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An interface system that uses augmented reality technology could help individuals with profound motor impairments operate a humanoid robot to feed themselves and perform routine personal care tasks such as scratching an itch and applying skin lotion. The web-based interface displays a “robot’s eye view” of surroundings to help users interact with the world through the machine.

The system, described March 15 in the journal PLOS ONE, could help make sophisticated robots more useful to people who do not have experience operating complex robotic systems. Study participants interacted with the robot interface using standard assistive computer access technologies – such as eye trackers and head trackers – that they were already using to control their personal computers.

The paper reported on two studies showing how such “robotic body surrogates” – which can perform tasks similar to those of humans – could improve the quality of life for users. The work could provide a foundation for developing faster and more capable assistive robots.

“Our results suggest that people with profound motor deficits can improve their quality of life using robotic body surrogates,” said Phillip Grice, a recent Georgia Institute of Technology Ph.D. graduate who is first author of the paper. “We have taken the first step toward making it possible for someone to purchase an appropriate type of robot, have it in their home and derive real benefit from it.”

Grice and Professor Charlie Kemp from the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University used a PR2 mobile manipulator manufactured by Willow Garage for the two studies. The wheeled robot has 20 degrees of freedom, with two arms and a “head,” giving it the ability to manipulate objects such as water bottles, washcloths, hairbrushes and even an electric shaver.

“Our goal is to give people with limited use of their own bodies access to robotic bodies so they can interact with the world in new ways,” said Kemp.

In their first study, Grice and Kemp made the PR2 available across the internet to a group of 15 participants with severe motor impairments. The participants learned to control the robot remotely, using their own assistive equipment to operate a mouse cursor to perform a personal care task. Eighty percent of the participants were able to manipulate the robot to pick up a water bottle and bring it to the mouth of a mannequin.

“Compared to able-bodied persons, the capabilities of the robot are limited,” Grice said. “But the participants were able to perform tasks effectively and showed improvement on a clinical evaluation that measured their ability to manipulate objects compared to what they would have been able to do without the robot.”

In the second study, the researchers provided the PR2 and interface system to Henry Evans, a California man who has been helping Georgia Tech researchers study and improve assistive robotic systems since 2011. Evans, who has very limited control of his body, tested the robot in his home for seven days and not only completed tasks, but also devised novel uses combining the operation of both robot arms at the same time – using one arm to control a washcloth and the other to use a brush.

“The system was very liberating to me, in that it enabled me to independently manipulate my environment for the first time since my stroke,” said Evans. “With respect to other people, I was thrilled to see Phil get overwhelmingly positive results when he objectively tested the system with 15 other people.”

The researchers were pleased that Evans developed new uses for the robot, combining motion of the two arms in ways they had not expected.

“When we gave Henry free access to the robot for a week, he found new opportunities for using it that we had not anticipated,” said Grice. “This is important because a lot of the assistive technology available today is designed for very specific purposes. What Henry has shown is that this system is powerful in providing assistance and empowering users. The opportunities for this are potentially very broad.”

The interface allowed Evans to care for himself in bed over an extended period of time. “The most helpful aspect of the interface system was that I could operate the robot completely independently, with only small head movements using an extremely intuitive graphical user interface,” Evans said.

The web-based interface shows users what the world looks like from cameras located in the robot’s head. Clickable controls overlaid on the view allow the users to move the robot around in a home or other environment and control the robot’s hands and arms. When users move the robot’s head, for instance, the screen displays the mouse cursor as a pair of eyeballs to show where the robot will look when the user clicks. Clicking on a disc surrounding the robotic hands allows users to select a motion. While driving the robot around a room, lines following the cursor on the interface indicate the direction it will travel.

Building the interface around the actions of a simple single-button mouse allows people with a range of disabilities to use the interface without lengthy training sessions.

“Having an interface that individuals with a wide range of physical impairments can operate means we can provide access to a broad range of people, a form of universal design,” Grice noted. “Because of its capability, this is a very complex system, so the challenge we had to overcome was to make it accessible to individuals who have very limited control of their own bodies.”

While the results of the study demonstrated what the researchers had set out to do, Kemp agrees that improvements can be made. The existing system is slow, and mistakes made by users can create significant setbacks. Still, he said, “People could use this technology today and really benefit from it.”

The cost and size of the PR2 would need to be significantly reduced for the system to be commercially viable, Evans suggested. Kemp says these studies point the way to a new type of assistive technology.

“It seems plausible to me based on this study that robotic body surrogates could provide significant benefits to users,” Kemp added.

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Distinguished Professor Sheldon Stone says the findings are a first, although matter-antimatter asymmetry has been observed before in particles with strange quarks or beauty quarks.

He and members of the College’s High-Energy Physics (HEP) research group have measured, for the first time and with 99.999-percent certainty, a difference in the way D0mesons and anti-D0 mesons transform into more stable byproducts.

Mesons are subatomic particles composed of one quark and one antiquark, bound together by strong interactions.

“There have been many attempts to measure matter-antimatter asymmetry, but, until now, no one has succeeded,” says Stone, who collaborates on the Large Hadron Collider beauty (LHCb) experiment at the CERN laboratory in Geneva, Switzerland. “It’s a milestone in antimatter research.”

The findings may also indicate new physics beyond the Standard Model, which describes how fundamental particles interact with one another. “Till then, we need to await theoretical attempts to explain the observation in less esoteric means,” he adds.

