It is a timely coincidence that today’s Daily Grind falls on New Year’s eve; a perfect opportunity to reflect on how the year has been and to think about the future.
The first thing to reflect upon is the fact that, since starting Bean Thinking in autumn 2014, I have had a great excuse to get out and try many interesting independent coffee shops and tea houses. Obviously there are many more to try and so something to continue with in 2015, but what matters to me is that they are independent. It is an interesting question, at what point does a cafe with multiple branches turn into a chain? Perhaps this is something to worry about another time, for the moment there are still a great many to try (both old and new) that I don’t need to worry about it for a while.
Do you see a wood or the trees?
Then there has been the opportunity to encounter some very interesting people who, it is fair to say, are quite obsessed with coffee. Some of them are interested in different ways to make the coffee taste good. Some are interested in areas where coffee meets art (3-D latte art anyone?). There are those who are interested in the science of coffee and then those who try to ensure that everyone, from grower to consumer inclusive, gets a good deal for the coffee. In short, science, art, philosophy and coffee. In many ways it reinforces my opinion that a good education is far more than a mere qualification in a narrow specialisation. In the book “History and Philosophy of Science”, LWH Hull suggests an analogy to help us to understand our contemporary tendency to specialisation. Hull suggests that those who specialise are like people exploring different trees. We cannot understand another’s tree by stopping our work (of climbing our tree), and instead climbing “a few feet” up the tree of another. Hull instead suggests that by understanding the history and the roots of our own field of specialisation we can understand that others have similar roots, similar motivations and are seeking similar ends by different means. Understanding our own tree and appreciating how it has come to be, allows us to appreciate the trees of others and thereby allows us to see the wood instead of the trees.
So Happy New Year to all, feel free to leave any comments about art, social justice, science, in fact, anything that you think coffee related and vaguely relevant to this start of the year. I look forward to ‘meeting’ more of you and hearing what you have to say in 2015.
Adoration of the Magi, Andrea Mantegna, 1431-1506. Digital image courtesy of the Getty’s Open Content Program.
There is currently a very thought provoking painting on display at the British Museum (although it will soon be gone, the Ming: 50 years exhibition, of which it is a part, ends on 5th January). The painting depicts the moment that the three kings, (or three wise men) present their gifts of gold, frankincense and myrrh to the Christ child. The three kings are on the right of the picture. Notice Melchior however, who is presenting gold to Jesus at the bottom of the painting. He presents his gold gift in a porcelain cup. The painting suggests just how valuable porcelain was to the Europeans of the 15th-16th century.
For many years, the Chinese had the monopoly on porcelain production and they ensured that the recipe was kept secret. Nonetheless, by the 17th century porcelain was being traded with Europe and by the 18th century the Europeans had started to mass produce it. Bramah has argued (in the excellent book “Coffee Makers”) that the explosion in popularity of tea and coffee drinking in Europe during the 17th-18th century was due to the introduction of porcelain into general use and its mass production. So it is worth taking a closer look at one of the key figures in the production of ceramics: Josiah Wedgwood.
As a ceramics maker, Wedgwood (1730-1795) was interested in ensuring his pottery came out of the furnace well each time and to do that, he realised that he had to know the temperature of the oven. Other pottery producers of the time judged the furnace temperature by the colour (red hot, white hot etc), Wedgwood asked if there was a better way. Eventually he designed a “pyrometer” (“fire” meter) made from bricks of Cornish clay. Wedgwood used the fact that the clay shrank when fired. The amount that the clay shrank indicated the temperature of the oven. Wedgwood could then quantify what was “red” hot etc. Of course, there were problems. Wedgwood’s thermometer worked at temperatures of around 1000ºC, where ordinary alcohol or mercury based thermometers could not be used. How can the temperature scale (that became known as degrees Wedgwood) be correlated with the temperature scales that we are familiar with (such as degrees Centigrade)? Another, perhaps more significant problem was that the technique was not transferable to other practitioners, different clays shrank by different amounts. The Wedgwood scale required a specific Cornish clay. It was left to Louis-Bernard Guyton de Morveau to improve the pyrometer, basing his high temperature thermometer on the expansion of platinum. Today, we use devices based on electrical properties of metals to measure such high temperatures.
