Archive for the ‘Physics’ Category


Post A Comment »Posted on Wednesday 31 December, 2008 at 11:59 pm by Jacob Aron
In Physics, Space & Astronomy

As another year draws to a close, you’ve got just 61 seconds left of 2008. That’s right, 61. This year, official timekeepers are adding a “leap second” on to the end of the last minute of the last hour of 2008. You might not notice the extra second flit past as you Auld Lang Syne your way in to 2009, but it serves an important purpose.

Our measurement of time used to be based on the movement of the Sun; you got up when it rose and went to bed when it set. Advances in technology meant that timepieces had to become more and more accurate. It starting with the need for coordinated train timetables across a country, meaning that local time just didn’t cut it any more. In the mid-19th century, railway companies around Great Britain adopted Greenwich Mean Time, the familiar GMT. Use by all soon followed.

GMT was still based on the movement of the Sun however, and this is where we hit a problem. The Sun, of course, does not actually move across the sky; it only appears to because the Earth is rotating. The Earth’s rotation is not constant though; changes in the atmosphere or the planet’s molten core can cause it to speed up and slow down.

With the introduction of technology such as GPS positioning and the internet, even more accurate time was needed. Physicists found that oscillation of caesium atoms could be used to define a second; and in 1967 the International System of Units (SI) decreed the duration of 9,192,631,770 such oscillations to be exactly one second.

These so-called atomic clocks are now the de facto standard of time, known as Coordinated Universal Time (UTC). The trouble is, this highly accurate measure doesn’t have any connection to the Earth’s rotation, so if we still want noon to occur when the Sun is at its highest point, corrections to UTC must occasionally be made. Enter the leap second.

Without the occasional leap second (the last was three years ago) UTC would gradually drift away from what we might perceive was “real” time. Eventually, the position of the Sun would have no relation at all to the time, and we can’t be having that. Earlier this year, some scientists proposed that rather than adding a leap second every few years, we should add a leap hour every 6 centuries. This doesn’t sound like the best idea to me - adding a few seconds here and there is easy to slip past people with out too much fuss, but an entire hour? No thanks.

What would we even call such an hour? For those of you with timepieces connected to an atomic clock (like this one, perhaps) might notice the strange occurrence of 23:59:60 before it flicks over to 00:00:00 and the new year. Would a leap hour run from 24:00:00 to 24:59:59? Surely it would cause nothing but problems.

No, a leap second seems to be the way to go. Even though you’re probably not reading this at 11:59pm (and let’s be honest, the sever is posting it at this time, not me!), join me in the rather unusual New Years countdown of 5, 4, 3, 2, 1, 1…

Post A Comment »Posted on Tuesday 30 December, 2008 at 5:20 pm by Jacob Aron
In Inventions & Technology, Physics

Last night I watch the first of this year’s annual Christmas Lectures from the Royal Institution. The lectures, first given by Michael Faraday in 1825, are designed to educate and entertain children with science.

This year the overarching topic for the lectures was “The Quest for the Ultimate Computer”, and they were given by Professor Christopher Bishop who works at both Microsoft and the University of Edinburgh. This first lecture was entitled “Breaking the speed limit”, and covered the evolution of the microprocessor, the building block of all computers.

The ever-increasing power of computers is all down to Moore’s law. In 1965 the founder of computing giant Intel, Gordon E. Moore, noticed that the number of transistors that can be placed on a computer chip doubles roughly every two years. Amazingly, this means that computers made two years from now will have as much processing power as every computer ever made in the past.

Prof. Bishop used his first lecture to explain exactly what a transistor is - something that I had never had an easy-to-understand explanation for. A transistor is basically an electronic switch that also uses electric current to turn on and off - in other words, no moving parts. This makes them perfect for the construction of logic gates, the very simplest possible computational element. Logic gates come in many forms, but all of these can be built from transistors.

In a number of practical demonstrations, the audience is shown how chips are be manufactured; it’s a rather clever technique. Since the circuitry of a chip is so small and complex, they are actually designed on a much larger scale and then projected on a screen. Light from this screen is shrunk down by a lens on to a light-sensitive material, which marks out the exact design in miniature.

The “speed limit” that Prof. Bishop talks about is actually a physical limit - we simply can’t squeeze any more transistors on to one chip. The solution at the moment is to include many chips in one computer - most PC’s sold these days are marketed as “dual-” or “quad-core”. Not all tasks can be sped up by splitting the workload however; as Prof. Bishop tells us, it takes a woman nine months to make a baby, but nine women can’t make a baby in one month!

If we can’t figure out a way to make better transistors, computers won’t be able to get any faster, as they will just get too hot. This is comically illustrated by making all the children stand up and sit down as fast as they can. If we continue with current technology, in 10 years time chips would be as hot as the surface of the sun. Not something you want in your laptop!

A future solution could be to use carbon nanotubes, which would produce a transistor capable of switching 1,000 times faster than our current silicon models. We could even one day be using DNA to do our computations, though Prof. Bishop admits this is very far off. It sounds like a neat idea however, as the DNA of just one human being can store more information than all of the computers in the world put together.

If you’re as interested as I am to learn about the future of computing, you can watch the remainder of the Christmas Lectures every day this week on Channel Five at 7.15pm. Tonight’s lecture promises “Chips with everything”, so tune in and find out more!

Post A Comment »Posted on Friday 26 December, 2008 at 1:08 pm by Jacob Aron
In Getting It Wrong, Physics

As part of the Guardian’s Cif charades series, “Cif regulars write about a counterintuitive topic suggested by our readers”, Michele Hanson has shared with us her thoughts on quantum physics. Hint: I’m not very impressed.

Hanson believes that physicists aren’t “choosing their projects wisely”, and are “aiming a little too high” with their research into the quantum world. After all, what use is quantum physics? It’s not like it helps us understand semiconductors, vital in the construction of many electronics, or build MRI scanners, which help millions of people around the world. No, wait - yes it does. Just because Niels Bohr worked on the Manhattan Project, it doesn’t mean we should throw all of his research out of the window.

She aks “How can you not know how something worked if you’ve just worked out how it worked, and made it work?” I had to re-read the sentence a couple of times just to understand the question. Here’s the problem: quantum physics is weird. Like much of science, the results are counter-intuitive, difficult to understand, and an incomplete model of how the world truly is. Guess what though? Science works, bitches.

