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The flow of time isn’t as consistent as we might think – gravity slows it down, so clocks on the surface of Earth tick slower than those in space. Now researchers have measured time passing at different speeds across just one millimeter, the smallest distance yet.

The idea that time would be affected by gravity was first proposed by Albert Einstein in 1915, as part of his theory of general relativity. Space and time are inextricably linked, and large masses warp the fabric of spacetime with their immense gravitational influence. This has the effect of making time pass more slowly closer to a large mass like a planet, star, or, in the most extreme example, a black hole. This phenomenon is known as time dilation.

Here on Earth, time dilation effectively means that time moves more quickly at higher elevations. So for instance, time passes faster on the summit of Mount Everest than at sea level, but it applies over smaller distances too – someone living in a 10th floor apartment will age faster than someone on the first floor, and your head ages faster than your feet.

New research has shown that future gravitational wave detections from space will be capable of finding new fundamental fields and potentially shed new light on unexplained aspects of the Universe.

Professor Thomas Sotiriou from the University of Nottingham’s Centre of Gravity and Andrea Maselli, researcher at GSSI and INFN associate, together with researchers from SISSA, and La Sapienza of Rome, showed the unprecedented accuracy with which gravitational wave observations by the space interferometer LISA (Laser Interferometer Space Antenna), will be able to detect new fundamental fields. The research has been published in Nature Astronomy.

In this new study researchers suggest that LISA, the space-based gravitational-wave (GW) detector which is expected to be launched by ESA in 2037 will open up new possibilities for the exploration of the Universe.

Most energy-producing technologies used today are unsustainable, as they cause significant damage to our planet’s natural environment. In recent years, scientists worldwide have thus been trying to devise alternative energy solutions that take advantage of abundant and natural resources.

In addition to , wind and seawater energy solutions, some physicists and engineers have been exploring the possibility of sourcing energy from nuclear reactions. This is the process through which two atomic nuclei combine to form a heavier nucleus and an energetic neutron.

Two research teams working at the Lawrence Livermore National Laboratory’s (LLNL) National Ignition Facility (NIF) demonstrated new approaches to increase nuclear energy production via a laser-driven . Their findings, published in recent Nature and Nature Physics papers, open new exciting possibilities for one day using self-heating plasmas as sustainable energy sources.

Researchers from the Institute of High Energy Physics of the Chinese Academy of Sciences examined the validity of the theory of relativity with the highest accuracy in a study entitled “Exploring Lorentz Invariance Violation from Ultrahigh-Energy γRays Observed by LHAASO,” which was published in the latest issue of Physical Review Letters.

According to Einstein’s of relativity, the fastest speed of matter in the Universe is the speed of light. Whether that limit is breachable can be tested by examining Lorentz breaking or Lorentz invariance violation.

“Using the world’s highest energy gamma rays observed by the Large High Altitude Air-shower Observatory (LHAASO), a large-scale cosmic ray experiment in Daocheng, Sichuan province, China, we tested Lorentz symmetry. The result improves the breaking energy scale of Lorentz symmetry by dozens of times compared with the previous best result. This is the most rigorous test of a Lorentz symmetry breaking form, confirming once again the validity of Einstein’s relativistic space-time symmetry,” said Prof. Bi Xiaojun, one of the paper’s corresponding authors. Prof. BI is a scientist at the Institute of High Energy Physics and a member of the LHAASO collaboration.

A study by the University of Bonn: Observations fit poorly with the Standard Model of Cosmology.

The Standard Model of Cosmology describes how the universe came into being according to the view of most physicists. Researchers at the University of Bonn have now studied the evolution of galaxies within this model, finding considerable discrepancies with actual observations. The University of St. Andrews in Scotland and Charles University in the Czech Republic were also involved in the study. The results have now been published in the Astrophysical Journal.

Most galaxies visible from Earth resemble a flat disk with a thickened center. They are therefore similar to the sports equipment of a discus thrower. According to the Standard Model of Cosmology, however, such disks should form rather rarely. This is because in the model, every galaxy is surrounded by a halo of dark matter. This halo is invisible, but exerts a strong gravitational pull on nearby galaxies due to its mass. “That’s why we keep seeing galaxies merging with each other in the model universe,” explains Prof. Dr. Pavel Kroupa of the Helmholtz Institute for Radiation and Nuclear Physics at the University of Bonn.

Researchers from Chalmers University of Technology have produced a structural battery that performs ten times better than all previous versions. It contains carbon fiber that serves simultaneously as an electrode, conductor, and load-bearing material. Their latest research breakthrough paves the way for essentially ’massless’ energy storage in vehicles and other technology.

The batteries in today’s electric cars constitute a large part of the vehicles’ weight, without fulfilling any load-bearing function. A structural battery, on the other hand, is one that works as both a power source and as part of the structure – for example, in a car body. This is termed ‘massless’ energy storage, because in essence the battery’s weight vanishes when it becomes part of the load-bearing structure. Calculations show that this type of multifunctional battery could greatly reduce the weight of an electric vehicle.

The development of structural batteries at Chalmers University of Technology has proceeded through many years of research, including previous discoveries involving certain types of carbon fiber. In addition to being stiff and strong, they also have a good ability to store electrical energy chemically. This work was named by Physics World as one of 2018’s ten biggest scientific breakthroughs.

It’s hard to spot a black hole.


There are two different approaches to such detection. In “X-ray binary stars” — in which a star and a black hole orbit a shared center while producing X-rays — a black hole’s gravitational field can pull material from its companion. The material circles the black hole, heating up by friction as it does so.

The hot material glows brightly in X-ray light, making the black hole visible, before being sucked into the black hole and disappearing. You can also detect pairs of black holes as they merge together, spiraling inwards and emitting a brief flash of gravitational waves, which are ripples in spacetime.

There are many rogue black holes that are drifting through space without interacting with anything, however — making them hard to detect. That’s a problem, because if we can’t detect isolated black holes, then we can’t learn about how they formed and about the deaths of the stars they came from.

We can’t make transistors any smaller, is this the end of Moore’s Law?

There has been a lot of talk about the end of Moore’s Law for at least a decade now and what kind of implications this will have on modern society. Since the invention of the computer transistor in 1947, the number of transistors packed onto the silicon chips that power the modern world has steadily grown in density, leading to the exponential growth of computing power over the last 70 years. A transistor is a physical object, however, and being purely physical it is governed by laws of physics like every other physical object. That means there is a physical limit to how small a transistor can be. Back when Gordon Moore made his famous prediction about the pace of growth in computing power, no one was really thinking about transistors at nanometer scales. But as we enter the third decade of the 21st century, our reliance on packing more transistors into the same amount of silicon is brushing up against the very boundaries of what is physically possible, leading many to worry that the pace of innovation we’ve become accustomed to might come to a screeching end in the very near future.

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Scientists tell us that transistors can’t be made any smaller, sounding the end of Moore’s Law. Does this threaten our progress in the future?