A beam of light can only be seen when it hits matter particles and is scattered or reflected by them. In a vacuum, however, it is invisible. Physicists at the University of Bonn have now developed a method that allows laser beams to be visualized even under these conditions. The method makes it easier to perform the ultra-precise laser alignment required to manipulate individual atoms. The researchers have now presented their method in the journal Physical Review Applied.
When individual atoms interact with each other, they often exhibit unusual behavior due to their quantum behavior. These effects can, for instance, be used to construct so-called quantum computers, which can solve certain problems that conventional computers struggle with. For such experiments, however, it is necessary to maneuver individual atoms into exactly the right position. "We do this using laser beams that serve as conveyor belts of light, so to speak," explains Dr. Andrea Alberti, who led the study at the Institute of Applied Physics at the University of Bonn.

Such a conveyor belt of light contains countless pockets, each of which can hold a single atom. These pockets can be moved back and forth at will, allowing an atom to be transported to a specific location in space. If you want to move the atoms in different directions, you usually need many of these conveyor belts. When more atoms are transported to the same location, they can interact with each other. In order for this process to take place under controlled conditions, all pockets of the conveyor belt must have the same shape and depth. "To ensure this homogeneity, the lasers must overlap with micrometer precision," explains Gautam Ramola, the study's lead author.

There are new discoveries to be made, even in the inner solar system. This was highlighted this past week with the announcement of the discovery of tiny asteroid 2021 PH27. The asteroid orbits the Sun in just 113 days, the shortest orbital period for any known asteroid and the second shortest orbital period for any object in the solar system next to the planet Mercury, at 88 days.

The discovery was made by astronomer Scott S. Sheppard (Carnegie Institution for Science) after searching through images taken by Ian Dell'Antonio and Shenming Fu (both Brown University) at evening twilight on August 13, 2021. Subsequent observations with multiple telescopes around the world enabled astronomers to confirm the asteroid's orbit.

The initial discovery observations were made using the Dark Energy Camera (DECam) based at the National Science Foundation's Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO) complex in Chile. Although the primary mission for the Dark Energy Camera is the study of cosmic expansion, the Brown University astronomers agreed to use DECam at the beginning of their observing run to take wide-field images in the fading twilight.

Renowned psychologist Dan Ariely literally wrote the book on dishonesty. Now some are questioning whether the scientist himself is being dishonest.

A landmark study that endorsed a simple way to curb cheating is going to be retracted nearly a decade later after a group of scientists found that it relied on faked data.

According to the 2012 paper, when people signed an honesty declaration at the beginning of a form, rather than the end, they were less likely to lie. A seemingly cheap and effective method to fight fraud, it was adopted by at least one insurance company, tested by government agencies around the world, and taught to corporate executives. It made a splash among academics, who cited it in their own research more than 400 times.

Picture an anthill. What do you see? A small mound of sand and crumbly dirt poking up through the lawn? A tiny hole disappearing into the ground? A few ants scrambling around busily. Not very impressive, right?

But slip beneath the surface and the above-ground simplicity gives way to subterranean complexity. Tunnels dive downward, branching and leading to specialized chambers that serve as home for the colony's queen, as nurseries for its young, as farms for fungus cultivated for food, and as dumps for its trash. These are not just burrows. They are underground cities, some of them home to millions of individuals, reaching as far as 25 feet underground, often lasting for decades.

Massive study finds that genetic markers associated with same-sex encounters might aid reproduction. But some scientists question the conclusions.

To evolutionary biologists, the genetics of homosexuality seems like a paradox. In theory, humans and other animals who are exclusively attracted to others of the same sex should be unlikely to produce many biological children, so any genes that predispose people to homosexuality would rarely be passed on to future generations. Yet same-sex attraction is widespread in humans, and research suggests that it is partly genetic.

In a study of data from hundreds of thousands of people, researchers have now identified genetic patterns that could be associated with homosexual behaviour, and showed how these might also help people to find different-sex mates, and reproduce. The authors say their findings, published on 23 August in Nature Human Behaviour¹, could help to explain why genes that predispose people to homosexuality continue to be passed down. But other scientists question whether these data can provide definitive conclusions.

Evolutionary geneticist Brendan Zietsch at the University of Queensland in Brisbane, Australia, and his colleagues used data from the UK Biobank, the US National Longitudinal Study of Adolescent to Adult Health and the company 23andMe, based in Sunnyvale, California, which sequence genomes and use questionnaires to collect information from their participants. The team analysed the genomes of 477,522 people who said they had had sex at least once with someone of the same sex, then compared these genomes with those of 358,426 people who said they'd only had heterosexual sex. The study looked only at biological sex, not gender, and excluded participants whose gender and sex did not match.

In earlier research, the researchers had found that people who'd had at least one same-sex partner tended to share patterns of small genetic differences scattered throughout the genome². None of these variations seemed to greatly affect sexual behaviour on its own, backing up previous research that has found no sign of a 'gay gene'. But the collection of variants seemed to have a small effect overall, explaining between 8% and 25% of heritability.

