Archive for the ‘cosmology’ category: Page 384
Aug 8, 2016
Tunnels in spacetime could someday take us to another universe, claims radical theory
Posted by Andreas Matt in categories: cosmology, space travel
But, using an assumption that a wormhole can be found at the middle of a black hole, a group of Portugese researchers modelled how objects like a chair, a scientist and a spacecraft would be able to withstand the journey through it.
‘What we did was to reconsider a fundamental question on the relation between the gravity and the underlying structure of space-time,’ Diego Rubiera-Garcia, lead author from the University of Lisbon, Portugal, said.
Two analyses indicate that LIGO could have detected black holes that formed just after the Big Bang.
Aug 3, 2016
Elusive neutrinos and hypothetical ‘dark sector’ particles could hold answers to cosmic mysteries
Posted by Andreas Matt in categories: cosmology, particle physics
All material things appear to be made of elementary particles that are held together by fundamental forces. But what are their exact properties? How do they affect how our universe looks and changes? And are there particles and forces that we don’t know of yet?
Questions with cosmic implications like these drive many of the scientific efforts at the Department of Energy’s SLAC National Accelerator Laboratory. Three distinguished particle physicists have joined the lab over the past months to pursue research on two particularly mysterious forms of matter: neutrinos and dark matter.
Neutrinos, which are abundantly produced in nuclear reactions, are among the most common types of particles in the universe. Although they were discovered 60 years ago, their basic properties puzzle scientists to this date.
Somewhere, in the deepest reaches of the cosmos, far from the safe confines of our home galaxy, the Milky Way, lies a monster. Slowly, inevitably, it is pulling. Over the course of billions of years, it draws us and everything near us closer to it. The only force that acts over such immense distance scales and through cosmic periods of time is gravity, so whatever it is, it’s massive and unrelenting.
We call it the Great Attractor, and until recently, its true nature has been a complete mystery. Note that it’s still a mystery, just not a complete one.
The Great Attractor was first discovered in the 1970s when astronomers made detailed maps of the Cosmic Microwave Background (the light left over from the early universe), and noticed that it was slightly (and “slightly” here means less than one one-hundredth of a degree Fahrenheit) warmer on one side of the Milky Way than the other — implying that the galaxy was moving through space at the brisk clip of about 370 miles per second (600 km/s).
Even though astronomers could measure the rapid velocity, they couldn’t explain its origin.
Jul 28, 2016
Could Dark Energy Be Caused By A Reaction To What’s In The Universe? (Synopsis)
Posted by Karen Hurst in categories: cosmology, particle physics, quantum physics
“Another very good test some readers may want to look up… is the Casimir effect, where forces between metal plates in empty space are modified by the presence of virtual particles.” –Gordon Kane
If you ask what the zero-point energy of space itself is, you can sum up all of the quantum fluctuations you can that arise in quantum field theory, and arrive at an absurd answer: 120 orders of magnitude greater than the observed. Yet if you assume that there’s an incredible cancellation and you get exactly zero, that removes the one thing our Universe needs to explain its expansion: dark energy.
Jul 27, 2016
Did the LIGO gravitational waves originate from primordial black holes?
Posted by Andreas Matt in categories: cosmology, physics
Binary black holes recently discovered by the LIGO-Virgo collaboration could be primordial entities that formed just after the Big Bang, report Japanese astrophysicists.
If further data support this observation, it could mark the first confirmed finding of a primordial black hole, guiding theories about the beginnings of the universe.
In February, the LIGO-Virgo collaboration announced the first successful detection of gravitational waves.
Continue reading “Did the LIGO gravitational waves originate from primordial black holes?” »
Jul 25, 2016
Astronomers Find Black Holes Do Not Absorb Dark Matter
Posted by Andreas Matt in categories: cosmology, materials
There’s the common notion that black holes suck in everything in the nearby vicinity by exerting a strong gravitational influence on the matter, energy, and space surrounding them. But astronomers have found that the dark matter around black holes might be a different story. Somehow dark matter resists ‘assimilation’ into a black hole.
About 23% of the Universe is made up of mysterious dark matter, invisible material only detected through its gravitational influence on its surroundings. In the early Universe clumps of dark matter are thought to have attracted gas, which then coalesced into stars that eventually assembled the galaxies we see today. In their efforts to understand galaxy formation and evolution, astronomers have spent a good deal of time attempting to simulate the build up of dark matter in these objects.
Jul 23, 2016
Ask Ethan: Will The ‘Great Attractor’ Defeat Dark Energy?
Posted by Sean Brazell in category: cosmology
Can the thousands of galaxies tugging on us eventually pull our little group of galaxies into it?
Jul 22, 2016
Another dark matter search comes up empty
Posted by Aleksandar Vukovic in category: cosmology
Even though dark matter has not yet been found, scientists are confident it exists as its effects can be seen in the rotation of galaxies and the bending of light as it makes its way through the universe.
The Large Underground Xenon (LUX) dark matter experiment has found no traces of dark matter.