Tag: new (page 77 of 147)

Do We Plan Our Lives Before We Are Born?

Nikkie Gray, Collective-EvolutionThe theory that we plan our lives was something I had never heard of before 2011. Up until that point, I could not have even imagined such a thing. Even after hearing about it 3 years ago, it took me quite a long time to let this concept into my paradigm. How I stumbled upon it wasn’t even through my avid research of the afterlife and reincarnation. It came to me through a vision I had. Before the vision, I believed in reincarnation. The idea of it ha [...]

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So what is a supermassive black hole anyway?


Artist's rendering of a black hole recently discovered in the ultracompact dwarf galaxy M60-UCD1.

csmonitor.com

The discovery of a supermassive black hole inside a tiny dwarf galaxy has shed new light on the potential number of black holes in the universe.

An international team of researchers has discovered a supermassive black hole in M60-UCD1, a dwarf galaxy some 54-million light years away. M60-UCD1 is about 500 times smaller than our own galaxy, the Milky Way, and 1,000 times less massive. The researchers published their findings Wednesday in Nature.

Scientists have previously identified numerous supermassive black holes throughout the universe – including one at the center of the Milky Way. But this is the first time that any of these largest types of black holes have been found in such a small galaxy, says study lead author Anil Seth, an assistant professor of physics and astronomy University of Utah in Salt Lake City. 

The revelation that a supermassive black hole can exist within an ultracompact dwarf galaxy could mean that there might be twice as many of these largest black holes than astronomers previously thought.

Black holes come in several different varieties, all of which are characterized by a dense concentration of mass compressed into a tiny space and a gravitational force so powerful it keeps light from escaping.

The smallest kind, called a primordial black hole, is the size of a single atom, but it contains the mass of a large mountain. The most widely understood black holes are known as stellar black holes and can contain 20 times the mass of the sun within a ball of space with a diameter of about 10 miles. Supermassive black holes can be as vast as the entire solar system and contain as much mass as found in 1 million suns combined.

Primordial black holes are believed to have formed during the early evolution of the universe, shortly after the Big Bang. Stellar black holes are thought to be the result of the collapse of a massive star. The formation of supermassive black holes has so far remained something of a mystery.
“We know supermassive black holes exist in the center of most big galaxies … but we actually don’t know how they’re formed,” says Dr. Seth. “We just know they formed a long time ago.”

Black holes are difficult to study because their tendency to pull light inside their centers renders them effectively invisible. 

Telescopes can observe contextual clues that suggest the presence of a black hole, such as stars orbiting around an apparent void.
“We can actually see stars moving around the center of the supermassive black hole of our galaxy,” Seth says. “It is much more difficult to study smaller galaxies.”

This particular dwarf galaxy happens to have so many stars – and a black hole that is so large – that telltale signs of the black hole were detected by two telescopes, the optical/infrared Gemini North telescope atop Hawaii’s Mauna Kea and the Hubble Space Telescope.

Typically, the size of a black hole is directly proportional to the size of the galaxy. Seth suspects that M60-UCD1 is actually the remains of a much larger galaxy.

“We think that this thing is a galaxy where the outer part of the galaxy has been stripped away by an interaction with another bigger galaxy and that the core has been left behind,” Seth explains.
In general, however, current technology has not yet reached a point that enables astronomers to definitively identify the presence of black holes in smaller galaxies.

By studying this and other black holes, scientists hope to unravel some of the mysteries of the origins of the universe.

“It turns out that black holes actually play a pretty big role in how galaxies form,” Seth says. “To understand our origin story we need to understand the formation of galaxies. And black holes, even though they are just a tiny fraction of all the mass in the galaxy, can play a really important role in their evolution."

