It is spring and we went to check out the migratory birds returning from their winter grounds. It is pretty incredible to think that some of them have crossed deserts and oceans on their journeys, and they still manage to find their way back to the same locations every year.
For example, did you know that the Arctic Tern is the World Record holder when it comes to migration amongst birds? It spends Northern Hemisphere summers in the Arctic and then for winter it flies all the way to the Antarctic! Absolutely crazy to think that in one year it has seen more of the world than most of us will in a lifetime. In this week’s video we take a look at the physics behind a few of the adaptations that the birds have evolved to be able to perform these annual migrations. Enjoy!
Produced by: Jonas Stenstrom
Filming help by: Louise Fornander & John-Mehdi Ghaddas
The Neural Basis of Long-Distance Navigation in Birds
Abstract
Migratory birds can navigate over tens of thousands of kilometers with an accuracy unobtainable for human navigators. To do so, they use their brains. In this review, we address how birds sense navigation- and orientation-relevant cues and where in their brains each individual cue is processed. When little is currently known, we make educated predictions as to which brain regions could be involved.
We ask where and how multisensory navigational information is integrated and suggest that the hippocampus could interact with structures that represent maps and compass information to compute and constantly control navigational goals and directions. We also suggest that the caudolateral nidopallium could be involved in weighing conflicting pieces of information against each other, making decisions, and helping the animal respond to unexpected situations. Considering the gaps in current knowledge, some of our suggestions may be wrong. However, our main aim is to stimulate further research in this fascinating field. Expected final online publication date for the Annual Review of Physiology Volume 78 is February 10, 2016. Please see http://www.annualreviews.org/catalog/pubdates.aspx for revised estimates.
This trailer kicked off the official United Nations/UNESCO opening ceremony of the IYL2015 in Paris on January 19, 2015.
The concept of this video ‘propagated light from the cosmos activating life on earth’, is based on Barris’ documentary filmEinstein’s Light, which is in production and will be released in September 2015.
For the first time, physicists from the Kavli Institute of Nanoscience at the Delft University of Technology in the Netherlands have reportedly been able to teleport information between a pair of quantum bits that are about ten feet apart. The ability to do this pokes a hole in Einstein’s theory about entanglement or connection of particles that are light years apart, and how the state of a particle instantly affects the state of another particle.
For the first time with 100 percent accuracy, physicists from the Kavli Institute of Nanoscience Delft, at the Delft University of Technology in the Netherlands have reportedly been able to teleport information between a pair of quantum bits that are about ten feet apart.
The ability to do this pokes a hole in Einstein’s disbelief in entanglement where particles remain connected with the state of one particle instantly affecting the state of another despite being light years apart.
There are several groups of scientists working on similar projects, and the Dutch researchers have been able to reliably teleport the information by trapping electrons in diamonds at extremely low temperatures, and observing their electron spins.
Ronald Hanson, a physicist who leads the group at Delft University of Technology is quoted as saying: “There is a big race going on between five or six groups to prove Einstein wrong. There is one very big fish.”
Now that they have been able to repeatedly teleport the information from ten feet away, the researchers want to see if they can send the information between even further distances.
This development might make it possible to have a faster generation of computer systems that also operate on completely secure communication networks.
One of the weirdest bits of physics is proved beyond doubt (almost)
Oct 24th 2015
IN THE 1930s Albert Einstein was greatly troubled by a phenomenon that emerged from quantum theory. Entanglement, as it is called, forever intertwines the fates of objects such as subatomic particles, regardless of their separation. If you measure, say, “up” for the spin of one photon from an entangled pair, the theory suggests that the spin of the other, measured an instant later, will surely be “down”—even if the two are on opposite sides of the galaxy. This was anathema to Einstein and others: it looked as if information was travelling faster than light, a no-no in the special theory of relativity. Einstein was quotably derisive, calling the idea “spooky action at a distance”. But after 80 years of physicists’ fretting, a cunning experiment reported this week proves that such action is in fact how the world works.
