As the “Brains Vs. Artificial Intelligence: Upping the Ante” poker competition nears its halfway point, Carnegie Mellon University’s AI program, called Libratus, is opening a lead over its human opponents — four of the world’s best professional poker players. Libratus had amassed a lead of $459,154 in chips in the 49,240 hands played by the end of Day Nine. (from cmu.edu)

One of the pros, Jimmy Chou, said he and his colleagues initially underestimated Libratus, but have come to regard it as one tough player. “The bot gets better and better every day,” Chou said. “It’s like a tougher version of us.”

Cosmic rays may have just unveiled a hidden chamber within Egypt’s most famous pyramid. An international team led by Kunihiro Morishima at Nagoya University in Japan used muons, the high-energy particles generated when cosmic rays collide with our atmosphere, to explore inside Egypt’s Great Pyramid without moving a stone. (from newscientist.com)

Muons can penetrate deep into rock, and get absorbed at different rates depending on the density of the rock they encounter. By placing muon detectors within and around the pyramid, the team could see how much material the particles passed through.

“If there is more mass, fewer muons get to that detector,” says Christopher Morris at Los Alamos National Laboratory, who uses similar techniques to image the internal structure of nuclear reactors. “When there is less mass, more muons get to the detector.”

By looking at the number of muons that arrived at different locations within the pyramid and the angle at which they were travelling, Morishima and his team mapped out cavities within the ancient structure.

This type of exploration – muon radiography – is perfect for sensitive historical sites as it uses naturally occurring radiation and causes no damage to the structure.

The team mapped the pyramid’s three known chambers – the subterranean chamber, the Queen’s chamber, and the King’s chamber – along with connecting corridors. They also detected a new large void above the Grand Gallery that connects the King and Queen’s chamber. This new void is approximately the same volume as the Grand Gallery. The team believes it’s another oversized tunnel similar in dimensions to the Grand Gallery that is at least 30 metres long.

The team used three different muon detectors, starting with nuclear emulsion film within the Queen’s chamber. Like photographic film is exposed to light to make a photo, the emulsion reacts to muons and makes a record of their paths.

Once their initial findings indicated a potential cavity, they confirmed it by placing an instrument that emits a flash of light when struck by muons within the pyramid. Outside the pyramid, they also used detectors that record muons indirectly when the high-energy particles ionise the gas inside. After several months in position to record muons, all three methods confirmed a void in the same location.

“It’s marvelous,” Morris says, noting that the long exposure times increase the robustness of the results. “What they’ve seen is fairly definitive,” he says, although it will take drilling and cameras to determine if the cavity is a structural chamber, or a void created by a long-forgotten collapse.

A team led by Luis Alvarez first tried using muon radiography to map pyramids in 1970, but they were unable to detect new voids. If confirmed, this would be the first newly rediscovered chamber within the Great Pyramid in more than a century.

“I’d love to be there when they first stick a camera through a drill hole,” Morris admitted. “It’s not every day we discover a chamber in a pyramid.”

Journal reference: Nature, DOI: 10.1038/nature24647

Using a state-of-the-art device for measuring mass, researchers at the National Institute of Standards and Technology (NIST) have made their most precise determination yet of Planck’s constant, an important value in science that will help to redefine the kilogram, the official unit of mass in the SI, or international system of units. (from nist.gov )

The new NIST measurement of Planck’s constant is 6.626069934 x 10⁻³⁴ kg∙m²/s, with an uncertainty of only 13 parts per billion. NIST’s previous measurement, published in 2016, had an uncertainty of 34 parts per billion.

The kilogram is currently defined in terms of the mass of a platinum-iridium artifact stored in France. Scientists want to replace this physical artifact with a more reproducible definition for the kilogram that is based on fundamental constants of nature.

Planck’s constant enables researchers to relate mass to electromagnetic energy. To measure Planck’s constant, NIST uses an instrument known as the Kibble balance, originally called the watt balance. Physicists widely adopted the new name last year to honor the late British physicist Bryan Kibble, who invented the technique more than 40 years ago.

NIST’s Kibble balance uses electromagnetic forces to balance a kilogram mass. The electromagnetic forces are provided by a coil of wire sandwiched between two permanent magnets. The Kibble balance has two modes of operation. In one mode, an electrical current goes through the coil, generating a magnetic field that interacts with the permanent magnetic field and creates an upward force to balance the kilogram mass. In the other mode, the coil is lifted at a constant velocity. This upward motion induces a voltage in the coil that is proportional to the strength of the magnetic field. By measuring the current, the voltage and the coil’s velocity, researchers can calculate the Planck constant, which is proportional to the amount of electromagnetic energy needed to balance a mass.

There are three major reasons for the improvement in the new measurements, said physicist Stephan Schlamminger, leader of the NIST effort.

First, the researchers have much more data. The new result uses 16 months’ worth of measurements, from December 2015 to April 2017. The increase in experimental statistics greatly reduced the uncertainty in their Planck value.

