The Great Beyond

Einstein’s often-debated views on religion look to have been made clearer by a document up for auction tomorrow.

“The word god is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honourable, but still primitive legends which are nevertheless pretty childish,” he writes in the 1954 letter to philosopher Eric Gutkind.

Bloomsbury Auctions, which is selling the letter, expects it to go for between £6000 and £8000 (press release). If you don’t have that much spare change, you can always read Einstein’s 1940 Nature article ‘Science and Religion’ (subscription required).

Continue reading "Einstein: ‘god is human weakness’" »

Posted by Daniel Cressey on May 14, 2008
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Physicist John Wheeler died on Sunday aged 96.

“For me, he was the last Titan, the only physics superhero still standing,” says Max Tegmark, a cosmologist at the Massachusetts Institute of Technology (NY Times).

His description of General Relativity remains one of the best there is: "mass tells space how to curve, space tells mass how to move".

Daniel Holz worked with Wheeler and has written a wonderful tribute at the Cosmic Variance blog. On Wheeler’s work he notes:

He did foundational work on quantum mechanics, collaborating with Niels Bohr on some of the earliest work in nuclear fission. He invented the S-matrix. He played important roles in both the Manhattan project (atomic bomb) and the Matterhorn project (Hydrogen bomb). He made major contributions to general relativity, co-authoring with Charlie Misner and Kip Thorne the bible of the field. He was legendary for his way with words, coining such terms as wormholes, quantum foam, black holes, and the wave function of the Universe (the Wheeler-DeWitt equation). He trained generations of students; one of his first was Richard Feynman.

He also notes what he was like as a person, with this my favourite detail:

He would always take the stairs. (‘ No time to wait for an elevator!’) He would hook his arm into the banisters, and swing around, practically leaping from one flight to the next. This was 1990; Wheeler was 79 years old.

More tributes below the fold as they come in.

Continue reading "RIP John Archibald Wheeler" »

Posted by Daniel Cressey on April 14, 2008
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A surprising number of quite dramatic stories today – one big round-up post will have to do for them all.

Dextre, the Canadian space agency’s new robot, is meant to be helping construct the ISS. Instead it’s making outlandish demands:
In a surprising and potentially troubling request, the new space station robot known as Dextre demanded that astronauts refer to it in the future at ‘Dextre the Magnificent.’ Brandishing power tools that would make any handyperson blush, the mobile servicing system thanked humans for creating it and promised a glorious future where humans would retain an important role in the new robot order.

Virgin and Google are going to Mars. They want YOU to join them (if you can score highly enough on their selection questionnaire that is).

Continue reading "A chemist, a physicist, and a biologist walk into a bar" »

Posted by Daniel Cressey on April 01, 2008
Categories: Biology & Biotechnology, Chemistry, Earth, environment & ecology, Health and medicine, Neat technologies, Physics & Mathematics, Policy, Space and astronomy | Permalink | Comments (0) | TrackBacks (0)

Of all the physics conspiracy theories out there, my current favorite concerns the Large Hadron Colldier (LHC), a proton-proton collider near Geneva, Switzerland that will hopefully discover some exciting new physics. Conspiracy nuts have suggested that it might also inadvertently destroy the Earth (or maybe even the entire Universe).

I'll spare you the details, which can be easily dug up with a little Googling, but basically the cranks think that the collider will also cook up either an exotic particle or a tiny black hole that will suck up everything around it. It's pretty much bunk, as others smarter than I have said (here for example).

But that hasn't stopped Walter L. Wagner, a botanist and self-proclaimed nuclear physicist, from filing suit in US District Court in Hawaii to stop the LHC before it destroys all we hold dear. Wagner wants a "full-scale safety analysis" to be conducted of the collider before its start up, hopefully later this year. A few years back, Wagner raised the same concern about the Relativistic Heavy Ion Collider at Brookhaven National Laboratory on Long Island. But all it ended up doing was producing these pretty pictures (and some valuable science too).

