Archive for the ‘cosmology’ category: Page 400
Jul 21, 2016
The Allegory of the Cave
Posted by Karen Hurst in categories: cosmology, quantum physics
Inspired by the Allegory of the Cave from Plato, till today’s quantum physics and multiverse theories, a visual essay about perception and knowledge as reflection of our reality.
Jul 20, 2016
Physicists Say They’ve Figured out How Spacecraft Could Make It Through a Wormhole
Posted by Andreas Matt in categories: climatology, cosmology, physics, space travel, sustainability
A new paper asserts that a physical body might be able to pass through a wormhole in spite of the extreme tidal forces that are at play.
A physical object, such as a person or a spacecraft, could theoretically make it through a wormhole in the centre of a black hole, and maybe even access another universe on the other side, physicists have suggested.
Tl;dr: Yes, but it’s unlikely.
If black holes attract your attention, white holes might blow your mind.
A white hole is a time-reversed black hole, an anti-collapse. While a black hole contains a region from which nothing can escape, a white hole contains a region to which nothing can fall in. Since the time-reversal of a solution of General Relativity is another solution, we know that white holes exist mathematically. But are they real?
Jul 12, 2016
No Big Bang –“Our Universe Was Formed From an Older Collapsing Universe”
Posted by Karen Hurst in categories: cosmology, materials
A new study of the early universe reveals how it could have been formed from an older collapsing universe, rather than being brand new. The universe is currently expanding and it is a common theory that this is the result of the ‘Big Bang’ – the universe bursting into existence from a point of infinitely dense and hot material.
Jul 11, 2016
‘Crowd Control,’ part 22: Spies in heaven
Posted by Zoltan Istvan in categories: cosmology, geopolitics, transhumanism
The final chapter in CNET’s historic “crowdsourced” sci-fi novel is out. You can read the whole thing here. Transhumanism is a large part of it (and a fictional version of my being President is in it too). This book was written by the participating public. This was a huge plus for the Transhumanist movement, as it meant transhumanism appeared many times on CNET as chapters were released (CNET is the world’s leading tech site in traffic):
In the finale of CNET’s historic crowdsourced sci-fi novel, the war on Earth is over, but the story of the multiverse may just be getting started.
Jul 11, 2016
Our universe could be reborn as a bouncing baby cosmos
Posted by Karen Hurst in categories: cosmology, physics
A new model shows how the universe could survive a “big bounce” rather than a big bang, without the need for complex new physics.
Jul 9, 2016
NASA’s ‘Dark Matter’ Probe: “Our Milky Way Galaxy is Embedded Within a Vast Sphere of Black Holes” (Weekend Feature)
Posted by Andreas Matt in category: cosmology
“All galaxies, including our own, are embedded within a vast sphere of black holes each about 30 times the sun’s mass,” says Alexander Kashlinsky, an astrophysicist at NASA’s Goddard Space Flight Center.
Jul 8, 2016
Could the Big Bang have been more of a Big Bounce?
Posted by Karen Hurst in categories: cosmology, particle physics, quantum physics
When the bang became a bounce.
How the universe began is one of the most brain-breaking questions you could possibly ask, and the Big Bang is probably the answer most people accept. But what if the infinitely dense point from which the entire universe burst forth wasn’t the beginning of everything, but merely the middle of an ongoing cycle? That’s the theory of the Big Bounce, which suggests that the universe regularly cycles through periods of expansion and contraction, meaning the Big Bang may have been preceded by an earlier universe collapsing in on itself. A new study details how this might be possible.
The idea of the Big Bounce has been bouncing around since 1922, but explaining just how the universe transitions between expanding and contracting has always been an issue. What’s to stop a universe just contracting into a point and collapsing completely? According to researchers from Imperial College London and the Perimeter Institute for Theoretical Physics in Canada, it may be the same quantum mechanics that prevent atoms from deteriorating into nothing.
Continue reading “Could the Big Bang have been more of a Big Bounce?” »
Jul 8, 2016
Extra dimensions, gravitons, and tiny black holes
Posted by Andreas Matt in categories: cosmology, particle physics
Why is gravity so much weaker than the other fundamental forces? A small fridge magnet is enough to create an electromagnetic force greater than the gravitational pull exerted by planet Earth. One possibility is that we don’t feel the full effect of gravity because part of it spreads to extra dimensions. Though it may sound like science fiction, if extra dimensions exist, they could explain why the universe is expanding faster than expected, and why gravity is weaker than the other forces of nature.
In our everyday lives, we experience three spatial dimensions, and a fourth dimension of time. How could there be more? Einstein’s general theory of relativity tells us that space can expand, contract, and bend. Now if one dimension were to contract to a size smaller than an atom, it would be hidden from our view. But if we could look on a small enough scale, that hidden dimension might become visible again. Imagine a person walking on a tightrope. She can only move backward and forward; but not left and right, nor up and down, so she only sees one dimension. Ants living on a much smaller scale could move around the cable, in what would appear like an extra dimension to the tightrope-walker.