Every particle of matter has a corresponding antiparticle, identical in every way, but with an opposite charge. Precision studies of hydrogen and antihydrogen atoms, for example, reveal similarities to beyond the billionth decimal place.

When matter and antimatter particles come into contact, they annihilate each other in a burst of energy – similar to what happened in the Big Bang, some 14 billion years ago.

“That’s why there is so little naturally occurring antimatter in the Universe around us,” says Stone, a Fellow of the American Physical Society, which has awarded him this year’s W.K.H. Panofsky Prize in Experimental Particle Physics.

The question on Stone’s mind involves the equal-but-opposite nature of matter and antimatter. “If the same amount of matter and antimatter exploded into existence at the birth of the Universe, there should have been nothing left behind but pure energy. Obviously, that didn’t happen,” he says in a whiff of understatement.

Thus, Stone and his LHCb colleagues have been searching for subtle differences in matter and antimatter to understand why matter is so prevalent.

The answer may lie at CERN, where scientists create antimatter by smashing protons together in the Large Hadron Collider (LHC), the world’s biggest, most powerful particular accelerator. The more energy the LHC produces, the more massive are the particles – and antiparticles – formed during collision.

It is in the debris of these collisions that scientists such as Ivan Polyakov, a postdoc in Syracuse’s HEP group, hunt for particle ingredients.

“We don’t see antimatter in our world, so we have to artificially produce it,” he says. “The data from these collisions enables us to map the decay and transformation of unstable particles into more stable byproducts.”

HEP is renowned for its pioneering research into quarks – elementary particles that are the building blocks of matter. There are six types, or flavors, of quarks, but scientists usually talk about them in pairs: up/down, charm/strange and top/bottom. Each pair has a corresponding mass and fractional electronic charge.

In addition to the beauty quark (the “b” in “LHCb”), HEP is interested in the charmed quark. Despite its relatively high mass, a charmed quark lives a fleeting existence before decaying into something more stable.

Recently, HEP studied two versions of the same particle. One version contained a charmed quark and an antimatter version of an up quark, called the anti-up quark. The other version had an anti-charm quark and an up quark.

Using LHC data, they identified both versions of the particle, well into the tens of millions, and counted the number of times each particle decayed into new byproducts.

“The ratio of the two possible outcomes should have been identical for both sets of particles, but we found that the ratios differed by about a tenth of a percent,” Stone says. “This proves that charmed matter and antimatter particles are not totally interchangeable.”

Adds Polyakov, “Particles might look the same on the outside, but they behave differently on the inside. That is the puzzle of antimatter.”

The idea that matter and antimatter behaves differently is not new. Previous studies of particles with strange quarks and bottom quarks have confirmed as such.

What makes this study unique, Stone concludes, is that it is the first time anyone has witnessed particles with charmed quarks being asymmetrical: “It’s one for the history books.”

HEP’s work is supported by the National Science Foundation.

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by Donna Pierce

Jupiter’s Great Red Spot. NASA/JPL-Caltech/SwRI/MSSS/ Gerald Eichstädt /Seán Doran


The Great Red Spot, a storm larger than the Earth and powerful enough to tear apart smaller storms that get drawn into it, is one of the most recognizable features in Jupiter’s atmosphere and the entire solar system. The counterclockwise-moving storm, an anticyclone, boasts wind speeds as high as 300 miles per hour. This prominent feature, observed since 1830, and possibly as far back as the 1660s, has long been a source of great fascination and scientific study.

Much about the Great Red Spot is still unknown, including exactly when and how it formed, what gives it its striking red color and why it has persisted for so much longer than other storms that have been observed in the atmosphere of Jupiter. However, astronomers think that its position in latitude, consistently observed to be 22 degrees south of Jupiter’s equator, is connected to the prominent cloud bands in Jupiter’s atmosphere.

As a planetary astronomer who studies the atmospheres of comets, I’m normally not investigating massive storms. But I still want to know about the features seen in the atmosphere of other bodies in the solar system, including Jupiter. Studying atmospheres of all kinds deepens our understanding of how they form and work.

Unlike Jupiter, the Earth has land masses that cause major storms to lose energy due to friction with a solid surface. Without this feature, Jupiter’s storms are more long-lasting. However, the Great Red Spot is long-lived, even by Jupiter standards. Researchers don’t quite understand why, but we do know that Jupiter’s storms that are located in cloud bands with the same direction of rotation tend to be longer lasting.

The planets of the solar system to size scale. Jupiter is five times further from the Sun than the Earth. CC BY-SA

These colorful alternating bands, called belts (dark bands) and zones (light bands), run parallel to Jupiter’s equator. Researchers aren’t sure what causes the coloration of the bands and zones, but differences in their chemical composition, temperature and transparency of the atmosphere to light have all been suggested as contributing factors. These bands are also counter-rotating, meaning that they move in opposite directions with respect to their neighbors. The boundaries between the bands and zones are marked by strong winds called zonal jets.

The Great Red Spot is confined by an eastward jet to its north and a westward jet to its south, confining the storm to a constant latitude. However, the Great Red Spot has undergone considerable changes in longitude over time, and recent evidence suggests that its rate of westward longitudinal motion is increasing.