Incidentally, Wagner's in a little legal trouble of his own. According to the Honolulu Advertiser, he and his wife were just indicted for allegedly taking illicit control of some property owned by the World Botanical Gardens, which he helped found.

I'm guessing not even the LHC can make his problems disappear.

Credit: CERN

Posted by Geoff Brumfiel on March 28, 2008
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There’s a story doing the rounds at the moment that Colombian rebel group FARC is planning to make a ‘dirty bomb’ out of uranium. This story first blew up last week and has been recycled ever since, and it’s not really true.

The government has seized 30 kg of “radioactive” depleted uranium according to a number of reports. Except depleted uranium is barely radioactive. It’s dangerous alright, but only when made into tank shells.

It is toxic, but so are most heavy metals. You’d be better off making a dirty bomb out of mercury than DU.

The head of Colombia's armed forces says a buried cache of uranium was found thanks to information from those close to an arms dealer whose name was found on a computer belonging to deceased rebel Raul Reyes (Bloomberg). “It’s exactly the same material listed on Reyes’ computer. Why the FARC were so anxious to obtain this material we still don’t know,” says General Freddy Padilla.

Pro-FARC news agency ANNCOL has rubbished the claims.

Below the fold are a couple of people who got it right about depleted uranium.

Continue reading "Colombian uranium nonsense" »

Posted by Daniel Cressey on March 28, 2008
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Today is Pi day – in American nomenclature March 14th is 3.14. The official Pi day website is com-π-ling a list of people’s favourite Pi day activities, most seem to revolve around the remarkably obvious eating of pies.

Also celebrating pi day:

A remarkably indepth article from the BBC
Freep.com is running a Pi-themed haiku contest. Somehow they have missed the opportunity to call it a pi-ku contest. Fools!
The NY Times is also running a poetry of Pi competition, and offering a pi-rize
Rush-Henrietta Central School students smashed their maths teachers in the face with pies, which seems quite harsh (Democrat and Chronicle).
Nature article from 2007 on Pi day

Today is also international ‘Talk Like A Physicist Day’ – March 14th is Einstein’s birthday...

Continue reading "Thank God it’s π Day" »

Posted by Daniel Cressey on March 14, 2008
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A Polish physicist and priest has won the annual million-dollar Templeton Prize for “progress toward research or discoveries about spiritual realities”.

Michael Heller walks away with $1.7 million for investigating questions including whether the Universe needs to have a cause (press release). This is the largest annual prize given to an individual (just bigger than the $1.6m Nobel), and comes from the same foundation that has previously funded studies into whether prayer can heal the sick, and how a nun's religious experience looks under a brain scanner.

“I always wanted to do the most important things, and what can be more important than science and religion? Science gives us knowledge, and religion gives us meaning. Both are prerequisites of the decent existence,” Heller told the New York Times.

According to the London Times:

His theories do not so much offer proof of the existence of God as introduce doubt about the material existence of the world around us. He specialises in complex formulae that make it possible to explain everything, even chance, through mathematical calculation.

Continue reading "Physicist-priest wins $1.7 million prize" »

Posted by Daniel Cressey on March 13, 2008
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Earlier this week an interesting maths press release popped up in my inbox. Despite the nice premise – researcher solves problem that has vexed community for 140 years – I didn’t cover it.

The reason for this was the actual research paper was nearly a year old. Who, I reasoned, would want to read about something a year old. Well plenty of people did cover it, and there has since emerged and interesting twist...

Science’s coverage adds a classic science bun-fight: a row over who actually got there first.

Continue reading "Who really solved 140-year old maths problem?" »

Posted by Daniel Cressey on March 07, 2008
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The troubled body in charge of a large chunk of UK physics funding has just announced what it likes and what it doesn’t. Faced with something of a budget shortfall (see Nature from December, January, January again, and again) the Science and Technology Facilities Council has now ranked its projects.

STFC’s new Programmatic Review document rates projects as high, medium-high, medium-lower, and lower priority. “Obviously those in the lower categories are those most at risk,” the document says, ominously (PDF).

