The breakthrough on June 21st has brought many positive developments.The amount of still present plasma toplet bombs is slowly but steadily decreasing, and the following scenario with toplets bombs detonating now seems extremely unlikely:https://www.da...
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Rats were even more likely to choose helping over getting a treat
Excerpt from cbc.ca
Calling someone a rat isn't a compliment about their character – but a new study suggests that maybe it should be.
Rats that see another rat struggling in a pool of water will open a door to rescue it, even if they could open a different door to get a chocolate treat instead.
Rats that knew what it was like to be wet and struggling in the pool were even quicker to help.
"Our findings suggest that rats can behave prosocially and that helper rats may be motivated by empathy-like feelings towards their distressed cage mate," Nobuya Sato, lead author of a study, said in a statement.
The study was published this week in the journal Animal Cognition.
Sato and his team at Kwansei Gakuin University in Japan designed experiments involving pairs of rat cage mates, either two males or two females.
The two were placed in separate compartments separated by a transparent wall and door – one compartment that was dry and empty, and one filled with a deep pool of water and sheer walls that made it impossible to climb out. The door could be opened by the rat on the dry side, allowing the other rat to climb out of the pool.
The researchers reversed the roles and found that rats were quicker to learn to open the door and rescue their cage mate if they had previously experienced a similar struggle in the pool.
"This modulation of learning by prior experience suggests that the helping behaviour observed in the present study might be based on empathy," they wrote.
In another experiment, rats in the dry compartment could choose between two different doors.
"These results suggest that for all rats, helping a distressed cage mate has a higher value than obtaining a food reward," the researchers wrote.
The results are similar to those in a previous experiment by different researchers, in which rats rescued other rats trapped in an acrylic tube. Still, there has some debate about whether this type of helping behaviour exists among animals other than primates such as monkeys and humans.
Rats that see another rat struggling in a pool of water will open a door to rescue it, even if they could open a different door to get a chocolate treat instead.
Rats that knew what it was like to be wet and struggling in the pool were even quicker to help.
"Our findings suggest that rats can behave prosocially and that helper rats may be motivated by empathy-like feelings towards their distressed cage mate," Nobuya Sato, lead author of a study, said in a statement.
The study was published this week in the journal Animal Cognition.
Sato and his team at Kwansei Gakuin University in Japan designed experiments involving pairs of rat cage mates, either two males or two females.
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| 'Helper rats may be motivated by empathy-like feelings,' suggests Nobuya Sato, a Kwansei Gakuin University in Japan research and lead author of a study released this week. (Andre Penner/Associated Press) |
The two were placed in separate compartments separated by a transparent wall and door – one compartment that was dry and empty, and one filled with a deep pool of water and sheer walls that made it impossible to climb out. The door could be opened by the rat on the dry side, allowing the other rat to climb out of the pool.
Motivated by helping
Rats on the dry side of the cage were quick to open the door if they saw their cage mates struggling in the water, but not if the pool was empty or contained a stuffed toy rat. If no water was in either compartment, they also didn't open the door. That suggested that they were motivated by helping and not just opening the door for fun.The researchers reversed the roles and found that rats were quicker to learn to open the door and rescue their cage mate if they had previously experienced a similar struggle in the pool.
"This modulation of learning by prior experience suggests that the helping behaviour observed in the present study might be based on empathy," they wrote.
In another experiment, rats in the dry compartment could choose between two different doors.
- One that allowed them to rescue their cage mate from the pool.
- Another that provided access to a chocolate cereal treat.
"These results suggest that for all rats, helping a distressed cage mate has a higher value than obtaining a food reward," the researchers wrote.
The results are similar to those in a previous experiment by different researchers, in which rats rescued other rats trapped in an acrylic tube. Still, there has some debate about whether this type of helping behaviour exists among animals other than primates such as monkeys and humans.
Excerpt from huffingtonpost.comIntroductionWhy is it so hard to find ET? After 50 years of searching, the SETI project has so far found nothing. In the latest development, on April 14, 2015 Penn State researchers announced that after searching through...
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| It now seems more probable that a collision between two planets of similar composition led to the formation of the Moon. |
Excerpt from nature.com
A nagging problem at the heart of the leading theory of how the Moon formed seems to have been explained away.
