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* At Long Last, Mathematical Proof That Black Holes Are Stable * Who Gets to Work in the Digital Economy? * Mice produce rat sperm with technique that could help conservation.

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The electrification of heating systems could play a significant role in building decarbonization. Heat pumps are emerging as a solution.


Iranian scientists have demonstrated a multi-layer silicon nanoparticle (SNP) solar cell based on nanoparticles that are densely stacked inside a dielectric medium. They considered different SNP structures and configurations to tailor these particles as a p–n junction cell.

“This is because SNPs are assumed to be the main absorber in the cell. Thus, any distance between them reduces the absorption of incident photons,” the group said.

They considered different SNP structures and configurations to tailor these particles as a p–n junction cell. They said this kind of cell could achieve a theoretical efficiency of around 11%.

Tiny crystals, known as quantum dots, have enabled an international team to achieve a quantum efficiency exceeding 100 percent in the photocurrent generated in a hybrid inorganic-organic semiconductor.

Perovskites are exciting semiconductors for light-harvesting applications and have already shown some impressive performances in solar cells. But improvements in photo-conversion efficiency are necessary to take this technology to a broader market.

Light comes in packets of energy known as photons. When a semiconductor absorbs a photon, the is transferred to a negatively charged electron and its positively charged counterpart, known as a hole. An can sweep these particles in , thereby allowing a current to flow. This is the basic operation of a solar cell. It might sound simple, but optimizing the quantum efficiency, or getting as many from the incoming photons as possible, has been a long-standing goal.

The received view in physics is that the direction of time is provided by the second law of thermodynamics, according to which the passage of time is measured by ever-increasing disorder in the universe. This view, Julian Barbour argues, is wrong. If we reject Newton’s faulty assumptions about the existence of absolute space and time, Newtonian dynamics can be shown to provide a very different arrow of time. Its direction, according to this theory, is given by the increase in the complexity and order of a system of particles, exactly the opposite of what the received view about time suggests.

Two of the most established beliefs of contemporary cosmology are that the universe is expanding and that the direction of the arrow of time in the universe is defined by ever-increasing disorder (entropy), as described by the second law of thermodynamics. But both of these beliefs rest on shaky ground. In saying that the universe is expanding, physicists implicitly assume its size is measured by a rod that exists outside the universe, providing an absolute scale. It’s the last vestige of Newton’s absolute space and should have no place in modern cosmology. And in claiming that entropy is what gives time its arrow, physicists uncritically apply the laws of thermodynamics, originally discovered through the study of steam engines, to the universe as a whole. That too needs to be questioned.

Time min

Einstein and why the block universe is a mistake Read more In the absence of an absolute space and external measuring rods, size is always relative — relative to a measure of distance internal to the system. Starting from the simplest case, a triangle, what we find is that the internal measure of size produces a ratio which also happens to be related to a mathematical measure of complexity that intriguingly plays the central role in Newtonian universal gravitation. Applying these findings to the universe as a whole, we find that Newton’s theory of gravity, contrary to what physicists believe, contains within it an intrinsic arrow of time. This provides a strong hint that the direction of time is not defined by an increase in entropy, but by an increase in structure and complexity.

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The University of Innsbruck, Austria, realized a quantum computer that breaks out of this paradigm and unlocks additional computational resources, hidden in almost all of today’s quantum devices. Computers are well-known for operating with binary information, or zeros and ones, which has led to computers powering so much. This new approach results in more computational power with fewer quantum particles.

Quantum computers work with more than zero and one and digital computers work with zeros and ones, also called binary information. Quantum computers are also designed with binary information processing in mind. In fact, it was so successful that computers now power everything from coffee makers to self-driving cars, and it’s hard to imagine life without them. Restricting researchers to binary systems prevent these devices from living up to their true potential.

The research team succeeded in developing a quantum computer that can perform arbitrary calculations with so-called quantum digits, thereby unlocking more computational power with fewer quantum particles. Unlike the classical method, the new method that utilizes more states does not negatively impact the reliability of the computer. The researchers have developed a quantum computer that can make use of the full potential of these atoms.