Still, because Hanson can’t get her “fluffy little head around” it, quantum physics isn’t important. Speaking to a friend, she discovers they share a basic knowledge of physics, up to a point:

..I asked another friend out with her dog. Her knowledge of plain, never mind quantum, physics was fairly basic. “Apples fall on your head,” she said. “Heat rises except in my oven, and E = mc².”

I can manage that, except for the last equation. Let’s not go there.

Oh no, an equation! We musn’t let anyone see the dreaded equals sign, lest they be overcome by it’s damning parallel lines. Begone, foul beast! At least I can take comfort in most of the Cif commenters disagreeing with Hanson as well. After all, this is a woman who believes that girls shouldn’t be encouraged in the sciences because “girls in general just aren’t that keen on science.” Bleurgh.

Post A Comment »Posted on Saturday 13 December, 2008 at 3:47 pm by Jacob Aron
In Biology, Education, Inventions & Technology, Physics, Space & Astronomy

TIME magazine, as part of their “Top 10 Everything of 2008″ series have released the ten most impressive scientific discoveries of the year. “Discoveries” might be stretching it a bit for some of the entries - accomplishments, perhaps? Semantics aside, let’s have a look at the list:

1. Large Hadron Collider

No surprises here. The LHC was the biggest thing in science for most of the year, with extensive coverage in the mainstream media. Even here at Just A Theory I’ve written quite a bit on everyone’s favourite particle accelerator. Unfortunately, there won’t be any discoveries made at CERN for a while yet - a helium leak soon after it was started means the collider won’t be up and running again until sometime next June.

2. The North Pole of Mars

Well, we already knew it was there, but this year in May NASA’s Phoenix probe landed in Mar’s far northern region. No signs of life were found, but we now have further confirmation that Mars was once a wet planet, much like our own Earth.

3. Creating Life

Geneticist J. Craig Venter, instrumental in mapping the human genome, wrote the genetic code for an entirely new type of bacterium, Mycoplasma laboratorium. He and his team put together 582,000 base pairs that make up the genetic information of the new species. Next, this DNA must be inserted into a living bacterium to see if it can take over, effectively creating artificial life.

4. China Soars into Space

The world’s biggest country made new strides into space this year, with the first Chinese spacewalk spacewalk. Pretty impressive, since it’s only their third mission in a space programme that began in 2003.

5. More Gorillas in the Mist

For once, some good news on animal conservation. It turns out that previous estimates of the number of western lowland gorillas were too low, and the Republic of Congo is now thought to contain 125,000 gorillas - twice as many as previously thought.

6. Brave New Worlds

The discovery of extrasolar solar planets continued at a rapid pace this year, with 45 new worlds announced in June by Swiss astronomer Michel Mayor. Later on in November, we got the first ever pictures of planets around another star thank’s to good ol’ Hubble.

7. The Power of Invisibility

Scientists at Berkeley, University of California, announced the invention of an invisibility cloak. Nanotechnology and metamaterials make it possible for an object to completely vanish, but don’t expect your own cloak soon - it’s far from ready to be practical yet.

8. Cenozoic Park?

In Novemeber, biochemistry professor Steven Schuster of Penn State University revealed 80% of the genome of the ancient woolly mammoth, painstakingly recovered using fossilised hair. This lead to speculation we might one day be cloning the furry creatures - has no one seen Jurassic Park?!

9. Can You Spell Science?

Between 1979 and 2006, the percentage of science literacy in adults has doubled to 17%. It’s not that great news though - according to the survey by the University of Michigan, a quarter of the US population count as “civic scientifically literate”. In other words, three in four adults will struggle to understand science stories printed in the media - I wonder if that includes this blog?!

10. First Family

Finally, we have the discovery of the first “nuclear family”. In Saxony-Anhalt in central Germany, a 4,600-year-old grave was discovered to contain the remains of an adult male and female, and two boys aged 8 to 9 and 4 to 5. DNA evidence confirmed their relationships: they are indeed the First Family.

2 Comments »Posted on Sunday 7 December, 2008 at 4:04 pm by Jacob Aron
In Biology, Education, Physics, Weekly Roundup

Shell I never

A photo from the Boer War has revealed that a tortoise named Jonathan is one of the world’s oldest living animals, at age 176.

Jonathan in 1900, aged around 70, on the island of St Helena

It’s crazy to think that this tortoise was born in 1832. The same year saw the birth of Lewis Carroll (author of Alice in Wonderland) and the death of the mathematician Évariste Galois, whose pioneering work in group theory ended when he was killed in a duel. Of course, Jonathan has no connection to this events, but still - he’s pretty damn old.

LHC still broken, but not broke

Poor Large Hadron Collider. You just don’t seem to be able to catch a break. It seems that when the particle accelerator leaked helium earlier in the year, the damage was quite extensive. Repair costs will be almost £14m, and the LHC won’t be ready to turn back on until next summer.

Now, £14m isn’t much compared to the £4.4 billion it cost to build in the first place (yes, £4.4 billion, not million as The Telegraph is reporting…) but it’s still a fair chunk of change. LHC haters shouldn’t have to worry about the begging bowl being passed their way however, as CERN hope to meet the costs within their existing budget.

£250m for training new scientists

The Engineering and Physical Sciences Research Council (EPSRC), the UK’s funding body for science and engineering, has pledged £250m to invest in training the scientists and engineers of the future.

The money will allow the creation of 44 training centres across the country, and give funding to more then 2,000 PhD students. Lord Drayson, the Minister for Science and Innovation, was enthusiastic about the centres:

“Britain faces many challenges in the 21st Century and needs scientists and engineers with the right skills to find answers to these challenges, build a strong economy and keep us globally competitive,” he said.

“This is an exciting, innovative approach to training young researchers and will help build a better future for Britain.”

It’s nice to see that even in these times of economic woe, scientists aren’t being forgotten!

Post A Comment »Posted on Monday 1 December, 2008 at 8:11 am by Jacob Aron
In Biology, Chemistry, Physics

A couple of months ago I wondered whether we were seeing a new development in science communication; namely scientific rapping. First there was the Large Hadron Collider Rap, which was then followed by the Astrobiology Rap. Alas, it seems that no further offerings have emerged.