But the theory also implies that the Moon is made up mostly of impactor material. Since lunar and Earth rocks have such similar compositions, this suggests that Earth and the planet that smacked into it resembled each other too. They would have needed to be sister planets, with a relationship much closer than that of any other planetary bodies we have studied in our Solar System. The odds of this being possible were thought to be around a 1% chance, or “uncomfortably rare”, according to Robin Canup, a planetary researcher at the Southwest Research Institute in Boulder, Colorado1.
Better odds
Now it seems that the scenario is not so far-fetched, says Hagai Perets, an astrophysicist at the Israel Institute of Technology in Haifa. He and his colleagues performed simulations of the Solar System’s formation, to investigate how similar planets tend to be to their last giant impactor. They estimated that for 20% to 40% of collisions, the two bodies would be sufficiently similar to explain the Moon’s composition — considerably better odds. The findings are published in Nature2.The planets would have closely resembled each other because of their similar distance from the Sun, meaning that they would have formed from the same kind of orbiting proto-planetary material. “The Earth and the Moon are not twins born from the same planet, but they are sisters in the sense that they grew up in the same environment,” says Perets.
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| Nova Vulpeculae 1670 |
Excerpt from thespacereporter.com
A mystery explosion in the night sky turns out to have been caused by colliding stars.
One of history’s mysteries revolved around a strange explosion observed in the sky in 1670, long thought to have been the first nova on record. Recent research suggests that this enigmatic event was actually a rare stellar collision.
According to a report by Astronomy Magazine, the so-called Nova Vulpeculae of 1670 was more likely the collision of two stars, which shines brighter than a nova but not as brightly as a supernova.
Observations made with various telescopes including the Submillimeter Array, the Effelsburg radio telescope and APEX have revealed the more unusual nature of the light source – a violent collision.
When the event first occurred, it would have been visible from Earth with the naked eye. Now, submillimeter telescopes are needed to detect the traces left in the aftermath of the event.
When first observed, 17th century astronomers described what they saw as a new star appearing in the head of Cygnus, the swan constellation.
Having observed the area of the supposed nova with both submillimeter and radio wavelengths, scientists “have found that the surroundings of the remnant are bathed in a cool gas rich in molecules with a very unusual chemical composition,” said Kaminski.
Researchers concluded that the amount of cool material they observed was too much to have been produced by a nova. The nature of the gas debris best fit with the rare scenario of two stars merging in an explosive collision.
The team’s report was published in the journal Nature.
Karl Menten of the Max Planck Institute called the discovery “the most fun – something that is completely unexpected.”
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| (Photo : NASA/ESA) In early days of solar system, Jupiter destroyed everything that came in its way, researchers have found. |
Excerpt from latimes.com
Before Mercury, Venus, Earth and Mars occupied the inner solar system, there may have been a previous generation of planets that were bigger and more numerous – but were ultimately doomed by Jupiter, according to a new study.
If indeed the early solar system was crowded with so-called super-Earths, it would have looked a lot more like the planetary systems found elsewhere in the galaxy, scientists wrote Monday in the Proceedings of the National Academy of Sciences.
As NASA’s Kepler space telescope has found more than 1,000 planets in orbit around other stars, along with more than 4,000 other objects that are believed to be planets but haven’t yet been confirmed. Kepler finds these planets by watching their host stars and registering tiny drops in their brightness – a sign that they are being ever-so-slightly darkened by a planet crossing in front of them.
In addition, ground-based telescopes have detected hundreds of exoplanets by measuring the wiggles of distant stars. Those stars wiggle thanks to the gravitational pull of orbiting planets, and the Doppler effect makes it possible to estimate the size of these planets.
The more planetary systems astronomers discovered, the more our own solar system looked like an oddball. Exoplanets – at least the ones big enough for us to see – tended to be bigger than Earth, with tight orbits that took them much closer to their host stars. In multi-planet systems, these orbits tended to be much closer together than they are in our solar system. For instance, the star known as Kepler-11 has six planets closer to it than Venus is to the sun.
Why does our solar system look so different? Astrophysicists Konstantin Batygin of Caltech and Greg Laughlin of UC Santa Cruz summed it up in one word: Jupiter.
Here’s what could have happened, according to their models:
In Solar System 1.0, the region closest to the sun was occupied by numerous planets with masses several times bigger than that of Earth. There were also planetesimals, “planetary building blocks” that formed within the first million years after the birth of the sun, Batygin and Laughlin wrote.