If you are in London, it is worth popping along to the Ming 50 years exhibition before it closes on 5th January 2015. Along with this painting, there are many examples there of excellent Chinese porcelain. One of the things that struck me as I went around the exhibition was just how annoyed visiting European diplomats must have been if they ever visited the Imperial palaces. Not only did the Chinese use this rare and valuable porcelain for cups, they also made exquisitely designed, porcelain, floor tiles and bird feeders. While in Europe we were struggling to make any porcelain, the Chinese were not only walking on bits of this valuable material, they were allowing their birds to feed from it too! An interesting history for next time you take a sip from your favourite mug.
Please leave any comments using the form below. I am very grateful to the image reproduction polices of the British Museum and the Getty Museum for the images shown in this article. Information was taken from:
It is said that Beethoven prepared his coffee by counting, precisely, 60 beans per cup. Biographies of Beethoven certainly suggest that he had a significant coffee habit. Banned by his doctor from drinking coffee towards the end of his life, there are many references to him frequenting coffee houses in earlier years. Sadly, I have not found the source for the 60 beans story and so would not like to comment on its veracity. Nonetheless, it is a good story and it does link with coffee so, as today (17th December) is the 244th anniversary of his baptism (it is assumed that he was born the day before on 16th December 1770), it is “Beethoven day” on the Daily Grind.
To me, what lends some credibility to the 60 beans story is the fact that, as coffee lovers, we can be very particular about the way we prepare our brew. Some people, for example, weigh the amount of the coffee and the quantity of water and brew their coffee according to instructions from one of the various online brewing tutorials (see here for a good one from Hasbean). Personally, in the morning, I am far too bleary eyed to consider getting the kitchen scales out, nor would I count a certain number of beans. I do however count the number of seconds that I take to grind my coffee with my trusty burr grinder (always set to the same level of grind of course). Can counting the number of seconds for a quantity of grind possibly be a good way of measuring a specific quantity of coffee?
Did Galileo drop balls from the top of the tower?
Galileo Galilei (1564-1642) died before coffee was properly introduced to Europe. He is relevant to this story though owing to his work on clocks and timing devices. One way that Galileo measured time was to collect water in a jug over the measurement period. It seems that this is almost the reverse of my morning coffee ritual. To check that he was measuring time correctly however, he needed a second, independent method. Of course, Galileo couldn’t use a watch or pendulum because watches hadn’t been developed at the time and Galileo himself was doing the work needed to understand pendulums and make them useful for clocks. So what else could he use to measure time? There is a clue to another method that Galileo used in his experiments on falling balls. Although there are questions as to whether Galileo really did drop balls from the top of the Tower of Pisa, we do know that he did experiments which involved rolling bronze balls down a groove. Along the groove were marks where strings made from gut had been pulled across the groove such that they made a sound as the ball passed, perhaps like the sound of a harp being plucked. By adjusting the position of these strings, the interval between the sounds from different gut strings could be made to match a known rhythm. The time it took for a ball to fall down the groove was being measured by matching its descent to a known tune. This suggests that Galileo sang while he was making his key measurements and that it was this that allowed him to start to understand how bodies fell under gravity. Singing was Galileo’s (surprisingly accurate) method of measuring time.
Which brings me full circle back to Beethoven. Beethoven certainly knew the “mechanician” Mälzel who invented the metronome as we now know it. There are also indications that Beethoven was aware of early versions of Mälzel’s invention. In 1813, the Wiener Vaterländische Blätter wrote “…Herr Beethoven looks upon this invention as a welcome means with which to secure the performance of his brilliant compositions in all places in the tempos conceived by him, which to his regret have so often been misunderstood“. It seems that in the two hundred years between Galileo and Beethoven, there had been so many improvements to clocks and timing devices that singing, which had started off as a way to measure time, was now itself being regulated by the clocks that singing may have helped to develop.
How many beans go to make your morning coffee?
So how is a Beethoven coffee, assuming that there is any veracity to the legend? Sixty beans works out as 8-10g which, depending on the amount of water in the cup could be weaker (or stronger) than modern brews. In my cup, it was slightly weaker than I am used to. I enjoyed my “Beethoven coffee” while listening to his String Quartet Op 74, “Harp”. As I sipped the coffee while listening to the first movement, I could almost hear the gut strings of Galileo’s experiment being plucked as the balls rolled by. The coffee itself (Costa Rica, Finca Arbar El Manatial, Yellow Honey, Caturra/Catual) was very smooth and rich, as you would expect from a coffee from Has Bean. Described in the tasting notes as “….An amazing caramel and milk chocolate sweetness partnered with delicate peach and apricot acidity…” It was the perfect coffee to enjoy with the Harp quartet piece. Sometimes it is important to take time to go slow and enjoy the coffee.