Like the Great Red Spot, the bands have undergone little change in latitude over the time during which they have been observed. Researchers don’t entirely understand the banded structure, but we do have evidence suggesting that the light colored zones are regions of rising material, and the dark belts are regions of material sinking into the atmosphere.

On Earth, there is a well-defined boundary between the atmosphere and the surface of the planet, which is largely covered by liquid water. However, there are no known large oceans of water under Jupiter’s clouds. Based on what researchers do know, the atmosphere smoothly transitions to a liquid hydrogen interior within the planet. There may be a solid core to Jupiter, but it is most likely buried very deep under a thick layer of liquid metallic hydrogen, a form of hydrogen that acts as an electrical conductor.

What else do we know about the Great Red Spot that is changing dramatically? Its size, shape and color. An analysis of historical and recently obtained data on the Great Red Spot has shown that it is shrinking and becoming both rounder and taller, and its color has also varied over time. What is driving these changes, and what do they mean for the future of the Great Red Spot? Researchers aren’t sure.

However, NASA’s Juno spacecraft, currently orbiting Jupiter, is gathering more data on the cloud bands and the Great Red Spot. These new data will likely provide insights into many of the features in Jupiter’s atmosphere.








About The Author:

Donna Pierce is Associate Professor of Physics and Astronomy at Mississippi State University.

This article is republished from our content partners at The Conversation under a Creative Commons license. 

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by Shinsuke Shimojo, Daw-An Wu, and Joseph Kirschvink

Do you have a magnetic compass in your head? Lightspring/Shutterstock.com


Do human beings have a magnetic sense? Biologists know other animals do. They think it helps creatures including bees, turtles and birds navigate through the world.

Scientists have tried to investigate whether humans belong on the list of magnetically sensitive organisms. For decades, there’s been a back-and-forth between positive reports and failures to demonstrate the trait in people, with seemingly endless controversy.

The mixed results in people may be due to the fact that virtually all past studies relied on behavioral decisions from the participants. If human beings do possess a magnetic sense, daily experience suggests that it would be very weak or deeply subconscious. Such faint impressions could easily be misinterpreted – or just plain missed – when trying to make decisions.

So our research group – including a geophysical biologist, a cognitive neuroscientist and a neuroengineer – took another approach. What we found arguably provides the first concrete neuroscientific evidence that humans do have a geomagnetic sense.

How does a biological geomagnetic sense work? Life on Earth is exposed to the planet’s ever-present geomagnetic field that varies in intensity and direction across the planetary surface. Nasky/Shutterstock.com

The Earth is surrounded by a magnetic field, generated by the movement of the planet’s liquid core. It’s why a magnetic compass points north. At Earth’s surface, this magnetic field is fairly weak, about 100 times weaker than that of a refrigerator magnet.

Over the past 50 years or so, scientists have shown that hundreds of organisms in nearly all branches of the bacterial, protist and animal kingdoms have the ability to detect and respond to this geomagnetic field. In some animals – such as honey bees – the geomagnetic behavioral responses are as strong as the responses to light, odor or touch. Biologists have identified strong responses in vertebrates ranging from fish, amphibians, reptiles, numerous birds and a diverse variety of mammals including whales, rodents, bats, cows and dogs – the last of which can be trained to find a hidden bar magnet. In all of these cases, the animals are using the geomagnetic field as components of their homing and navigation abilities, along with other cues like sight, smell and hearing.

Skeptics dismissed early reports of these responses, largely because there didn’t seem to be a biophysical mechanism that could translate the Earth’s weak geomagnetic field into strong neural signals. This view was dramatically changed by the discovery that living cells have the ability to build nanocrystals of the ferromagnetic mineral magnetite – basically, tiny iron magnets. Biogenic crystals of magnetite were first seen in the teeth of one group of mollusks, later in bacteria, and then in a variety of other organisms ranging from protists and animals such as insects, fish and mammals, including within tissues of the human brain.

Chains of magnetosomes from a sockeye salmon. Mann, Sparks, Walker & Kirschvink, 1988, CC BY-ND

Nevertheless, scientists haven’t considered humans to be magnetically sensitive organisms.

Manipulating the magnetic field Schematic drawing of the human magnetoreception test chamber at Caltech. Modified from ‘Center of attraction’ by C. Bickel (Hand, 2016).

In our new study, we asked 34 participants simply to sit in our testing chamber while we directly recorded electrical activity in their brains with electroencephalography (EEG). Our modified Faraday cage included a set of 3-axis coils that let us create controlled magnetic fields of high uniformity via electric current we ran through its wires. Since we live in mid-latitudes of the Northern Hemisphere, the environmental magnetic field in our lab dips downwards to the north at about 60 degrees from horizontal.

In normal life, when someone rotates their head – say, nodding up and down or turning the head from left to right – the direction of the geomagnetic field (which remains constant in space) will shift relative to their skull. This is no surprise to the subject’s brain, as it directed the muscles to move the head in the appropriate fashion in the first place.

Study participants sat in the experimental chamber facing north, while the downwards-pointing field rotated clockwise (blue arrow) from northwest to northeast or counterclockwise (red arrow) from northeast to northwest. Magnetic Field Laboratory, Caltech, CC BY-ND

In our experimental chamber, we can move the magnetic field silently relative to the brain, but without the brain having initiated any signal to move the head. This is comparable to situations when your head or trunk is passively rotated by somebody else, or when you’re a passenger in a vehicle which rotates. In those cases, though, your body will still register vestibular signals about its position in space, along with the magnetic field changes – in contrast, our experimental stimulation was only a magnetic field shift. When we shifted the magnetic field in the chamber, our participants did not experience any obvious feelings.