All is not lost, however, as it seems we have a new form of communication: dance. A while ago, the journal Science put out a call for scientists around the world to share their Ph.D research in the form of interpretive dance - an unusual request, I grant you, but one that has resulted in some interesting compositions.

Prizes were awarded in four categories: Graduate Students, Postdocs, Professors, and Popular Choice. I’ve embedded the videos for you below; see what you make of them and then click through to the article to find out what they’re all about. Warning: I may have purposely miss-categorised this post to confuse you!

Graduate Students

Postdocs

Professors

Popular Choice

Post A Comment »Posted on Tuesday 25 November, 2008 at 11:52 am by Jacob Aron
In Just A Review, Physics

Einstein is one of the most famous scientists who ever lived. You may not know the meaning of E = mc2, but you’ve certainly heard about it. Eddington on the other hand - who is he? Even I can only name one of Eddington’s achievements; namely the 1919 expedition to the South African island of Principe to observe a solar eclipse. It was here that Einstein’s Theory of General Relativity was put to the test, and it is here that the BBC drama Einstein and Eddington begins.

As Eddington awaits the eclipse, hoping for the rain to end, we flashback to five years earlier. The First World War is beginning, and the conflict between England and Germany has spilled over into science. Germany is rounding up its experts in preparation for war, and there is one man they desperately want: Einstein. Eddington is tasked with finding out why.

Einstein and Eddington is a treat for fans of science fiction as much as fans of science. Andy Serkis (Gollum from Lord of the Rings) and David Tennant (Doctor Who) take the titular roles and make them their own. Writer Paul Moffat takes every opportunity to contrast the two men, and Serkis’s crazy-haired womanising Einstein is a far cry from the homosexually repressed Quaker Eddington, who makes a welcome change from Tennant’s typically manic Tardis dweller.

At times, this was perhaps taken a little too far - although I admit to not being widely read on Eddington, I’ve literally never seen any mention of him being gay. It might be that this aspect of his personality was accentuated a little to further stand apart from Einstein.

This could be because their differences were essential to the message of the film: science transcends all. Eddington, railing against a proposal to banish all German members from the Royal Observatory following the gas attack at Ypres cries “The pursuit of truth in science transcends national boundries, takes us beyond hatred, and anger and fear! It is the best of us!” Einstein is equally horrified by what his countrymen in Berlin have done, and his outbursts lead to him being denied access to the University.

These two men, so different in their approach both to science (Einstein was a theorist, whilst Eddington prided himself on being “the best measuring man in England) and to life, brought about a scientific revolution and overthrew Newton despite only corresponding by letter. Indeed, our protagonists don’t even meet in the film until one, final, handshake.

It’s undoubtedly great drama, but is it great science communication? As is perhaps unavoidable, much of the science is conveyed outside of the drama. Einstein explains his ideas to his son, and Eddington turns to a convenient German family which he rescues from beatings at the hands of the English. The concepts are there, including a nice demonstration of the curvature of space using a tablecloth, a loaf of bread and an apple, but it can’t help but feel slightly off. Still, the ideas are presented as interesting enough for the casual viewer to pursue if they wish. Disputes about the accuracy of Eddington’s confirmation in Africa are also swiftly brushed under the table - but that’s only to be expected, as they don’t fit into the tidy narrative.

If I sound a little down on the film, I’m not. I really enjoyed it, and the forthcoming DVD release has already been added to my Christmas wishlist. If you don’t want to wait that long, you can watch on BBC iPlayer until this Saturday evening. Even if you aren’t interested in the science (though of course I hope you are) it’s a well made period drama that can be appreciated by all.

Post A Comment »Posted on Sunday 2 November, 2008 at 3:46 pm by Jacob Aron
In Physics, Psychology, Weekly Roundup

Public understanding of science? Sautoy’d

Early this week mathematician Marcus du Sautoy was appointed to the University of Oxford’s Simonyi professorship for the public understanding of science, taking over from Richard Dawkins.

It will be interesting to see how his approach differs to that of his predecessor. I reviewed both Dawkins’ and du Sautoy’s most recent appearances on TV, so if you read those you probably won’t be surprised to hear I’m happy with this decision. Dawkins doesn’t really do science any favours with stunts like the “There’s probably no God” buses, and hopefully du Sautoy will steer away from religion and stick to the science.

Can certain colours make you more attractive? It’s not so red-iculous

Psychologists at the University of Rochester have published a study suggesting that for women, wearing red could make you more attractive. They found that men were also prepared to spend more money on a date with a woman in a red shirt, rather than a blue shirt.

Women shown the same pictures showed no such bias when asked to give an attractiveness rating, suggesting that there is a link with fertility, because as red is the colour of blood it can easily by used by a female animal as an external signal to a partner, according to Dr Jo Setchell, an anthropologist from Durham University:

“For example, a lot of female monkeys have bright red sexual swellings, which show that they are around the time of ovulation.

“There has been controversy over whether, in female humans, ovulation is advertised or not, although there is some evidence that behaviour, such as going out, changes around that time.

“But wearing red could give you an advantage.”

“Seriously, how hard can it be to come up with a pun about coughs?” he said

The New York Times has some rather nice images of coughs, candles, and other “invisible” liquids and gases. They were taken by engineering professor Gary Settles, of the gas dynamics laboratory at Pennsylvania State University, using a technique known as schlieren photography. By using a small, bright light source, lenses, and mirrors along with a razor blade that blocks parts of light beams, it is possible to view and even photograph the disturbances in the air caused by coughing and other phenomena.

Post A Comment »Posted on Saturday 25 October, 2008 at 6:33 pm by Jacob Aron
In Inventions & Technology, Physics, Yes, But When?
Spec-tape-ular: visible light is generated in this 30-second exposure of peeling tape.

A paper in the latest issue of Nature has revealed that peeling sticky tape can produce X-rays.

It has been known since 1939 that tape can produce visible light when peeled. This is called triboluminescence, and is due to the energy released during the breaking of the chemical bonds between the two layers of tape.

The research by a group of scientists at the Department of Physics and Astronomy of University of California in Los Angeles found that in addition to this visible light, tape could also produce X-rays and radio waves, both forms of electromagnetic radiation but with different wavelengths to that of light.

The equipment used in the experiment

They used an interesting looking set-up (left) to search for the X-rays. An automated peeling machine removed the tape with a measurable force, whilst a detector looked out for an X-rays that were emitted. All of the equipment had to be placed in a vacuum, as the X-rays cannot normally be generated otherwise - which means that you’re safe when reaching for the office supplies.