So why not raise a mug today to Beethoven and savour a Beethoven coffee? Please leave any comments using the form below, especially if you know a reliable reference to Beethoven’s coffee habit or have suggestions as to how to improve my morning brew.
Further reading:
Quotes taken from “Thayer’s life of Beethoven”, Revised and Edited by Elliot Forbes, Princeton University Press, 1967
Information on Galileo and time: “Styles of Knowing, A new history of science from ancient times to the present”, Chunglin Kwa, University of Pittsburgh Press, 2011
Taken at Brew & Bread, One City Mall, Subang, KL, Malaysia
Pop into any cafe and order a latte and chances are you’re going to see some great latte art. With the number of good baristas around competing to produce the best and most consistent latte art, it is easy to see some good art while waking up of a morning. Brew & Bread is a cafe with a couple of outlets in Kuala Lumpur in Malaysia. One of their customers sent me these images of their latte art (via Bean thinking on Facebook), which I think are among the finest examples I have seen of latte art being served, as a matter of course, at cafés. Apparently the people at Brew & Bread take their latte art very seriously, so if you find yourself in One City Mall, Subang or Kota Kemuning in Kuala Lumpur, do take the opportunity to pop in.
Not being a barista I can only guess at the skill that it takes to produce such great images as those at Brew & Bread. As a scientist though I can see some connections between latte art and copper mining. Or rather, the link between good latte art and bad copper mining (and vice versa). How? It’s all about the bubbles.
The small bubbles in the foam on the left trap coffee between them. The larger bubbles in the foam on the right allow coffee particles to drain by gravity and don’t trap them so well.
Now, I am on dangerous ground here because I have no experience in making latte art, nor really in steaming milk, so I hope that any baristas out there will leap in and leave comments if I have something awry in my description of how latte art is sustained. However, from various videos and how-to’s available online it seems that a key component for good latte art is making the milk into a micro-foam; a ‘velvety’ structure of tiny bubbles. From a physics perspective this makes sense. As the milk is first introduced into the espresso it picks up the crema on the espresso and captures the coffee-liquid mixture between the surfaces of the bubbles of the froth. A large number of very small bubbles will trap the coffee liquid and particles around the bubbles very well (see diagram). If the milk has too many large bubbles, not only will the mouth-feel get affected, the coffee itself is not held and trapped so well within the bubbles. When the art is about to be created, the barista slows the rate of pouring such that the coffee does not get pulled up with the milk and instead the milk foam is allowed to float on top of the espresso where it remains white. It is this contrast between the trapped coffee in the fast-poured milk and the pure milk of the more slowly poured milk that leads to the contrasts of what is known as latte art.
The bubbles get larger as they move higher up in a foam column. Shown here in a narrow glass of Corsendonk Agnus (beer)
Now consider copper mining. It is an unfortunate fact that we as a society are very reliant on mined products including copper. Copper is the backbone of our electricity network meaning that if you are reading this at all, you are relying on copper that has been mined somewhere in the world. Mining is a fact of our modern way of life. The question is how to reduce its environmental impact to a minimum. One way to minimise the environmental aspect of mining would be to ensure that it is as efficient as possible. Copper is often found in two forms, a relatively easy to extract oxide and the sulphides of copper which are harder to extract. The ‘froth flotation’ technique has been developed to maximise the extraction of these sulphides by using a foaming vat in a process that is the exact opposite of latte art. The copper sulphide rocks are ground until they are very small (around 0.05mm diameter) whereupon they are reacted with chemicals that make them hydrophobic (resistant to bonding with water). Other particles and rocks, that are mined together with the copper sulphides, do not react with the chemicals and so are less hydrophobic. The resulting ‘grind’ is mixed into a slurry and then introduced into a chamber which is aerated to form bubbles. As they are hydrophobic, the copper sulphide particles attach themselves to the newly formed bubbles to reduce their contact with water. The bubbles are then carried up through the chamber, taking the copper with them. The small bubbles at the bottom of the vat trap a lot of water and waste material between them. As the bubbles move upwards through the vat, they get larger (by combining with each other) and, whereas the copper sulphides, which are chemically attached to the bubbles remain with the larger bubbles, the liquid and waste material drains out towards the bottom of the tank. The copper products can then just be skimmed off the top of the vat. Unlike latte art, larger bubbles are useful in froth flotation in order that particles do not get trapped between the bubbles. What is good for the copper mining is bad for the latte art and vice versa. The more we know about the bubbles in foams (in both latte art and froth flotation) the more efficient and the more aesthetically beautiful our world can be.