The EEG data, on the other hand, revealed that certain magnetic field rotations could trigger strong and reproducible brain responses. One EEG pattern known from existing research, called alpha-ERD (event-related desynchronization), typically shows up when a person suddenly detects and processes a sensory stimulus. The brains were “concerned” with the unexpected change in the magnetic field direction, and this triggered the alpha-wave reduction. That we saw such alpha-ERD patterns in response to simple magnetic rotations is powerful evidence for human magnetoreception.

Alpha wave amplitude - YouTube
Video shows the dramatic, widespread drop in alpha wave amplitude (deep blue color on leftmost head) following counterclockwise rotations. No drop is observed after clockwise rotation or in the fixed condition. Connie Wang, Caltech

Our participants’ brains only responded when the vertical component of the field was pointing downwards at about 60 degrees (while horizontally rotating), as it does naturally here in Pasadena, California. They did not respond to unnatural directions of the magnetic field – such as when it pointed upwards. We suggest the response is tuned to natural stimuli, reflecting a biological mechanism that has been shaped by natural selection.

Other researchers have shown that animals’ brains filter magnetic signals, only responding to those that are environmentally relevant. It makes sense to reject any magnetic signal that is too far away from the natural values because it most likely is from a magnetic anomaly - a lighting strike, or lodestone deposit in the ground, for example. One early report on birds showed that robins stop using the geomagnetic field if the strength is more than about 25 percent different from what they were used to. It’s possible this tendency might be why previous researchers had trouble identifying this magnetic sense – if they cranked up the strength of the magnetic field to “help” subjects detect it, they might have instead ensured that subjects’ brains ignored it.

Moreover, our series of experiments show that the receptor mechanism – the biological magnetometer in human beings – is not electrical induction, and can tell north from south. This latter feature rules out completely the so-called “quantum compass” or “cryptochrome” mechanism which is popular these days in the animal literature on magnetoreception. Our results are consistent only with functional magnetoreceptor cells based on the biological magnetite hypothesis. Note that a magnetite-based system can also explain all of the behavioral effects in birds that promoted the rise of the quantum compass hypothesis.

Brains register magnetic shifts, subconsciously

Our participants were all unaware of the magnetic field shifts and their brain responses. They felt that nothing had happened during the whole experiment – they’d just sat alone in dark silence for an hour. Underneath, though, their brains revealed a wide range of differences. Some brains showed almost no reaction, while other brains had alpha waves that shrank to half their normal size after a magnetic field shift.

It remains to be seen what these hidden reactions might mean for human behavioral capabilities. Do the weak and strong brain responses reflect some kind of individual differences in navigational ability? Can those with weaker brain responses benefit from some kind of training? Can those with strong brain responses be trained to actually feel the magnetic field?

A human response to Earth-strength magnetic fields might seem surprising. But given the evidence for magnetic sensation in our animal ancestors, it might be more surprising if humans had completely lost every last piece of the system. Thus far, we’ve found evidence that people have working magnetic sensors sending signals to the brain – a previously unknown sensory ability in the subconscious human mind. The full extent of our magnetic inheritance remains to be discovered.








About The Authors:

Shinsuke Shimojo is a Gertrude Baltimore Professor of Experimental Psychology at the California Institute of Technology; Daw-An Wu is also with the California Institute of Technology, and Joseph Kirschvink is a Nico and Marilyn Van Wingen Professor of Geobiology at the California Institute of Technology.

This article is republished from our content partners at The Conversation under a Creative Commons license. 

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by Allyson Brady

Scientists conduct research in Hawai'i Volcanoes National Park to practice for Mars landings. Shutterstock


Imagine astronauts on Mars, tasked with picking rock samples that will be used by scientists to search for signs of life. But they can only transport a limited number back to Earth. What should they look for? Are some types of rocks better than others? They could try to ask for advice from the team of geologists and biologists back on Earth, but due to the distance between Earth and Mars it could take roughly 40 minutes before they would receive a response.

This isn’t practical when time outside of the spacecraft can only last for a few hours.

When humans are sent to Mars, it is important that these explorers have the support needed to help them do the best science possible.

How do we explore and do good science given necessary operational constraints? This is an important question that the National Aeronautics and Space Administration (NASA) and other space agencies, including the Canadian Space Agency, are interested in answering. Analogue missions on Earth help researchers understand how to do their jobs while faced with the many challenges that arise because of the hostile environment of space.

Mars on Earth

The Biologic Analog Science Associated with Lava Terrains (BASALT) research program explores and collects samples from places on Earth that are analogous to Martian environments. Building off similar previous analogue studies in Canada and the U.S., the BASALT program operates under simulated Mars mission conditions. Merging scientific, technical and operational research objectives, the insights gained during two major analogue mission deployments are detailed in a special issue of the journal Astrobiology.

Mission to Mars - YouTube
An overview of McMaster University’s BASALT Project.

Human exploration of Mars adds in a dynamic that doesn’t exist when using rovers. Unlike a rover, a human can make decisions and respond to new unexpected discoveries during an extravehicular activity (EVA). This flexibility is valuable for scientific discovery but presents some challenges for planning EVAs. An important aspect of Mars exploration will be making decisions about which rock samples to collect that will help answer scientific questions about the history of Mars. While crews will receive training in geology and biology, expert scientists on Earth are available to help them make those decisions.