The X-rays are produced as electrons jump from the main roll to the sticky side of the peeling tape. When they hit the other side they slow down, losing energy in the process. This energy has to go somewhere, and it just so happens to come out as X-rays.

It’s not all fun and games however, as the X-ray tape could have useful applications. Medical X-rays are made using costly and bulky equipment, but with some refinements the team believe that inexpensive X-ray machines could be produced for use by paramedics, or places where access to electricity is limited - all you need is a bit of tape. The researchers have applied for a patent on the concept. They were able to produce an image of one of the team’s thumbs:

An X-rayed thumb, produced using tape.
Post A Comment »Posted on Monday 13 October, 2008 at 9:35 pm by Jacob Aron
In Biology, Chemistry, Physics

Those of you who actively follow science news might have been wondering this past week why I hadn’t yet commented on the Nobel Prize announcements. No, I haven’t forgotten in all the course-starting excitement - I just thought it would be more useful to wait until all of the prizes had been announced. Before the results however, a bit of history.

The Nobels have been awarded for over 100 years, with the first prizes given out in 1901. The Swedish chemist Alfred Nobel, wishing to to atone for his inventing dynamite, specified in his will that his fortune should be used as a fund that would celebrate intellectual achievement. He decreed there should be awards given annually to five disciplines: Chemistry, Physics, Physiology or Medicine, and Literature. Later in 1969, a prize for Economics was created in honour of his memory.

I always wondered why there is no Nobel for Mathematics. A story I’ve often heard is that Nobel’s wife cheated on him with a mathematician, but it turns out this story is completely unfounded - for one thing, Nobel was never even married. There is no concrete reason as to why Mathematics was omitted, but many feel it is because Nobel viewed it as a science with little practical benefit for humanity. So there! On to this year’s prizes:

The Nobel Prize in Physiology or Medicine

Half of this prize was awarded to Harald zur Hausen “for his discovery of human papilloma viruses causing cervical cancer.” The second most common cancer in women, cervical cancer is estimated to cause 253,500 deaths worldwide each year. The work done by zur Hausen has lead to vaccines that provide greater than 95% protection against infection by two high risk strains of human papilloma viruses, HPV types 16 and 18.

The other half of the prize was split between Françoise Barré-Sinoussi and Luc Montagnier “for their discovery of human immunodeficiency virus.” By isolating and cloning HIV, their work allowed other groups to prove the virus’s link to acquired human immunodeficiency syndrome (AIDS). Working with the virus to create diagnosis methods and antiviral drugs would not have been possible without the pair’s discovery.

The Nobel Prize in Physics

Yoichiro Nambu received half of the prize “for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics”, whilst one quarter each went to Makoto Kobayashi and Toshihide Maskawa “for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature.”

Symmetry breaking is responsible for the universe around us - without it, we wouldn’t be around to award Nobels! When the universe was created, matter and antimatter particles annihilated each other in a great cosmic battle for supremacy. If there had been an equal amount of particles on both sides, the universe would have been left empty as both matter and antimatter were completely obliterated. It’s thanks to the “breaking” of this matter-antimatter symmetry that matter was able to achieve dominance and lead to the universe we see today. Even one extra particle of matter for every ten billion of antimatter was enough to break the symmetry.

Nambu was the first to mathematically model how this symmetry breaking could occur at the subatomic level, and in doing so helped refine the standard model of particle physics. The symmetry breaking model formulated by Kobayashi and Maskawa suggested an extension of the standard model was required to explain some observations in particle physics, and they hypothesised the existence of third family of quarks, the fundamental particles that make up many matter and antimatter particles. Their model predicted in the 1970’s particles that weren’t observed until the late 1990’s.

The Nobel Prize in Chemistry 2008

The Chemistry prize this year was split an equal three ways, by Osamu Shimomura, Martin Chalfie and Roger Y. Tsien “for the discovery and development of the green fluorescent protein, GFP.” First observed in the jellyfish Aequorea victoria in 1962, this protein is used by scientists around the world to learn more about biological processes.

Pigs with GFP modified DNA glow green.

By modifying a subject’s DNA to attach GFP to another protein as marker, scientists can visually follow the progression of the protein around an organism as it glows green. It can be used to watch the growth of nerve cells, or observe the development of cancer. Following the discovery of GFP, other colours were added to a biologist’s toolkit, allowing further flexibility in their use. One group of researchers even marked the different nerve cells in a mouse’s brain with a multitude of colour, without harming the mouse in any way.

The Nobel Prizes in Literature and Peace and The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel 2008

Whilst great achievements, the other Nobel Prizes fall a bit too far outside the “science” umbrella to discuss here. Nevertheless, congratulations to Jean-Marie Gustave Le Clézio “author of new departures, poetic adventure and sensual ecstasy, explorer of a humanity beyond and below the reigning civilization”, to Martti Ahtisaari “for his important efforts, on several continents and over more than three decades, to resolve international conflicts”, and to Paul Krugman “for his analysis of trade patterns and location of economic activity.”

Indeed, congratulations to all of the Nobel Lauretes (the Nobel foundation does not like to call them winners, because it’s “not a competition or lottery, and therefore there are no winners or losers”) on their fantastic achievements. Who do you think should be up for the honour next year?

Post A Comment »Posted on Friday 10 October, 2008 at 12:40 pm by Jacob Aron
In Physics, Space & Astronomy

Today is the 10th of October, or 10/10. The Eames Office has dubbed this “Powers of Ten Day” in honour of Charles and Ray Eames, who in 1977 created a film that allows one to grasp the diverse scales that make up our world, going up in powers of 10 from a picnic to the vastness of space and back down to a single atom in a human hand. If you’ve never seen it before, it’s well worth a watch:

When I watch this I find it amazing that science has allowed us to see so far out into the universe, whilst also giving us the ability to peer right into the basic building blocks of everything around us. It’s both humbling and awe inspiring, communicating many ideas about the world in a clear, engaging, and easy to understand many. No wonder that “over ten million” have viewed the film. It’s something that I think everyone should see, so I hope you watch it and enjoy Powers of Ten Day!