Art for Christmas, another piece of great latte art from Brew & Bread
I would be very interested to know your thoughts on why a microfoam is needed for good latte art or indeed, any aspect of latte making. Please do feel free to share any good photos of latte art (or cafe recommendations) either here in the comments section or on Bean thinking’s Facebook page. There will be another latte art article in the New Year so new photographs (or cafe recommendations) would be greatly appreciated.
With special thanks to Oh Ying Ying for the photographs from Brew&Bread.
The sign board at Esters. Note the zig zag underline
As a website based on the physics inside a coffee cup, it was only a matter of time before I visited Esters in Stoke Newington. The name has significance to anyone interested in the physics (or chemistry) of coffee and the signboard outside the shop confirmed it. Under the name, there is a zig zag underline that represents part of a molecular structure. The end of each straight line signifies a carbon atom which is bonded to its neighbouring carbon atom by either a single (one line) or a double (two lines) bond. Inside you can enjoy (as I did) single estate coffees that can be prepared (if there are 2 or 3 of you) in a Chemex, appropriately enough. As I left Esters, I wandered through a local park where, near the entrance to the park, were two helium balloons caught in a tree. One had deflated, the other floated, dejectedly, just beneath the branches. Such a timely observation! The story of the discovery of helium connects the signboard at Esters, a cup of coffee and helium itself, how could that be? You’ll just have to keep reading to find out.
The colours of “neon signs” depend on the particular gas (eg. neon) in the tubes
Helium is the second most plentiful element in the universe but on earth it is relatively rare. It was therefore not discovered on earth but, instead, by looking at the Sun. Its ‘discovery’ in the Sun was due to the way in which atoms interact with light. The atoms in each element emit (or absorb) light at specific frequencies. These frequencies correspond to different colours. It is this property of atoms that creates colours such as the distinctive hue of neon lights. In 1868 two astronomers were observing the same solar eclipse. Independently of each other, they noticed a distinct emission of light from the Sun at a wavelength of 587.49 nanometres (yellow-ish). This emission line corresponded to no element that had been found on earth and so one of them, Norman Lockyer suggested naming this new element helium, after ‘Helios’ the Greek god of the Sun. Helium was not found on earth for another 27 years when William Ramsay isolated it from a uranium based compound. The gas that Ramsay extracted, absorbed and emitted light at the same frequency as the two astronomers had observed for the element in the Sun. Helium had been found on earth.
Atoms absorb (and emit) light because of the way that the electrons in the atoms are arranged around the atomic nucleus. The electrons exist in discrete energy states that we can imagine as rungs on a ladder. Electrons move between the states by absorbing, or emitting, light at specific energies (corresponding to a step up, or a step down on the ladder). As the energy of light depends on its frequency, the colour of an element depends on the spacing of the rungs of this atomic ladder, which is different for different elements. The energy ladder of helium atoms means that helium emits light at 587.49 nanometres. In organic molecules (ie. all the molecules that make up you and I and coffee), it is often the double carbon bonds that provide the energy ‘step’ in the visible range of light. Depending on the number of carbon atoms that are double bonded and the number in the molecule that are not, the energy step is tweaked slightly so that it will absorb in the red region in some materials and in the blue in others. We have our link between the sign at Esters and the observations of the astronomers.
However the explanation above depends on knowing some properties of electrons in atoms and some details of quantum mechanics. Neither electrons (discovered in 1897) nor quantum mechanics were known to the discoverers of helium. How did the astronomers recognise that their observation of a particular colour of light meant that they had identified a new element? Part of the answer must be based on experience. Experimentalists had already found out that different materials absorbed (and emitted) light at different but specific, frequencies. The other part of the answer brings us to our link with coffee.
