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Archive for the ‘physics’ category: Page 67

Oct 19, 2022

The most precise accounting yet of dark energy and dark matter

Posted by in categories: cosmology, evolution, physics

Astrophysicists have performed a powerful new analysis that places the most precise limits yet on the composition and evolution of the universe. With this analysis, dubbed Pantheon+, cosmologists find themselves at a crossroads.

Pantheon+ convincingly finds that the cosmos is composed of about two-thirds dark energy and one-third matter—mostly in the form of dark matter—and is expanding at an accelerating pace over the last several billion years. However, Pantheon+ also cements a major disagreement over the pace of that expansion that has yet to be solved.

By putting prevailing modern cosmological theories, known as the Standard Model of Cosmology, on even firmer evidentiary and statistical footing, Pantheon+ further closes the door on alternative frameworks accounting for dark energy and dark matter. Both are bedrocks of the Standard Model of Cosmology but have yet to be directly detected and rank among the model’s biggest mysteries. Following through on the results of Pantheon+, researchers can now pursue more precise observational tests and hone explanations for the ostensible cosmos.

Oct 19, 2022

Physicists confirm hitch in proton structure

Posted by in category: physics

Nuclear physicists have confirmed that the current description of proton structure isn’t all smooth sailing. A new precision measurement of the proton’s electric polarizability performed at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility has revealed a bump in the data in probes of the proton’s structure.

Though widely thought to be a fluke when seen in earlier measurements, this new, more precise measurement has confirmed the presence of the anomaly and raises questions about its origin. The research has just been published in the journal Nature.

According to Ruonan Li, first author on the new paper and a graduate student at Temple University, measurements of the ’s electric polarizability reveal how susceptible the proton is to deformation, or stretching, in an electric field. Like size or charge, the electric polarizability is a fundamental property of proton structure.

Oct 19, 2022

Record-Breaking Gamma Ray Burst May Indicate Birth of a Black Hole

Posted by in categories: cosmology, physics, robotics/AI

On Oct. 9, an unimaginably powerful influx of X-rays and gamma rays infiltrated our solar system. It was likely the result of a massive explosion that happened 2.4 billion light-years away from Earth, and it has left the science community stunned.

In the wake of the explosion, astrophysicists worldwide turned their telescopes toward the spectacular show, watching it unfold from a variety of cosmic vantage points — and as they vigilantly studied the event’s glimmering afterglow over the following week, they grew shocked by how utterly bright this gamma-ray burst seems to have been.

Eventually, the spectacle’s sheer intensity earned it a fitting (very millennial) name to accompany its robotic title of GRB221009A: B.O.A.T. — the “brightest of all time.”

Oct 19, 2022

Nuclear physics experiments are extremely data intensive

Posted by in categories: physics, robotics/AI

Now, #AI and #MachineLearning systems have proven that they can keep up with the torrent by processing raw experimental data in real-time. https://www.jlab.org/news/stories/trial-run-smart-streaming-readouts

Oct 18, 2022

New tool allows scientists to peer inside neutron stars

Posted by in categories: information science, physics, space

Imagine taking a star twice the mass of the sun and crushing it to the size of Manhattan. The result would be a neutron star—one of the densest objects found anywhere in the universe, exceeding the density of any material found naturally on Earth by a factor of tens of trillions. Neutron stars are extraordinary astrophysical objects in their own right, but their extreme densities might also allow them to function as laboratories for studying fundamental questions of nuclear physics, under conditions that could never be reproduced on Earth.

Because of these exotic conditions, scientists still do not understand what exactly themselves are made from, their so-called “equation of state” (EoS). Determining this is a major goal of modern astrophysics research. A new piece of the puzzle, constraining the range of possibilities, has been discovered by a pair of scholars at IAS: Carolyn Raithel, John N. Bahcall Fellow in the School of Natural Sciences; and Elias Most, Member in the School and John A. Wheeler Fellow at Princeton University. Their work was recently published in The Astrophysical Journal Letters.

Continue reading “New tool allows scientists to peer inside neutron stars” »

Oct 18, 2022

Shortly Before They Collided, two Black Holes Tangled Spacetime up Into Knots

Posted by in categories: cosmology, physics

In February 2016, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the first-ever detection of gravitational waves (GWs). Originally predicted by Einstein’s Theory of General Relativity, these waves are ripples in spacetime that occur whenever massive objects (like black holes and neutron stars) merge. Since then, countless GW events have been detected by observatories across the globe – to the point where they have become an almost daily occurrence. This has allowed astronomers to gain insight into some of the most extreme objects in the Universe.

In a recent study, an international team of researchers led by Cardiff University observed a binary black hole system originally detected in 2020 by the Advanced LIGO, Virgo, and Kamioki Gravitational Wave Observatory (KAGRA). In the process, the team noticed a peculiar twisting motion (aka. a precession) in the orbits of the two colliding black holes that was 10 billion times faster than what was noted with other precessing objects. This is the first time a precession has been observed with binary black holes, which confirms yet another phenomenon predicted by General Relativity (GR).

Continue reading “Shortly Before They Collided, two Black Holes Tangled Spacetime up Into Knots” »

Oct 18, 2022

The Vacuum Catastrophe. The Worst Thing That Can Happen to the Universe

Posted by in categories: physics, space

In this video, you are going to learn: what dangers are waiting for us in seemingly empty places? Can physicists on Earth destroy the entire cosmos? And most importantly, can a vacuum end the world we know and love?

Oct 18, 2022

Spacecraft Makes Progress on Solar Heating Mystery

Posted by in categories: energy, physics

Data from the Parker Solar Probe confirms a long-suspected heat source for the Sun’s surprisingly hot corona, but there may be others.

The Sun’s surface temperature is around six thousand degrees kelvin, but the solar atmosphere—the corona and the solar wind—can reach a million degrees kelvin, a long-standing mystery in solar physics. Now, with data from the Parker Solar Probe, researchers have found evidence supporting a partial explanation for this mystery: magnetic waves driven by subsurface turbulence can impart energy to ions in these regions [1].

The exact mechanism of heating has been debated for decades, but the story appears to start with turbulent flow in the Sun’s convection zone, the outermost layer below the surface. In fluid dynamics, turbulence causes heating through a process known as turbulent energy cascade, where large eddies are converted into progressively smaller eddies. The energy in the smallest eddies is converted into heat through collisions between molecules.

Oct 16, 2022

What Drives Galaxies? The Milky Way’s Black Hole May Be the Key

Posted by in categories: cosmology, physics

On May 12, at nine simultaneous press conferences around the world, astrophysicists revealed the first image of the black hole at the heart of the Milky Way. At first, awesome though it was, the painstakingly produced image of the ring of light around our galaxy’s central pit of darkness seemed to merely prove what experts already expected: The Milky Way’s supermassive black hole exists, it is spinning, and it obeys Albert Einstein’s general theory of relativity.

And yet, on closer inspection, things don’t quite stack up.

Oct 16, 2022

Danish Physicist Lene Hau was Able to Slow Down the Speed of Light to 38 mph and was Eventually Able to Manipulate it

Posted by in category: physics

The speed of light is a universal physical constant that is important in many aspects of physics. Light travels at a continuous and finite speed of 186,000 miles per second. But did you have note that the speed of light can be manipulated?

In 1999, Lene Hau, a physicist from Denmark, was the first to slow light down to only 38 mph. Later, she could totally stop, control, and move it.

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