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Archive for the ‘cosmology’ category: Page 226

Dec 12, 2021

Discovering Dark Matter: New Clue From Mysterious Clouds Circling Spinning Black Holes

Posted by in categories: cosmology, physics

Gravitational waves are cosmic ripples in the fabric of space and time that emanate from catastrophic events in space, like collisions of black holes and neutron stars — the collapsed cores of massive supergiant stars. Extremely sensitive gravitational-wave detectors on Earth, like the Advanced LIGO

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory supported by the National Science Foundation and operated by Caltech and MIT. It’s designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. It’s multi-kilometer-scale gravitational wave detectors use laser interferometry to measure the minute ripples in space-time caused by passing gravitational waves. It consists of two widely separated interferometers within the United States—one in Hanford, Washington and the other in Livingston, Louisiana.

Dec 11, 2021

Watch NASA’s IXPE Observatory Launch Into Space — Official Live Broadcast

Posted by in categories: cosmology, satellites

We’re sending a new pair of X-ray eyes into the universe!

NASA’s Imaging X-ray Polarimetry Explorer (IXPE) is our first satellite dedicated to measuring the polarization of X-rays. Polarized light is made up of electric fields that vibrate in a single direction—and IXPE’s state-of-the-art X-ray vision will help scientists study the spin of black holes, the magnetic fields of pulsars, and other cosmic phenomena.

Continue reading “Watch NASA’s IXPE Observatory Launch Into Space — Official Live Broadcast” »

Dec 10, 2021

Neural network analyzes gravitational waves in real time

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

Black holes are one of the greatest mysteries of the universe—for example, a black hole with the mass of our sun has a radius of only 3 kilometers. Black holes in orbit around each other emit gravitational radiation—oscillations of space and time predicted by Albert Einstein in 1916. This causes the orbit to become faster and tighter, and eventually, the black holes merge in a final burst of radiation. These gravitational waves propagate through the universe at the speed of light, and are detected by observatories in the U.S. (LIGO) and Italy (Virgo). Scientists compare the data collected by the observatories against theoretical predictions to estimate the properties of the source, including how large the black holes are and how fast they are spinning. Currently, this procedure takes at least hours, often months.

An interdisciplinary team of researchers from the Max Planck Institute for Intelligent Systems (MPI-IS) in Tübingen and the Max Planck Institute for Gravitational Physics (Albert Einstein Institute/AEI) in Potsdam is using state-of-the-art machine learning methods to speed up this process. They developed an algorithm using a , a complex computer code built from a sequence of simpler operations, inspired by the human brain. Within seconds, the system infers all properties of the binary black-hole source. Their research results are published today in Physical Review Letters.

“Our method can make very accurate statements in a few seconds about how big and massive the two were that generated the gravitational waves when they merged. How fast do the black holes rotate, how far away are they from Earth and from which direction is the gravitational wave coming? We can deduce all this from the observed data and even make statements about the accuracy of this calculation,” explains Maximilian Dax, first author of the study Real-Time Gravitational Wave Science with Neural Posterior Estimation and Ph.D. student in the Empirical Inference Department at MPI-IS.

Dec 10, 2021

Toward achieving megatesla magnetic fields in the laboratory

Posted by in categories: cosmology, particle physics, supercomputing

Recently, a research team at Osaka University has successfully demonstrated the generation of megatesla (MT)-order magnetic fields via three-dimensional particle simulations on laser-matter interaction. The strength of MT magnetic fields is 1–10 billion times stronger than geomagnetism (0.3–0.5 G), and these fields are expected to be observed only in the close vicinity of celestial bodies such as neutron stars or black holes. This result should facilitate an ambitious experiment to achieve MT-order magnetic fields in the laboratory, which is now in progress.

Since the , scientists have strived to achieve the highest magnetic fields in the laboratory. To date, the highest magnetic field observed in the laboratory is in the kilotesla (kT)-order. In 2020, Masakatsu Murakami at Osaka University proposed a novel scheme called microtube implosions (MTI) to generate ultrahigh magnetic fields on the MT-order. Irradiating a micron-sized hollow cylinder with ultraintense and generates with velocities close to the speed of light. Those hot electrons launch a cylindrically symmetric implosion of the inner wall ions towards the central axis. An applied pre-seeded of the kilotesla-order, parallel to the central axis, bends the trajectories of ions and electrons in opposite directions because of the Lorentz force. Near the target axis, those bent trajectories of ions and electrons collectively form a strong spin current that generates MT-order magnetic fields.

In this study, one of the , Didar Shokov, has extensively conducted three-dimensional simulations using the supercomputer OCTOPUS at Osaka University’s Cybermedia Center. As a result, a distinct scaling law has been found relating the performance of the generation of the magnetic fields by MTI and such external parameters as applied laser intensity, laser energy, and target size.

