Science
 | How to see the invisible infrared world using your mobile phone camera Using your mobile phone, you can see infrared radiation – a normally invisible part of the electromagnetic spectrum. Ken’s Tech Tips looks at some of the physics of electromagnetic waves and explains how you can see this invisible world – and you don’t need anything more than the mobile phone in your pocket. What is infrared radiation? Infrared is a form of electromagnetic radiation. Other forms of electromagnetic radiation (EM radiation) include visible light, x-rays, microwaves (the EM waves that wi-fi networks use and also the waves that cook your food in microwave ovens) and radio waves. The difference between all these different forms of radiation are the wavelength of the EM wave. We can illustrate this electromagnetic spectrum (CC-licensed image from Wikipedia):
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| Facebook leads to lower grades!?!
In what must be one of the most ridiculously alarmist and inaccurate articles I’ve read in a while, career website Milkround is claiming that Facebook users could risk having lower grades as a result of their usage of the social networking site. Unfortunately, it looks like another instance of a journalist falling for the “correlation implies causation” fallacy. According to Milkround:
By implication of the article and study, a typical student would do 4 times more work if they didn’t have Facebook and on average would achieve one grade higher.
Here’s an explanation which is much more likely: More extroverted people who go to more parties and get involved in more societies are much more likely to use Facebook. The people who constantly work 24/7 are the people who are more likely to refuse to get a Facebook account or will have little use for a Facebook account. The likelihood of a student having a Facebook account depends on his participation in college life and how hard working he is. Of course, students do use Facebook as a procrastination tool – I won’t argue with that. But correlations prove nothing. As a more rigiourous technique to test this hypothesis, we’d need to compare student’s results before they signed up to Facebook and results after signing up to Facebook (assuming a constant level of how hard-working or social the students are). Alternatively, you’d need a control group of people who are social and roughly as hard-working as the Facebook group but don’t use Facebook (good luck finding one). | |
| Getting an informed, balanced political debate about science What can be done to ensure an informed and balanced public and political debate of Science and Technology?
The Oxford English Dictionary describes science as “…the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.”1 But science is much more than that: most scientists enter the profession, and most scientific research is funded, because they believe science can greatly improve society. Usually, these goals of learning more about the world and improving society are coupled. However, new and cutting-edge research has been raising ever-increasing concerns about whether the research is benefitting or destroying society. Scientists occasionally argue that their work should be judged on a purely scientific basis without consideration for the ethics and consequences of the research; but this neglects science’s responsibility to the community at large. As issues that affect all of us, it is important that a public debate is held about these topics and that scientists properly engage in it. I believe there are three main barriers to a reasoned public debate. Emotional responses blinding a scientific debate In recent years, there has been an exponential increase in the number of scientific controversies involving ethical issues of “playing God”. These include stem cell research, cloning and genetically modified “Frankenstein” foods. For many people, the initial emotional response is that of disgust2 – something dubbed the “yuk response”. In order to have the more productive debate about the science, consequences and ethics behind the work, we must get past this initial emotional response.
In one study, psychologist Philip Tetlock asked people to comment on the proposal to set up regulated markets to trade organs3. For most people, the response was that of moral outrage at treating sacred body parts as secular commodities to be traded. However, when the debate was reframed to neutralise the moral outrage (e.g. by exploring how organ trading would lead to a greater number of scarce organs being available to save more sacred lives), 40% of people toned down their opposition. Neutralising the moral outrage encouraged people to critically analyse the arguments in the debate and come to a more reasoned decision. On many scientific issues, the “yuk response” is preventing a reasoned scientific debate from happening in the first place. As scientists, we should not ignore our moral guidance, but we must not allow the debate to be blinded by it. Ensuring the media covers the debate accurately The media plays an important role in informing society about issues which may affect them7. However, two factors lead to poor and inaccurate coverage of scientific issues: 1. To maximise readership, the press likes to present scientific issues as a series of horror stories. We’re told that cloning will lead to designer armies of obedient soldiers and that nanotechnology-robots will turn the entire world into a blob of “grey goo”45. These poignant scenarios lead people to make their mind up before considering the scientific uncertainties, risks and benefits to the detriment of a good debate. 2. To provide “balanced” coverage, journalists will try to cover both sides of the story. In a political or social dispute, such as whether the UK should join the Euro, it is reasonable that both sides should be treated equally and receive equal press coverage. However, it is inappropriate to treat the arguments of both sides in a “scientific-fact” controversy as equal. For example, the weight of evidence in favour of climate change is much greater than that against. Attempts by journalists to be “balanced” and present both sides equally give an inaccurate impression that there is still a great deal of scientific controversy about climate change6.