Second, the researchers tested for variations in the magnetic field during both modes of operation and discovered they had been overestimating the impact the coil’s magnetic field was having on the permanent magnetic field. Their subsequent adjustment in their new measurements both increased their value of Planck’s constant and reduced the uncertainty in their measurement.

Finally, the researchers studied in great detail how the velocity of the moving coil affected the voltage. “We varied the speed that we moved the coil through the magnetic field, from 0.5 to 2 millimeters per second,” explained Darine Haddad, lead author of the NIST results.

In a magnetic field, the coil acts like an electric circuit consisting of a capacitor (a circuit element that stores electric charge), a resistor (an element that dissipates electrical energy) and an inductor (an element that stores electrical energy). In a moving coil, these circuit-like elements generate an electrical voltage that changes over time, said Schlamminger. The researchers measured this time-dependent voltage change to account for this effect and reduced the uncertainty in their value.

This new NIST measurement joins a group of other new Planck’s constant measurements from around the world. Another Kibble balance measurement, from the National Research Council of Canada, has an uncertainty of just 9.1 parts per billion. Two other new measurements use the alternative Avogadro technique, which involves counting the number of atoms in a pure silicon sphere.

The new measurements have such low uncertainty that they exceed the international requirements for redefining the kilogram in terms of Planck’s constant.

“There needed to be three experiments with uncertainties below 50 parts per billion, and one below 20 parts per billion,” Schlamminger said. “But we have three below 20 parts per billion.”

All of these new values of the Planck’s constant do not overlap, “but overall they’re in amazingly good agreement,” Schlamminger said, “especially considering that researchers are measuring it with two completely different methods.” These values will be submitted to a group known as CODATA ahead of a July 1 deadline. CODATA will consider all of these measurements in setting a new value for Planck’s constant. The kilogram is slated for redefinition in November 2018, along with other units in the SI.

A microscopic, bag-like marine creature that lived approximately 540 million years ago (Fortunian stage of the Cambrian period) has been identified from microfossils found in Shaanxi Province, China. (from sci-news.com)

The ancient animal, named Saccorhytus coronarius, is the most primitive example of a so-called deuterostome.

The creature is thought to be the common ancestor of a huge range of species, and the earliest step yet discovered on the evolutionary path that eventually led to humans, hundreds of millions of years later.

Forty-five phosphatized specimens of Saccorhytus coronaries were collected from the Kuanchuanpu Formation, Hexi, Xixiang County, Shaanxi Province, central China.

They were analyzed by experts from the University of Cambridge in the UK, the University of Kassel in Germany, Northwest University, China University of Geosciences and Xi’an Shiyou University in China. The research was published in the journal Nature on January 30, 2017.

“To the naked eye, the fossils we studied look like tiny black grains, but under the microscope the level of detail is jaw-dropping. All deuterostomes had a common ancestor, and we think that is what we are looking at here,” said lead co-author Prof. Simon Conway Morris, from the University of Cambridge.

“Our team has notched up some important discoveries in the past, including the earliest fish and a remarkable variety of other early deuterostomes,” added lead co-author Dr. Degan Shu, from Northwest University.

“Saccorhytus coronarius now gives us remarkable insights into the very first stages of the evolution of a group that led to the fish, and ultimately, to us.”

Most other early deuterostome groups are from about 510 to 520 million years ago, when they had already begun to diversify into not just the vertebrates, but the sea squirts, echinoderms and hemichordates.

This level of diversity has made it extremely difficult to work out what an earlier, common ancestor might have looked like.

By isolating the microfossils from the surrounding rock, and then studying them both under an electron microscope and using a CT scan, the paleontologists were able to build up a picture of how Saccorhytus coronarius might have looked and lived.

This revealed features and characteristics consistent with current assumptions about primitive deuterostomes.

Saccorhytus coronarius was about a millimeter in size, and probably lived between grains of sand on the seabed.

Its body was bilaterally symmetrical — a characteristic inherited by many of its descendants, including humans — and was covered with a thin, relatively flexible skin.

“The body is hemi-ellipsoidal, with a maximum length of 1,300 μm, width 800 μm and height 900 μm. Most material is crushed but several specimens confirm original bilateral symmetry,” the authors said.

This in turn suggests that it had some sort of musculature, leading the team to conclude that it could have made contractile movements, and got around by wriggling.

Perhaps its most striking feature, however, was its rather primitive means of eating food and then dispensing with the resulting waste.

The animal had a large mouth, relative to the rest of its body, and probably ate by engulfing food particles, or even other creatures.

A crucial observation are the small conical structures on its body. These may have allowed the water that it swallowed to escape and so were perhaps the evolutionary precursor of the gills we now see in fish.

But the scientists were unable to find any evidence that the creature had an anus.

“If that was the case, then any waste material would simply have been taken out back through the mouth, which from our perspective sounds rather unappealing,” Prof. Conway Morris explained.