Lifeboat Foundation

Today, the greatest mysteries facing astronomers and cosmologists are the roles gravitational attraction and cosmic expansion play in the evolution of the Universe.

To resolve these mysteries, astronomers and cosmologists are taking a two-pronged approach. These consist of directly observing the cosmos to observe these forces at work while attempting to find theoretical resolutions for observed behaviors – such as dark matter and dark energy.

In between these two approaches, scientists model cosmic evolution with computer simulations to see if observations align with theoretical predictions. The latest of which is AbacusSummit, a simulation suite created by the Flatiron Institute’s Center for Computational Astrophysics (CCA) and the Harvard-Smithsonian Center for Astrophysics (CfA).

How are chemical elements produced in our Universe? Where do heavy elements like gold and uranium come from? Using computer simulations, a research team from the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, together with colleagues from Belgium and Japan, shows that the synthesis of heavy elements is typical for certain black holes with orbiting matter accumulations, so-called accretion disks. The predicted abundance of the formed elements provides insight into which heavy elements need to be studied in future laboratories — such as the Facility for Antiproton and Ion Research (FAIR), which is currently under construction — to unravel the origin of heavy elements. The results are published in the journal Monthly Notices of the Royal Astronomical Society.

All heavy elements on Earth today were formed under extreme conditions in astrophysical environments: inside stars, in stellar explosions, and during the collision of neutron stars. Researchers are intrigued with the question in which of these astrophysical events the appropriate conditions for the formation of the heaviest elements, such as gold or uranium, exist. The spectacular first observation of gravitational waves and electromagnetic radiation originating from a neutron star merger in 2017 suggested that many heavy elements can be produced and released in these cosmic collisions. However, the question remains open as to when and why the material is ejected and whether there may be other scenarios in which heavy elements can be produced.

Promising candidates for heavy element production are black holes orbited by an accretion disk of dense and hot matter. Such a system is formed both after the merger of two massive neutron stars and during a so-called collapsar, the collapse and subsequent explosion of a rotating star. The internal composition of such accretion disks has so far not been well understood, particularly with respect to the conditions under which an excess of neutrons forms. A high number of neutrons is a basic requirement for the synthesis of heavy elements, as it enables the rapid neutron-capture process or r-process. Nearly massless neutrinos play a key role in this process, as they enable conversion between protons and neutrons.

A new model explains the current density of dark matter by proposing that conventional matter converted to dark matter in the early Universe.

There’s a lot we still don’t know about dark matter – that mysterious, invisible mass that could make up as much as 85 percent of everything around us – but a new paper outlines a rather unusual hypothesis about the very creation of the stuff.

In short: dark matter creates dark matter. The idea is that at some point in the early stages of the Universe, dark matter particles were able to create more dark matter particles out of particles of regular matter, which would go some way to explaining why there’s now so much of the stuff about.

The new research builds on earlier proposals of a ‘thermal bath’, where regular matter in the form of plasma produced the first bits of dark matter – initial particles which could then have had the power to transform heat bath particles into more dark matter.

Come out, come out, wherever you are!

In a neighboring star cluster called NGC 1,850, astronomers spotted a small black hole tugging on the orbit of a star — a discovery that could lead us to others.

O,.o circa 2014.

When we hear the term ‘parallel universe’, we often cite the classic science fiction picture of a parallel universe; something that acts as a mirror, where on one day, in this universe, you didn’t manage to have the guts to ask that girl out, but in the parallel universe, not only did ‘you’ ask her out, but a decade later, she became your wife. We all like to subscribe to such fascinating ideas, but for a while, it was relegated to the domain of sci-fi creators/fans. The real picture tells us something a lot more interesting.

AN INFINITE NUMBER OF ‘YOUS’;

Continue reading “Parallel Universes: An Infinite Number of Yous” »

Scientists have released the largest catalog of gravitational wave detections to date, shedding new light on interactions between the most massive objects in the universe, black holes and neutron stars.

The catalog was compiled by three groundbreaking detectors: the two Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors located in Hanford, Washington, and Livingston, Louisiana, and the European Virgo gravitational wave antenna in Pisa, Italy.

Scientists have recreated the first matter that appeared after the Big Bang in the Large Hadron Collider.

Of the cosmos’ four fundamental forces, gravity is the one that grasps us even before we exit the womb. From our first few minutes of life until we lose the fight to lift our heads from death’s pillow, this weakest of nature’s fundamental forces continues to elude researchers.

In the last few years, however, gravitational wave astronomy has made great strides in detecting gravitational radiation rippling through spacetime at the speed of light.

Einstein first predicted that any accelerating mass should emit gravitational radiation in the form of waves. Gravitational waves were first indirectly detected almost 20 years ago. But it was only recently, in 2,015 that the ground-based LIGO (Laser Interferometer Gravitational-wave Observatory) detected waves from two merging stellar mass black holes over a billion light years distant in the general direction of the Southern Hemisphere’s Magellanic Clouds.