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The Zen of Technology & Scientific Discovery! (& Robots)
All modern humans originated in northern Botswana, study says
There, south of the Greater Zambezi River Basin, which includes northern Botswana and parts of Namibia and Zimbabwe, the ancestors of Homo sapiens began 200,000 years ago, the researchers said.
Their new study, published Monday in the journal Nature, suggests that the ancestors of modern humans thrived for 70,000 years in this region before climate change led them to migrate out of Africa and eventually span the globe.
Previously, some fossil evidence has suggested that modern humans originated in eastern Africa. DNA evidence has pointed to southern Africa, where Botswana is located.
"It has been clear for some time that anatomically modern humans appeared in Africa roughly 200,000 years ago. What has been long debated is the exact location of this emergence and subsequent dispersal of our earliest ancestors," said Vanessa Hayes, lead study author at the Garvan Institute of Medical Research and the University of Sydney. "We've been able to pinpoint what we believe is our human homeland."
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They worked with local communities in Namibia and South Africa to collect blood samples.
"Mitochondrial DNA acts like a time capsule of our ancestral mothers, accumulating changes slowly over generations," Hayes said. "Comparing the complete DNA code, or mitogenome, from different individuals provides information on how closely they are related."
This provided a catalog of more than 1,000 mitogenomes including the L0 lineage, the earliest known modern human populations. The samples also helped the researchers to find rare and new sub-branches of this lineage.
...
"We observed significant genetic divergence in the modern humans' earliest maternal sub-lineages that indicates our ancestors migrated out of the homeland between 130,000 and 110,000 years ago," Hayes said. "The first migrants ventured northeast, followed by a second wave of migrants who traveled southwest. A third population remained in the homeland until today. In contrast to the northeasterly migrants, the southwesterly explorers appear to flourish, experiencing steady population growth."
...
"Our simulations suggest that the slow wobble of Earth's axis changes summer solar radiation in the Southern Hemisphere, leading to periodic shifts in rainfall across southern Africa," said Axel Timmermann, study co-author and director of the IBS Center for Climate Physics at Pusan National University. "These shifts in climate would have opened green, vegetated corridors, first 130,000 years ago to the northeast, and then around 110,000 years ago to the southwest, allowing our earliest ancestors to migrate away from the homeland for the first time."
Humidity levels increased, causing these green, lush pathways to lead away from where modern humans began. These early migrations would pave the way for modern humans to disperse from Africa and eventually settle around the world.
Oh, when they explain it like this, seems like a piece of cake, a walk in the park.
Something hit the breaks hard in the universe without creation running off the road!
Good thing, or we would not be here to survive that crash!
We May Finally Understand the Moments Before the Big Bang
Physicists may have solved a decades-long mystery about how our universe came to be.
There's a hole in the story of how our universe came to be. First, the universe inflated rapidly, like a balloon. Then, everything went boom.
But how those two periods are connected has eluded physicists. Now, a new study suggests a way to link the two epochs.
In the first period, the universe grew from an almost infinitely small point to nearly an octillion (that's a 1 followed by 27 zeros) times that in size in less than a trillionth of a second. This inflation period was followed by a more gradual, but violent, period of expansion we know as the Big Bang. During the Big Bang, an incredibly hot fireball of fundamental particles — such as protons, neutrons and electrons — expanded and cooled to form the atoms, stars and galaxies we see today.
The Big Bang theory, which describes cosmic inflation, remains the most widely supported explanation of how our universe began, yet scientists are still perplexed by how these wholly different periods of expansion are connected. To solve this cosmic conundrum, a team of researchers at Kenyon College, the Massachusetts Institute of Technology (MIT) and the Netherlands' Leiden University simulated the critical transition between cosmic inflation and the Big Bang — a period they call "reheating."
"The post-inflation reheating period sets up the conditions for the Big Bang and, in some sense, puts the 'bang' in the Big Bang," David Kaiser, a professor of physics at MIT, said in a statement. "It's this bridge period where all hell breaks loose and matter behaves in anything but a simple way."