Scientists should be aware of the importance of the media in shaping debate and public opinions and that communicating the science can be as important as the science itself. Engaging the people: Capturing the popular imagination Because of cultural differences8 between science and art (e.g. science being concerned with truth; art about opinions), scientists tend to avoid the arts. However, given debate is all about opinions, scientists should not be afraid to utilise the arts to catalyse debate about issues of scientific importance. For example, Dan Brown’s book “The Da Vinci Code” inspired a large amount of “real world” interest, television documentaries9 and archaeological research about the Holy Grail in Christian theology. In the same way, the arts can provoke discussion about important scientific issues10. The arts will, of course, never replace the rigour of peer-reviewed papers and the scientific process; but as a complement can outline the major issues to the public in an interesting and engaging way without undermining the practice of science itself. Conclusions As science affects the whole of society, scientists have a moral obligation to inform, involve and engage the public in a debate about science. This should be achieved by focusing the debate on the important issues, ensuring they are portrayed accurately and inspiring discussion about them. References 1. Concise Oxford English Dictionary: Science 2. New Scientist: Immoral advances: Is science out of control? 3. Trends in Cognitive Sciences: Thinking the unthinkable: sacred values and taboo cognitions 4. The Guardian: Brave new world or miniature menace? Why Charles fears grey goo nightmare 5. Institute of Physics Press Release: ‘Grey goo’ misconceptions could harm poor in developing world 6. The Independent: Reporters feel the heat over climate change 7. Public Opinion Quarterly: The Agenda-Setting Role of the Mass Media in the Shaping of Public Opinion 8. The University Blog: Science vs. Art 9. Priory-of-sion.com: Da Vinci Code Documentaries 10. The Guardian: ‘Space flight can be as luminous as any novel’ Notes This essay was originally prepared for an essay writing competition at my college. I have decided to share it here as I feel it could be of interest to regular readers. Comments and thoughts very welcome. | |
| “Carbon cost” of Google search same as boiling a kettle
The BBC reports today on a study by Harvard physicist Alex Wissner-Gross. Wissner-Gross claims that performing a standard Google search on a desktop computer produces 7g of CO2. A quick session with two searches will produce 14g of CO2 – the same as that from boiling a kettle. From the BBC article:
According to Google Web History, I’ve performed 9,308 Google searches and it’s only counted the searches I’ve performed whilst I was logged on. I’m guesstimating I perform about 40 searches a day; that’s 15,000 Google searches per year (sounds scary when you put it like that). My annual Google carbon footprint would be 105kg of CO2 (0.15 tons). Google have disputed this figure; saying that a search only produces 0.2g of CO2. I’m not able to comment on what I think of the methodoly as I don’t know how either figure was reached. But I think it is important to point out the difference between average cost and fixed cost. As an example, imagine a server farm which was responsible for 100g of CO2 emissions every day. If ten people perform searches, the average carbon cost of a search is 100g divided by 10 searches = 10g of CO2 per search. This is the average cost of the search.
Whereas, the marginal cost would be the CO2 cost of performing one more search. If we then performed an 11th search, the CO2 emissions of the server farm stay the same (we assume it’s running with spare capacity). The marginal cost of performing a search of zero grams of CO2. With eleven searches, you could claim each search had a carbon cost of 9g. But that’s a bit unfair – considering the CO2 output of the server farm if you had made the search and if you had not, you find the CO2 output it exactly the same. Your search had a marginal cost of zero grams of carbon. Whether Wissner-Gross and Google stated the average cost or the marginal cost I don’t know (although I suspect the first may have been the average cost and the second the marginal cost). With Google’s server farms, we know that they will be running regardless of whether we perform searches or not. The important thing then is the marginal cost of a search – this being so close to zero, I don’t think any of us should feel a guilty conscience from using Google. | |
| Evolving the Mona Lisa by natural selection Fantastic experiment and write up by Roger Alsing. Using an evolutionary algorithm, Roger wrote a programme that would attempt to paint the Mona Lisa using 50 transparent polygons. The “fitness” of each permutation was tested by comparing it pixel by pixel to the actual Mona Lisa. Wonderful. Richard Dawkin’s “The Blind Watchmaker” is a fantastic book to read if you’re interested in evolution. I read it fairly recently; he writes a computer programme to simulate evolution and the results are fantastic. Worth a read. | |
| Predicting the future popularity of a web page
New Scientist reports this week that a new tool developed at HP Labs could potentially predict the popularity of a web page in 30 days time. Essentially they say that by looking at the rate at which a web page picks up views in the first few days can predict the subsequent popularity of the page 90% of the time. It doesn’t seem too radical an idea – after all the pages which are more popular in the first few days are likely to get bookmarked more, linked to more, higher place on Google, etc. The research focused around the sites Digg and YouTube so it would be interesting to see how it could be applied to other sites. You can download the paper online at arXiv.org. On a similar note, I’ve found that I’ve been able to get some incredibly stunning useful information from the popularity of webpages on my site. For example, one of my posts about MSN Messenger downtime gets a lot of hits whenever MSN Messenger goes down. When the number of visitors for that page is significantly above normal, I know that MSN is actually down. If the number of visitors is normal, it’s typically just an issue with my connection or my local server. In fact, I’ve found this method much more reliable than using Microsoft’s own service status page for the Messenger service. Similarly, I found a huge spike in the number of visitors to my post on the possibility of VAT cuts straight after the recent pre-budget report. If only there was a way of exposing these statistics in a useful way! | |
| Could Free Starbucks Win the Election for Obama?