To save physics from the spooky, Einstein invoked what he called hidden variables (though others might describe them as fiddle factors) that would convey information without breaking the universal speed limit. It took until 1964, though, to tame this woolly idea into testable equations. John Bell, a British physicist, worked out the maximum effect hidden variables could have on a given test. Any influence beyond that, his equations suggested, must be down to spooky action. The Bell inequality, as it became known, sparked decades of clever experiments—sending entangled photons or atoms hither and thither with detectors triggered by this or that—each designed to catch nature out, to banish hidden variables once and for all.
Yet a number of loopholes remained—ways that hidden variables might exert some influence, though the purported mechanisms became increasingly contrived as years and experimental finesse advanced. One was the detection loophole. Reliably catching a single photon, for example, is tricky; lots of them go amiss in a given experiment. But if an experiment does not capture all of its participants, the loophole idea goes, perhaps hidden variables convey information through the missing ones. Another was the communication loophole. If the two measurements happen near enough to one another, some invisible hidden-variable signal might be passing between them (as long as that signal does not go faster than light).
Plenty of experiments have closed one or the other of these loopholes, for example by detecting particles that are more reliably caught than photons, or by sending photons so far apart that no slower-than-light signal could flit between them in time to have an effect. By now, most physicists reckon the hidden-variable idea is flawed. But no test had closed both loopholes simultaneously—until this week, that is.
Ronald Hanson of the University of Delft and his colleagues, writing in Nature, describe an experiment that starts with two electrons in laboratories separated by more than a kilometre. Each emits a photon that travels down a fibre to a third lab, where the two photons are entangled. That, in turn, entangles the electrons that generated the photons. The consequence is easily measured particles (the electrons) separated by a distance that precludes any shifty hidden-variable signalling.
Over 18 days, the team measured how correlated the electron measurements were. Perhaps expectedly, yet also oddly, they were far more so than chance would allow—proving quantum mechanics is as weird as Einstein had feared.
Though this experiment marks an end to hidden variables, Dr Hanson says it is also a beginning: that of unassailably secure, quantum-enabled cryptography. It was shown in 1991 that the very Bell tests used to probe hidden variables could also serve as a check on quantum cryptography. A loophole-free Bell test, then, could unfailingly reveal if a hacker had interfered with the fundamentally random, quantum business of generating a cryptographic key. So-called device-independent quantum ciphers would, Dr Hanson says, be secure from hackers “even if you don’t trust your own equipment—even if it’s been given to you by the NSA”.
There remains, alas, one hitch that could explain all these counterintuitive findings. Just maybe, every single event that will ever be, from experimenters’ choices of the means of measurement to the choice of article you will read next, were all predetermined at the universe’s birth, and all these experiments are playing out just as predetermined. That, however, is one for the metaphysicists.
Nobel Prize-winning physicist Albert Einstein is well known for his contributions to science, but not so publicized are his efforts to speak out against racism in the United States, as evidenced by papers written by Einstein recently made public. Ze’ev Rosenkranz, assistant director and senior editor of the Einstein Papers Project at the California Institute of Technology, joins Arise America to discuss this little known side of Einstein.
The immortal physicist, moral philosopher and fervent violinist was so disturbed by the state of racial relations in his American homeland that in 1946 he published an agonised denunciation of ‘this deeply entrenched evil.’
The [American] sense of equality and human dignity is mainly limited to men of white skins. Even among these there are prejudices of which I as a Jew am clearly conscious; but they are unimportant in comparison with the attitude of the “Whites” toward their fellow-citizens of darker complexion, particularly toward Negroes. The more I feel an American, the more this situation pains me. I can escape the feeling of complicity in it only by speaking out.
What, however, can the man of good will do to combat this deeply rooted prejudice? He must have the courage to set an example by word and deed, and must watch lest his children become influenced by this racial bias.
A schoolboy doing work experience with an astrophysics professor has discovered a new planet 1,000 light years from Earth.
Newcastle-under-Lyme school pupil Tom Wagg was 15 when he went for his work placement at Keele University, where he spotted a minuscule dip in the light from a faraway star that he knew could be caused by a planet passing in front of it.