Post A Comment »Posted on Wednesday 24 September, 2008 at 9:48 am by Jacob Aron
In Physics

Last week when it was announced last week that the Large Hadron Collider would have to be shut down for two months, I suggested that this could potentially conflict with the planned shut down in December. It seems that this is now officially the case. CERN engineers have stated that the collider will have to be offline until “spring 2009″ whilst they make repairs.

It’s a real shame considering the very successful launch on September 10th, where progress actually exceeded expectations. Still, the guys and gals at CERN are in it for the long haul - the particle collider took 13 years to build and another two to be ready for “switch-on”. It could also be years before substitutional results start to emerge from the experiment, so a few months delay is not the end of the world. Still, the downtime must be incredibly frustrating for all involved.

Many have called the LHC a cathedral of the 21st century. I’m not sure I like the “science is the new religion” implications, but in terms of sheer construction and engineering, it’s certainly an apt comparison. If you have checked out the facts and figures of the LHC, they make for interesting reading. Did you know that the LHC…

…is 26,659 metres long, but sends proton beams whizzing round 11,425 times a second?

…cooled to -271.3°C (1.9 K), but 100,000 times hotter than the sun when proton beams collide?

…will provide enough data to fill 100,000 DVDs a year?

Amazing stuff, but I guess we’re all going to have to wait until spring 2009 to see it in action.

1 Comment »Posted on Saturday 20 September, 2008 at 4:34 pm by Jacob Aron
In Physics

After all the fuss over the switching on of the Large Hadron Collider, it turns out the experiment will have to be shut down again.

The LHC has to operate at temperatures near absolute zero, otherwise the superconducting magnets that hold the proton beams in place won’t work properly. On Friday, around 100 of these magnets suffered a failure which caused a rapid rise in temperature, known as a quench. The magnets went up almost 100 °C, leaving them around a still comparatively chilly -170 °C, but much too hot to retain their superconducting properties.

The tunnel sector where the failure occurred will now have to be warmed up even further to allow engineers to perform repairs, and then cooled back down to its operating temperature of 1.9K. The process will take two month, says CERN spokesman James Gillies:

“A full investigation is still under way but the most likely cause seems to be a faulty electrical connection between two of the magnets which probably melted, leading to a mechanical failure. We’re investigating and we can’t really say more than that now. But we do know that we will have to warm the machine up, make the repair, cool it down, and that’s what brings you to two months of downtime for the LHC.”

As I recall, the original plan was to shut down the LHC over the Christmas period, presumably as researchers would be taking a break for some festivities. If they aren’t up and running until two months from now that will be approaching December, so I wonder if the planned shut down will still go ahead.

You can actually follow the temperature status of the LHC online. In the bottom left-hand corner, you can see that sector 3-4 has experience a spike in temperature up to nearly 100K. This page gives more detail, showing the spike occurring between lunchtime yesterday and midnight. I think it’s pretty cool that all of this information is accessible to anyone online.

As an aside, the Telegraph have a story about the difficulty in communicating the energy used by the LHC. Apparently, with a beam energy of 10 trillion watts, the LHC could defrost a pizza in just 30 nanoseconds, according to J R Minkel of Scientific American. Dr David Sankey of the Rutherford Appleton Laboratory disputes his figures, saying that because the protons are arranged in bunches it would actually be almost 1000 times quicker, at 250 picoseconds. I’ll keep you up to date with an further LHC pizza news, as it happens.

Post A Comment »Posted on Saturday 13 September, 2008 at 3:36 pm by Jacob Aron
In Physics

First there was a rap, and now the Large Hadron Collider has a game. Unfortunately it’s not as good as the rap, but it will teach you what the LHC is for, and how it works.

First, you must help accelerate protons up to speed, then adjust the magnets to get them following around the ring, and finally use quadrupole magnets (which I had never heard of, so it’s educational!) to focus the proton beams. Only after completing these tasks can you push the big red button and start the LHC.

Just in case you are still worried that pushing the red button might create a black hole and kill us all, a handy website has been created to put your mind at ease. Simply point your browser at www.hasthelhcdestroyedtheearth.com for up the minute information on the status of the planet. There’s even an RSS feed!

Post A Comment »Posted on Thursday 11 September, 2008 at 2:43 pm by Jacob Aron
In Physics

The most impressive moment of the Beijing 2008 Olympics was when Usain ‘Lightning’ Bolt not only beat the world record for the 100 metre dash, but actually slowed down to celebrate whilst doing so. A group of scientists from the Institute of Theoretical Astrophysics at the University of Oslo in Norway wondered what Bolt’s record could have been if he kept up his speed. Led by Hans Eriksen, they analysed television footage of the race in their spare time.

By examining the footage frame-by-frame, they found that its possible Bolt’s 9.69 seconds record could have been improved to as low as 9.55 seconds. They began by creating a standard ruler - in the form of bolts on the rail of a moving camera - from which to take their measurements, and then read off the positions of Usain Bolt as well as those of runner up Richard Thompson. Along with these they noted the time on the screen clock.

The camera angle changes from almost front-on to parallel with the track during the course of the race, so the team had to factor the uncertainty of their measurements into the figures. They could then fit a curve to the data, and estimate the distance, speed and acceleration of both runners during the course of the race. They found that the pair are neck and neck for the first four seconds, and the gold medal is “essentially won” between four and eight seconds into the race, after which point Bolt started to slow down. Interestingly, Thompson was actually going faster than Bolt at this point, but he was too far behind to catch up.

Working on two assumptions, the team calculated two potential world records. The first, in which Bolt maintains the same acceleration as Thompson for the rest of the race, nets the runner a 9.61 second world record. If he had been able to keep his acceleration 0.5 m/s2 above that of Thompson, then the time would have been 9.55. They even mocked up a picture of Bolt’s potential win:

In this mock up, the projected Bolt (right) is even further ahead of his competitors than the real Bolt (left)

Given the uncertainties in the data however, the team speculate that 9.52 seconds “does by no means seem to be out of reach.” In fact, because there was no wind at Beijing, and the International Association of Athletics Federations allows a world record to stand with a wind speed under 2 m/s, “a new world record of less than 9.5 seconds is within reach for Usain Bolt in the near future.”

1 Comment »Posted on Wednesday 10 September, 2008 at 9:15 pm by Jacob Aron
In Physics

Two arms, two legs, a head and everything. Beams have been circulated both ways, so congratulations to everyone at CERN - the Large Hadron Collider works! Let the science begin.

