer pattern did not show, leaving only the blue light.

This polymer pattern could provide an extra layer of protection to credit cards and bank notes. A small half-inch square on every bank note and credit card, similar to the watermarks on bank notes in Australia , would add an extra layer of protection to the notes. All that would need to be done is put the bank note under a polarizing filter, and you would have an easy authentication check, adding to the layers of defense already present in notes and credit cards.

as can bee seen, nature has found simple ways of producing amazing colours and patterns, and as has been shown on so many scientific disciplines, physics, engineering, chemistry, technology, the best solutions to some problems were solved thousands of years ago, by a small bug that eats wood, or something of the like, and we just have to find out how to replicate them. That’s all I have to say. I will leave you with a quote from Carl Sagan, “Extraordinary claims require extraordinary evidence.”

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Red Flags to watch out for

I am going to start blogging every now and then on some red flags you can find to help you distinguish a pseudoscience from a real science. These are very important to learn and can help you to make a quick judgement on the reliability of websites or books or articles, without having to do a big scientific study or finding one that had been done to assess the validity of people’s claims.

I will start out by making a clarifying statement. Just because an article or ‘scientist’ displays some red flags in his reasoning, logic and evidence, does not make that argument false. The same goes for a logical fallacy. An argument can never be proven to be wrong, but if the only evidence for it is illogical and suspicious, then it should be disregarded.

The red flag I will be discussing today is one which is as much a difference between science and pseudoscience as it is a red flag. It is the hyping up of very flimsy evidence to prove ones case. This is what distinguishes the scientists from the cranks. I will give some examples.

A few weeks ago, I blogged about a great new battery technology which is able to generate power from the ambient heat from a person’s body, or a light, or the sun, or just heat which exists around us. Now this is a pretty amazing application of technology, but the scientists who were behind it played it down quite a lot. The same things happen with all of the great new discoveries in the search for the god particle, the Higgs  Boson. At one stage, late last year, there were a series of big steps made towards finally finding this elusive particle, and I was getting very exited about it, because they were very close to uncovering the particle. That was the opinion of most of the scientific and skeptical blogging community, and I got the feeling that the discovery was right around the corner.
But there were the scientists behind the discovery, just saying, “You know what, we are getting close, but we haven’t found it yet, lets just keep low and celebrate and dance when we finally uncover it.”
This is very humble of them, and it is very telling.

Could you imagine if a perpetual motion crank got a hold of evidence 1% as much of a breakthrough as that of the new battery? It would be all over the news, they would be asking for Nobel prizes, holding press conferences and they would probably be set for life.

This is a big red flag, if somebody is holding up their entire medical practice or ideology on one or two flimsy testimonials, and they are drumming them up like when man landed on the moon, then you should be suspicious. If somebody, however, is playing down a big scientific discovery, then you can probably lend credit to the reliability of the website.

I will leave you with a quote from Xi Zhi, “Large skepticism leads to large understanding. Small skepticism leads to small understanding. No skepticism leads to no understanding.” Xi Zhi, A Chinese Calligrapher of some note.

Another battery we will never see again?

Buenas noches,

Today’s post will be about an article I first saw at physicsworld.com. It is titled ‘Graphene in new ‘battery’ breakthrough?’, and when I first saw it, i had the normal reaction of “Here we go, another new battery technology which will be hyped up but we will never see on shelves.” but I decided to have a look into it, because sometimes there is some pretty interesting physics at hand. To be honest, there may be something to this, because once you see past the badly worded title, it is not your average battery article.

The difference between this battery and normal battery technology is a few things. It does have what all new battery technologies must have, larger battery lives, but it also has something which could be very useful in almost every situation, it is powered by the ambient heat in its surroundings.

Now, normally, when we hear about the latest battery technology, you can usually list a few good applications for it, but with something like this, the list would be shorter if you listed what it wouldn’t be useful for… like trekking in the tundra or living on Mars.

You may be asking, “How does this new battery work?”, well, I am going to explain it to you now.
It appears to be yet another victory for graphene. We are all familiar with ions, positively charged atoms. Well, when in an aqueous solution, ions move around with a whole heap of speed at room temperature. A lot of  energy can be produced just with the heat around us.

The experiments where conducted by Zihan Xu and his colleagues, and they made this battery by adding gold and silver electrodes to a strip of graphene (a sheet of carbon one atom thick). When putting six of these devices in series in a copper-chloride ion solution, they found that they could produce a voltage of more than 2V, this is plenty enough to power an LED light. It is an interesting concept, and is not yet at the stage of being able to run a car on it, but it is a limitless energy supply and it seems scaleable.

That’s enough of me for today, I leave you with a quote from Edward Teller, “A fact is a simple statement that everyone believes. It is innocent unless found guilty. A hypothesis is a novel suggestion that no-one wants to believe. It is guilty, until found effective.” Edward Teller, father of the Hydrogen Bomb and theoretical physicist of some note.