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Archive for the ‘cosmology’ category: Page 236

Mar 16, 2021

Wormholes Across The Universe Are Fully Traversable, New Calculations Show

Posted by in categories: cosmology, particle physics, space travel

In my last post, I talked about the idea of warp drive and whether it might one day be possible. Today I’ll talk about another faster-than-light trick: wormholes.

Wormholes are an old idea in general relativity. It’s based on work by Albert Einstein and Nathan Rosen, who tried to figure out how elementary particles might behave in curved spacetime. Their idea treated particle-antiparticle pairs as two ends of a spacetime tube.

This Einstein-Rosen Bridge would look like a black hole on one end, and an anti-black hole, or white hole, on the other end.

Mar 14, 2021

New Floquet maser is very good at detecting low frequency magnetic fields

Posted by in categories: cosmology, particle physics

A new type of maser made from periodically driven xenon atoms can detect low frequency magnetic fields far better than any previous magnetometer, according to scientists in China and Germany. The researchers believe their device is ready for use in a proposed gravitational wave search and might in future be used to find hypothetical dark matter particles.

Masers are the microwave-wavelength equivalent of lasers and their extreme frequency stability allows them to make invaluable contributions to atomic clocks, radio telescopes and several other areas of physics. In a traditional maser – as in a traditional laser – the masing action occurs between two energy levels in an atomic or molecular gain medium confined in a cavity. As electromagnetic radiation bounces back and forth in the cavity, photons whose frequency is resonant with the energy difference between the two levels are repeatedly emitted and absorbed by the atoms. Eventually, a “population inversion” with more atoms in the upper level is achieved, and stimulated emission from these atoms produces a highly monochromatic beam of microwave radiation.

Mar 14, 2021

Human-Safe Wormholes Could Exist in the Real World, Study Finds

Posted by in category: cosmology

Pack your bags. We’re going to another galaxy.

Mar 11, 2021

Origin of Solar-Mass Black Holes and the Connection to Dark Matter

Posted by in categories: cosmology, physics

What is the origin of black holes and how is that question connected with another mystery, the nature of dark matter? Dark matter comprises the majority of matter in the Universe, but its nature remains unknown.

Multiple gravitational wave detections of merging black holes have been identified within the last few years by the Laser Interferometer Gravitational-Wave Observatory (LIGO), commemorated with the 2017 physics Nobel Prize to Kip Thorne, Barry Barish, and Rainer Weiss. A definitive confirmation of the existence of black holes was celebrated with the 2020 physics Nobel Prize awarded to Andrea Ghez, Reinhard Genzel and Roger Penrose. Understanding the origin of black holes has thus emerged as a central issue in physics.

Surprisingly, LIGO has recently observed a 2.6 solar-mass black hole candidate (event GW190814, reported in Astrophysical Journal Letters 896 (2020) 2, L44). Assuming this is a black hole, and not an unusually massive neutron star, where does it come from?

Mar 11, 2021

Highest-Energy Cosmic Rays Detected in Star Clusters – Energies Beyond Those From Supernovae Capable of Devouring Entire Solar Systems

Posted by in categories: cosmology, particle physics

For decades, researchers assumed the cosmic rays that regularly bombard Earth from the far reaches of the galaxy are born when stars go supernova — when they grow too massive to support the fusion occurring at their cores and explode.

Those gigantic explosions do indeed propel atomic particles at the speed of light great distances. However, new research suggests even supernovae — capable of devouring entire solar systems — are not strong enough to imbue particles with the sustained energies needed to reach petaelectronvolts (PeVs), the amount of kinetic energy attained by very high-energy cosmic rays.

Continue reading “Highest-Energy Cosmic Rays Detected in Star Clusters – Energies Beyond Those From Supernovae Capable of Devouring Entire Solar Systems” »

Mar 11, 2021

Navy engineer devises new way to enhance night vision for ground forces

Posted by in categories: augmented reality, cosmology, economics, military, virtual reality

TOWARDS a METAMATERIALLY-BASED ANALOGUE SENSOR FOR TELESCOPE EYEPIECES jeremy batterson.

https://www.youtube.com/watch?v=rVQWmWkbzkw.

(NB: Those familiar with photography or telescopy can skip over the “elements of a system,” since they will already know this.)

Continue reading “Navy engineer devises new way to enhance night vision for ground forces” »

Mar 10, 2021

New Kind of Space Explosion Reveals the Birth of a Black Hole

Posted by in category: cosmology

A supernova-like explosion dubbed the Camel appears to be the result of a newborn black hole eating a star from the inside out.

Mar 9, 2021

Simulations of the Universe are Getting Better and Better at Matching Reality

Posted by in categories: cosmology, evolution, information science, physics

How can you possibly use simulations to reconstruct the history of the entire universe using only a small sample of galaxy observations? Through big data, that’s how.

Theoretically, we understand a lot of the physics of the history and evolution of the universe. We know that the universe used to be a lot smaller, denser, and hotter in the past. We know that its expansion is accelerating today. We know that the universe is made of very different things, including galaxies (which we can see) and dark matter (which we can’t).

We know that the largest structures in the universe have evolved slowly over time, starting as just small seeds and building up over billions of years through gravitational attraction.

Mar 8, 2021

Astronomers Have Discovered the Most Distant Source of Radio Emission Ever Known – 13 Billion Light-Years Away

Posted by in category: cosmology

With the help of the European Southern Observatory’s Very Large Telescope (ESO ’s VLT), astronomers have discovered and studied in detail the most distant source of radio emission known to date. The source is a “radio-loud” quasar — a bright object with powerful jets emitting at radio wavelengths — that is so far away its light has taken 13 billion years to reach us. The discovery could provide important clues to help astronomers understand the early Universe.

Quasars are very bright objects that lie at the center of some galaxies and are powered by supermassive black holes. As the black hole consumes the surrounding gas, energy is released, allowing astronomers to spot them even when they are very far away.

Continue reading “Astronomers Have Discovered the Most Distant Source of Radio Emission Ever Known – 13 Billion Light-Years Away” »

Mar 7, 2021

EROSITA X-Ray Telescope Spots Enormous Supernova Remnant | Astronomy

Posted by in category: cosmology

Astronomers using data from the eROSITA X-ray telescope aboard the Spektrum-Roentgen-Gamma (SRG) observatory have detected the largest supernova remnant ever discovered with X-rays.