The day of the US presidential election is approaching. There is an expected turnout of 80%. Both parties have worked very hard to register as many new voters as possible and companies such as MTV and Starbucks have been encouraging people to register to vote. Starbucks is offering a free cup of coffee to those who vote on November 4th. How could this distort the results of the election? Well, It seems pretty logical that the people who feel strongly about whether they are Republican or Democrat or have a strong preference for either Obama or McCain are the people who would vote anyway, regardless of incentives such as free coffee. So this promotion probably wouldn’t affect whether they would vote. Swing and undecided voters, on the other hand, may not vote without an additional incentive such as free coffee. If, say, undecided voters mostly lean towards Obama – the incentive of free coffee at Starbucks would benefit Obama in the polls by encouraging the undecided voters to go to the polling station and to vote for him.
It would certainly be an interesting research to see whether this promotion or other incentives may distort the results of the election. The “Starbucks Stores per Capita” differs immensely between each of the states. The District of Columbia for example has 1.18 Starbucks for every 10,000 people – nearly 22 times as many Starbucks stores per capita to Arkansas which has 0.054 Starbucks for 10,000 people. Swing state Virginia has the 11th highest “Starbucks per Capita” of the states. If the Starbucks promotion does have an effect on swing voter turnout, we would expect the biggest effects to be in a) the states with the highest concentration of Starbucks and b) cities (which are of course more liberal than small town America) where people are more likely to have a Starbucks nearby. I’m exaggerating the effects of a free cup of coffee on the election results you say. Perhaps so. But research has shown it can be quite easy to “prime” people to affect who and what they vote for. For example, research found that people who used a church as their local polling station were less supportive of gay marriage. Another piece of research looked at a 2000 ballot initiative in Arizona to increase spending on education:
And when I spoke to some local activists for the Labour Party (UK) earlier this year, they suggested that the Gordon Brown calls an election before 2009. Not because they believe he is more likely to win: they believe that Gordon Brown losing the next general election is already a done deal. It’s because the local elections are also due to be held in 2009. And having the general election at the same time as the local one would mean Brown’s personal unpopularity would rub off onto the rest of the Labour party and their local councillors. There are many subtle ways of affecting the results of an election. Could free Starbucks have a significant one? | |
| The Six Degrees of Separation – Now Just Three
Some fascinating research by mobile communications company O2 found that the six degrees of separation (the theory everyone in the world can be linked in six steps) have fallen to just three due to modern telecommunications and social networking. However, instead of simply looking at the networks of friends, family and work, O2′s study also considers shared interest networks.
According to O2, email and mobile phones had the most significant impact in reducing the degrees of separation to three.
Great research. I must admit I’ve been astounded by some connections I’ve discovered over the last year or two. My summer job boss happened to be one of my physics tutor’s PHD supervisors. My previous boss was the PHD supervisor of one of my physics teachers when they were at university a hundred miles away. My previous boss was also working with one of my university astronomy lecturers. A flatmate of one of my best friends at university (about 250 miles away) happens to be a friend of mine and they certainly didn’t meet each another through me!. Thinking about my own networks – having met many politicians including Boris Johnson, I’m no more than two steps away from Tony Blair, Gordon Brown, the Queen and so on. I certainly have Vladimir Putin, George Bush and Sarkozy in my three degrees of separation. Celebrity wise: I’m no more than two degrees of separation from Kylie Minogue, Tim Henman, Hayden Panettiere, Emma Watson, David Tennant… again, it’s quite concievable that a large number of actors and celebrities are within my three degrees. Pretty amazing. | |
| The Large Hadron Collider and the End of the World?