But don’t forget the unavoidable communications delay between Earth and Mars.

Communication time lag

Simulated EVAs were conducted in two Mars analogue environments: Hawai’i Volcanoes National Park and Craters of the Moon National Monument and Preserve in Idaho. Scientists think that early Mars once had volcanic activity that could have created the kinds of habitats that we know contain life on Earth.

These two field sites were chosen as they represent past and present conditions on Mars. Scientists can then try to understand the link between biology and the geological characteristics to identify sampling locations for astrobiological studies.

Ideally, these would be geological features that can be seen from Earth’s orbit, allowing Mars researchers to look for these same features and identify points of interest for future missions.

A satellite image of the Craters of the Moon National Monument, taken by NASA’s Landsat program in 2000. NASA Simulating the Mars environment

Planning a mission to Mars, even a simulated one, is no easy task.

First and foremost, the questions that guided the research were not simulated in any way: these were real questions asked about how microbes live in and interact with volcanic rocks.

I am a geobiologist and my expertise is in organic geochemistry. I want to know what microbes do in the environment and, importantly for astrobiology, what signs they leave behind. Within the BASALT program my research required that the samples were collected in a sterile manner, adding another complex layer to an already complex series of activities that must be done while facing the challenges of being in space.

Deviations from sampling protocols or not collecting enough contextual data about the sampling sites would have consequences for the validity of the results.

The BASALT team on site in Hawai'i. Zara Mirmalek, Author provided

The BASALT team spent months planning the field deployments down to the last detail, including how many photos to take and estimating how long it might take to sample each rock. Individual sample sites in Idaho and Hawai’i were selected based on remote-sensing information available to the team (akin to using orbital satellite data to select landing locations on Mars).

At each site, people working on the surface (an extravehicular crew) gathered information and sent it to a crew in the who stayed in the space habitat (the intravehicular crew). Information gathered was then sent back to Earth. The intravehicular crew was the go-between, interacting in real-time with the extravehicular crew.

On Mars, once astronauts are on the ground, they would follow pre-planned traverses and search for basalt rocks that would be used by the scientists for research.

Communicating findings

A great deal of thought went into not only the type of data that the Mars crew would collect and send back to Earth for the scientists to examine, but also how they would then work with it and come to a decision about which rock they wanted the crew on Mars to sample. This could be affected by the conditions for communications including the bandwidth available: if low bandwidth conditions exist that limit transmission of data, could photos be used in place of high-resolution video? It’s like internet speed, if your connection is extremely slow you may rethink watching Netflix but you might still download those cat photos.

The BASALT program showed that it is possible to receive useful input from an Earth-based team over time delay. At the end of the program we learned quite a bit about how to effectively do this. For example, while video is helpful, high resolution photos are the preferred choice under bandwidth restrictions. Text, rather than voice communications were best for relaying important decisions between Earth and Mars. These and other results will be used to plan missions so that when we send humans to Mars we are doing the best possible job to answer fundamental questions about whether life ever existed there.







About The Author:

Allyson Brady is a Postdoctoral fellow at McMaster University

This article is republished from our content partners at The Conversation under a Creative Commons license. 

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by Adrienne Mayor

Two small figures guard the table holding the Buddha’s relics. Are they spearmen, or robots? British Museum, CC BY-NC-SA


As early as Homer, more than 2,500 years ago, Greek mythology explored the idea of automatons and self-moving devices. By the third century B.C., engineers in Hellenistic Alexandria, in Egypt, were building real mechanical robots and machines. And such science fictions and historical technologies were not unique to Greco-Roman culture.

In my recent book “Gods and Robots,” I explain that many ancient societies imagined and constructed automatons. Chinese chronicles tell of emperors fooled by realistic androids and describe artificial servants crafted in the second century by the female inventor Huang Yueying. Techno-marvels, such as flying war chariots and animated beings, also appear in Hindu epics. One of the most intriguing stories from India tells how robots once guarded Buddha’s relics. As fanciful as it might sound to modern ears, this tale has a strong basis in links between ancient Greece and ancient India.

The story is set in the time of kings Ajatasatru and Asoka. Ajatasatru, who reigned from 492 to 460 B.C., was recognized for commissioning new military inventions, such as powerful catapults and a mechanized war chariot with whirling blades. When Buddha died, Ajatasatru was entrusted with defending his precious remains. The king hid them in an underground chamber near his capital, Pataliputta (now Patna) in northeastern India.

A sculpture depicting the distribution of the Buddha’s relics. Los Angeles County Museum of Art/Wikimedia Commons

Traditionally, statues of giant warriors stood on guard near treasures. But in the legend, Ajatasatru’s guards were extraordinary: They were robots. In India, automatons or mechanical beings that could move on their own were called “bhuta vahana yanta,” or “spirit movement machines” in Pali and Sanskrit. According to the story, it was foretold that Ajatasatru’s robots would remain on duty until a future king would distribute Buddha’s relics throughout the realm.