Wagg kept in touch with the university’s Prof Coel Hellier while the potential planet was analysed by scientists from the universities of Geneva and Liege.
Two years later, the 17-year-old got the call confirming his discovery was indeed a new planet – a large gas planet with similar properties to Jupiter in the southern constellation of Hydra. Its characteristics mean it is very unlikely to support any form of life.
Although credited with the discovery, Wagg has not been allowed to name the planet he discovered, which will be decided by competition entries co-ordinated by the International Astronomical Union.
The new planet has been temporarily termed WASP-142b, because it is 142nd discovery by the Wide Angle Search for Planets (WASP) project, whose data Wagg had been searching through.
“I had no idea what kind of work I’d be doing on the placement, let alone what I’d discover,” Wagg said. “When I realised what it could be I was astonished, it’s been a real boost to me to carry on with science.”
Hellier said he had been impressed by his “bright” work experience pupil and said that good observation skills had been key to spotting the small dip which revealed the planet’s existence.
“Humans are far better at doing this than a computer algorithm,” he said. “It’s not that rare to discover a planet – we’ve probably discovered 1000 in the last 10 years – but I’m not aware of any others being discovered on work experience.”
Wagg admitted he was a little sad he would not necessarily have the planet named after him. “In a way I am sad, but I definitely didn’t expect it to be, I understand why it’s a competition,” he said. “I do hope it encourages other people to know that anyone can find a planet, if they get access to the data and they know what to look for.”
Wagg, who is studying physics, maths, further maths and latin for A-level next year, plans to continue with physics at university. But he has not quite decided whether he will be pursing planets.
“I’m torn between particle physics and astrophysics, which seem on the face of it pretty different because one deals with the smallest things in the universe, and the other with the biggest,” the young scientist said.
“But actually, there are real similarities because if you study one, you can understand both, because the laws of physics apply to everything. That’s the beauty of science.”
This is a video about a 2008 exhibition in the Lakenhal and Boerhaave museums in Leiden, the Netherlands about the Kamerlingh Onnes family. Some people in that family were physicists (with a special interest in cold temperatures), some were visual artists.
Leiden artist Harm Kamerlingh Onnes (1893-1985) has portrayed twenty renowned scholars in the years when they visited his uncle, the Nobel Prize winner Heike Kamerlingh Onnes. Among them was Albert Einstein. Boerhaave Museum in Leiden has now acquired these sketches and drawings. The majority was not known until now.
Harm was in 1920 and 1921 also regularly found in the laboratory of his uncle Heike, who was doing research on absolute zero temperature (-273 ° C). He made portraits and recorded how his uncle and staff were busy with their experiments.
Houseguests
The physicist Heike Kamerlingh Onnes received the Nobel Prize in 1913. In his Leiden home, Huize ter Wetering at the Galgewater, at that time many foreign guests visited.
The collection of drawings is from the estate of a son of Harm Kamerlingh Onnes. A selection will be on show from 21 February until 26 April at the Museum Boerhaave in Leiden. About the family of scientists and artists an accompanying booklet has been published with the title Koude, kunst, Kamerlingh Onnes [Cold, art, Kamerlingh Onnes], written by Dirk van Delft.
CND vice-president puts former university in the spotlight
BRISTOL University came under fire for its nuclear weapons work yesterday from a former student turned UN arms adviser.
Dr Rebecca Johnson called on the institution to drop millions of pounds worth of “corrupt funding” it is receiving for carrying out research for the Atomic Weapons Establishment.
The CND vice-president quit a physics course at Bristol University after discovering it was working with the atomic weapons factory at Aldermaston.
And Dr Johnson, who later graduated from the university with a degree in politics, said she was “outraged” to discover bosses are now taking even bigger sums from the bomb makers.
“I pulled out of my course after finding that the Bristol physics department was hand-in-glove with the atomic weapons makers at Aldermaston, and I’m outraged that this immoral collaboration is still continuing,” she said.