This is how things might have stayed if the young Jupiter had stayed put at its initial orbit, between 3 and 10 astronomical units away from the sun. (An astronomical unit, or AU, is the distance between the Earth and the sun. Today, Jupiter’s orbit ranges between 5 and 5.5 AUs from the sun.)
But Jupiter was restless, according to a scenario known as the “Grand Tack.” In this version of events, Jupiter was swept up by the currents of gas that surrounded the young sun and drifted toward the center of the solar system.
Jupiter, however, was too big to travel solo. All manner of smaller objects would have been dragged along too. With so many bodies in motion, there would have been a lot of crashes.
The result was “a collisional cascade that grinds down the planetesimal population to smaller sizes,” the astrophysicists wrote. For the most part, these planetary crumbs were swept toward the sun and ultimately destroyed, like disintegrating satellites falling back to Earth.
The planetesimals wouldn’t have been Jupiter’s only victims. Assuming the early solar system resembled the planetary systems spied by Kepler and other telescopes, there would have been “a similar population of first-generation planets,” the pair wrote. “If such planets formed, however, they were destroyed.”
Jupiter probably got about as close to the sun as Mars is today before reversing course, pulled away by the gravity of the newly formed Saturn. That would have ended the chaos in the inner solar system, allowing Earth and the other rocky planets to form from the debris that remained.
“This scenario provides a natural explanation for why the inner Solar System bears scant resemblance to the ubiquitous multi-planet systems” discovered by Kepler and other survey efforts, Batygin and Laughlin wrote.
Although their models show that this is what might have happened, they don’t prove that it actually did. But there may be a way to get closer to the truth.
The scientists’ equations suggest that if a star is orbited by a cluster of close-in planets, there won’t be a larger, farther-out planet in the same system. As astronomers find more exoplanetary systems, they can see whether this prediction holds up.
Also, if far-away solar systems are experiencing a similar series of events, telescopes ought to be able to detect the extra heat thrown off by all of the planetesimal collisions, they added.
Sadly for those hoping to find life on other planets, the pair’s calculations also imply that most Earth-sized planets are lacking in water and other essential compounds that can exist in liquid or solid form. As a result, they would be “uninhabitable,” they wrote.
Excerpt from cnbc.com
By Susan Caminiti
Moon Express, a Mountain View, California-based company that's aiming to send the first commercial robotic spacecraft to the moon next year, just took another step closer toward that lofty goal.
Earlier this year, it became the first company to successfully test a prototype of a lunar lander at the Kennedy Space Center in Florida. The success of this test—and a series of others that will take place later this year—paves the way for Moon Express to send its lander to the moon in 2016, said company co-founder and chairman Naveen Jain.
Earlier this year, it became the first company to successfully test a prototype of a lunar lander at the Kennedy Space Center in Florida. The success of this test—and a series of others that will take place later this year—paves the way for Moon Express to send its lander to the moon in 2016, said company co-founder and chairman Naveen Jain.
Moon Express conducted its tests with the support of NASA engineers, who are sharing with the company their deep well of lunar know-how. The NASA lunar initiative—known as Catalyst—is designed to spur new commercial U.S. capabilities to reach the moon and tap into its considerable resources.In addition to Moon Express, NASA is also working with Astrobotic Technologies of Pittsburgh, Pennsylvania, and Masten Space Systems of Mojave, California, to develop commercial robotic spacecrafts.
Jain said Moon Express also recently signed an agreement to take over Space Launch Complex 36 at Cape Canaveral. The historic launchpad will be used for Moon Express's lander development and flight-test operations. Before it was decommissioned, the launchpad was home to NASA's Atlas-Centaur rocket program and its Surveyor moon landers.
"Clearly, NASA has an amazing amount of expertise when it comes to getting to the moon, and it wants to pass that knowledge on to a company like ours that has the best chance of being successful," said Jain, a serial entrepreneur who also founded Internet companies Infospace and Intelius. He believes that the moon holds precious metals and rare minerals that can be brought back to help address Earth's energy, health and resource challenges.
Among the moon's vast riches: gold, cobalt, iron, palladium, platinum, tungsten and Helium-3, a gas that can be used in future fusion reactors to provide nuclear power without radioactive waste. "We went to the moon 50 years ago, yet today we have more computing power with our iPhones than the computers that sent men into space," Jain said. "That type of exponential technological growth is allowing things to happen that was never possible before."
