Dark Matter's New Wrinkle: It May Behave Like Wavy Fluid

The mysterious dark matter that makes up most of the matter in the universe may behave more like wavy fluids than solid particles, helping to explain the shapes of galaxies, a new study suggests.

Dark matter is one of the greatest mysteries in the cosmos. It is thought to be an invisible and mostly intangible substance that makes up five-sixths of all matter in the universe.

The scientific consensus is that dark matter is composed of a new type of particle, one that interacts very weakly with all the known forces of the universe and is mostly only detectable via the gravitational pull it exerts. However, what kind of particle dark matter consists of remains unknown. 

There are two known types of particles in the universe, fermions and bosons. Fermions include particles such as protons, neutrons and electrons, while bosons include particles such as the photons that make up light.

The mainstream focus for dark matter has been on massive fermions, said study co-author Tom Broadhurst, a cosmologist at the University of the Basque Country in Spain. However, so far these fermion candidates for dark matter have not been generated by the Large Hadron Collider  (LHC), the most powerful particle accelerator on Earth, nor have any been confirmed by the Large Underground Xenon (LUX) experiment, the most sensitive dark-matter detector ever built.

As a result, some researchers have suggested that dark matter might not be made of extremely high-mass heavy fermions, but low-mass light bosons instead. For instance, Broadhurst and his colleagues investigated the behavior of a boson with a mass of less than 10^-22 electron-volts, or less than a tenth of a billionth of a billionth of billionth the mass of an electron.

The difference between fermions and bosons is that a fermion cannot occupy the same state at the same time as another fermion. As an analogy, a state is like a seat, and two or more fermions cannot sit in the same seat simultaneously. In contrast, two or more bosons can occupy the same state at the same time, and can therefore clump into so-called Bose-Einstein condensates that act like single blobs.

Now, Broadhurst and his colleagues have for the first time simulated what galaxies might look like if dark matter was made of light bosons. They said their models more accurately reflect what galaxies actually look like than more conventional models where dark matter is made of fermions.

The researchers investigated dwarf spheroidal galaxies, the smallest and most common class of galaxy, which have centers with masses equal to about 10 million suns. The basic properties of dwarf spheroidal galaxies are very difficult to explain with simulations in which dark matter is made of heavy fermions; these models suggest that much smaller galaxies should exist than what astronomers see, and that dark matter in dwarf spheroidal galaxies should be much less smoothly distributed than what is observed.

Broadhurst and his colleagues simulated the way the gravitational pull of dark matter Bose-Einstein condensates influences the evolution of galaxies. They found these simulated blobs of dark matter led to galaxies that better matched the ones that astronomers see.

The scientists found these dark matter Bose-Einstein condensates are full of waves. Stable waves known as soliton waves are expected in the middle of galaxies, "surrounded by extended lumpy halos of dark matter comprised of giant quantum density fluctuations that fluctuate over time," Broadhurst said. This behavior can help explain both the size of the dwarf spheroidal galaxies seen and why dark matter is distributed relatively smoothly within them.

Another consequence of dark matter Bose-Einstein condensates is that galaxy formation should have begun about 330 million years after the Big Bang. This is substantially delayed compared to models that envision dark matter being made of fermions, which suggest that galaxy formation should have begun about 50 million years after the Big Bang. Future observations by NASA's Hubble Space Telescope could help determine whether dark matter consists of fermions or bosons, study team members said.

Broadhurst and his colleagues Hsi-Yu Schive and Tzihong Chiueh detailed their findings in June in the journal Nature Physics.

Orion on the Pad: NASA Rolls Out Space Capsule for 1st Test Flight

CAPE CANAVERAL, Fla. — NASA's first space-bound Orion capsule has arrived at the launch pad, where it will lift off in early December on an uncrewed test flight in support of NASA's plans for future astronaut missions beyond Earth orbit.

The gumdrop-shaped spacecraft, encased within a white aerodynamic shell and topped by a launch escape tower, rolled up to the base of Space Launch Complex 37B at the Cape Canaveral Air Force Station in Florida.

The capsule, which is set to embark on Dec. 4 on NASA's Exploration Flight Test-1 (EFT-1), rode out to the pad atop a multi-wheeled transporter. A banner hung on the front of the vehicle read, "Neil Armstrong Operations & Checkout Building 'I'm On Board,'" referencing the building where the spacecraft was assembled. 

"I gotta tell you, this is special," Bob Cabana, the director of NASA's Kennedy Space Center and a former astronaut, told reporters during a press conference on Monday . "This is our first step on the journey to Mars."

"To see the vehicle on top of the service module with the launch abort system attached, it is quite a stack," Cabana continued. "And it is going to look really good on top of the Delta IV [rocket]."

The Orion's journey to the pad began on Tuesday night at 8:54 p.m. EST) at a hangar some 22 miles (35 kilometers) away at the Kennedy Space Center.

