Science

Men with brown eyes have more trustworthy faces than men with blue eyes, according to a new study that proposes sexual selection of women in Europe about 10,000 years ago could be the cause.

Various facial traits, such as larger noses and higher set features, have previously been associated with perceived traits such as trustworthiness, dominance and attractiveness, which in turn can indicate political success or salary of the person. But this was the first study that looked at eye colour and perceptions of trustworthiness.

Men with brown eyes tend to be perceived as more trustworthy than men with blue eyes, concluded Karel Kleisner, from Charles University in Prague, Czech Republic, co-author of the story published in the journal PLOS One — via redwolf.newsvine.com

Australia’s giant and record heatwave, which is sparking hundreds of bush fires across the land, has forced the country’s meteorologists to redraw their national temperature scales — upwards.

In an unprecedented move, the Australian Bureau of Meteorology has extended the temperature range on its charts from the previous cap of 50 degrees Centigrade — 122 degrees Fahrenheit — to 54 degrees C, which is more than 129 degrees in Fahrenheit terms.

At the same time, it has added two entirely new colours — deep purple and pink — to show the new extreme range on its interactive weather maps. A patch of purple, indicating 50+, is now visible on one of the temperature charts for next week.

This is thought to be the first time that any country in the world has actually redrawn its charts to take account of temperatures which are thought likely to go off the scale which had been previously applied, and climate scientists indicated it was a warning for the future — via redwolf.newsvine.com

It may sound less likely than hell freezing over, but physicists have created an atomic gas with a sub-absolute-zero temperature for the first time. Their technique opens the door to generating negative-Kelvin materials and new quantum devices, and it could even help to solve a cosmological mystery.

Lord Kelvin defined the absolute temperature scale in the mid-1800s in such a way that nothing could be colder than absolute zero. Physicists later realized that the absolute temperature of a gas is related to the average energy of its particles. Absolute zero corresponds to the theoretical state in which particles have no energy at all, and higher temperatures correspond to higher average energies.

However, by the 1950s, physicists working with more exotic systems began to realise that this isn’t always true: Technically, you read off the temperature of a system from a graph that plots the probabilities of its particles being found with certain energies. Normally, most particles have average or near-average energies, with only a few particles zipping around at higher energies. In theory, if the situation is reversed, with more particles having higher, rather than lower, energies, the plot would flip over and the sign of the temperature would change from a positive to a negative absolute temperature, explains Ulrich Schneider, a physicist at the Ludwig Maximilian University in Munich, Germany — via redwolf.newsvine.com

Following up on earlier theoretical predictions, MIT researchers have now demonstrated experimentally the existence of a fundamentally new kind of magnetic behaviour, adding to the two previously known states of magnetism.

Ferromagnetism — the simple magnetism of a bar magnet or compass needle — has been known for centuries. In a second type of magnetism, antiferromagnetism, the magnetic fields of the ions within a metal or alloy cancel each other out. In both cases, the materials become magnetic only when cooled below a certain critical temperature. The prediction and discovery of antiferromagnetism — the basis for the read heads in today’s computer hard disks — won Nobel Prizes in physics for Louis Neel in 1970 and for MIT professor emeritus Clifford Shull in 1994.

We’re showing that there is a third fundamental state for magnetism, says MIT professor of physics Young Lee. The experimental work showing the existence of this new state, called a quantum spin liquid (QSL), is reported this week in the journal Nature, with Lee as the senior author and Tianheng Han, who earned his PhD in physics at MIT earlier this year, as lead author.

The QSL is a solid crystal, but its magnetic state is described as liquid: Unlike the other two kinds of magnetism, the magnetic orientations of the individual particles within it fluctuate constantly, resembling the constant motion of molecules within a true liquid — via redwolf.newsvine.com

New linguistic research has concluded that residents of the British Isles didn’t just borrow words and expressions from Norwegian and Danish Vikings and their descendants. Rather, claim two professors now working in Oslo, the English language is in fact Scandinavian.

Jan Terje Faarlund, a professor of linguistics at the University of Oslo (UiO), told research magazine Apollon that new studies show English as we know it today to be a direct descendant of the language Scandinavians used after settling on the British Isles during and after the Viking Age. An article by Apollon’s editor Trine Nickelsen was published in Norwegian newspaper Aftenposten on Tuesday — via redwolf.newsvine.com

With a homicide rate historically more than three times greater than the rest of the United States, Newark, New Jersey, isn’t a great vacation spot. But it’s a great place for a murder study.

Led by April Zeoli, an assistant professor of criminal justice, a group of researchers at Michigan State University tracked homicides around Newark from 1982 to 2008, using analytic software typically used by medical researchers to track the spread of diseases. They found that homicide clusters in Newark, as researchers called them, spread and move throughout a city much the same way diseases do. Murders, in other words, did not surface randomly — they began in the city centre and moved in diffusion-like processes across the city.

The study also found that the there were areas of Newark that, despite being beset by violence on all sides, remained almost completely immune to the surrounding trends over the entire course of the 26 years studied. Despite the longitudinal nature of the study, Zeoli notes in a press release that the analytic software can be employed in real time, so that police might potentially identify problem areas as they are emerging—or perhaps, one imagines, before they emerge. The research is due to be published in a forthcoming issue of a journal called Justice Quarterly — via redwolf.newsvine.com