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Space station detector reports more hints of dark matter—or not



New reports of further evidence for dark matter have been greatly exaggerated. Yesterday, researchers working with the Alpha Magnetic Spectrometer (AMS), a $2 billion cosmic ray detector attached to the International Space Station, reported their latest data on a supposed excess of high-energy positrons from space. They contended—at least in a press release—that the new results could offer new hints that they’ve detected particles of dark matter, the mysterious stuff whose gravity binds the galaxies. But several cosmic ray physicists say that the AMS data are still perfectly consistent with much more mundane explanations of the excess. And they doubt AMS alone will resolve the issue.
The leader of the AMS team, Nobel laureate Samuel Ting of the Massachusetts Institute of Technology in Cambridge, takes care to say that the new results do not prove that AMS has detected dark matter. But he also says the data lend more support to that interpretation than to some others. "The key statement is that we have not found a contradiction with the dark matter explanation," he says.
The controversy centers on AMS's measurement of a key ratio, the number of antimatter positrons to the sum of positrons and electrons. In April 2013, AMS confirmed early reports that as the energy of the particles increased above about 8 gigaelectron Volts (GeV), that ratio, or "positron fraction," increased, even as the individual fluxes of electrons and positrons were falling. That increase in the relative abundance of positrons could signal the presence of dark matter particles. According to many theories, if those particles collide, they would annihilate each other to produce electron-positron pairs. That would alter the balance of electrons and positrons among cosmic rays, as the usual source such as the cloudlike remnants of supernova explosions produce far more electrons than positrons.
However, that interpretation was hardly certain. Even before AMS released its measurement of the ratio, astrophysicists had argued that the excess positrons could potentially emanate from an undetected nearby pulsar. In November 2013, Eli Waxman, a theoretical astrophysicist at the Weizmann Institute of Science in Rehovot, Israel, and colleagues went even further. They argued that the excess positrons could come simply from the interactions of "primary" cosmic rays from supernova remnants with the interstellar medium. If so, then the positrons were just "secondary" rays and nothing to write home about.
However, AMS team researchers see two new features that are consistent with the dark matter interpretation, they reported online yesterday in Physical Review Letters. First, the AMS team now sees that after rising with energy, the positron fraction seems to level off and may begin to fall at an energy of 275 GeV, as would be expected if the excess were produced by colliding dark matter particles, as the original particles' mass would put an upper limit on the energy of the positron they spawned. AMS researchers say the leveling off would be consistent with a dark matter particle with a mass of 1 teraelectron volt (TeV). (Thanks to Albert Einstein’s famous equivalence of mass and energy, the two can be measured in the same units.)
Second, the AMS team measured the spectra of electrons and positrons individually. They found that the spectra have different shapes as energy increases. "It's really surprising that the electrons and positrons are so different," Ting says. And, he argues, the difference suggests that the positrons cannot be secondary cosmic rays produced by primary cosmic ray electrons, as such production should lead to similar spectra.
But some cosmic ray physicists aren't convinced. For example, in AMS's graph of the electron fraction, the error bars at the highest energies are large because the high-energy particles are so rare. And those uncertainties make it unclear whether the positron fraction really starts to drop, says Stéphane Coutu, a cosmic ray physicist at Pennsylvania State University, University Park. And even if the positron fraction does fall at energies higher than AMS reported, that wouldn't prove the positrons come from dark matter annihilations, Coutu says. Such a "cutoff" could easily arise in positrons from a pulsar, he says, if the spatial region in which the pulsar accelerates particles is of limited size. All told, the new results are "probably consistent with anything," Coutu says.
Similarly, Waxman questions Ting's claim that the new data suggest the positrons aren't simply secondary cosmic rays. If that were the case, then the electrons and positrons would be coming from different places and there would be no reason to expect their spectra to be similar, Waxman says. Moreover, he notes, AMS's measurement of the positron fraction seems to level out just at the limit that he and colleagues predicted would be the maximum achievable through secondary cosmic rays. So, in fact, the new data support the interpretation that the positrons are simply secondary cosmic rays, he says. "To me this is a very strong indication that we are seeing cosmic ray interactions.”
Will the argument ever end? AMS is scheduled to take data for 10 more years, which should enable scientists to whittle down the uncertainties and extend their reach toward higher energies, Ting says. "I think we should be able to reach 1 TeV with good statistics," he says, and that should be enough to eventually settle the dispute. But Gregory Tarlé, an astrophysicist at the University of Michigan, Ann Arbor, says, "I don't think that's a legitimate claim." Higher energy cosmic rays arrive at such a low rate that even quadrupling the data set would leave large statistical uncertainties, he says. So, Tarlé suspects, years from now the AMS results will likely look about as ambiguous they do now.