When the universe expanded in a flash of a second during cosmic inflation, all the existing matter was spread out, leaving the universe a cold and empty place, devoid of the hot soup of particles needed to ignite the Big Bang. During the reheating period, the energy propelling inflation is believed to decay into particles, said Rachel Nguyen, a doctoral student in physics at the University of Illinois and lead author of the study.
"Once those particles are produced, they bounce around and knock into each other, transferring momentum and energy," Nguyen told Live Science. "And that's what thermalizes and reheats the universe to set the initial conditions for the Big Bang."
What happens to your brain as you sleep? A new video holds the answer: A juicy mix of blood and cerebrospinal fluid slosh through your smushy noggin in a rhythmic pulsating dance.
The movement appears almost tidal in a video released Oct. 31 along with an article in the journal Science. Though researchers knew that brain activity takes on a rhythmic pattern during sleep, this video and study mark the first time anyone has observed a similarly rhythmic flow of cerebrospinal fluid.
"We've known for a while that there are these electrical waves of activity in the neurons," study co-author Laura Lewis, a professor of biomedical engineering at Boston University, said in a statement. "But before now, we didn't realize that there are actually waves in the CSF, too."
Scientists Find a Spot Where No Life Can Survive. That's Bad News for Alien Hunters.
Unearthly greens and yellows color the scorching-hot landscape surrounding the Dallol volcano in northern Ethiopia. This alien-like world is filled with hydrothermal pools that are some of the most extreme environments on the planet — and some of them seem to be completely devoid of life, according to a new study.
Different life-forms on our planet have adapted to survive under some pretty harsh conditions, places that are superhot, superacidic or supersalty, to name a few, said study senior author Purificación López-García, the research director at the French National Centre for Scientific Research.
But can life survive in a single environment that combines all three conditions, such as in the colorful waters of the Dallol hydrothermal region?
To figure out if this extreme environment oversteps the limits for life on our planet, the researchers sampled a number of brines— or pools of water with high concentrations of salt — in the area. Some were extremely hot, salty and acidic, while others were still very hot and salty but weren't too acidic or basic. The scientists analyzed all the genetic material found in the samples to identify any organisms living there.
...
In these most extreme environments, that were really acidic, hot and contained magnesium salts, the researchers found no DNA and thus no trace of a living organism, the study said.
Earth was on the other side of the galaxy when dinosaurs reigned
NASA research scientist Jessie Christiansen ... told her fellow stargazers that before they went extinct, dinosaurs wouldn't have even seen these stars in the sky because they didn't exist until millions of years after the extinction event. And she told them that when dinosaurs such as stegosaurs roamed the Earth, our entire solar neighborhood was on the opposite of the Milky Way galaxy that it is now.
Christiansen wasn't sharing new information, she said. But the fact caught everyone's attention because the movement of our solar system as it orbits the galaxy isn't something most people think about.
"You don't think about the sky changing," Christiansen said. "But the stars come and go, in step with our timescales."
She had been wanting to create an animation of this intriguing idea for a while and the reaction of the stargazers inspired her one night after her children went to bed.
Also, an amazing illustration of how long the dinosaurs were here compared to little (not so) old us!
Well, this will give a headache to anyone ... except maybe a physicist or a Zen person ...
Objective Reality Doesn't Exist, Quantum Experiment Shows
By Alessandro Fedrizzi - Professor of Quantum Physics, Heriot-Watt University
... in a paper recently published in Science Advances, we show that, in the micro-world of atoms and particles that is governed by the strange rules of quantum mechanics, two different observers are entitled to their own facts. In other words, according to our best theory of the building blocks of nature itself, facts can actually be subjective.
Observers are powerful players in the quantum world. According to the theory, particles can be in several places or states at once — this is called a superposition. But oddly, this is only the case when they aren't observed. The second you observe a quantum system, it picks a specific location or state — breaking the superposition. The fact that nature behaves this way has been proven multiple times in the lab — for example, in the famous double slit experiment.
In 1961, physicist Eugene Wigner proposed a provocative thought experiment. He questioned what would happen when applying quantum mechanics to an observer that is themselves being observed. Imagine that a friend of Wigner tosses a quantum coin — which is in a superposition of both heads and tails — inside a closed laboratory. Every time the friend tosses the coin, they observe a definite outcome. We can say that Wigner's friend establishes a fact: the result of the coin toss is definitely head or tail.