Jain said Moon Express also recently signed an agreement to take over Space Launch Complex 36 at Cape Canaveral. The historic launchpad will be used for Moon Express's lander development and flight-test operations. Before it was decommissioned, the launchpad was home to NASA's Atlas-Centaur rocket program and its Surveyor moon landers.
"Clearly, NASA has an amazing amount of expertise when it comes to getting to the moon, and it wants to pass that knowledge on to a company like ours that has the best chance of being successful," said Jain, a serial entrepreneur who also founded Internet companies Infospace and Intelius. He believes that the moon holds precious metals and rare minerals that can be brought back to help address Earth's energy, health and resource challenges.
Among the moon's vast riches: gold, cobalt, iron, palladium, platinum, tungsten and Helium-3, a gas that can be used in future fusion reactors to provide nuclear power without radioactive waste. "We went to the moon 50 years ago, yet today we have more computing power with our iPhones than the computers that sent men into space," Jain said. "That type of exponential technological growth is allowing things to happen that was never possible before."
An eye on the Google prize
Source: MoonExpress
Helping to drive this newfound interest in privately funded space exploration is the Google Lunar X Prize. It's a competition organized by the X Prize Foundation and sponsored by Google that will award $30 million to the first company that lands a commercial spacecraft on the moon, travels 500 meters across its surface and sends high-definition images and video back to Earth—all before the end of 2016.
Moon Express is already at the front of the pack. In January it was awarded a $1 million milestone prize from Google for being the only company in the competition so far to test a prototype of its lander. "Winning the X prize would be a great thing," said Jain. "But building a great company is the ultimate goal with us." When it comes to space exploration, he added, "it's clear that the baton has been passed from the government to the private sector."
Testing in stages
Jain said Moon Express has been putting its lunar lander through a series of tests at the space center. The successful outing earlier this year involved tethering the vehicle—which is the size of a coffee table—to a crane in order to safely test its control systems. "The reason we tethered it to the crane is because the last thing we wanted was the aircraft to go completely haywire and hurt someone," he said.At the end of March, the company will conduct a completely free flight test with no tethering. The lander will take off from the pad, go up and sideways, then land back at the launchpad. "This is to test that the vehicle knows where to go and how to get back to the launchpad safely," Jain explained.
Once all these tests are successfully completed, Jain said the lander—called MX-1—will be ready to travel to the moon. The most likely scenario is that it will be attached to a satellite that will take the lander into a low orbit over the Earth. From there the MX-1 will fire its own rocket, powered by hydrogen peroxide, and launch from that orbit to complete its travel to the moon's surface.
The lander's first mission is a one-way trip, meaning that it's not designed to travel back to the Earth, said Jain. "The purpose is to show that for the first time, a company has developed the technology to land softly on the moon," he said. "Landing on the moon is not the hard part. Landing softly is the hard part."
That's because even though the gravity of the moon is one-sixth that of the Earth's, the lander will still be traveling down to the surface of the moon "like a bullet," Jain explained. Without the right calculations to indicate when its rockets have to fire in order to slow it down, the lander would hit the surface of the moon and break into millions of pieces. "Unlike here on Earth, there's no GPS on the moon to tell us this, so we have to do all these calculations first," he said.
Looking ahead 15 or 20 years, Jain said he envisions a day when the moon is used as a sort of way station enabling easier travel for exploration to other planets. In the meantime, he said the lander's second and third missions could likely involve bringing precious metals, minerals and even moon rocks back to Earth. "Today, people look at diamonds as this rare thing on Earth," Jain said.
He added, "Imagine telling someone you love her by giving her the moon."
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| Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society. |
Excerpt from news.discovery.com
This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.
Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.
The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.
In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.
“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”
Camargo’s team published their results in the journal Monthly
Excerpt space.com
A strange set of 48 galaxies appears to be rich in dark matter and lacking in stars, suggesting that they may be so-called "failed" galaxies, a new study reports.
The galaxies in question are part of the Coma Cluster, which lies 300 million light-years from Earth and packs several thousand galaxies into a space just 20 million light-years across. To study them, Pieter van Dokkum of Yale University and his colleagues used the Dragonfly Telephoto Array in New Mexico.
The array's eight connected Canon telephoto lenses allow the researchers to search for extremely faint objects that traditional telescope surveys miss. Often, such as when the researchers used the array to search for the faint glow that dark matter might create, the hunt comes up empty.
But when van Dokkum and his colleagues looked toward the Coma Cluster, they found a pleasant surprise.