“As a Bristol alumnus, I urge the university to reject this corrupt funding for nuclear weapons research and proliferation.”
Dr Johnson issued her call to end weapons research on campus in a lecture at the neighbouring University of the West of England.
Her speech is likely to embarrass bosses at her former university given her extraordinary journey from activist to top-level adviser since she graduated in 1977.
But the academic went on to become a senior adviser to former UN weapons inspector Hans Blix on the International WMD Commission that he chaired in 2006.
And she added: “Research that contributes to the replacement of Trident is an egregious violation of the UK’s binding international treaty obligations to eliminate nuclear weapons.
“The only legally justifiable research is in verifying nuclear disarmament and ensuring that existing weapons are safely and securely dismantled and eliminated.”
Ex-nuclear scientist and local campaigner Dr Rowland Dye added: “It’s shocking that the government is still squandering our taxpayers’ money on nuclear weapons, and that Bristol is colluding in Trident replacement, contrary to our international legal obligations.”
The Star twice contacted Bristol University for a response without reply.
The most detailed aerodynamic simulation of hummingbird flight conducted to date demonstrates that it achieves its aerobatic abilities through a unique set of aerodynamic forces more closely aligned to those found in flying insects than in other birds. The simulation was produced by Vanderbilt engineers working with a biologist from the University of North Carolina at Chapel Hill.
Just how tiny hummingbird[s] can hover in front of a flower before darting to another has always puzzled scientists.
But new research shows that this ability is more closely related to those found in flying insects than to other birds.
A three-dimensional aerodynamic simulation demonstrated that the tiny birds make use of unsteady airflow mechanisms to generate invisible vortices of air that produce the lift they need to hover and flit from flower to flower.
When a bird pulls its wings forward and down, tiny vortices form over the leading and trailing edges and then merge into a single large vortex, forming a low-pressure area that provides lift. The tiny hummingbird[s] further enhance the amount of lift they produce by pitching up their wings (rotate them along the long axis) as they flap.
However, unlike most birds, hummingbirds are also able to generate lift on the upstroke by inverting their wings. As the leading edge begins moving backwards, the wing beneath it rotates around so the top of the wing becomes the bottom and bottom becomes the top. This allows the wing to form a leading edge vortex as it moves backward generating positive lift.
Although hummingbirds are much larger than flying insects and stir up the air more violently as they move, the way that they fly is more closely related to insects than it is to other birds, according to the researchers. Insects like dragonflies, houseflies and mosquitoes can also hover and dart forward and back and side to side.
The new realistic simulation (see film above) demonstrates that the tiny birds make use of unsteady airflow mechanisms, generating invisible vortices of air that produce the lift they need to hover and flit from flower to flower.
According to Henk van der Jeugd of the Dutch Institute of Ecology (NIOO-KNAW) in Wageningen there is still too little known to draw conclusions. “Migratory birds are an easy scapegoat,” he says. “If migratory birds brought the virus, then we would have to find it in wild birds in the vicinity of the affected captive bird business.” But that has not been done yet.
He thinks the facts should be investigated thoroughly. “Otherwise no effective measures can be taken.” …
Because migratory birds were designated as disseminators of the virus, according to Van der Jeugd other possibilities were neglected. For example, migratory birds may become infected by native birds, instead of the other way round.
Last month a NIOO study about ducks in the Netherlands showed that migratory wild mallards here get a mild form of bird flu from native ducks, which have the virus, but do not themselves become ill.
This bio-film is based on Bertold Brecht‘s play about Galileo Galilei, the 17th century Italian who laid the foundations of modern science. Galileo made himself one of the world’s first telescopes and discovered the moons of Jupiter.
He supported Copernicus’ theory that the Earth revolved around the Sun. This brought him in conflict with the Catholic Church. By threatening him with torture, the Church forced him to recant his views in front of a tribunal, and sentenced him to house arrest. However, Galileo’s trials and theories inspired others like Newton and Kepler to prove that the Earth was not the centre of the Universe. Some years ago, the Pope accepted that Earth does revolve around the Sun and issued a rare apology for what the Church had done to Galileo, i.e., the Catholic Church recanted.