Dec 9, 2021

SpaceX Falcon 9 rocket launches NASA’s new IXPE X-ray space telescope

Posted by in categories: cosmology, physics

IXPE will probe the physics behind some of the universe’s most dynamic objects: black holes and neutron stars.


CAPE CANAVERAL, Fla. — SpaceX successfully launched its 28th rocket of the year early Thursday morning (Dec. 9), ferrying an X-ray observatory into space for NASA.

A used Falcon 9 rocket blasted off at 1 a.m. (0600 GMT) from Pad 39A here at NASA’s Kennedy Space Center in Florida, carrying the Imaging X-ray Polarimetry Explorer (IXPE). The mission marked the fifth flight for this particular booster.

Dec 8, 2021

Gravitational waves could be key to answering why more matter was left over after Big Bang

Posted by in categories: cosmology, particle physics

A team of theoretical researchers have found it might be possible to detect Q-balls in gravitational waves, and their detection would answer why more matter than anti-matter to be left over after the Big Bang, reports a new study in Physical Review Letters.

The reason humans exist is because at some in the first second of the Universe’s existence, somehow more matter was produced than anti-matter. The asymmetry is so small that only one extra particle of matter was produced every time ten billion particles of anti matter were produced. The problem is that even though this asymmetry is small, current theories of physics cannot explain it. In fact, standard theories say matter and anti matter should have been produced in exactly equal quantities, but the existence of humans, Earth, and everything else in the universe proves there must be more, undiscovered physics.

Currently, a popular idea shared by researchers is that this asymmetry was produced just after inflation, a period in the early when there was a very rapid expansion. A blob of could have stretched out over the horizon to evolve and fragment in just the right way to produce this asymmetry.

Dec 6, 2021

Galaxy Discovered With No Trace of Dark Matter

Posted by in category: cosmology

An international team of astronomers led by researchers from the Netherlands has found no trace of dark matter in the galaxy AGC 114,905, despite taking detailed measurements over a course of forty hours with state-of-the-art telescopes. They will present their findings in Monthly Notices of the Royal Astronomical Society.

When Pavel Mancera Piña (University of Groningen and ASTRON, the Netherlands) and his colleagues discovered six galaxies with little to no dark matter, they were told “measure again, you’ll see that there will be dark matter around your galaxy.” However, after forty hours of detailed observations using the Very Large Array (VLA) in New Mexico (United States), the evidence for a dark matter-free galaxy only became stronger.

The galaxy in question, AGC 114,905, is about 250 million light-years away. It is classified as an ultra-diffuse dwarf galaxy, with the name ‘dwarf galaxy’ referring to its luminosity and not to its size. The galaxy is about the size of our own Milky Way but contains a thousand times fewer stars. The prevailing idea is that all galaxies, and certainly ultra-diffuse dwarf galaxies, can only exist if they are held together by dark matter.

Dec 6, 2021

The world’s biggest laser: Function, fusion power and solving a supernova

Posted by in categories: cosmology, nuclear energy, satellites

If someone told you that the world’s biggest laser was in California that has something to do with space and national defence, you might imagine it was a super-weapon designed to blast enemy satellites out of the sky. But the reality is quite different. The new laser is a unique research tool for scientists, capable of creating the extreme conditions that exist inside stars and nuclear explosions.

The giant laser is located at the Lawrence Livermore National Laboratory (LLNL) in Livermore, California, and it goes by the rather cryptic name of the National Ignition Facility (NIF). That’s because, in the context of nuclear science, “ignition” has a very specific meaning according to the Lawrence Livermore National Laboratory. It refers to the point at which a fusion reaction becomes self-sustaining – a condition that is found inside the sun and other stars, but is extremely difficult to achieve in an earthbound laboratory. Triggering nuclear fusion requires enormously high temperatures and pressures, and that’s where NIF’s giant laser comes in.

Dec 6, 2021

Sean Carroll: Is Consciousness Emergent?

Posted by in categories: cosmology, neuroscience, physics

Theoretical physicist Sean Carroll joins us to discuss whether it make sense to think of consciousness as an emergent phenomenon, and whether contemporary physics points in this direction.

We discussed Sean’s essay responding to Philip’s book ‘Galileo’s Error,’ and Philip’s counter-response essay. Both are available here: https://conscienceandconsciousness.com/2021/08/01/19-essays-on-galileos-error/

Continue reading “Sean Carroll: Is Consciousness Emergent?” »

Dec 5, 2021

Scientists Discover Enormous Black Hole Right Near Our Galaxy

Posted by in category: cosmology

Astronomers from the University of Texas have spotted a gigantic black hole at the heart of our galaxy’s many dwarf satellite galaxies — meaning that, in intergalactic terms, it’s just a stone’s throw away from our own Solar System.

The newly discovered black hole, dubbed Leo I, is roughly the same size as the suspected black hole at the center of the Milky Way.

It also appears to be a bit of an oddball. By measuring the gravitational pull it has on the stars surrounding it, the researchers found that it’s absolutely massive compared to the size of its host galaxy.