So what does it seem UK physicists can do without? Here are some of the lower priority projects:

Gemini [ground based telescope]
UKIRT [“world’s largest telescope dedicated solely to infrared astronomy”]
Ground-based Solar Terrestrial Physics facilities
CLF lasers for science programme [provides lasers for science]
High Performance Computing Operations

Luckily for some of those about to get their marching orders, the STFC is quick to point out it’s not because they're not doing good science. It’s because some of the lower priority projects don't have “strategic fit to STFC”.

Continue reading "UK Physicists – check your job security here" »

Posted by Daniel Cressey on March 04, 2008
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An intriguing paper in Physical Review Letters this week reports on an international team’s efforts to dig deep into the Standard Model of physics. The paper itself (PRL) is very technical (not to be attempted by the faint-hearted). But the Edinburgh University press release on the work (not available online, sorry) gets the quote-of-the-day prize for this succinct summary:

Professor Richard Kenway of the University of Edinburgh's School of Physics said: “Although the Standard Model has been a fantastic success, there were one or two dark corners where experimental tests had been inconclusive, because vital calculations were not accurate enough. We shone a light on one of these, but to our enormous frustration, nothing was lurking there.”

According to the press release, the team used a supercomputer to compare recent experiments studying the decays of bottom quarks to be compared with earlier, strange quark experiments (that’s experiments on strange quarks, not strange experiments on quarks). The comparison result agrees with the predictions of the Standard Model of particle physics and implies that the particle-anti-particle asymmetry (technically known as "CP-symmetry violation") seen in these two different decay processes have a common origin.

In other words they confirmed the six-quark theory of particle-anti-particle asymmetry.

In other, other words they confirmed what they thought they knew about quarks, and didn’t find anything new. That may be disappointing to people looking to push the boundaries of physics, but I must admit to being a bit relieved: surely we have enough mysteries in the world of particle physics, thanks very much, without turning up new ones.

Posted by Nicola Jones on February 26, 2008
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It must have seemed like a great idea at the time, at least until science got involved. Rather than powering your floor lamps by nasty, carbon footprint increasing mains electricity why not use gravity?

That’s what Virginia Tech student Clay Moulton thought. So he designed the Gravia, a metre high lamp powered by a slowly falling weight that users would lift to the top. As the weight falls, the theory goes, it can be used to power LEDs – producing 600-800 lumens, about the same as a 40-watt bulb over a period of four hours (press release).

Although it hasn’t been built, Gravia even came second in a Greener Gadgets Design Competition. Websites praised it.

Then people started crunching the numbers…

One person noted on a Slashdot discussion:

The drop is 58" according to the plan [core77.com]. This gives about 0.022W at 100% efficiency.
For reference, the highest efficiency LEDs that I know of get 131 lumens per watt. If we're generous and allow them 150 lumens/watt, they still need 4W of power. This would require a drop of 255 metres using the 50lbs of weights he claims. Since we can't really go above 1.5m high, we'll need almost 4 tonnes of weights.

Later some estimates of the number creep up to 24 tonnes (ZD Net). It doesn’t seem likely this light is going to be in your shops anytime soon. We’re expecting a statement from Virginia Tech soon…

Read the university response in full below the fold.

Continue reading "Heavy work for green light" »

Posted by Daniel Cressey on February 21, 2008
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Posted for Katharine Sanderson

It might have passed you by, but at the Grammys last week a bunch of mathematicians and their algorithms walked away with a gong. The award was for “best historical album”, and was a remastering of the only known bootleg recording of Woodie Guthrie, the American folk musician (press release).

The award went to Kevin Short, a mathematician at the University of New Hampshire, and engineers at Jamie Howarth’s company Plangent Processes who developed algorithms to remaster a particularly fragile and crackly tape recording of Guthrie performing in 1949 (buy it here).

