БЛОГ

Archive for the ‘cosmology’ category: Page 406

Sep 5, 2015

Lessons From Dying Extrasolar Earths

Posted by in category: cosmology

For those who missed this.


By all counts, Earth is on a one way trip to oblivion. Our aging Sun will see to that. Within 500 to 900 million years from now, photosynthesis and plant life on Earth will reach a death-spiral tipping point as the Sun continues its normal expansion and increases in luminosity over time.

Trouble is, researchers are still unsure about all the grisly endgame details, and their models of such slow motion horrors are hard to test. But a team of researchers now say that finding and observing nearby aging Earth-analogues, undergoing the ravages of their own expanding sun-like stars, will help Earth scientists understand how the stellar evolution of our own sun will affect life here on Earth.

Continue reading “Lessons From Dying Extrasolar Earths” »

Sep 4, 2015

New General Relativity Area law theory suggests time runs backward inside a blackhole

Posted by in categories: cosmology, physics

Black holes are known to have many strange properties, such as that they allow nothing—not even light—to escape after falling in. A lesser known but equally bizarre property is that black holes appear to “know” what happens in the future in order to form in the first place. However, this strange property arises from the way in which black holes are defined, which has motivated some physicists to explore alternative definitions.

They reported a new area law in general relativity that is based on an interpretation of black holes as curved geometric objects called “holographic screens.”

“The so-called teleology of the black hole event horizon is an artifact of the way in which physicists define an event horizon: the event horizon is defined with respect to infinite future elapsed time, so by definition it ‘knows’ about the entire fate of the universe,” Engelhardt told Phys.org. “In general relativity, the black hole event horizon cannot be observed by any physical observer in finite time, and there isn’t a sense in which the black hole as an entity knows about future infinity. It is simply a convenient way of describing black holes.”

Read more

Sep 3, 2015

The Search For Elusive Gravitational Waves Is Headed to Space

Posted by in categories: cosmology, space

Great news. It’ll be fascinating to see what they discover.


In the distant reaches of the Universe, exploding stars and supermassive black holes are bending the very fabric of spacetime. It’s hard to wrap our brains around such tremendous forces, but we may be able to quantify them, in the form of gravitational waves. A new European Space Agency mission marks humanity’s first bold attempt to do so in outer space.

This fall, the ESA’s LISA Pathfinder will be blasted into space on a course for the L1 Lagrange point. Situated nearly a million miles from Earth, it’ll begin pilot-testing fundamental technologies for the detection of elusive gravitational waves. The miniature science observatory bid farewell to the public this week, on display at a test centre in Ottobrunn, Germany for the last time before its long journey.

A New Mission Will Search for Ripples in Spacetime

Read more

Aug 31, 2015

Double black hole is powering quasar, astronomers find

Posted by in categories: cosmology, space

Astronomers have discovered a galaxy is being powered by a quasar that contains two black holes whirling about each other.

Read more

Aug 25, 2015

Sci-Tech Universe: Black Holes are Escapable, Hawking Says

Posted by in category: cosmology

Matter that drops into a black hole is gone forever, right? Not so, declares Stephen Hawking.

Read more

Aug 25, 2015

Stephen Hawking believes he knows how information escapes black holes

Posted by in category: cosmology

Black holes may not be as inescapable as we once thought.

Read more

Aug 11, 2015

The Universe is Slowly Dying

Posted by in categories: cosmology, energy

Brace yourselves: winter is coming. And by winter I mean the slow heat-death of the Universe, and by brace yourselves I mean don’t get terribly concerned because the process will take a very, very, very long time. (But still, it’s coming.)

Based on findings from the Galaxy and Mass Assembly (GAMA) project, which used seven of the world’s most powerful telescopes to observe the sky in a wide array of electromagnetic wavelengths, the energy output of the nearby Universe (currently estimated to be ~13.82 billion years old) is currently half of what it was “only” 2 billion years ago — and it’s still decreasing.

“The Universe has basically plonked itself down on the sofa, pulled up a blanket and is about to nod off for an eternal doze,” said Professor Simon Driver from the International Centre for Radio Astronomy Research (ICRAR) in Western Australia, head of the nearly 100-member international research team.

Read more

Aug 11, 2015

Slow death of Universe confirmed with precision

Posted by in categories: astronomy, cosmology, gravity, physics, space
  • The universe radiates only half as much energy as 2 billion years ago
  • New findings establish cosmos’ decline with unprecedented precision


From CNN
—The universe came in with the biggest bang ever. But now, with a drooping fizzle, it is in its swan song. The conclusion of a new astronomical study pulls no punches on this: “The Universe is slowly dying,” it reads.

Astronomers have believed as much for years, but the new findings establish the cosmos’ decline with unprecedented precision. An international team of 100 scientists used data from the world’s most powerful telescopes — based on land and in space — to study energy coming from more than 200,000 galaxies in a large sliver of the observable universe. [Full story below or at CNN.com]…

Based on those observations, they have confirmed the cosmos is radiating only half as much energy as it was 2 billion years ago. The astronomers published their study on Monday on the website of the European Southern Observatory.

Analysis across many wavelengths shows the universe's electromagnetic energy output is dropping.The team checked the energy across a broad spectrum of lightwaves and other electromagnetic radiation and says it is fading through all wavelengths, from ultraviolet to far infrared.

Continue reading “Slow death of Universe confirmed with precision” »

Jul 28, 2015

How to Use a Black Hole’s Spin to Harvest Energy

Posted by in categories: cosmology, energy

A black hole isn’t the energy sink you might think it is. By hurling matter towards a black hole, it might be possible to get energy out of it. Learn how a spinning black hole could be an energy turbine for an entire civilization.

Read more

Jul 28, 2015

Astronomers Discover a New Class of Freakishly Dense, Compact Galaxies

Posted by in category: cosmology

Imagine what our night sky would look like if its stellar density was a million times greater than it is now. Remarkably, such places actually exist: They’re called “Ultracompact Dwarfs,” and astronomers are calling them an entirely new kind of galaxy.

Read more