Wigner doesn't have access to this fact from the outside, and according to quantum mechanics, must describe the friend and the coin to be in a superposition of all possible outcomes of the experiment. That's because they are "entangled" — spookily connected so that if you manipulate one you also manipulate the other. Wigner can now in principle verify this superposition using a so-called "interference experiment" — a type of quantum measurement that allows you to unravel the superposition of an entire system, confirming that two objects are entangled.
When Wigner and the friend compare notes later on, the friend will insist they saw definite outcomes for each coin toss. Wigner, however, will disagree whenever he observed friend and coin in a superposition.
This presents a conundrum. The reality perceived by the friend cannot be reconciled with the reality on the outside.
...
Scientifically, there has been little progress on this until very recently, when Časlav Brukner at the University of Vienna showed that, under certain assumptions, Wigner's idea can be used to formally prove that measurements in quantum mechanics are subjective to observers. ... Brukner considered two pairs of Wigners and friends, in two separate boxes, conducting measurements on a shared state — inside and outside their respective box. ...
... We have now for the first time performed this test experimentally at Heriot-Watt University in Edinburgh on a small-scale quantum computer made up of three pairs of entangled photons. The first photon pair represents the coins, and the other two are used to perform the coin toss — measuring the polarization of the photons — inside their respective box. Outside the two boxes, two photons remain on each side that can also be measured.
Despite using state-of-the-art quantum technology, it took weeks to collect sufficient data from just six photons to generate enough statistics. But eventually, we succeeded in showing that quantum mechanics might indeed be incompatible with the assumption of objective facts — we violated the inequality.
The theory, however, is based on a few assumptions. These include that the measurement outcomes are not influenced by signals traveling above light speed and that observers are free to choose what measurements to make. That may or may not be the case. ...
... Another important question is whether single photons can be considered to be observers. In Brukner's theory proposal, observers do not need to be conscious, they must merely be able to establish facts in the form of a measurement outcome. An inanimate detector would therefore be a valid observer. And textbook quantum mechanics gives us no reason to believe that a detector, which can be made as small as a few atoms, should not be described as a quantum object just like a photon. ...
... This experiment therefore shows that, at least for local models of quantum mechanics, we need to rethink our notion of objectivity. The facts we experience in our macroscopic world appear to remain safe, but a major question arises over how existing interpretations of quantum mechanics can accommodate subjective facts.
Some physicists see these new developments as bolstering interpretations that allow more than one outcome to occur for an observation, for example the existence of parallel universes in which each outcome happens. Others see it as compelling evidence for intrinsically observer-dependent theories such as Quantum Bayesianism, in which an agent's actions and experiences are central concerns of the theory. But yet others take this as a strong pointer that perhaps quantum mechanics will break down above certain complexity scales.
Clearly these are all deeply philosophical questions about the fundamental nature of reality. Whatever the answer, an interesting future awaits. ...
Chop wood and fetch water, and do not chop wood nor fetch water, chop wood but do not fetch water, do not chop wood yet fetch water ... at once as a super-imposition!
Anyway, no wood, no water, nor separate chopper and fetcher.
Water vapor detected on Jupiter's moon Europa, adding intrigue to potential for life
For the first time, scientists have discovered the presence of water vapor above the surface on Europa, Jupiter's icy moon first visited by one of the Voyager probes 40 years ago.
This adds to the intrigue of other previously discovered factors associated with the potential for life on Europa. The findings were published in the journal Nature Astronomy on Monday.
... "Essential chemical elements and sources of energy, two of [the] three requirements for life, are found all over the solar system. But the third — liquid water — is somewhat hard to find beyond Earth," said Lucas Paganini, study author and NASA planetary scientist. ...
... Research suggesting the possibility of an ocean on Europa was published as early as 1977, after the Voyager mission observed long lines and dark spots instead of a cratered surface similar to other moons. Then the Galileo spacecraft reached Europa in 1996 and revealed for the first time that there was an ocean on another planet. ... As Paganini noted, the necessary ingredients for life as we know it include liquid water, energy sources and chemicals such as carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus. Europa and Saturn's moon Enceladus show some of these key ingredients for life in their oceans, which is why researchers believe they are the best chance for finding life beyond Earth in our own solar system. ...