"We noticed all these faint little smudges in the images from the Dragonfly telescope," van Dokkum told Space.com.
The mysterious blobs nagged at van Dokkum, compelling him to look into the objects further. Fortuitously, NASA's Hubble Space Telescope had recently captured one of these objects with its sharp eye.
"It turned out that they're these fuzzy blobs that look somewhat like dwarf spheroidal galaxies around our own Milky Way," van Dokkum said. "So they looked familiar in some sense … except that if they are at the distance of the Coma Cluster, they must be really huge."
And with very few stars to account for the mass in these galaxies, they must contain huge amounts of dark matter, the researchers said. In fact, to stay intact, the 48 galaxies must contain 98 percent dark matter and just 2 percent "normal" matter that we can see. The fraction of dark matter in the universe as a whole is thought to be around 83 percent.
But before making this claim, the team had to verify that these blobs really are as distant as the Coma Cluster. (In fact, the team initially thought the galaxies were much closer.). But even in the Hubble image the stars were not resolved. If Hubble — one of the most powerful telescopes in existence — can't resolve the stars, those pinpricks of light must be pretty far away, study team members reasoned.
Now, van Dokkum and his colleagues have definitive evidence: They've determined the exact distance to one of the galaxies. The team used the Keck Telescope in Hawaii to look at one of the objects for two hours. This gave them a hazy spectrum, from which they were able to tease out the galaxy's recessional velocity — that is, how fast it is moving away from Earth.
That measure traces back to the Hubble Telescope's namesake. In 1929, American astronomer Edwin Hubble discovered one of the simplest and most surprising relationships in astronomy: The more distant a galaxy, the faster it moves away from the Milky Way.
Today, astronomers use the relationship to measure a galaxy's recessional velocity and thus calculate the galaxy's distance. In this case, the small fuzzy blob observed with Keck was moving away from Earth at 15.7 million mph (25.3 million km/h). That places it at 300 million light-years away from Earth, the distance of the Coma Cluster.
So the verdict is officially in: These galaxies must be associated with the Coma Cluster and therefore must be extremely massive.
"It looks like the universe is able to make unexpected galaxies," van Dokkum said, adding that there is an amazing diversity of massive galaxies.
But the clusters still present a mystery: The team doesn't know why they have so much dark matter and so few stars.
Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz.
Normally, the galaxy has such a strong gravitational pull that most of the expelled gas falls back onto the galaxy and forms the next generations of stars. But maybe the strong gravitational pull of the other galaxies in the Coma Cluster interfered with this process, pulling the gas away.
"If that happened, they had no more fuel for star formation and they were sort of stillborn galaxies where they started to get going but then failed to really build up a lot of stars," said van Dokkum, adding that this is the most likely scenario.
Another possibility is that these galaxies are in the process of being ripped apart. But astronomers expect that if this were the case, the galaxies would be distorted and streams of stars would be flowing away from them. Because these effects don't appear, this scenario is very unlikely.
The next step is to try to measure the individual motions of stars within the galaxies. If the team knew those stars' speeds, it could calculate the galaxies' exact mass, and therefore the amount of dark matter they contain. If the stars move faster, the galaxy is more massive. And if they move slower, the galaxy is less massive.
However, this would require a better spectrum than the one the team has right now.
"But it's not outside the realm of what's possible," van Dokkum assured. "It's just very hard."
The original study has been published in Astrophysical Journal Letters. You can read it for free on the preprint site arXiv.org.
Scholz's star - shown in this artist's impression - is currently 20 light-years away. But it once came much closerExcerpt from bbc.comAn alien star passed through our Solar System just 70,000 years ago, astronomers have discovered. No othe...
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At the center of spiral galaxy M81 is a supermassive black hole about 70 million times more massive than our sun. |
Excerpt from insidescience.org
A physicist presents a solution to present-day cosmic mysteries.
By:
Nikodem Poplawski, Inside Science Minds Guest Columnist
(ISM) -- Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself.
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible "singularity," an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.
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| In this picture, spins in particles interact with spacetime and endow it with a property called "torsion." To understand torsion, imagine spacetime not as a two-dimensional canvas, but as a flexible, one-dimensional rod. Bending the rod corresponds to curving spacetime, and twisting the rod corresponds to spacetime torsion. If a rod is thin, you can bend it, but it's hard to see if it's twisted or not. |
The first is general relativity, the modern theory of gravity. It describes the universe at the largest scales. Any event in the universe occurs as a point in space and time, or spacetime. A massive object such as the Sun distorts or "curves" spacetime, like a bowling ball sitting on a canvas. The Sun's gravitational dent alters the motion of Earth and the other planets orbiting it. The sun's pull of the planets appears to us as the force of gravity.