Next, the researchers used a computer algorithm to simulate human evolution over 60 generations. They found that the array of genetic variations associated with same-sex behaviour would have eventually disappeared, unless it somehow helped people to survive or reproduce.

Deep in a gold mine on the outskirts of the small Victorian country town of Stawell, several hours' drive to the north-west of Melbourne, a lab is being built to find one of the universe's most elusive substances: dark matter.

The lab, located a kilometre underground, currently looks more like a tennis-court sized cave than a multi-million-dollar operation. That's because the lab - a partnership between the University of Melbourne, ANSTO, Swinburne and more - is still very much a work in progress. But if successful in its quest it could help solve one of the greatest mysteries of astrophysics.

"It's crunch time for us," says University of Melbourne Associate Professor Phillip Urquijo, a particle physicist and a technical coordinator of the dark matter experiment, called SABRE - the Sodium Iodide with Active Background Rejection Experiment.

Most people have NEVER heard of the Beaufort Gyre, a massive wind-driven current in the Arctic Ocean that actually has far more influence over sea ice than anything we can throw into the atmosphere. The Beaufort Gyre has been regulating climate and sea ice formation for millennia. Recently, however, something has changed; it is not something that would create global warming but threatens a new Ice Age.

There is a normal cycle that appears to be about 5.4 years where it reverses direction and spins counter-clockwise, expelling ice and freshwater into the eastern Arctic Ocean and the North Atlantic. The 5.4-year cycle is interesting for it is two pi cycle intervals of 8.6. The immediate cycle has suddenly expanded to two 8.6-year intervals, bringing it to 17.2 years as we head into 2022.

What you must understand is that this Beaufort Gyre now holds as much freshwater as all of the Great Lakes combined. Why is that important? Saltwater freezes at a lower temperature than the 32 degrees F at which freshwater freezes. The difference between the air temperature and the freezing point of saltwater is bigger than the difference between the air temperature and the freezing point of fresh water. This makes the ice with salt on it melt faster, which is why we salt the roads in an ice storm.

Researchers in the US have wound back the cosmic clock to determine that a spectacular comet whizzed past the Earth 5,000 years ago.

While the event isn't recorded in any historical account, the team were able to gather clues from more recently sighted comets.

In a paper published in the Astronomical Journal, they examined observations made by the Hubble Space Telescope of the comet ATLAS (C/2019 Y4), which Hubble watched break into pieces last year.

This comet is thought to be a fragment of a larger one that passed by the Earth in 1844, shining as brightly as Sirius, the brightest star in the sky.


By tracing the two comets' motions back through time, the researchers figured out that they are likely both parts of an even bigger one that last zipped through the inner Solar System 5,000 years ago, around the time that Ancient Egyptians were first settling into the Nile valley.

Elon Musk's Tesla said it is using technology tested out on self-driving cars to build a humanoid robot designed to assist humans in day-to-day work. The prototype is set to be unveiled next year.

The news was announced on Tesla's AI Day, which was streamed on the company's website Thursday night.

The presentation began with a person in a robot suit performing a variety of dances on stage. Musk quickly stepped in to assure everyone that "that was not real."

He then said that the prototype of a humanoid robot with a similar design, called 'Tesla Bot', will be ready sometime next year.

Ice losses from Thwaites Glacier in West Antarctica are currently responsible for roughly four percent of the global sea-level rise. This figure could increase, since virtually no another ice stream in the Antarctic is changing as dramatically as the massive Thwaites Glacier. Until recently, experts attributed these changes to climate change and the fact that the glacier rests on the seafloor in many places, and as such comes into contact with warm water masses. But there is also a third, and until now one of the most difficult to constrain, influencing factors. In a new study, German and British researchers have shown that there is a conspicuously large amount of heat from Earth's interior beneath the ice, which has likely affected the sliding behaviour of the ice masses for millions of years. This substantial geothermal heat flow, in turn, are due to the fact that the glacier lies in a tectonic trench, where the Earth's crust is significantly thinner than it is e.g. in neighbouring East Antarctica. The new study was published today in the Nature online journal Communications Earth & Environment.

Unlike East Antarctica, West Antarctica is a geologically young region. In addition, it doesn't consist of a large contiguous land mass, where the Earth's crust is up to 40 kilometres thick, but instead is made up of several small and for the most part relatively thin crustal blocks that are separated from each other by a so-called trench system or rift system. In many of the trenches in this system, the Earth's crust is only 17 to 25 kilometres thick, and as a result a large portion of the ground lies one to two kilometres below sea level. On the other hand, the existence of the trenches has long led researchers to assume that comparatively large amounts of heat from Earth's interior rose to the surface in this region. With their new map of this geothermal heat flow in the hinterland of the West Antarctic Amundsen Sea, experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the British Antarctic Survey (BAS) have now provided confirmation.