Ancient robots and automatons A statue of Visvakarman, the engineer of the universe. Suraj Belbase/Wikimedia Commons, CC BY-SA

Hindu and Buddhist texts describe the automaton warriors whirling like the wind, slashing intruders with swords, recalling Ajatasatru’s war chariots with spinning blades. In some versions the robots are driven by a water wheel or made by Visvakarman, the Hindu engineer god. But the most striking version came by a tangled route to the “Lokapannatti” of Burma – Pali translations of older, lost Sanskrit texts, only known from Chinese translations, each drawing on earlier oral traditions.

In this tale, many “yantakara,” robot makers, lived in the Western land of the “Yavanas,” Greek-speakers, in “Roma-visaya,” the Indian name for the Greco-Roman culture of the Mediterranean world. The Yavanas’ secret technology of robots was closely guarded. The robots of Roma-visaya carried out trade and farming and captured and executed criminals.

Robot makers were forbidden to leave or reveal their secrets – if they did, robotic assassins pursued and killed them. Rumors of the fabulous robots reached India, inspiring a young artisan of Pataliputta, Ajatasatru’s capital, who wished to learn how to make automatons.

In the legend, the young man of Pataliputta finds himself reincarnated in the heart of Roma-visaya. He marries the daughter of the master robot maker and learns his craft. One day he steals plans for making robots, and hatches a plot to get them back to India.

Certain of being slain by killer robots before he could make the trip himself, he slits open his thigh, inserts the drawings under his skin and sews himself back up. Then he tells his son to make sure his body makes it back to Pataliputta, and starts the journey. He’s caught and killed, but his son recovers his body and brings it to Pataliputta.

Once back in India, the son retrieves the plans from his father’s body, and follows their instructions to build the automated soldiers for King Ajatasatru to protect Buddha’s relics in the underground chamber. Well hidden and expertly guarded, the relics – and robots – fell into obscurity.

The sprawling Maurya Empire in about 250 B.C. Avantiputra7/Wikimedia Commons, CC BY-SA

Two centuries after Ajatasatru, Asoka ruled the powerful Mauryan Empire in Pataliputta, 273-232 B.C. Asoka constructed many stupas to enshrine Buddha’s relics across his vast kingdom. According to the legend, Asoka had heard the legend of the hidden relics and searched until he discovered the underground chamber guarded by the fierce android warriors. Violent battles raged between Asoka and the robots.

In one version, the god Visvakarman helped Asoka to defeat them by shooting arrows into the bolts that held the spinning constructions together; in another tale, the old engineer’s son explained how to disable and control the robots. At any rate, Asoka ended up commanding the army of automatons himself.

Exchange between East and West

Is this legend simply fantasy? Or could the tale have coalesced around early cultural exchanges between East and West? The story clearly connects the mechanical beings defending Buddha’s relics to automatons of Roma-visaya, the Greek-influenced West. How ancient is the tale? Most scholars assume it arose in medieval Islamic and European times.

But I think the story could be much older. The historical setting points to technological exchange between Mauryan and Hellenistic cultures. Contact between India and Greece began in the fifth century B.C., a time when Ajatasatru’s engineers created novel war machines. Greco-Buddhist cultural exchange intensified after Alexander the Great’s campaigns in northern India.

Inscriptions in Greek and Aramaic on a monument originally erected by King Asoka at Kandahar, in what is today Afghanistan. World Imaging/Wikimedia Commons

In 300 B.C., two Greek ambassadors, Megasthenes and Deimachus, resided in Pataliputta, which boasted Greek-influenced art and architecture and was the home of the legendary artisan who obtained plans for robots in Roma-visaya. Grand pillars erected by Asoka are inscribed in ancient Greek and name Hellenistic kings, demonstrating Asoka’s relationship with the West. Historians know that Asoka corresponded with Hellenistic rulers, including Ptolemy II Philadelphus in Alexandria, whose spectacular procession in 279 B.C. famously displayed complex animated statues and automated devices.

Historians report that Asoka sent envoys to Alexandria, and Ptolemy II sent ambassadors to Asoka in Pataliputta. It was customary for diplomats to present splendid gifts to show off cultural achievements. Did they bring plans or miniature models of automatons and other mechanical devices?

I cannot hope to pinpoint the original date of the legend, but it is plausible that the idea of robots guarding Buddha’s relics melds both real and imagined engineering feats from the time of Ajatasatru and Asoka. This striking legend is proof that the concepts of building automatons were widespread in antiquity and reveals the universal and timeless link between imagination and science.








About The Author:

Adrienne Mayor is a Research Scholar, Classics and History and Philosophy of Science at Stanford University. She is also the author of: Gods and Robots: Myths, Machines, and Ancient Dreams of Technology

Princeton University Press provides funding as a member of The Conversation US.

This article is republished from our content partners at The Conversation under a Creative Commons license. 

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An international team of astronomers, led by University of Hawaii graduate student Ashley Chontos, announced the confirmation of the first exoplanet candidate identified by NASA’s Kepler Mission. The result was presented at the fifth Kepler/K2 Science Conference held in Glendale, CA.

Launched almost exactly 10 years ago, the Kepler Space Telescope has discovered thousands of exoplanets using the transit method – small dips in a star’s brightness as planets cross in front of the star. Because other phenomena can mimic transits, Kepler data reveal planet candidates, but further analysis is required to confirm them as genuine planets.