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Galactic Mashup ~ Only 5 Billion Years Until The Milky Way Collides with Andromeda ~ Video

washingtonpost.comScientists already knew that big galaxies like to chow down on smaller ones -- which is just a cute way of saying that when they collide, the larger galaxy gains the mass of the smaller one. According to a new study published ...

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No sedative necessary: Scientists discover new ‘sleep node’ in the brain



No sedative necessary: Scientists discover new 'sleep node' in the brain
Using designer genes, researchers at UB and Harvard were able to 'turn on' specific neurons in the brainstem that result in deep sleep.


medicalxpress.com

(Medical Xpress)—A sleep-promoting circuit located deep in the primitive brainstem has revealed how we fall into deep sleep. Discovered by researchers at Harvard School of Medicine and the University at Buffalo School of Medicine and Biomedical Sciences, this is only the second "sleep node" identified in the mammalian brain whose activity appears to be both necessary and sufficient to produce deep sleep.

Published online in August in Nature Neuroscience, the study demonstrates that fully half of all of the brain's sleep-promoting activity originates from the parafacial zone (PZ) in the brainstem. The brainstem is a primordial part of the brain that regulates basic functions necessary for survival, such as breathing, blood pressure, heart rate and body temperature.
"The close association of a sleep center with other regions that are critical for life highlights the evolutionary importance of sleep in the brain," says Caroline E. Bass, assistant professor of Pharmacology and Toxicology in the UB School of Medicine and Biomedical Sciences and a co-author on the paper.
The researchers found that a specific type of neuron in the PZ that makes the neurotransmitter gamma-aminobutyric acid (GABA) is responsible for deep sleep. They used a set of innovative tools to precisely control these neurons remotely, in essence giving them the ability to turn the neurons on and off at will.
"These new molecular approaches allow unprecedented control over brain function at the cellular level," says Christelle Ancelet, postdoctoral fellow at Harvard School of Medicine. "Before these tools were developed, we often used 'electrical stimulation' to activate a region, but the problem is that doing so stimulates everything the electrode touches and even surrounding areas it didn't. It was a sledgehammer approach, when what we needed was a scalpel."
"To get the precision required for these experiments, we introduced a virus into the PZ that expressed a 'designer' receptor on GABA neurons only but didn't otherwise alter brain function," explains Patrick Fuller, assistant professor at Harvard and senior author on the paper. "When we turned on the GABA neurons in the PZ, the animals quickly fell into a deep sleep without the use of sedatives or sleep aids."
How these neurons interact in the brain with other sleep and wake-promoting brain regions still need to be studied, the researchers say, but eventually these findings may translate into new medications for treating sleep disorders, including insomnia, and the development of better and safer anesthetics.
"We are at a truly transformative point in neuroscience," says Bass, "where the use of designer genes gives us unprecedented ability to control the brain. We can now answer fundamental questions of brain function, which have traditionally been beyond our reach, including the 'why' of sleep, one of the more enduring mysteries in the neurosciences."

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Is the long hidden secret of the great pyramid beginning to emerge through clever investigation?

Has a construction ramp been hidden inside the Great Pyramid for 4500 years? If we compliment Jean Pierre Houdin's theory ( video below) of an internal ramp hidden within the great pyramid with the most intriguing new theory of pyramid construction inv...

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The Meaning of Peace in the Bhagavad Gita

V. Susan Ferguson, ContributorThe superb Sanskrit text, The Bhagavad Gita, is an amazing guide and in my view the ultimate ‘user’s manual’ for the human adventure. This ancient text is a dialogue between two mighty warrior heroes: Krishna and Arjuna. Krishna represents the God within us all, who is always waiting patiently to guide us – if we can listen. Arjuna is the greatest warrior of the time and Krishna is his charioteer, his guide in the battle of life. He wil [...]

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The Enlightenment Test

Enlightenment. The moment we consciously connect to eternal truth. It’s when we see through the veil of this illusionary world, rising above ego, time, materialism, and our own emotions to see the bigger picture—that we are all one. It’s what all gurus, spiritualists, yogis, Buddhists, monks, meditators, shamans, artists, writers, and religious leaders strive for. It’s the state Neo reached at the end of The Matrix, the level Dorothy attained so she could surpa [...]

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