Apparently the software developed by the team recreates the machine on which the original performance was recorded and so can cancel out the wobbles and strange speed delays caused by the flimsiness of the tape. Here’s an explanation of the process with sound effects and all on NPR – explaining that the acetate tapes break down into vinegar, which causes the warping we hear as a that rather disturbing wah-wah effect.

Or go straight to the before and after sounds of the Grammy winning Guthrie performance.

Congratulations to maths.

Image: Kevin Short holding the album and his Grammy medallion / Douglas Prince, UNH Photo Services

Posted by Daniel Cressey on February 13, 2008
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There’s much excitement in the UK media over a story broken by New Scientist that nerves can be grafted over injured sections of spinal cord in rats.

At a conference in New York, John Martin of Columbia University described how he and his colleagues cut motor nerves away from the abdominal muscles they normally connected with. They then stretched the cut ends of these nerves down past injury sites on the rats’ spines and glued them in place, says the magazine (subscription required).

Later the researchers found their grafted nerves had begun to form connections with motor nerves below the injuries. “Zapping the spinal cord above the injury made the lower limbs of the rats twitch, showing that motor signals had begun once again to pass along the entire length of the spine,” NS reports.

Giorgio Terenghi, of the University of Manchester in the UK, told the BBC, “It’s a very good idea, but the key thing is how much function they will be able to restore using this technique.” The research has not yet been published in a journal.

How much function is being restored in rats, let alone humans, is unclear at the moment. Nevertheless it is predictably being hailed as a potential cure for victims of paralysis (eg, Daily Mail, Guardian, PA).

RelatedRecent Nature medicine paper on recovery after spinal injuries.
Great Beyond post on the above paper.

Image: Getty

Posted by Daniel Cressey on February 07, 2008
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A new world record in human powered computing has been set by MIT students who used bicycles to power one of the institute’s supercomputers for 20 minutes. As part of the ‘Innovate or Die’ pedal-powered machine contest a nuclear fusion reaction was modelled by the sweat of the students’ brows.

More arithmetic calculations were computed “than were done on the entire earth up to 1960”, according to Techworld. A very energy efficient supercomputer was used though – a chip in the SiCortex machine apparently uses about 8 watts of power, compared to an average laptop chip that could draw 100 watts (Xconomy). Of course there is more than one chip in the supercomputer – Techworld says the “low-powered” system drew 1,200 watts.

“By harnessing the energy creation processes of the sun, our research opens the possibility of limitless energy. But we still need to do our parts individually, such as by using energy-efficient computers in our research,” says John Wright, a member of MIT’s Plasma Science & Fusion Center (Gizmag and Cycling News).

Posted by Daniel Cressey on December 20, 2007
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And the Nobel goes to Albert Fert of the University of Paris-Sud and Peter Grünberg of the Jülich Research Centre for the discovery of giant magnetoresistance (announcement). It's their second big prize of the year -- they took a share of the Japan Prize this spring (press release)

For updates see the full post.

For coverage of yesterday's Nobel for Physiology or Medicine, awarded to Mario Capecchi, Martin Evans and Oliver Smithies, see this post

Continue reading "Physics Nobel announced" »

Posted by Oliver Morton on October 09, 2007
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Scientists in the UK have made a major step in quantum computing by demonstrating that superconducting electrical circuits can be used to send information between two stores of quantum information (AFP, Reuters). The advance is detailed in two papers in this week's Nature – one by Silanpaa and colleagues and the other by Johannes Majer and colleagues.

Silanpaa and co connected their storage mechanisms for quantum information (qubits) via a cavity in which an electromagnetic wave had been established. Majer and co did a similar thing, but using ‘virtual’ photons (“weak perturbations of their cavity's quantum light field” according to an accompanying News and Views article, subscription required). As if quantum computing wasn’t difficult enough, another paper from last week’s Nature is also relevant, one authored by Houck et al. They detailed a ‘single-photon gun’ that can be used to generate and guide photons in an electrical circuit

What does this all mean though? Basically, for quantum computing to work we need to be able to transfer information stored in qubits to other qubits. Previously this had only been done between qubits that were (relatively) close to each other; this work shows it can be done over (relatively) large distances. Here’s what the News and Views piece makes of it all: “these papers represent confident steps towards the ultimate goal of a viable, large-scale quantum computer.”.