Europa has been a high priority for scientists because, as an ice-covered moon with a subsurface salty liquid ocean, it has been identified as one of the ideal spots for hosting life.
Secretive energy startup backed by Bill Gates achieves solar breakthrough
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Heliogen, a clean energy company that emerged from stealth mode on Tuesday, said it has discovered a way to use artificial intelligence and a field of mirrors to reflect so much sunlight that it generates extreme heat above 1,000 degrees Celsius.
Essentially, Heliogen created a solar oven — one capable of reaching temperatures that are roughly a quarter of what you'd find on the surface of the sun.
The breakthrough means that, for the first time, concentrated solar energy can be used to create the extreme heat required to make cement, steel, glass and other industrial processes. In other words, carbon-free sunlight can replace fossil fuels in a heavy carbon-emitting corner of the economy that has been untouched by the clean energy revolution.
We are rolling out technology that can beat the price of fossil fuels and also not make the CO2 emissions," Bill Gross, Heliogen's founder and CEO, told CNN Business. "And that's really the holy grail."
Heliogen, which is also backed by billionaire Los Angeles Times owner Patrick Soon-Shiong, believes the patented technology will be able to dramatically reduce greenhouse gas emissions from industry. Cement, for example, accounts for 7% of global CO2 emissions, according to the International Energy Agency.
... For now, Heliogen is squarely focused on solar. One problem with solar is that the sun doesn't always shine, yet industrial companies like cement makers have a constant need for heat. Heliogen said it would solve that issue by relying on storage systems that can hold the solar energy for rainy days.
This technology will only become more sophisticated, so this is a first step ... first touch. Since our experience of touch is already the brain's reaction to electro-chemical signals from the skin and accompanying senses transmitted by nerve endings, even the touch of our loved ones are already mediated and indirect to large extent through our senses, nervous system and brain (which fact does not render the experience less meaningful or "real" by the way) ...
New 'smart skin' may let you reach out and virtually touch -- anyone
Visualize touching your sweetheart's face on the screen of your laptop and seeing a reaction to your touch in real time, even though you are miles apart. Suddenly, you feel a touch on your face.
Or if you're a grandparent, imagine making a hugging motion during an internet video call with your grandchild and watching them squirm in delight. Now imagine feeling that child's sweet kiss on your cheek. ...
For years, science has been scrambling to add tactile sensation to our virtual experiences. Various types of electronic skins have been developed, typically reliant on clunky wired electrodes that provide less than instantaneous response and a lack of two-way feedback. ...
In a paper published Wednesday in the journal Nature, Rogers and his team at Northwestern report a new wireless and battery-free smart skin that could shift the course of this technology. Through a fast, programmable array of miniature vibrating disks embedded in a soft, flexible material, this smart skin can contour to the body and deliver sensory input -- what you'd feel when using it -- that Rogers says is quite natural.
"I would say a gentle touch or kind of a stroke, a type of sensation that you might feel if you rub your finger across your skin," Rogers said.
The applications for such a flexible smart skin are wide: social media, entertainment, virtual reality and video gaming, sensory feedback for amputees, even telemedicine could be given a human touch, the study said. At the office, employees could shake the hand of every businessperson attending a virtual meeting and feel a squeeze in return. ...
Osborn's team previously developed a sensory feedback tool called an "e-dermis" that fits over prosthetic hands and mimics nerve endings, allowing amputees to feel pain. The new smart skin developed by the Northwestern team would add to that technology, allowing amputees "to understand how much force they're using when they grasp an object as well as how hot or cold the object is," Rogers said.
... There are other applications as well. Not only can lovers, grandparents and businessmen reach out and touch people to better communicate, but so could politicians, world figures, and movie and music icons.
Think of your favorite music artist reaching out to touch everyone in the audience during a concert, or even a music video.
If I may quote a line or two from my essay "The world is virtual, this sangha is real" ... the future of Treeleaf ...