Renaissance Genius: Galileo Galilei and His Legacy to Modern Science, David Whitehouse, Sterling, 2009 (US $24.95)
This volume is a welcome contribution to the study of the Italian Renaissance, written by the British archeologist David Whitehouse. It gives a comprehensive view of the world of the Italian Renaissance at a time when ideas, discoveries and new inventions accelerated the clash of science with the medieval institution of the Roman Catholic Church. The book’s primary focus is the life and work of Galileo Galilei (1564-1642), whose persecution by the Church reflects the tribulations of most of the progressive thinkers of the time.
The book was published to coincide with the 400th anniversary of the year when Galileo turned his significantly improved version of the telescope to the night skies and began to draw the phases of the moon. It is lavishly illustrated with paintings, photographs, and illustrations that depict the time in which Galileo lived, his life, friends, colleagues, adversaries and persecutors.
As Renaissance Genius shows, this was the time of the Inquisition and its imprisonment, torture, and heinous executions of those deemed “heretics.” This included anyone who challenged existing church doctrine, particularly those developing the new techniques of observation, experimentation and the combination of the two with mathematics. Among those persecuted were Giordano Bruno, Antonio de Dominis and Galileo himself.
Vincenzo Galilei, Galileo‘s father, was a mathematician and music theorist who challenged traditional beliefs in the infallibility of Greek philosophic thought backed by both church and state. He found, for example, that the practical application of experimentation disproved long-held beliefs of the ancient Greek philosopher Pythagoras on musical interval and pitch between two strings. Pythagoras had held that in the tuning of strings, the weights used to stretch the strings, the tension must be doubled. It turned out that in practice, the tension had to be quadrupled, not doubled, to produce a tone an octave higher. As Whitehouse explains:
“It is hard to underestimate the importance of this moment in Galileo’s life. He and his father had found a new harmony; a new set of mathematical laws that correlated the note produced by a string to its tension, and had done so by experiment. They had not looked up the answer in either an ancient Greek treatise nor sought the advice of some musical authority. This was the start of modern science: They had carried out an experiment and asked a question of nature itself. It was revolutionary. Vincenzo’s actions had unfolded the course of his son’s life in experimental physics.”
Later in life, Galileo would use experimental techniques to show that objects fall towards the Earth at the same rate, regardless of mass. That some objects seem to fall slower is because of air resistance, not a property of the objects themselves. This challenged the Aristotelian principle that claimed that heavier objects fall faster than lighter ones. The most famous of these experiments was done at the Leaning Tower of Pisa, when he released two identically shaped spheres of different masses from the top of the tower. The spheres, one of 100 pounds and the other only one pound, hit the ground at the same time.
Nearly 400 years later, astronaut David Scott of Apollo 15, carried out a similar experiment on the surface of the moon, releasing a feather and a metal hammer. Both struck the lunar surface at the same time. “Galileo was correct,” exclaimed Scott.
This video is called APOLLO 15 Hammer and Feather.
Galileo’s achievements also involve a number of inventions related to other fields of science. He developed the thermoscope, the predecessor of the thermometer, which was the first attempt to measure heat. The Venetian Senate awarded him a patent for a water-lifting machine used in irrigation that only used one horse. A friend in the tool-making trades helped Galileo develop a simple compass that could be used to gauge the distance and height of a target as well as measure the angle of elevation of a cannon’s barrel. While Galileo did not invent the telescope, which was first built in the Netherlands in 1608, he is credited with increasing the magnification by 20 to 30 times using advanced lens-crafting techniques.
His interest in telescopes was sparked in 1604 when a new “star” appeared in the constellation Ophiuchus. This followed an earlier appearance of a new star in 1572 that was studied by the Danish astronomer Tycho Brahe. Such occurrences challenged the long-held notion of both the Aristotelians and the Church that the heavens are perfect and unchanging. Always being one to pursue observations, Galileo sought a way to study the night sky in greater detail.