Yale, where many of these researchers are based, has a press release on this too.

Image: “coplanar waveguide cavity connecting two superconducting phase qubits at each end” / Michael Kemper

Posted by Daniel Cressey on September 27, 2007
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The ‘true nature’ of dark matter could be revealed by new computer modelling work (BBC). The modelling, published in Science, suggests in a universe dominated by “warm” dark matter the first stars could have formed from fragments of filaments thousands of light-years long (study abstract, commentary). “The filaments would have been about 9,000 light years long, which is about a quarter the size of the Milky Way galaxy,” according to study leader Liang Gao of Durham University in the UK (press release 1, press release 2). “They would have fragmented in a huge burst of star formation, a spectacular event to contemplate.”

“What is new is we were first to show the properties of these first stars depended so crucially on dark matter,” co-author Tom Theuns, also at Durham, told Reuters. When simulations were run with cold dark matter – the particles of which are less energetic than their warmer brethren – the first stars formed in bunches, rather than in strings. This difference is important as observations could tell us which of the two scenarios is actually true. “If the first constellations can be mapped by future telescopes, the energy of the underlying dark matter may be deduced simply by reading the stars, telling us what dark matter is potentially made of,” says Joanna Baker, associate editor at Science magazine, in AFP’s coverage of the study.

Some of these stars could even be around today – larger stars have shorter life spans but the warm dark matter model predicts that some low mass stars would also be formed. These would still be, as Theuns puts it, “lurking in our galaxy”.

Image: / Science

Posted by Daniel Cressey on September 17, 2007
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A giant X-ray machine in Oxfordshire is going to peer inside unopened manuscripts too fragile to unfurl. Tim Wess from the University of Cardiff has worked out that X-rays from the Diamond synchrotron can be used to image the writing on ancient parchments. Now he wants to look at some of the Dead Sea Scrolls that have so far been deemed too brittle to read, he told the British Association Festival of Science in York (covered by the Daily Telegraph, Times, Daily Mail, Guardian, and the BA). “We’ve folded up a real piece of parchment and then done a process of X-ray tomography on it. We’ve been able to recover the structure where we can see the words that are written inside the document,” says Wess (BBC).

Collagen in animal skins used to write on turns to gelatine when wet, making the documents sticky and hard to read. Drying makes them brittle and equally, if differently, problematic. But iron in the ink used shows up on X-rays and, using computers, different layers of folded or rolled documents can be read. Wess is currently perfecting his technique on documents less valuable than the Dead Sea Scrolls and he believes in three or four years it will be good enough to read text in pamphlets and thin books. Unread works by Beethoven and Mozart would then be accessible (The Daily Telegraph, Times). So far his team has been able to read 80% of the text from 18th century legal documents they have been studying (Guardian).

This is actually the latest development in a great tradition of using X-rays to analyse valuable artefacts. They have previously peered under the surface of paintings to detect images hidden beneath, helped date and conserve sculptures and even detected fraud.

Image: unrolled parchment X-ray / Cardiff University

Posted by Daniel Cressey on September 13, 2007
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A little mix-up over at the Minot Air Force Base in North Dakota gets a lot of ink today. Last week, a ground crew accidentally loaded six nuclear-tipped cruise missiles onto a B-52 bomber bound for Louisiana. The plane arrived without incident, but as of this morning, a munitions commander was relieved of duty and several others had been suspended.

Several papers including the Edmonton Sun, Detroit News, and New York Daily News warned of the Air Force accidentally flying “live” warheads, but it’s pretty unlikely that was the case. The bomber was carrying W-80-1 warheads, which are some of the Pentagon’s more sophisticated weapons. They’re equipped with Permissive Action Links (PALs) which prevent the crew from using them without presidential authorisation. The PALs on these particular warheads maintain an actual physical barrier between the electrical systems of the warhead and the rest of the missile and could even be used to remotely disable it, so there’s no way the crew could have armed, fused or fired the missiles. Even if the plane had crashed, the warhead’s “primary” contained fire-resistant “insensitive” high explosives of the type that would be unlikely to detonate.