Despite being the very first planet candidate discovered by NASA’s Kepler Space Telescope, the object now known as Kepler-1658 b had a rocky road to confirmation. The initial estimate of the size of the planet’s host star was incorrect, so the sizes of both the star and Kepler-1658 b were vastly underestimated. It was later set aside as a false positive when the numbers didn’t quite make sense for the effects seen on its star for a body of that size. Fortuitously, Chontos’ first year graduate research project, which focused on re-analyzing Kepler host stars, happened at just the right time.

“Our new analysis, which uses stellar sound waves observed in the Kepler data to characterize the host star, demonstrated that the star is in fact three times larger than previously thought. This in turn means that the planet is three times larger, revealing that Kepler-1658 b is actually a hot Jupiter-like planet,” said Chontos. With this refined analysis, everything pointed to the object truly being a planet, but confirmation from new observations was still needed.

“We alerted Dave Latham (a senior astronomer at the Smithsonian Astrophysical Observatory, and co-author on the paper) and his team collected the necessary spectroscopic data to unambiguously show that Kepler-1658 b is a planet,” said Dan Huber, co-author and astronomer at the University of Hawaii. “As one of the pioneers of exoplanet science and a key figure behind the Kepler mission, it was particularly fitting to have Dave be part of this confirmation.”

Kepler-1658 is 50% more massive and three times larger than the Sun. The newly confirmed planet orbits at a distance of only twice the star’s diameter, making it one of the closest-in planets around a more evolved star – one that resembles a future version of our Sun. Standing on the planet, the star would appear 60 times larger in diameter than the Sun as seen from Earth.

Planets orbiting evolved stars similar to Kepler-1658 are rare, and the reason for this absence is poorly understood. The extreme nature of the Kepler-1658 system allows astronomers to place new constraints on the complex physical interactions that can cause planets to spiral into their host stars. The insights gained from Kepler-1658b suggest that this process happens slower than previously thought, and therefore may not be the primary reason for the lack of planets around more evolved stars.

“Kepler-1658 is a perfect example of why a better understanding of host stars of exoplanets is so important.” said Chontos. “It also tells us that there are many treasures left to be found in the Kepler data.”

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In his Special Theory of Relativity, Einstein formulated the hypothesis according to which the speed of light is always the same, no matter what the conditions are. It may, however, be possible that – according to theoretical models of quantum gravitation – this uniformity of space-time does not apply to particles. Physicists have now tested this hypothesis with a first long-term comparison of two optical ytterbium clocks at the Physikalisch-Technische Bundesanstalt (PTB). With these clocks, whose error amounts to only one second in ten billion years, it should be possible to measure even extremely small deviations of the movement of the electrons in ytterbium. But the scientists did not detect any change when the clocks were oriented differently in space. Due to this result, the current limit for testing the space-time symmetry by means of experiments has been drastically improved by a factor of 100. In addition to this, the extremely small systematic measurement uncertainty of the optical ytterbium clocks of less than 4 × 10E-18 has been confirmed. The team consisting of physicists from PTB and from the University of Delaware has published its results in the current issue of Nature.

It is one of the most famous physics experiments in history: As early as 1887, Michelson and Morley demonstrated what Einstein later expressed in the form of a theory. With the aid of a rotating interferometer, they compared the speed of light along two optical axes running vertically to each other. The result of this experiment became one of the fundamental statements of Einstein’s Special Theory of Relativity: The speed of light is the same in all directions of space. Now one could ask: Does this symmetry of space (which was named after Hendrik Antoon Lorentz) also apply to the motion of material particles? Or are there any directions along which these particles move faster or more slowly although the energy remains the same? Especially for high energies of the particles, theoretical models of quantum gravitation predict a violation of the Lorentz symmetry.

Now an experiment has been carried out with two atomic clocks in order to investigate this question with high accuracy. The frequencies of these atomic clocks are each controlled by the resonance frequency of a single Yb+ ion that is stored in a trap. While the electrons of the Yb+ ions have a spherically symmetric distribution in the ground state, in the excited state they exhibit a distinctly elongated wave function and therefore move mainly along one spatial direction. The orientation of the wave function is determined by a magnetic field applied inside the clock. The field orientation was chosen to be approximately at right angles in the two clocks. The clocks are firmly mounted in a laboratory and rotate together with the Earth once a day (more exactly: once in 23.9345 hours) relative to the fixed stars. If the electrons’ speed depended on the orientation in space, this would thus result in a frequency difference between the two atomic clocks that would occur periodically, together with the Earth’s rotation. To be able to differentiate such an effect clearly from any possible technical influences, the frequencies of the Yb+ clocks were compared for more than 1000 hours. During the experiment, no change between the two clocks was observed for the accessible range of period durations from a few minutes up to 80 hours. For the theoretical interpretation and calculations concerning the atomic structure of the Yb+ ion, PTB’s team worked in collaboration with theoreticians from the University of Delaware (USA). The results that have now been obtained have improved the limits set in 2015 by researchers from the University of California, Berkeley with Ca+ ions drastically by a factor of 100.

Averaged over the total measuring time, both clocks exhibited a relative frequency deviation of less than 3 × 10E-18. This confirms the combined uncertainty of the clock that had previously been estimated to be 4 × 10E-18. Furthermore, it is an important step in the characterization of optical atomic clocks at this level of accuracy. Only after roughly ten billion years would these clocks potentially deviate from each other by one second.

