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Archive for the ‘cosmology’ category: Page 305

Aug 12, 2019

Dark matter search yields technique for locating heavy metal seams

Posted by in categories: cosmology, particle physics, supercomputing

A method for locating seams of gold and other heavy metals is the unlikely spin-off of Swinburne’s involvement in a huge experiment to detect dark matter down a mine in Stawell, Victoria.

Associate Professor Alan Duffy, from Swinburne’s Centre for Astrophysics and Supercomputing and a member of the Sodium iodide with Active Background REjection (SABRE) project, said was effectively creating an X-ray of the Earth between the and the surface.

In the mine, the SABRE experiment seeks to detect particles of dark matter, something no one has conclusively achieved yet. Any signal from dark matter would be miniscule, and so the SABRE team created a phenomenally sensitive detector, which, it turns out, is also sensitive to a host of cosmic particles that can help us to locate gold.

Aug 12, 2019

Dark matter shock: Scientists speculate mystery substance predates the Big Bang

Posted by in category: cosmology

Dark matter most likely makes up an incredible 80 percent of the universe’s mass. But this single fact is the extent of our knowledge about this mysterious, all pervasive substance, with scientists unsure exactly what it is and how it came to be. Now a groundbreaking study has revealed dark matter may be even more bizarre than first thought, as its origin may have actually pre-dated the beginning of the Universe – the Big Bang.

Aug 12, 2019

Milky Way’s black hole has got 75 times brighter and we don’t know why

Posted by in category: cosmology

The supermassive black hole at the heart of our galaxy has suddenly started flashing brighter than we have ever seen it, and astronomers don’t know why.

Aug 11, 2019

Fractal Patterns Offer Clues to the Universe’s Origin

Posted by in categories: cosmology, futurism

Pour milk in coffee, and the eddies and tendrils of white soon fade to brown. In half an hour, the drink cools to room temperature. Left for days, the liquid evaporates. After centuries, the cup will disintegrate, and billions of years later, the entire planet, sun and solar system will disperse. Throughout the universe, all matter and energy is diffusing out of hot spots like coffee and stars, ultimately destined (after trillions of years) to spread uniformly through space. In other words, the same future awaits coffee and the cosmos.

This gradual spreading of matter and energy, called “thermalization,” aims the arrow of time. But the fact that time’s arrow is irreversible, so that hot coffee cools down but never spontaneously heats up, isn’t written into the underlying laws that govern the motion of the molecules in the coffee. Rather, thermalization is a statistical outcome: The coffee’s heat is far more likely to spread into the air than the cold air molecules are to concentrate energy into the coffee, just as shuffling a new deck of cards randomizes the cards’ order, and repeat shuffles will practically never re-sort them by suit and rank. Once coffee, cup and air reach thermal equilibrium, no more energy flows between them, and no further change occurs. Thus thermal equilibrium on a cosmic scale is dubbed the “heat death of the universe.”

But while it’s easy to see where thermalization leads (to tepid coffee and eventual heat death), it’s less obvious how the process begins. “If you start far from equilibrium, like in the early universe, how does the arrow of time emerge, starting from first principles?” said Jürgen Berges, a theoretical physicist at Heidelberg University in Germany who has studied this problem for more than a decade.

Aug 10, 2019

Radioactive Dust From an Ancient Supernova Is Buried in Antarctica

Posted by in category: cosmology

It was hidden in the snow.


The explosion happened at least 1.5 million years ago.

Aug 9, 2019

Virtual ‘universe machine’ sheds light on galaxy evolution

Posted by in categories: cosmology, evolution, supercomputing

How do galaxies such as our Milky Way come into existence? How do they grow and change over time? The science behind galaxy formation has remained a puzzle for decades, but a University of Arizona-led team of scientists is one step closer to finding answers thanks to supercomputer simulations.

Observing real galaxies in space can only provide snapshots in time, so researchers who want to study how galaxies evolve over billions of years have to revert to . Traditionally, astronomers have used this approach to invent and test new theories of , one-by-one. Peter Behroozi, an assistant professor at the UA Steward Observatory, and his team overcame this hurdle by generating millions of different universes on a supercomputer, each of which obeyed different physical theories for how galaxies should form.

The findings, published in the Monthly Notices of the Royal Astronomical Society, challenge fundamental ideas about the role dark matter plays in galaxy formation, how galaxies evolve over time and how they give birth to .

Aug 9, 2019

Fascinating New Study Claims Dark Matter May Be Older Than The Big Bang

Posted by in categories: cosmology, particle physics

Dark matter might well be the biggest mystery in the Universe. We know there’s something out there making things move faster than they should. But we don’t know what it is, and we sure as heck don’t know where it came from.

According to a new paper, the origins of dark matter may be more peculiar than we know. Perhaps, they were particles that appeared in a very brief period of time, just fractions of fractions of a second, before the Big Bang.

This doesn’t just suggest a new connection between particle physics and astronomy; if this hypothesis holds, it could indicate a new way to search for the mysterious stuff.

Aug 7, 2019

Big Bang theory wrong? Star older than Universe discovered — threat of ‘scientific crisis’

Posted by in category: cosmology

The Universe is thought to have popped into existence some 13.8 billion years ago when an infinitesimal point expanded billions of lightyears across in just a fraction of a second. The Big Bang theory has stood for the best part of 100 years after Belgian physicist Georges Lemaître first proposed in 1927 the expansion of the Universe could be traced back to a single point. However, the well-accepted model is now under the microscope after a team of researchers found a star which appears to be older than the cosmos.

Aug 6, 2019

Astronomers Just Found an Absolutely Gargantuan Black Hole The Mass of 40 Billion Suns

Posted by in category: cosmology

Black holes can get pretty big, but there’s a special class that is the biggest of the big, absolute yawning monster black holes. And astronomers seem to have found an absolute specimen, clocking in at 40 billion times the mass of the Sun.

It’s at the centre of a galaxy called Holmberg 15A, a supergiant elliptical galaxy around 700 million light-years away, which in turn sits at the centre of the Abell 85 galaxy cluster.

The object is one of the biggest black holes ever found, and the biggest found by tracking the movement of the stars around it.

Aug 5, 2019

We contain microbes so deeply weird they alter the very tree of life

Posted by in categories: biological, cosmology, health

Newly discovered life forms inside our bodies profoundly affect our health – and provide a glimpse of the vast and mysterious biological “dark matter” within us.