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The results of Nature’s fifth survey of PhD students bear out Kovacevic’s experience, telling a story of personal reward and resilience against a backdrop of stress, uncertainty and struggles with depression and anxiety. The survey drew self-selecting responses from more than 6,300 early-career researchers — the most in the survey’s ten-year history. The respondents hail from every part of the globe and represent the full spectrum of scientific fields.


Nature’s survey of more than 6,000 graduate students reveals the turbulent nature of doctoral research.

Determining the quantum mechanical behavior of many interacting particles is essential to solving important problems in a variety of scientific fields, including physics, chemistry and mathematics. For instance, in order to describe the electronic structure of materials and molecules, researchers first need to find the ground, excited and thermal states of the Born-Oppenheimer Hamiltonian approximation. In quantum chemistry, the Born-Oppenheimer approximation is the assumption that electronic and nuclear motions in molecules can be separated.

A variety of other scientific problems also require the accurate computation of Hamiltonian ground, excited and thermal states on a quantum computer. An important example are combinatorial optimization problems, which can be reduced to finding the ground state of suitable spin systems.

So far, techniques for computing Hamiltonian eigenstates on quantum computers have been primarily based on phase estimation or variational algorithms, which are designed to approximate the lowest energy eigenstate (i.e., ground state) and a number of excited states. Unfortunately, these techniques can have significant disadvantages, which make them impracticable for solving many scientific problems.

A team at Samsung Advanced Institute of Technology has announced that they have improved quantum dot (QD) technology for use in large displays by developing QDs that are both more efficient and have no heavy metals. In their paper published in the journal Nature, the group describes their work and their plans for the future. Alexander Efros, with the Naval Research Laboratory, in Washington D.C. has published a companion piece in the same journal issue outlining the work by the team at Samsung.

Quantum dots are nanoscale semiconducting crystals that have unique optical and electronic properties due to quirks of quantum mechanics. Since their development in the 1980s, scientists have been finding many uses for them in optical devices. Unfortunately, as Efros notes, they suffer from two problems that have prevented them from being fully utilized. The first is that they are based on cadmium, a toxic heavy metal. The second is the QD phosphors that are used in display devices—they are not self- emissive, which means they need to be replaced by QD light-emitting diodes in order for them to be competitively efficient. Notably current Samsung QLED TV screens do not use the QLEDs as a source of light—instead, LCDs produce backlight which is then absorbed by a film of quantum dots. In this new effort, the group at Samsung has made progress towards addressing both problems.

O,.,o.


In 1981 astronomer Robert Kirshner made a shocking intergalactic discovery. 700 million light years from the Earth lies an enormous, barren sphere known as the Boötes Void. Its very existence challenges what we know about the universe and its origins. The Void is at least ten times larger than the rules of modern physics say is reasonably likely. As a structure, the Void verges on the impossible.

Yet, this disturbing formation is consistent with Nikolai Kardashev’s 1962 theory of advanced alien civilizations and their behavior. Could it be home to a hyper-intelligent extraterrestrial species? A void is a massive region of space that holds either minimal or no galaxies. They are created when mass collapses, and is followed by subatomic particle implosions. With a diameter of 330 million light years, the Boötes Void makes up 0.27% of the observable universe. But according to established scientific understanding its huge size is impossible. The Big Bang theory states that the universe is 14 billion years old, and that it has been expanding exponentially since its birth. Given the age of the universe, there has only been enough time for voids to form that are tens of millions of light years across, not hundreds. Stranger still, is just how empty the Bootes Void is.

It contains only 60 galaxies, around 10,000 fewer than we should expect to find in such a vast expanse. Many believe this means the void is the first observable proof of a Kardashev scale III “master race” civilization. In 1964 Nikolai Kardashev – now Deputy Director of Russia’s Astro Space Centre – published his theory for extra terrestrial development, arguing that civilizations develop in 4 stages. A civilization reaches the third phase when it becomes so technologically advanced that it is able to convert starlight into usable energy. At this point, the species is able to replicate itself at astonishing rates, spreading out across the universe and colonizing galaxies. Many consider this is a necessary step for any civilization to avoid extinction. Could this explain the Void’s chilling dearth of stars?

New Delhi: Six central forensic laboratories in the country will soon be upgraded for carrying out efficient and scientific investigation in serious and heinous crimes, officials said on Sunday.

The central forensic science laboratories (CFSLs) which will be upgraded with capacity enhancement are located at Chandigarh, Hyderabad, Kolkata, Bhopal, Pune and Guwahati.

“The Ministry of Home Affairs has decided to enhance the capacity of six CFSLs under the Directorate of Forensic Science Services in the area of forensic psychology involving external experts,” an official said.