Tag: evidence (page 7 of 29)

Study says the universe may be a hologram






Holograms are two-dimensional pictures that appear to the human eye as three-dimensional objects. Some scientists believe that our universe may behave similarly, existing as a sort of all-encompassing hologram.
As explained by Nature World News, “a mathematical description of the Universe actually requires one fewer dimension than it seems” according to the “holographic principle,” which would indicate that what appears to be a 3-D universe may actually “just be the image of 2-D processes on a huge cosmic horizon.”
Prior to this study, scientists looked into this holographic principle by applying their calculations to a universe presenting Anti de Sitter space. Anti de Sitter is the term used to describe space as having a hyperbolic shape, much like a saddle. This hyperbolic space shape behaves, mathematically, as special relativity would predict.
Special relativity is a theory put forth by Albert Einstein to describe the relationship between space and time, and is especially useful when studying very small particles moving at extreme speeds over cosmic distances. The concept of Anti de Sitter space assumes that spacetime itself is hyperbolic in its natural state, in the absence of matter or energy.
A team at the Vienne University of Technology looked at the holographic principle not in the usual Anti de Sitter space framework, but instead applied the principle to flat spacetime, as represents our physical universe.“Our Universe, in contrast, is quite flat – and on astronomic distances, it has positive curvature,” team member Daniel Grumiller said in a statement.
The team created several gravitational theories that apply to flat space to see if calculations regarding quantum gravity would indicate a holographic description as has occurred in former calculations with theories applied to Anti de Sitter space.
“If quantum gravity in a flat space allows for a holographic description by a standard quantum theory, then there must be physical quantities, which can be calculated in both theories – and the results must agree,” Grumiller said.
The team found that the amount of quantum entanglement required for gravitational theory models expressed the same value in flat quantum gravity as in a low dimensional field theory, showing that the theory of a holographic universe can be successfully applied to the reality of the relatively flat field of spacetime evident in our universe.
“This calculation affirms our assumption that the holographic principle can also be realized in flat spaces. It is evidence for the validity of this correspondence in our universe” team member Max Riegler said.
The results were published in the journal Physical Review Letters.


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Cosmic tsunamis can regenerate ‘dead’ galaxies






Excerpt from thespacereporter.com



Astronomers have recently discovered that giant cosmic shockwaves emanating from colliding galaxy clusters are capable of jumpstarting new star generation.

According to a Nature World News report, galaxies are often clustered into groups containing “red and dead” galaxies that stopped forming new stars long ago. Scientists now believe that these “dead” galaxies can be brought back to “life” by colossal cosmic tsunamis.

To uncover this phenomenon, an international team of researchers observed how galaxy clusters can absorb smaller clusters much as a growing city absorbs its suburbs. When galaxy clusters collide during this absorption process, a huge shockwave of energy is created. This shockwave can re-energize the star formation process, causing dormant galaxies to begin producing new stars again.

Scientists from the University of Lisbon and Leiden Observatory came to this conclusion after studying the merging galaxy cluster officially known as CIZA J2242.8+5301 and affectionately known as the “Sausage.” The Sausage cluster, located 2.3 billion light-years away, showed evidence of its dormant galaxies coming to life with a new round of star formation.

“We assumed that the galaxies would be on the sidelines for this act, but it turns out they have a leading role. The comatose galaxies in the Sausage cluster are coming back to life, with stars forming at a tremendous rate. When we first saw this in the data, we simply couldn’t believe what it was telling us,” Andra Stroe of Liden Observatory said in a statement.The researchers are observing an event that actually unfolded one billion years ago, when the 6-million-mph shockwave spread out from the collision of the clusters. The team believes that the new star formation was instigated by the shockwave’s affect on galactic gas.

“Much like a teaspoon stirring a mug of coffee, the shocks lead to turbulence in the galactic gas. These then trigger an avalanche-like collapse, which eventually leads to the formation of very dense, cold gas clouds, which are vital for the formation of new stars,” Stroe said.

Despite the vigorous production of new stars in this instance, the team believes that, after the initial effects of the tsunami take place, the galaxies fall to an even deeper state of dormancy than before.

David Sobral of the University of Lisbon explains that “star formation at this rate leads to a lot of massive, short-lived stars coming into being, which explode as supernovae a few million years later. The explosions drive huge amounts of gas out of the galaxies and with most of the rest consumed in star formation, the galaxies soon run out of fuel. If you wait long enough, the cluster mergers make the galaxies even more red and dead – they slip back into a coma and have little prospect of a second resurrection.”

The study was published in the journal Monthly Notices of the Royal Astronomical Society.