A milk ring in water. Once it was thought that atoms might look like this (but a lot smaller).
In the video Coffee Smoke rings, we can make rings of milk travel through coffee or water. These rings are vortices which are closed up on themselves to form a doughnut shape. Mathematically, the vortex ring is a completely stable structure, it never decays. You could argue that the reason that it decays in the video is because we live in a non-ideal world with non-ideal liquids (milk and water). Returning to the mathematical world, each vortex ring will vibrate at specific, (resonance) frequencies dependent on its diameter, just like a bell rings with a note dependent on the size of the bell. So, even without knowing about electrons or quantum mechanics, it becomes conceivable that the atoms that go to make up a substance have specific resonance frequencies. If you imagine that atoms are in fact extremely small vortex rings (of the kind you find in a coffee cup), the model even has a predictive power. In 1867 William Thomson proposed such a “vortex atom” model and suggested that the distinct vibrations of the rings led to energy levels, like the ladders of later quantum mechanics and exactly of the sort that were observed by the astronomers. By considering that a sodium atom was made out of two inter-locked vortex rings, the light emission of sodium could even be accounted for. It was therefore entirely conceivable that elements would have distinct fingerprints as the astronomers had observed for this new element, helium.
We have therefore found the connection between the signboard at Esters, milk rings in a coffee cup and the discovery of helium. You would be forgiven for thinking that part of the connection is purely historical, after all, our current models of the atom do not rely on vortex rings at all. However, there is a relatively new theory called “string theory”. More fundamental than atoms, string theory proposes that there exist ‘strings’ that may be closed on themselves and that have specific vibrations that depend on their size and geometry. Sound familiar? Perhaps the connection with the milk rings lives on.
A few weeks ago, while having lunch with colleagues, one of them was complaining about his problems with his morning tea. So desperate he was to get his cup, he kept tipping the teapot to steeper and steeper angles in an attempt to increase the rate of pouring. Unfortunately, when he did so, the flow out of the spout became chaotic and, rather than having a nice cup of tea, he had a mess on the table. Another colleague suggested (sensibly) that it was a problem with the air-hole at the top of the teapot, not enough air was getting into the pot to enable the tea to flow smoothly out. In fact, my colleague’s tea pot problem turned out to have a different cause that will be featured in the Daily Grind in a few weeks. However, it did get me thinking about the purpose of the air hole in take-away coffee cups.
On the lid of a take-away cup are two holes. One, for drinking from while in a rush to get from A to B, the other, a very small air inlet hole that allows the coffee to flow nicely from the drinking hole. The requirement for such an air inlet has been known for millenia, however it was not understood why it was needed. Traditionally it was explained by saying that “nature abhors a vacuum”, the idea being that the coffee could not leave the cup because if it did so it would leave a vacuum which nature ‘does not allow’.
The lid of a take-away cup has two holes. One for drinking from, the other to let air in.
An immediate problem with such an argument is that it implies that coffee has a will; nature ‘does not want’ a vacuum. Indeed for Rene Descartes (of “I think therefore I am” fame) this was a key problem with the traditional explanation. Descartes died in Stockholm in 1650, although for twenty years before that he had lived in Holland. For Europeans, the Dutch were fairly fast off the mark in terms of the introduction of coffee into their society. They had managed to get hold of a coffee plant in 1616 but only started properly growing coffee for themselves (in Ceylon!) in 1658, a few years after Descartes’ death. It is therefore unlikely that Descartes ever had the opportunity to try much coffee. Instead, when Descartes thought about the importance of air holes, the example that he used was a wine cask. In ‘The World‘, written in about 1632 he states “When the wine in a cask does not flow from the bottom opening because the top is completely closed, it is improper to say, as they ordinarily do, that this takes place through ‘fear of a vacuum’. We are well aware that the wine has no mind to fear anything; and even if it did, I do not know for what reason it could be apprehensive of this vacuum…”
The space behind a swimming fish is immediately filled with water as the fish moves forward.