It’s been rather, well, amusing to see the news coverage of the test firing of the Large Hadron Collider over the large few days. As somebody who has worked in physics and may occasionally classify themselves as a “physicist”, it’s really nice to see physics making the headlines! But I thought the news coverage was absolutely sensationalist and ridiculous. The downmarket British tabloid The Sun was ridiculously sensationalist with it’s headline “End of the world due in nine days”. It wrote:
It wasn’t just the downmarket tabloids at it. BBC News discussed the outlandish theory, and ITV originally reported the story as so on their website:
And I woke up in the morning to a long discussion on the radio about the LHC would cause the end of the world. I’m sorry, but as if any serious scientists thought the LHC would lead to the end of the world. It’s a totally ridiculous theory. But I’m more than happy to be proved wrong. Check out the live webcams from the LHC and let me know if you see anything | |
| How Distributed Grid Computing Could Cut Costs and Help the Environment
The dream of distributed computing (or grid computing) is that it can cut the costs of computing and cut carbon emissions. In this post, I am to explain how it works. Let us imagine a scenario where both Carl and Daniel have computers. Carl has a computer which is twice as efficient – that is it costs him half as much to do the same thing on his computer. Let’s say it costs £1 in electricity for Carl to run a computer model; and £2 for Daniel. In total, it costs £3 to society to run the computer model once for Carl and once for Daniel. Cost to Carl: £1 With Distributed Computing Now imagine the same scenario but with one addition: distributed computing. As it costs Carl less money to run the model on his computer than it would cost Daniel, Daniel could pay Carl to run the model for him. Imagine that Daniel paid Carl £1.50. It only costs Carl £1 to run the model Daniel’s model for him, but he has gained £1.50 for his effort giving him a profit of 50p. Daniel only spends £1.50 to have his model run, as opposed to the £2 which it would have cost him to run the model himself. Everybody benefits by saving money and the end result is the same: Carl and Daniel have both had their model run. Cost to Carl: 50p (£1 to run his own model, subtract 50p profit from running Daniel’s model) What assumptions have we made?
There are no costs involved in the transaction itself. Imagine that it costs £2 for Daniel to send a copy of the computer model to Carl and then to receive the results. If Daniel had to print out instructions on how to use the model, then FedEx it to Carl and wait several weeks to see the results of the model, that’s perfectly conceivable. In this case, it costs of Daniel asking Carl to run the model for him would be £3 (£1 for Carl to run the model on his computer and £2 in transaction costs). In this case, he might as well have run it himself. Real world transaction costs would include slow network connections and incompatibilities between different computer systems. So for distributed computing to work we need fast, reliable network connections and software compatibility. Daniel would happily allow Carl to run the model for him. Are there privacy implications for example? Daniel must be confident that he can allow Carl to run the model for him and be equally confident that Carl couldn’t have a peek at the results of his model. After all, there might be trade secrets in there. Similarly, Carl must be confident that Daniel isn’t sending him malicious software which could break his computer. For distributed computing to work, there must be a foolproof and hackproof way for Carl and Daniel to trust each another to keep to their side of the bargain.
Thirdly, Daniel must actually be able to cut his costs. Let me explain. It’s possible that Daniel will have his computer on 24/7 anyway. That is, it’ll cost him £2 whether he’s runs the model or not. If he’s leaving his computer running at 100% but idle and still asks Carl to run the model for him, he essentially pays for the model to be run twice. My computer doesn’t dynamically underclock so whether or not I’m using it, it’s eating up the same amount of energy. For distributed computing to work, our own computers must make much more efficient use of resources. We need to have thin-client computers with neglible costs. The real world Distributed computing hasn’t taken off yet on any large scale. The three conditions don’t yet exist:
It’s already being used… Last year I worked at a company which employed distributed computing on a smaller scale. They had a small cluster (~20 computers) with identical hardware, each linked with Gigabit Ethernet. Software ran inside virtual machines and those virtual machines moved around between computers depending on the amount of spare capacity each one had. The reason why they could employ distributed computing is because within their own system, they knew that:
Distributed and grid computing isn’t yet practical on a worldwide scale but I think we’re making progress. Networks are becoming more reliable. Software platforms appear to be becoming more standardised. Virtual machines are coming of age. And our computers are becoming more environmentally concious and adapting their resource usage to the amount of processing power required. So there is the blueprint to how we can lower the costs of computing. You might be wondering what that’s got to do with the environment. Well, simply replace the £ sign with Joules of energy. Like free-market trade can leads to an efficient allocation of resources in the real world, the trade of computer time in a distributed grid of computers leads to a more efficient allocation of computing resources. And that lowers the energy consumption of computing and it’s environmental impact. |