In fact things were a lot more dangerous in the good old days of the Cold War. In the early 60s, the Air Force kept nuclear-armed B-52s aloft twenty-four-seven. The programme came to an end in 1968 after one of the B-52s carrying four nukes crashed in Thule, Greenland. A succinct summary of the incident, and the Air Force’s nuke-flying history can be found here

The real issue here, as most of the coverage pointed out, is the inventory system the Air Force uses to keep track of its weapons. It should be quite difficult for a ground crew to load warheads in place of duds, and a thorough investigation will be needed to find out exactly what happened.

Credit: USAF

Posted by Geoff Brumfiel on September 06, 2007
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Cries of “mine’s bigger than yours” will surely have been flying from US neutron physicists to their UK counterparts at the end of last week. For America has smashed the previous record for neutron source beam power. Basically this means that they have a more powerful device to smash neutrons out of a target and use these neutron to study materials. More importantly they have bragging rights (press release).

“If this is your field, if this is what you want to do, then this is where you want to be. There is no place in the world that can do what we can do with high performance computing, neutron, and with nano-science,” said Tom Mason, director of the Oak Ridge National Laboratory where the new-record holding neutron source is located (WATE).

The lab’s $1.4 billion Spallation Neutron Source works by throwing negatively charged hydrogen through foil, stripping the hydrogen electrons and thereby turning it into protons. Bunches of these protons are then hurled at liquid mercury, where they free up neutrons which can be guided in beam lines and used in experiments. Nature looked at the machine in detail back in 2005 (subscription required).

As AP points out, there is something of an arms race going on. The Oak Ridge neutron beam has reached 183 kilowatts, beating the UK record of 160. However the UK is going to double its capacity. But wait! The Oak Ridge machine isn’t even out of second gear yet and will eventually produce 10 times more neutrons than it is now.

"I like to be first. Tennesseans like to be first. ... My grandfather used to say aim for the top--there is more room there. What we see are some firsts,” said local senator Lamar Alexander (WBIR). The Great Beyond thinks a verse of one of the state songs is in order: “TENNE-, TENNE-, TENNES-SEE! Oh, how proud we are of thee!”

Posted by Daniel Cressey on September 03, 2007
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In ten years we will all be able to don suits giving us Spiderman like abilities, according to The Times. Unfortunately the new research from Nicola Pugno which The Times and others are reporting only shows theoretically that it could be done and rounds up previous research. We still don’t actually have even a prototype suit so ten years seems pretty ambitious to me.

Pugno, from the Polytechnic of Turin in Italy, has published an article in the Journal of Physics suggesting carbon nanotubes could be used to develop microscopic Velcro that could lead to human sticky suits. “However now that we are this step closer, it may not be long before we are seeing people climbing up the Empire State Building with nothing but sticky shoes and gloves to support them,” he says in the press release (a comment picked up with enthusiasm by UK tabloids The Sun and the Mirror). As the BBC notes, “Professor Pugno also outlined three properties which a real Spider-man suit must demonstrate. Firstly, and most obviously, it must be able to demonstrate strong adhesive properties. Secondly, the suit must be able to detach easily from a surface after it has stuck. Thirdly, the suit must, to some degree, be able to clean itself.”

Commenting on the story to Wired Ronald Fearing, an electrical engineering professor at the University of California at Berkeley, said: “We already know that if you take the performance of the gecko and scale it up to a person, you'd be all set," he said. "We don't know all the details of how the gecko works, however.” Scientists have been working on similar projects for years of course, but Pugno has pulled the various strands together in one article.

Of course, once you’ve gained super hero powers, you still have to put up with the same social problems – as Philip Ball explains in a recent Nature Muse.

Posted by Daniel Cressey on August 29, 2007
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