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Some of nature’s mysteries have kept scientists busy for decades—for example, the processes that drive evolution. The question of whether certain differences between and within species are caused by natural selection or by chance processes divides evolutionary biologists even today. Now, an international team of researchers has teased apart a scientific debate concerning the evolutionary theories of Darwin and the Japanese geneticist Kimura. Their conclusion: the debate is unnecessarily convoluted by the co-existence of different interpretations.

Due to his contributions to geological and , British naturalist Charles Darwin (1809–1882) is considered one of the most important natural scientists. His influential work “On the Origin of Species” (1859), with its strictly scientific explanation of the diversity of life, forms the basis of modern evolutionary biology. Darwin concluded that species evolve through natural selection: well-adapted organisms survive, others don’t.

However, by the end of the 1960s, the Japanese geneticist Motoo Kimura (1924–1994) proposed that at the genetic level, most changes in the course of evolution do not offer direct advantages or disadvantages to the individual but are simply neutral. According to his “Neutral Theory of Molecular Evolution,” first published in 1968, most of the within and between species arises from random fluctuations of neutral mutations.

Dr. Michael Demkowicz predicted self-healing in metal; this summer it was finally observed, shocking scientists around the world.

A microscopic crack grew in a very small piece of platinum when placed under repetitive stretching. The experiment, designed to study fatigue crack growth, continued as predicted for a while. But then, something unexpected happened. The crack stopped growing and instead began to get shorter, effectively “healing” itself.

This incredible observation was made by a group of researchers at Sandia National Laboratories while conducting fracture experiments on nanocrystalline metals. The findings were recently published in the journal Nature.

Researcher show that n-bit integers can be factorized by independently running a quantum circuit with orders of magnitude fewer qubits many times. It then use polynomial-time classical post-processing. The correctness of the algorithm relies on a number-theoretic heuristic assumption reminiscent of those used in subexponential classical factorization algorithms. It is currently not clear if the algorithm can lead to improved physical implementations in practice.

Shor’s celebrated algorithm allows to factorize n-bit integers using a quantum circuit of size O(n^2). For factoring to be feasible in practice, however, it is desirable to reduce this number further. Indeed, all else being equal, the fewer quantum gates there are in a circuit, the likelier it is that it can be implemented without noise and decoherence destroying the quantum effects.

The new algorithm can be thought of as a multidimensional analogue of Shor’s algorithm. At the core of the algorithm is a quantum procedure.

Falling through the Solar System at an astonishing 635,266 kilometers (394,736 miles) per hour, NASA’s Parker Solar Probe has just smashed the record for fastest object ever to be created by human hands.

The event on September 27 marks the turning point of the mission’s 17th loop around the Sun as it collects data on the heated winds of charged particles and violent magnetism that surround our closest star, and comes just under three years after its previous record of 586,863.4 kilometers (364,660 miles) per hour.

At these speeds, it’d be possible for an aircraft to circumnavigate our planet roughly 15 times in a single hour, or zoom from New York to Los Angeles in just over 20 seconds.

Centenarians, once considered rare, have become commonplace. Indeed, they are the fastest-growing demographic group of the world’s population, with numbers roughly doubling every ten years since the 1970s.

How long humans can live, and what determines a long and healthy life, have been of interest for as long as we know. Plato and Aristotle discussed and wrote about the ageing process over 2,300 years ago.

The pursuit of understanding the secrets behind exceptional longevity isn’t easy, however. It involves unravelling the complex interplay of genetic predisposition and lifestyle factors and how they interact throughout a person’s life.

Caltech researchers have discovered Hubbard excitons, which are excitons bound magnetically, offering new avenues for exciton-based technological applications.

In art, the negative space in a painting can be just as important as the painting itself. Something similar is true in insulating materials, where the empty spaces left behind by missing electrons play a crucial role in determining the material’s properties. When a negatively charged electron is excited by light, it leaves behind a positive hole. Because the hole and the electron are oppositely charged, they are attracted to each other and form a bond. The resulting pair, which is short-lived, is known as an exciton [pronounced exit-tawn].

Excitons are integral to many technologies, such as solar panels, photodetectors, and sensors. They are also a key part of light-emitting diodes found in televisions and digital display screens. In most cases, the exciton pairs are bound by electrical, or electrostatic, forces, also known as Coulomb interactions.