I woke up this morning and began watching coverage of the Large Hadron Collider on BBC News. They kept referring to the gigantic machine as “this generation’s moon landing”, but the trouble with the comparison is that the LHC does not fair well on television. There is no “one giant leap” moment, no easy sound bite.

A large amount of screen time was devoted to a room of scientists clapping occasionally as the beam of protons made its way around the full 27 kilometres of the LHC circuit, with the BBC presenters helpfully chiming in “I don’t know what they’re clapping about.” They had Simon Singh on, who was doing his best, but as with most live news coverage it boiled down to “nothing’s happening, nothing’s happening…wait…wait…I’m just being told that nothing’s happening.”

On the newspaper/internet sides of the media, its clear that the LHC is big news. Most papers are running stories pretty close to the front page, and online the scientists at CERN are topping the “most read” charts. Obviously, there is a huge public interest in the LHC.

BBC Radio 4 is by far the leading source of information for those wanting to learn more, with a substantial number of programmes for “Big Bang day”. I didn’t catch Andrew Marr on Today (I’d been wooed by pictures to BBC News), but with the aid of iPlayer I’ve managed to check out most of the offerings. Some links (for the next seven days only, unfortunately) and my reviews:

Engineering Solutions

In the first dedicated programme of the day, Adam Hart-Davis talks to the scientists and engineers at CERN who built the world’s biggest machine. Its nice to hear directly from the people who worked on the LHC, even if much of the conversation consists of Hart-Davis’ astonishment at some large number. The programme also highlights the international nature of the project, with men and women from a number of countries contributing. Worth a listen in order to get a more personal feeling for the events at CERN.

Woman’s Hour

Woman’s Hour began with a recap of the days events so far by Andrew Marr, and then moved on to a discussion with four female scientists, including one from CERN. They talked about the need to get girls more involved with science, and to show that that subjects such as physics are not just for boys. The female population of CERN makes up only 10% of the total, so its an issue that needs to be rectified. The panel suggested introducing girls to female scientists, as well as showing them how science benefits their everyday lives, could help with this.

The programme also featured interviews with female scientists at CERN, who talked about balancing their scientific work with family life. A common theme was the difficulty in taking a break from a scientific career in order to raise a family; in a fast moving fields, a few years out of the loop could mean it was almost impossible to return.

Physics Rocks

Presented by CERN physicist Brian Cox, who before become a scientist played with the band D:Ream - their hits included the New Labour anthem “Things Can Only Get Better” - Physics Rocks speaks to celebrities about their interest in physics.

Guests included the actor Alan Alda and his friend, physicist Brian Greene, who collaborated with him to create the World Science Festival in New York. A huge fan of science, Alda had even designed a t-shirt for CERN. The pair talked about what the possibility of parallel universe could mean for us.

Comedian Dara O’Briain flaunted his BSc in mathematical physics, and suggested that experiments like CERN are great for improving interest in science, whilst John Barrowman (who will pop up again as Captain Jack in the next programme, Torchwood) thought that CERN is “science fiction” and could be creating a “mini-universe”. Not too sure about that one.

Its one of the more light hearted programmes on offer today, as illustrated by Cox on homoeopathy: “how big a particle accelerator would we need to detect bullshit?”, but he views this irreverence as essential to bringing science to the heart of our culture.

Torchwood: Lost Souls

As the first radio episode of the Doctor Who spin-off, I wasn’t expecting too much from Torchwood. A bit naff even at its best, the prospect of an “edutainment” episode did not inspire confidence. It seems I was right to be sceptical, as the first half of the programme mainly consisted of characters talking about just how fascinating it all is.

“Something’s going on at the LHC!”
“The LHC, what’s that?”
“Well, the LHC is…[insert Wikipedia article here]”

Slightly condescending, to say the least. As for the actual plot, it turns out the testing of the LHC has opened up a portal allowing neutron-devouring aliens to come through, leading to the disappearance of 12 people at CERN. There’s some nonsense about the LHC being a gateway to heaven, and then our hero Captain Jack utters the dreaded phrase “reverse the polarity!” This allows him to seal the portal by colliding beams of protons and anti-protons (the real LHC only collides proton beams) and find the Higgs boson in the process. Oh dear.

The episode at least had a few nods for Torchwood fans, with the neutron-eating aliens impersonating two characters who had recently died on the show, and a speech about just how wonderful the human race is in our pursuit for knowledge, did produce this nice little gem: “sometimes, just asking the question is the answer.”

All this, and I’ve not even covered half the programmes on offer. Simon Singh talked about anti-matter in 5 Particles, Front Row was devoted to the representation of physics in the arts, and even as I post this The Great Big Particle Adventure is airing more interviews with CERN scientists. Finally, The Genuine Particle is a satire set in CERN, broadcast at 11.30. I’m looking forward to catching up with the rest tomorrow. Well done Radio 4, for some excellent coverage.

Post A Comment »Posted on Tuesday 9 September, 2008 at 2:04 pm by Jacob Aron
In Getting It Wrong, Physics

The Today programme had Professor Stephen Hawking on this morning, taking about (what else), the Large Hadron Collider. He reiterated much of what I’ve said this past week, namely micro black holes are unlikely to be produced, and even if they do crop up, we’re perfectly safe.

Hawking also agreed with my comments yesterday about the immediate benefits of the LHC, stating science for the sake of science is enough for now:

“Throughout history, people have studied pure science from a desire to understand the universe, rather than for practical applications, or commercial gain. But their discoveries have later turned out to have great practical benefits. It is difficult to see an economic return from research at the LHC, but that doesn’t mean there won’t be any.”

He also pointed out that together the cost of the LHC and the space program (which Hawking also views as vital to the survival of the human race) cost less than 0.1% of world GDP - which we should easily afford. Hawking himself could be out of pocket, as he has a bet against the discovery of the Higgs boson - to the tune of $100. He thinks it would be more “exciting” not to find the Higgs, as it would mean something is wrong with the Standard Model of particle physics.

It’s good to hear from Hawking on the LHC. He’s arguably the most famous living physicist, even if many people remember him for his disability rather than his discoveries. Hopefully the general public will have read his books or seen him on TV, remembered him as an interesting and reasonably sane guy, and take his word for it - we’re not all going to die tomorrow, but we are witnessing an extremely important piece of science.