With his telescope, he began to paint the different phases of the moon and its observable dark and light spots. He showed the moon to his patron, the Duke of Tuscany, who was delighted. Galileo then observed the Pleiades star cluster, as well as the planet Jupiter. Through these observations, he discovered the four largest moons of Jupiter – Io, Callisto, Europa and Ganymede, and provided the first evidence of objects orbiting a body other than the Earth. This was the proof Galileo needed to become a fervent advocate of the Copernican model of the cosmos.
A similar realization was made during Galileo’s study of the phases of Venus, repeating in much greater detail observations done by Copernicus. After recording the pattern of sunlight reflected from Venus’ atmosphere, he realized that the only way such patterns could occur is if both Venus and Earth revolved around the Sun. Galileo published a book on his observations, which circulated throughout Europe.
Included in his observations were the recording of sunspots. By aiming the telescope at the Sun and letting the light pass through the telescope onto a white background, Galileo was able to sketch out the positions of sunspots and determine that such imperfections on the Sun both existed and changed with time. Both this observation and the experimental evidence that the Earth is not the center of the universe incurred the wrath of the Church.
Both the Greek philosopher Aristotle and the Vatican considered the sun a perfect and unblemished sphere. The stars themselves were seen as divinities, contributing to the growth of astrology. It was argued by church supporters that the observed sunspots must be satellites of the sun and not “imperfections” in its surface. Galileo stated that not only were sunspots on the surface of the sun, they changed their shapes, and both originated and dissolved on that sphere. This could only lead to one conclusion: the sun was not a perfect sphere.
Galileo’s popularity and a newly established science academy in Rome ensured the continued publication of his works and a certain defense against the Church and other professional enemies. However, the issue of sunspots became the spark for an open clerical attack upon Galileo.
The story of how this debate unfolded is but one example of how the church and its privileged office-holders used the Bible to defame scientists like Galileo. Galileo himself believed that nothing that was discovered in any way conflicted with Scripture and quoted an ecclesiastical historian, Cardinal Baronius (1538-1607), who had commented: “The Holy Ghost intended to teach us how to go to heaven, not how the heavens go.” This clever riposte did not save him. As Whitehouse points out:
“In his innate conservatism, Cardinal Bellarmine saw the Copernican universe as threatening to the social order. To him and to much of the Church’s upper echelon, the science of the matter was beyond their understanding — and in many cases their interest. They cared more for the administration and the preservation of Papal power than they did for getting astronomical facts right.”
In the end, Galileo was told by Bellarmine and the head of the Inquisition, Cardinal Agostino Oreggi, that Copernicus’ views were wrong and he was not to support them. Furthermore, he was ordered not to teach or defend Copernican theory in any way, either in his writings or verbally.
After Bellarmine and Pope Paul V died, Galileo still harbored great hopes that the new Pope, Urban VIII, his former friend Maffeo Barberini, would prove when elected to be much better than his predecessors. This was an illusion. He was summoned before an even more hostile Inquisition than the first time.
While Whitehouse speculates that for Barberini, being Pope “had gone to his head,” the more fundamental truth is, as he observed earlier, that the Church hierarchy as a whole viewed “the Copernican universe as threatening to the social order.” The Pope, no matter his individual origins, was bound by his place in medieval society to defend the status quo.
The reproductions in Whitehouse’s book of paintings and illustrations depicting book burnings, the burnings at the stake for heresy, and the humiliations endured by thousands at the hands of the Inquisition reinforce this point.
Renaissance Genius depicts how Galileo’s defense of the Copernican system and the subsequent discoveries by Kepler, Rene Descartes, and Isaac Newton not only established the beginnings of physics, but also led to the advances for science that have resulted in the modern space program, including the space probe named after Galileo and the Hubble space telescope, the most extraordinary advance in the technology which Galileo pioneered.
Whitehouse sums up the Galilean revolution by providing us with a very human portrait of the man, the history of his times and Galileo’s indispensable role in the advancement and popularization of science for humankind.
Dear Kitty. Some blog 