For Descartes, the reason that an air hole was needed in the wine cask was not because nature hated a vacuum but because, on the contrary, nature was completely ‘full’ of matter. Whether that matter was wine, air or the material that made up the barrel, the world was full of ‘stuff’, meaning that if wine came out of the cask the air that it displaced had to go somewhere. Having nowhere else in the universe to go, this displaced air would have to go into the region of the cask that the wine had just vacated. Descartes compared this movement of air into the top of the cask to the displacement of water by fish as they swam through water. We may not notice the water in front of the fish moving to the back as the fish swims through the water but we know that the water must fill the empty space left by the moving fish. In the same way we do not perceive the air to flow from the outlet of the wine cask to the top of the barrel, but we know that it must (because, Descartes thought, it had nowhere else that it could go).
This explanation had far reaching consequences for Descartes world view. He could explain gravity and the motion of the planets as a consequence of the planets moving in a giant vortex of a substance around the Sun. The image of the solar system as a giant cup of coffee being stirred is one that the Daily Grind is sure to return to at some point. For the moment though, we need to step back and think. We know that the universe is not ‘full’ in the sense meant by Descartes and so this part of his explanation must be wrong, but why is it that blocking the air inlet hole stops the flow of water out of the cup?
Whether coffee leaves the cup or not depends on a balance of forces
Think about the schematic shown here. Gravity is pulling on the mass of coffee in the cup through the drinking hole. Air pressure is acting against this pull, pushing the coffee back into the cup (if you ever wanted a demonstration of how powerful air pressure can be, try sealing an empty water bottle before coming down a mountain or at the start of the descent in a plane). There is also air pressure inside the cup acting downwards on the coffee. With the air hole open, this air pressure is fairly equal to that outside of the cup. The inside air pressure cancels the outside air pressure, gravity wins and the coffee comes out. Imagine now closing the air hole. No air can get into the cup so, after a little coffee leaves, the air pressure inside the cup drops to less than the air pressure outside of the cup. This time, the air pressure outside the cup pushes the coffee back into the cup more than gravity pulls it out and the coffee stays in the cup. Can we test this explanation? One way to test the theory would be to somehow change the pressure inside the cup. Using two identical cups (which I got from the very friendly people with good coffee at Iris and June), the video below shows two experiments. In the first, both cups are filled with the same amount of cold ‘coffee’ (no coffee is ever wasted in these videos, dregs are recycled). The second experiment shows one cup holding cold coffee, one holding steaming coffee. Why might these experiments support the theory that it is air pressure that keeps the coffee in? Perhaps you can think of better experiments, or improvements to this one, let me know in the comments section below, but most of all, enjoy your coffee while you do so.
(note that the cups had got a bit water damaged through practise runs before filming. Note also that for this experiment to be meaningful, you would need to repeat the measurements many times so that you can build up a statistical picture, but that would make the video quite boring).
Last Thursday, I had the opportunity to try the coffee at Brunswick House. The old building which houses this cafe/restaurant sits on the corner of a major junction two minutes walk from Vauxhall tube station and feels somewhat out of place with the buildings around it. Inside, the incongruity continues with quirky decor and bookcases stacked with all manner of titles. Coffee beans are supplied by the roasters Coleman Coffee. As it was a lunchtime, I had a very enjoyable cortado (an espresso “cut” with steamed milk in a ratio of 1:1 – 1:2) which was full of flavour but not too bitter. With friendly staff and a spacious interior, this is definitely a place to return to whenever I am next in the Vauxhall area.
However, The Daily Grind is not so much interested purely in the coffee as in the connections between what we can observe in the coffee cup and the physics of the wider world. At Brunswick House, this came in the form of the link between one way in which we know that space is cold and a seemingly mundane observation, the condensation of water onto cold surfaces. Lifting my glass to appreciate the cortado, I noticed a number of water droplets on the (cold) saucer underneath the (hot) cup. As I kept the cup on the saucer, the saucer became warmer and the water droplets evaporated. By the time I finished my coffee, the saucer was dry. We can observe a similar phenomenon on the inside rim of a cup of steaming hot coffee. As we watch, water droplets form around the cold rim of the cup before starting to evaporate off again as the cup gets warmer. How is this related to the coldness of space? For that, we have to digress to an essay written two hundred years ago about dew.
The cortado on the saucer.