2 Comments »Posted on Monday 8 September, 2008 at 6:03 pm by Jacob Aron
In Getting It Wrong, Physics

It seems the media pendulum is swinging back in favour of the Large Hadron Collider, with both the Times and the Sun reporting the particle accelerator could lead to “improved cancer treatments, systems for destroying nuclear waste and insights into climate change.”

The claims, presumably put out by CERN as damage control, are pretty impressive. Apparently cancer cells could be destroyed using particle beams containing “protons, carbon ions and even antimatter.” Antimatter can be produced by the proton synchrotron, part of the system which accelerates beams before injecting them into the LHC, but I’m not really sure how that helps kill cancer. The LHC isn’t the first machine to create antimatter, so what is being done here that is new?

CERN will also use the proton synchrotron in a new laboratory investigating the interactions of cosmic rays and clouds. If cosmic rays fired into a “cloud chamber” form clouds, it could have “interesting implications.” Very promising, I’m sure.

I don’t really want to bash the guys at CERN, but come on. The similar wording in both articles indicates cribbing from a press release (although I can’t find one on CERN’s site) providing journalists with some tenuous links to hot issues in science, as away of getting some positive press for the LHC.

I’d rather see a spin on the actual science taking place at CERN, rather than some “maybes” around the periphery. Yeah, the discovery of the Higgs boson might not immediatly lead to some wonderful technological revolution, but that’s not what science is about. Imagine if Newton had publicised his explanation of gravity as “Great News For Farmers - A New Method Of Collecting Apples Is On The Way!” He had no way of knowing that his calculations would eventually be used to put men on the moon - that’s just not how science works.

CERN should be celebrating their efforts of discovery, not pandering to a fickle media - although if the LHC can make my whites “whiter than white”, I’m all for it.

3 Comments »Posted on Saturday 6 September, 2008 at 6:15 pm by Jacob Aron
In Getting It Wrong, Physics

As we draw closer to the official “switching on” of the Large Hadron Collider, the mainstream media is increasingly running stories on the possibility of the destruction of the universe. A quick summary:

I can see the appeal of such stories. EARTH SUCKED INTO BLACK HOLE!!! is an impressive headline, and sure to shift a few newspapers. Unfortunately for editors, it’s just not going to happen. The LHC Safety Assessment Group have reviewed the dangers and found that there are “no reasons for concern.”

The LHC is the largest particle accelerator ever built, but that doesn’t mean that the collisions within it have never taken place before. In fact, cosmic rays have been colliding in the Earth’s atmosphere for billions of years, and have already generated the equivalent of a million LHC experiments. As you have probably notice, the planet still exists. Staggeringly, more than 10 million million - that’s 10,000,000,000,000 - LHC-like experiments are conducted every second across the universe.

The same goes for microscopic blank holes, which the media believe could sink to the centre of the Earth and consume us all. If that were true, it would have already happened, either here or else where in the universe. The continued existence of dense bodies such as neutron stars rules out this possibility, as they would attract “natural” microscopic black holes and be destroyed. Other exotic phenomena such as strangelets (hypothetical lumps of “strange matter”), vacuum bubbles and magnetic monopoles have also failed to occur during cosmic ray collision, so they’re ruled out as well.

All of these occurrence are what I mentally lump into the “too interesting to actually happen” category. They join things like alien invasions, teleportation and mind-reading. When you can make a decent sci-fi flick out of the concept, it probably isn’t going to happen.

So, why isn’t this being communicated by the majority of the mainstream media? The legal case filled by the likes of Professor Otto Rössler probably doesn’t help. Rössler, along with other scientists, submitted their case to the European Court of Human Rights, claiming that the LHC violates the rights to life and private family life which are provided under the European Convention of Human Rights. “Look,” says the media. “Even the boffins think this collider thingy will blow up the world. Someone stop the mad scientists!”

I have to wonder how many retractions will be printed come next Wednesday, when newspapers find that their offices are still around. Somewhere between none and zero, I reckon. The event will be ignored by the public at large, many of whom will say “oh, they just got lucky,” and continue to believe scientists will destroy us all.

Post A Comment »Posted on Sunday 24 August, 2008 at 12:05 pm by Jacob Aron
In Biology, Inventions & Technology, Physics, Psychology, Weekly Roundup, Yes, But When?

Going, going, found!

A new species of insect was found this week - on eBay. Dr Richard Harrington, vice-president of the UK’s Royal Entomological Society, paid £20 for a 40-50 million-year-old fossilised insect trapped in amber. After struggling to identify it he sent the purchase to Professor Ole Heie, an aphid expert in Denmark, who confirmed it was a previously undiscovered type of aphid.

Professor Heie named the insect Mindarus harringtoni after its purchaser, but Dr Harrington himself had wanted to go for something slightly more unorthodox. “I had thought it would be rather nice to call it Mindarus ebayi,” he said. “Unfortunately, using flippant names to describe new species is rather frowned upon these days.”

Because you can’t just have one…

If you are trying to lose weight, going for a small bag of crisps rather than a larger one might seem the obvious route, but researchers from the Technical University of Lisbon and Tilburg University in the Netherlands have found that this may not be the case. Participants in a study were asked to complete a questionnaire on body satisfaction and dieting, then weighed and measure in front of a mirror in order to active their “dietary concerns” - in other words, to get them to watch their weight. Along with a control group who had not had their “dietary concerns” activated, they then watched episodes of Friends (aside: why Friends? Perhaps due to its constant looping on E4…) and were asked to evaluate the adverts.

In fact, the researchers were watching their consumption of the crisps that had been provided. Available in large or small packaging, the study found the “dietary concerns” group given large packages at the fewest number of crisps. The conclusion was that large packages made participants think of overeating and dieting, but small packages were “innocent pleasures” that did not trigger dieting concerns. My conclusion: I now want some crisps.

Power adaptor tyranny could soon be over

If you’re anything like me, you’ve got a few gadgets. When ever I travel anywhere I have to take a mess of power adaptors to feed my phone, mp3 player and Nintendo DS - I’m just thankful I don’t have a laptop to add to the mix. It’s also easy to forget to plug the damn things in, leaving me to play the “do I have enough battery life to make this call?” game. I’ve often thought of a solution - a “power pad” on my desk, where any electrical device would charge simply by being left there and forgotten about.