The second is quantum mechanics, which describes the universe at the smallest scales, such as the level of the atom. However, quantum mechanics and general relativity are currently separate theories; physicists have been striving to combine the two successfully into a single theory of "quantum gravity" to adequately describe important phenomena, including the behavior of subatomic particles in black holes.
A 1960s adaptation of general relativity, called the Einstein-Cartan-Sciama-Kibble theory of gravity, takes into account effects from quantum mechanics. It not only provides a step towards quantum gravity but also leads to an alternative picture of the universe. This variation of general relativity incorporates an important quantum property known as spin. Particles such as atoms and electrons possess spin, or the internal angular momentum that is analogous to a skater spinning on ice.
Spacetime torsion would only be significant, let alone noticeable, in the early universe or in black holes. In these extreme environments, spacetime torsion would manifest itself as a repulsive force that counters the attractive gravitational force coming from spacetime curvature. As in the standard version of general relativity, very massive stars end up collapsing into black holes: regions of space from which nothing, not even light, can escape.
Here is how torsion would play out in the beginning moments of our universe. Initially, the gravitational attraction from curved space would overcome torsion's repulsive forces, serving to collapse matter into smaller regions of space. But eventually torsion would become very strong and prevent matter from compressing into a point of infinite density; matter would reach a state of extremely large but finite density. As energy can be converted into mass, the immensely high gravitational energy in this extremely dense state would cause an intense production of particles, greatly increasing the mass inside the black hole.
The increasing numbers of particles with spin would result in higher levels of spacetime torsion. The repulsive torsion would stop the collapse and would create a "big bounce" like a compressed beach ball that snaps outward. The rapid recoil after such a big bounce could be what has led to our expanding universe. The result of this recoil matches observations of the universe's shape, geometry, and distribution of mass.
In turn, the torsion mechanism suggests an astonishing scenario: every black hole would produce a new, baby universe inside. If that is true, then the first matter in our universe came from somewhere else. So our own universe could be the interior of a black hole existing in another universe. Just as we cannot see what is going on inside black holes in the cosmos, any observers in the parent universe could not see what is going on in ours.
The motion of matter through the black hole's boundary, called an "event horizon," would only happen in one direction, providing a direction of time that we perceive as moving forward. The arrow of time in our universe would therefore be inherited, through torsion, from the parent universe.
Torsion could also explain the observed imbalance between matter and antimatter in the universe. Because of torsion, matter would decay into familiar electrons and quarks, and antimatter would decay into "dark matter," a mysterious invisible form of matter that appears to account for a majority of matter in the universe.
Finally, torsion could be the source of "dark energy," a mysterious form of energy that permeates all of space and increases the rate of expansion of the universe. Geometry with torsion naturally produces a "cosmological constant," a sort of added-on outward force which is the simplest way to explain dark energy. Thus, the observed accelerating expansion of the universe may end up being the strongest evidence for torsion.
Torsion therefore provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe. It also appears as a remedy to several major problems of current theory of gravity and cosmology. Physicists still need to combine the Einstein-Cartan-Sciama-Kibble theory fully with quantum mechanics into a quantum theory of gravity. While resolving some major questions, it raises new ones of its own. For example, what do we know about the parent universe and the black hole inside which our own universe resides? How many layers of parent universes would we have? How can we test that our universe lives in a black hole?
The last question can potentially be investigated: since all stars and thus black holes rotate, our universe would have inherited the parent black hole’s axis of rotation as a "preferred direction." There is some recently reported evidence from surveys of over 15,000 galaxies that in one hemisphere of the universe more spiral galaxies are "left-handed", or rotating clockwise, while in the other hemisphere more are "right-handed", or rotating counterclockwise. In any case, I believe that including torsion in geometry of spacetime is a right step towards a successful theory of cosmology.
Excerpt from wired.com
In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.
But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.
At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.
But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.
M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.
“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.
That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. 
NASA Ames/SETI Institute/JPL-Caltech
NASA Ames/SETI Institute/JPL-CaltechTo be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.
And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.
But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.
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