With Gassho before a body scanner, sitters will enter the 3-D Holographic Zen Hall from wherever they are. Instantly, a high roofed room, Manjusri Bodhisattva at its center, fills the senses and the 10 directions encircling them. Lifelike images of a hundred others who have sat that day (some hours earlier in distant time zones) occupy projected Zafus all around, and the scent of incense perfumes the air. A young priest walks through the room straightening slippers (all made of photons), guiding newcomers to their places. Biosensors in the sitter’s clothing adjust posture with a touch lightly felt at the small of the back. ...
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THE WORLD IS VIRTUAL, THIS SANGHA IS REAL
By Jundo Cohen
With Gassho before a body scanner, sitters will enter the 3-D Holographic Zen Hall from wherever they are. Instantly, a high roofed room, Manjusri Bodhisattva at its center, fills the senses and the 10 directions encircling them. Lifelike images of a hundred
Your RNA May Have Come from Space, Meteor Study Suggests
A new study suggests that when some ancient meteorites crash-land on Earth, they bring a dash of extraterrestrial sugar with them.
To be clear, this is not table sugar (sadly, scientists still have no insight into whether aliens prefer their coffee black or sweetened). Rather, in the powdered samples of two ancient, carbon-filled meteorites, astronomers have found traces of several sugars that are key to life — including ribose, the sugary base of RNA (ribonucleic acid).
According to lead study author Yoshihiro Furukawa, this is the first time that these bioessential sugars have been detected in meteorites. The find gives fresh fuel to the idea that the essential building blocks of life on Earth were forged in space, before crash-landing on our young planet billions of years ago, Furukawa said.
"Other important building blocks of life have been found in meteorites previously, including amino acids (components of proteins) and nucleobases (components of DNA and RNA), but sugars have been a missing piece," Furukawa, an associate professor at Tohoku University in Japan, said in a statement. https://www.livescience.com/space-su...a-metoers.html
Scientists have finally found traces of the axion, an elusive particle that rarely interacts with normal matter. The axion was first predicted over 40 years ago but has never been seen until now.
Scientists have suggested that dark matter, the invisible matter that permeates our universe, may be made of axions. But rather than finding a dark matter axion deep in outer space, researchers have discovered mathematical signatures of an axion in an exotic material here on Earth.
The newly discovered axion isn't quite a particle as we normally think of it: It acts as a wave of electrons in a supercooled material known as a semimetal. But the discovery could be the first step in addressing one of the major unsolved problems in particle physics.
The axion is a candidate for dark matter, since, just like dark matter, it can't really interact with regular matter. This aloofness also makes the axion, if it exists, extremely difficult to detect. This strange particle could also help solve a long-standing conundrum in physics known as "the strong CP problem." For some reason, the laws of physics seem to act the same on particles and their antimatter partners, even when their spatial coordinates are inverted.This phenomenon is known as charge-parity symmetry, but existing physics theory says there's no reason this symmetry has to exist. The unexpected symmetry can be explained by the existence of a special field; detecting an axion would prove that this field exists, solving this mystery.
A 'no-brainer Nobel Prize': Hungarian scientists may have found a fifth force of nature
Scientists at the Institute for Nuclear Research at the Hungarian Academy of Sciences (Atomki) have posted findings showing what could be an example of that fifth force at work.
The scientists were closely watching how an excited helium atom emitted light as it decayed. The particles split at an unusual angle, 115 degrees, which couldn't be explained by known physics.
The study's lead scientist, Attila Krasznahorkay, told CNN that this was the second time his team had detected a new particle, which they call X17, because they calculated its mass at 17 megaelectronvolts.
"X17 could be a particle, which connects our visible world with the dark matter," he said in an email.
Jonathan Feng, a professor of physics and astronomy at the University of California, Irvine, told CNN he's been following the Hungarian team's work for years, and believes their research is shaping up to be a game changer.
If these results can be replicated, "this would be a no-brainer Nobel Prize," he said.
The findings point toward the Holy Grail of physics
To move their breakthrough idea from 2016 forward, the Hungarians would need to repeat the results again. That's exactly what their 2019 results do.
Feng says there was only a one in a trillion chance that the results were caused by anything other than the X17 particle, and this new fifth force.
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