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Tombs Filled with Dozens of Mummies Discovered in Peru

A burial of a young woman found in the middle of a tomb. Analysis of her skeletal remains reveal that she suffered dental problems, including tooth loss. At one point in her life she suffered an internal hemorrhage in the meninges of her cranium. ...

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NASA Chief Scientist Ellen Stofan Predicts We’ll Find Signs Of Alien Life Within 10 Years

Excerpt from huffingtonpost.comNASA's top scientist predicts that we'll find signs of alien life by 2025, with even stronger evidence for extraterrestrials in the years that follow. "I think we're going to have strong indications of life beyond Ea...

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For the first time, scientists find complex organic molecules in an infant star system



Artist impression of the protoplanetary disk surrounding the young star MWC 480. ALMA has detected the complex organic molecule methyl cyanide in the outer reaches of the disk in the region where comets are believed to form. This is another indication that complex organic chemistry, and potentially the conditions necessary for life, is universal. (B. Saxton/NRAO/AUI/NSF)



Excerpt from washingtonpost.com

We're not special. Or our complex organic molecules aren't, anyway. And that's good news in the hunt for extraterrestrial life.

In a new study published Wednesday in Nature, astronomers found the first signs of the complex, carbon-based molecules that make life possible on Earth in a protoplanetary disk; the region where cosmic building blocks gather to create planets in a brand-new star system. The cyanides found there are essential to life as we know it: without them, there would be no proteins.

"We know when our own solar system was very young, it was rich in water and complex organics. We know that from observing comets," explained study author Karin Öberg, an assistant professor of astronomy at Harvard. Comets have kept the molecules of our solar system's early days locked up tight ever since, which is why scientists are so eager to study them for clues about Earth's formation. These comets show us that certain organic molecules were common in our solar system's pre-planetary days.

But this is the first time we've seen evidence of such molecules ready to seed another star system with planets that could support life.
"We're finding that we're not that special," Öberg said. "Other young solar systems in the making are also rich in the same volatiles, and in similar proportions."

And in this case, she said, being not-special is a great thing: If other solar systems formed just the way ours did, we can hope that they formed some kind of life, too.

Öberg and her colleagues found the molecules using the Atacama Large Millimeter/submillimeter Array (ALMA), a radio telescope with some pretty sweet resolution. They spotted the complex organics as much as 15 billion kilometers from the star itself, which they believe is right smack dab in the middle of the system's comet-forming region. That means the organics could get locked away in comets, just as the ones in our solar system were, and go out to seed future planets with them (as some believe was the case with Earth).

"It was kind of a chance discovery, because we weren't targeting this specific molecule," Öberg said. So she and her team need to go back and look more systematically. She also hopes they'll be able to find more systems to look at. The star they've observed -- MWC 480, located some 455 light-years away in the Taurus star-forming region -- is twice the mass of the sun, so they also hope to find some that are more similar to our host star.

 "We of course want to know whether this is a really common thing or if we just lucked out on this one," Öberg said.

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Study: 70% of People on Antidepressants Don’t Have Depression

Mike Barrett, Natural SocietyIf sales for antidepressants such as Zoloft, Lexapro, or Prozac tell us anything, it’s that depression is sweeping the nation. But a new study questions the validity of most of these sales. The study has found that the majority of individuals on antidepressants – a whopping 69% – do not even meet the criteria for clinical depression. These individuals are likely just experiencing normal sadness and hardships that most of u [...]

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Citizen Scientists Find Green Blobs in Hubble Galaxy Shots





Excerpt from wired.com

In 2007, A Dutch schoolteacher named Hanny var Arkel discovered a weird green glob of gas in space. Sifting through pictures of galaxies online, as part of the citizen science project Galaxy Zoo, she saw a cloud, seemingly glowing, sitting next to a galaxy. Intrigued, astronomers set out to find more of these objects, dubbed Hanny’s Voorwerp (“Hanny’s object” in Dutch). Now, again with the help of citizen scientists, they’ve found 19 more of them, using the Hubble space telescope to snap the eight haunting pictures in the gallery above.



Since var Arkel found the first of these objects, hundreds more volunteers have swarmed to help identify parts of the universe in the Galaxy Zoo gallery. To find this new set, a couple hundred volunteers went through nearly 16,000 pictures online (seven people went through all of them), clicking yes/no/maybe as to whether they saw a weird green blob. Astronomers followed up on the galaxies they identified using ground-based telescopes, and confirmed 19 new galaxies surrounded by green gas.