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by Hany Farid

Nope, not a real news report from Hurricane Irma. Snopes


One month before the 2016 U.S. presidential election, an “Access Hollywood” recording of Donald Trump was released in which he was heard lewdly talking about women. The then-candidate and his campaign apologized and dismissed the remarks as harmless.

At the time, the authenticity of the recording was never questioned. Just two years later, the public finds itself in a dramatically different landscape in terms of believing what it sees and hears.

Advances in artificial intelligence have made it easier to create compelling and sophisticated fake images, videos and audio recordings. Meanwhile, misinformation proliferates on social media, and a polarized public may have become accustomed to being fed news that conforms to their worldview.

All contribute to a climate in which it is increasingly more difficult to believe what you see and hear online.

There are some things that you can do to protect yourself from falling for a hoax. As the author of the upcoming book “Fake Photos,” to be published in August, I’d like to offer a few tips to protect yourself from falling for a hoax.

1. Check if the image has already been debunked

Many fake images are recirculated and have previously been debunked. A reverse image search is a simple and effective way to see how an image has previously been used.

Unlike a typical internet search in which keywords are specified, a reverse image search on Google or TinEye can search for the same or similar images in a vast database.

Reverse image search engines cannot exhaustively index the vastly expansive, ever-changing content on the internet. So, even if the image is on the internet, there is no guarantee that it will have been found by the site. In this regard, not finding an image doesn’t mean it’s real – or fake.

You can improve the likelihood of a match by cropping the image to contain only the region of interest. Because this search requires you to upload images to a commercial site, take care when uploading any sensitive images.

2. Check the metadata

Digital images often contain rich metadata that can provide clues as to their provenance and authenticity.

Metadata is data about data. The metadata for a digital image includes the camera make and model; camera settings like aperture size and exposure time; the date and time when the image was captured; the GPS location where the image was captured; and much more.

EXIF data offers clues about this photograph of a flower. Original image from Andreas Dobler/Wikimedia, CC BY-SA

The importance of the date, time and location tags is self-evident. Other tags may have a similarly straightforward interpretation. For example, photo-editing software may introduce a tag that identifies the software, or date and time tags that are inconsistent with other tags.

Several tags provide information about camera settings. A gross inconsistency between the image properties implied by these settings and the actual properties of the image provides evidence that the image has been manipulated. For example, the exposure time and aperture size tags provide a qualitative measure of the light levels in the photographed scene. A short exposure time and small aperture suggest a scene with high light levels taken during the day, while a long exposure time and large aperture suggest a scene with low light levels taken at night or indoors.

The metadata is stored in the image file and can be readily extracted with various programs. However, some online services strip out much of an image’s metadata, so the absence of metadata is not uncommon. When the metadata is intact, however, it can be highly informative.

3. Recognize what can and can’t be faked

When assessing if an image or video is authentic, it is important to understand what is and what is not possible to fake.

For example, an image of two people standing shoulder to shoulder is relatively easy to create by splicing together two images. So is an image of a shark swimming next to a surfer. On the other hand, an image of two people embracing is harder to create, because the complex interaction is difficult to fake.

While modern artificial intelligence can produce highly compelling fakes – often called deepfakes – this is primarily restricted to changing the face and voice in a video, not the entire body. So it is possible to create a good fake of someone saying something that they never did, but not necessarily performing a physical act that they never did. This, however, will surely change in the coming years.

4. Beware of sharks

After more than two decades in digital forensics, I’ve come to the conclusion that viral images with sharks are almost always fake. Beware of spectacular shark photos.

5. Help fight misinformation

Fake images and videos have led to horrific violence around the globe, manipulation of democratic elections and civil unrest. The prevalence of misinformation also now allows anyone to cry “fake news” in response to any news story with which they disagree.

I believe that it’s critical for the technology sector to make broad and deep changes to content moderation policies. The titans of tech can no longer ignore the direct and measurable harm that has come from the weaponization of their products.

What’s more, those who are developing technology that can be used to easily create sophisticated fakes must think more carefully about how their technology can be abused and how to put some safeguards in place to prevent abuse. And, the digital forensic community must continue to develop tools to quickly and accurately detect fake images, videos and audio.

Lastly, everyone must change how they consume and spread content online. When reading stories online, be diligent and consider the source; the New York Evening (a fake news site) is not the same as The New York Times. Always be cautious of the wonderfully satirical stories from The Onion that often get mistaken for real news.

Check the date of each story. Many fake stories continue to recirculate years after their introduction, like a nasty virus that just won’t die. Recognize that many headlines are designed to grab your attention – read beyond the headline to make sure that the story is what it appears to be. The news that you read on social media is algorithmically fed to you based on your prior consumption, creating an echo chamber that exposes you only to stories that conform to your existing views.

Finally, extraordinary claims require extraordinary evidence. Make every effort to fact-check stories with reliable secondary and tertiary sources, particularly before sharing.









About The Author:

Hany Farid is  Professor of Computer Science at Dartmouth College and is the author of Photo Forensics.

MIT Press provides funding as a member of The Conversation US.

This article is republished from our content partners at The Conversation under a Creative Commons license. 

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Marvel Studios' Avengers: Endgame - Official Trailer - YouTube


TRAILER 2: “AVENGERS ENDGAME” (2019)

If you’ve enjoyed any of the movies Marvel Studios have released over the first 10 years, it looks like there is a good chance you will enjoy  “Endgame”. There’s footage from some of the earlier films,  some new footage, as well as some new faces!

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