William Charles Wells published his “Essay on Dew” in 1814 after two years of patient observation of the circumstances under which dew formed in the mornings. By carefully noting the weather conditions of the night preceding the dew fall and the surfaces onto which the dew formed, Wells came to some important conclusions. Firstly, the surfaces onto which dew formed suggested that the earth must be radiating heat into space; space must be cold. Secondly, the earth lost more heat on some nights than on others, it appeared that certain clouds kept the surface of the earth warm. If Wells was right it suggests that there is a natural greenhouse effect which is helpful for life on earth. This in turn suggests that the surface temperature of the earth is the result of a delicate balance between heat transfer to and away from our planet. Upsetting this balance (by introducing more greenhouse gases for example), could have serious consequences. Was Wells right? Perhaps we should start noticing when and where dew forms. So, over the next few weeks, make a note of dew laden mornings. Where did the dew form and under what circumstances? Do you agree with Wells? Let me know in the comments section (below). In a few weeks we will revisit Wells and his essay, in the meanwhile, enjoy your coffee!
The world of scientific research is supported by a vast volunteer network. Yes, scientists get paid to research their subject but in order to let the wider community know about their results, they have to publish it. To filter out the good papers from the bad or mediocre, working scientists volunteer to review papers submitted for publication. Each ‘reviewing’ scientist is anonymous to the authors of the paper, though the authors are not (yet?) anonymous to the reviewers.
At its best, the scientists reviewing the paper help the authors of the submitted manuscript to refine their papers, suggesting thoughts, other experiments or methods of phrasing that may better capture what the authors had intended. The review process is not just essential for filtering the good from the bad, it is extremely helpful for working scientists to have the input of someone, not involved with their research, commenting on it and trying to improve it. Although it is far from perfect, the review process is indispensable.
Which brings me onto Bean thinking. As a working scientist, I have got very used to the benefits that ‘peer’ review can bring. Therefore, over the past month, I asked 8 physicists and 8 non-physicists to review Bean thinking. These sixteen people were asked to critically read Bean thinking and let me know what they think. Unlike the scientific review process, it wasn’t anonymous, I knew who they were. But I also chose them because I respected each of their opinions and thought that each of these sixteen people would truly tell me what they thought. In this way, I hoped that Bean thinking could be refined to make it more engaging and entertaining while remaining scientifically rigorous. These sixteen got nothing tangible in return for their help which is why they are getting a mention on this page.
You know who you are, I know who you are. I am very grateful to all of you who took the time to read over and comment on Bean thinking. I have tried to take on board as many of your comments as possible (note the number of new photos on the pages!). Obviously, there are some comments that I haven’t been able to incorporate and any errors in the science (of which I hope there aren’t many) remain mine. Nonetheless, I am very grateful to you sixteen (and a few others who came in along the way). I hope you continue to visit Bean thinking, let me know what you think and join the discussion. And to all visitors, please leave any thoughts about the new look Bean thinking including any ideas for experiments that could be included in “Coffee cup science” in the comments section below.
As this is the first true blog post, let’s do the introductions. What is Bean thinking and who is @thinking_bean?
The human bean behind @thinking_bean has worked for a fair few years in university research centres, researching obscure but fascinating areas of physics where magnetism meets superconductivity. Such research fields can be very beautiful but perhaps not of immediate technological relevance. Understandably, this can cause some in our society to question the utility of investigating these phenomena. Part of the motivation behind Bean thinking is to explore this question, why do we do science?
A second motivation is to share the wonder of the world that today’s understanding of physics gives us. Some of these beautiful areas have not yet been fully understood even though they occur in something as apparently simple as a coffee cup. Through teaching, outreach, talking to friends and even in conversations with some colleagues, I became aware of the way that science, perhaps particularly physics, can be perceived as a very interesting, but perhaps very difficult subject, far removed from people’s everyday lives.
Yet this is not true! Slow down, put down your smart phone, e-book or tablet, observe the world. Physics is all around you. Warming your hands around a mug of hot coffee, you may not realise how it is related to the Big Bang. Looking at a glass of milk can illustrate the reasons that the sky is blue. Even the mere act of stirring coffee can be related the Heathrow minute (link, link2).
Hence Bean thinking, which hopefully will become a space where curious individuals can come and discuss interesting phenomena that they notice in the day to day. If this can be done with a cup of coffee, all the better. The point is to slow down and start noticing. Each Wednesday I will update the Bean thinking blog, the “Daily Grind” with things that I have noticed or that I find interesting. Who knows, if anyone starts to read this and shares their observations perhaps the Daily Grind can also include these. As this website develops, I may add a forum, but for the moment, please let me know what you think about the concept and what you observe around you in the comments section below.