What causes these wispy tendrils of gas to glow? Lurking at the center of each of these galaxies is a supermassive black hole, millions to billions times as massive as the sun, with gravity so strong that even light can’t escape them. As nearby gas and dust swirls into the black hole, like water circling a drain, that material heats up, producing lots of radiation—including powerful ultraviolet. Beaming out from the galaxy, that ultraviolet radiation strikes nearby clouds of gas, left over from past collisions between galaxies. And it makes the clouds glow an eerie green. “A lot of these bizarre forms we’re seeing in the images arise because these galaxies either interacted with a companion or show evidence they merged with a smaller galaxy,” says William Keel, an astronomer at the University of Alabama, Tuscaloosa.



The eight in this gallery, captured with Hubble, are especially weird. That’s because the quasar, the black-hole engine that’s supposed to be churning out the ultraviolet radiation, is dim—too dim, in fact, to be illuminating the green gas. Apparently, the once-bright quasar has faded. But because that UV light takes hundreds of thousands of years to travel, it can continue to illuminate the gas long after its light source has died away.  


Hubble finds phantom objects close to dead quasars

That glowing gas can tell astronomers a lot about the quasar that brought it to light. “What I’m so excited about is the fact that we can use them to do archaeology,” says Gabriela Canalizo, an astronomer at the University of California, Riverside, who wasn’t part of the new research. Because the streaks of gas are so vast, stretching up to tens of thousands of light years, the way they glow reveals the history of the radiation coming from the quasar. As the quasar fades, so will the gas’s glow, with the regions of gas closer to the quasar dimming first. By analyzing how the glow dwindles with distance from the quasar, astronomers can determine how fast the quasar is fading. “This was something we’ve never been able to do,” Canalizo says.

Measuring how fast the quasar fades allows astronomers to figure out exactly what’s causing it to turn off in the first place. “What makes them dim is running out of material to eat,” Canalizo says. That could happen if the quasar is generating enough radiation to blow away all the gas and dust surrounding the black hole—the same gas and dust that feeds it. Without a steady diet, the quasar is powerless to produce radiation. Only if more gas happens to make its way toward the black hole can the quasar turn on again. The glowing gas can provide details of this process, and if other mechanisms are at play.

With more powerful telescopes, astronomers will likely find many more. Hanny’s Verwoort, it turns out, may not be that weird after all.

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The Story of Human Evolution Now Challenged



Story of Human Evolution Challenged


Excerpt from newhistorian.com

The history of the evolution of early humans has been challenged.
Until now, one of the most dominant theories about our evolution claimed that our genus, Homo, had evolved from smaller early humans becoming taller, heavier and longer-legged. This process eventually resulted in Homo erectus, which was able to migrate out of Africa and colonise Eurasia.

Whilst we know that small-bodied H. erectus, averaging less than five feet tall and weighing under 50 kilograms, were living in southern Europe by 1.77 million years ago, the origin of the larger body size associated with modern humans has been elusive.

The paucity of knowledge about the origins of larger members of the Homo genus is primarily a result of a lack of evidence. Previous estimates of body size had been based on well-preserved specimens which were easy to assign a species to. Since these samples are rare and disparate in terms of both space and time, little is known about geographical and chronological variation in the body sizes of the early Homo.

A joint study between the Universities of Cambridge and Tübingen has shown that increases in body size occurred thousands of years after H. erectus left Africa; this growth in Homo body sizes primarily took place in the Koobi Fora region in modern Kenya.

“The evolution of larger bodies and longer legs can thus no longer be assumed to be the main driving factor behind the earliest excursions of our genus to Eurasia,” said Manuel Will, co-author of the study which has been published in the Journal of Human Evolution.

By using tiny fragments of fossil, the team were able to estimate our earliest ancestors’ height and body mass. Their findings, rather surprisingly, indicate a huge diversity in body size; this is particularly surprising as the wide variation we see in humans today was thought to be a relatively recent development.

“If someone asked you ‘are modern humans 6 foot tall and 70kg?’ you’d say ‘well some are, but many people aren’t,’ and what we’re starting to show is that this diversification happened really early in human evolution,” said Dr Jay Stock, co-author of the study.

Stock and Will are the first scientists in 20 years to compare the body size of humans from between 2.5 and 1.5 million years ago. They are also the first to use fragmentary fossils – many as small as toes, none longer than 5cm – to estimate body sizes.

By comparing measurements of fossils from sites in Kenya, Tanzania, South Africa and Georgia, the researchers have revealed substantial regional variation in the size of early humans. Groups who lived in South African caves, for example, were 4.8 feet tall on average. Some of the skeletons found in Kenya’s Koobi Fora region would have stood nearly 6 feet tall, a height comparable to the average height of modern British males.
“Basically every textbook on human evolution gives the perspective that one lineage of humans evolved larger bodies before spreading beyond Africa. But the evidence for this story about our origins and the dispersal out of Africa just no longer really fits,” said Stock.

It appears that Stock and Will have rewritten the history of the development of early humans; diversity has deep roots amongst the Homo genus.

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