The technology exists - your electric toothbrush is charged not by wires, but by magnetic induction. Flowing electrons in a circuit generate a magnetic field which in turn induces electron flow in nearby circuits - bam, wireless electricity. I had assumed that the process was too slow to be of use with general electronics, and left it at that.

Turns out I should have got to work on a prototype, because MIT and Intel have found a way to make it work - and not just in close contact. They demonstrated a 60-watt light bulb powered by an energy source three feet away, with no wires in sight. The technology is at least five years away however, especially one-quarter of the energy is lost in transmission. In a world increasingly looking to improve energy usage, 75% efficiency is pretty unacceptable. Still, I can’t wait to get rid of those chargers.

Post A Comment »Posted on Sunday 17 August, 2008 at 4:52 pm by Jacob Aron
In Biology, Physics, Weekly Roundup

Nanoscientist Chad A. Mirkin use a new technique called Polymer Pen Lithography to create the microscopic Olympic logos, shown below. The technology allows a single device to print at three different sizes and could be used in a range of industries, from computing to medicine. The Olympic logo perfectly demonstrates the use of these differing scales. The text is made up of around 20,000 dots that are 90 nanometres in diameter, whilst the Olympic rings and stylised athlete are made from approximately 4,000 dots that are 600 nanometres in diameter. The switch in scale is made possible by applying increasing pressure to the nano-pen, which causes the tip to deform and become wider. For finer work, it snaps back into place when the pressure is released.

Tiny Olympic logos, 70 micrometers long and 60 micrometers wide.

If you have a terrible singing voice, it might not be because you’re tone deaf - you could just be a bad singer! Neuroscientists at the State University of New York at Buffalo and at Simon Fraser University have suggested that poor perception of tone is just one possible explanation for awful singing. You could also have poor control of your vocal chords, the inability to imitate what it is you hear, or simply a bad memory. The research has shown that being unable to reproduce a note that you have heard is the most likely explanation - your ears, brain and vocal chords just can’t get coordinated. Something to bear in mind for your next solo in the shower!

Post A Comment »Posted on Sunday 10 August, 2008 at 7:02 pm by Jacob Aron
In Chemistry, Getting It Wrong, Physics, Weekly Roundup

The Guardian reports on the Advertising Standards Authority’s decision to allow Miracle Gro to advertise their organic compost as “100% chemical free”. The ASA’s reasoning is that viewers understand the word “organic” to mean no man-made chemicals are used in the manufacture of a product, so the advert is permissible. I’m not quite sure how a compost without any chemicals would be beneficial to plants, so it seems Miracle Gro are playing on the commonly held beliefs that chemicals, particularly man-made chemicals are inherently bad, and “natural” and “organic” products are free from such nasty things. Tut tut.

Scientists at Cornell University in Ithaca, New York have used graphene, a material made from carbon that is one atom thick, to create the world’s smaller balloon. They produced membranes innumerable to gas that measured from 1 to 100 square micrometres in area and 0.25 to 3 micrometres deep. A micrometre is one millionth of a metre, meaning around 1.5 million of these balloons could fit on your thumbnail. If only they could work out a way to write “Happy Birthday” on them. Until then, the suggested uses of the balloons include tiny weighing devices and pressure sensors.

Post A Comment »Posted on Friday 8 August, 2008 at 12:12 pm by Jacob Aron
In Physics

It turns out that the Large Hadron Collider is not actually being switched on today - although that depends on you definition of “switched on”. It was my understanding that when the LHC had been cooled to nearly absolute zero,a very chilly 1.9 Kelvin (that’s -269.1 degrees Celsius), it would be put into operation. What this actually means is the scientists at CERN can begin firing proton beams through a small part of the LHC, in preparation for the first full circuit which is due to take place on September 10th - the official start-up date. They are testing the synchronisation of the LHC with the Proton Synchrotron (PS) and Super Proton Synchrotron (SPS), which get the proton beams up to the high energies required before injecting them into the LHC. Essentially, they’ve pushed the power button but it hasn’t finished booting up yet.

With that clarification out of the way I’ll get on to the real point of this post: what exactly is the LHC, and what does it do? Those of you who watched the LHC rap I put up yesterday may have some idea, so I’m sorry if my explanation is slightly less entertaining.

An ariel view of CERN, on the Swiss-French border. The biggest ring is the LHC itself, whilst the smaller rings are the Proton Synchrotron and Super Proton Synchrotron. Click for a larger image.

The LHC is the latest (and largest) particle accelerator to be built. A particle accelerator is exactly what it sounds like - it accelerates electrically-charged particles (such as the positively charged proton) to near the speed of light, and then the “Collider” part of the LHC steps in. Two beams are sent whizzing around the ring in opposite directions as they build up to speed, held on course by powerful superconducting magnets. Superconductivity allows the flow of particles with very little electrical resistance, but can only take place at extremely low temperatures - hence the cooling of the LHC.

A simulated collision in the LHC

When the two proton beams collide they explode into a mass of exotic particles. The particle the scientists are interested in finding is the Higgs boson. First theorised in 1964 by Peter Higgs (amongst other), the Higgs boson is basically a particle associated with the Higgs field, which tells other particles what their mass should be. The Higgs field covers the entire universe, and it’s as if heavier particles such as the top quark (one of the basic building blocks of matter) struggle to “swim” through the field, where as massless particles such as the photon don’t interact with it at all.

The trouble is, we can’t see this field. However, all fields have a particle associated with them (for example, the photon is responsible for electromagnetism) which means that if the Higgs boson is detected, this will prove the existence of the Higgs field and validate the Standard Model of particle physics. If the Higgs boson cannot be found, then something is wrong with the Standard Model, and a lot of physicists will be left scratching their heads. Hopefully once the LHC is in action it will be the former, and not the latter.

Post A Comment »Posted on Thursday 7 August, 2008 at 2:52 pm by Jacob Aron
In Getting It Right, Physics

Tomorrow should see (if all goes to plan) the switching on of the Large Hadron Collider, a massive particle accelerator which scientists hope will enable them to pin down the elusive Higgs boson. I’ll be posting more about the collider tomorrow, but until then, enjoy the LHC rap:

Yes, it’s pretty silly, but it actually has a decent amount of scientific content. See you tomorrow for something slightly more sensible!