"To see the actual vehicle, the first [Orion] that is going to fly, is an amazing sight," Rex Walheim, a NASA astronaut who flew onboard the final space shuttle mission and now represents the astronaut office in the Orion program, told collectSPACE. "It just looks beautiful and it is just so nice seeing us get a new vehicle to the launch pad."

The six-hour rollout originated at the Launch Abort System Facility, where the Orion spacecraft was equipped with its escape system tower and enveloped within its outer shell "ogive" panels.

The Exploration Flight Test-1 mission will see the in-flight separation of these components from the Orion as part of the mission's test objectives.

"EFT-1 is basically a compilation of what I would say are the riskiest events we're going to see when we fly people," Mark Geyer, NASA's Orion program manager, said during a press conference held Thursday (Nov. 6). "So this test flight is a great opportunity for us to fly those and actually see them in operation."

"Some of these [mission] events are very difficult or even impossible to test on the ground, so it is important that we fly them," Geyer continued. "EFT-1 gives us a chance to put all those together in a test flight."

On the way out to SLC-37B, the Orion paused in front of the 52-story-tall Vehicle Assembly Building, where NASA plans to assemble its Space Launch System rockets that will fly Orion on future missions out to the vicinity of the moon and eventually to Mars. The capsule also rolled past Pad 39B, where the space agency's Saturn V moon-bound rockets and space shuttles left Earth, and from where the SLS will launch.

Now at its departure site, the 72-foot-tall (22-meter) Orion, complete with its booster adapter section, will be hoisted 170 feet (52 meters) into the air and mounted to the United Launch Alliance Delta IV Heavy rocket that will launch it into Earth orbit. The EFT-1 mission is scheduled to lift off , just after sunrise.

The flight test will take the Orion 15 times farther out into space than the International Space Station on a four-and-a-half-hour mission to test many of the systems critical for human missions into deep space. After circling the planet twice, the Orion will reenter Earth's atmosphere at 20,000 miles per hour before descending under parachutes to a splashdown in the Pacific Ocean.

Google Leases NASA's Moffett Field, Historic Hangar for $1.2 Billion

A Google subsidiary will lease a NASA facility in California's Bay Area for $1.16 billion over the next 60 years, agency officials announced Monday (Nov. 10).

Planetary Ventures, LLC will lease Moffett Federal Airfield (MFA), which is currently managed by NASA's Ames Research Center, and restore the facility's historic Hangar One, a huge building that has been a Silicon Valley landmark since the 1930s.

"As NASA expands its presence in space, we are making strides to reduce our footprint here on Earth," NASA Administrator Charles Bolden said in a statement. "We want to invest taxpayer resources in scientific discovery, technology development and space exploration — not in maintaining infrastructure we no longer need. Moffett Field plays an important role in the Bay Area and is poised to continue to do so through this lease arrangement."

The agreement should save NASA $6.3 million per year in operations costs on top of the lease value, agency officials said.

Planetary Ventures will invest more than $200 million in the 1,000-acre (405 hectares) property, which also includes Hangar Two and Hangar Three, two runways, a flight-operations building, and a private golf course.

The company will refurbish all three hangars and use them as research facilities in an attempt to develop new technologies in space exploration, robotics and other high-tech fields, NASA officials said. Planetary Ventures will also establish a facility on the site that will teach the public about MFA's historical significance.

"We look forward to rolling up our sleeves to restore the remarkable landmark Hangar One, which for years has been considered one of the most endangered historic sites in the United States," said David Radcliffe, Vice President of Real Estate and Workplace Services at Google.

Ames is NASA's lead center for supercomputing and has helmed a number of important missions over the years, including the planet-hunting Kepler space telescope and the Lunar Atmosphere and Dust Environment Explorer (LADEE) probe, which studied the moon's wispy atmosphere after launching in September 2013.

'Muscles' Triggered by Electricity Could Power Tiny Robots

Tiny electrically activated "muscles" could one day give rise to microscopic robots that are smaller than a grain of sand, researchers say.

The chains of particles that make up these muscles could also lead to electronics that can automatically rewire themselves as desired, scientists added.

Microscopic robots, or microbots, could one day swim inside the body to fight disease or crawl into bombs to defuse them, among many other applications. "They could work together and go places that have never been possible before," said study co-author Michael Solomon, a chemical engineer at the University of Michigan at Ann Arbor.

However, building these robots and making them mobile remain two major challenges. "If you imagine a microscale robot in the future, it would need ways to move autonomously and it would need to be able to exert forces, by pushing or pulling on other objects," Solomon said.

Now, researchers suggest muscles created from self-assembling chains of microscopic particles could help power microbots in the future. The scientists detailed their findings online today (Nov. 10) in the journal Nature Materials.

The researchers started with spherical particles made up of a combination of polystyrene, the plastic material used in Styrofoam. They stretched these particles in a machine until they were the shape of rice grains, about 0.6 microns wide and 3 microns long. (In comparison, the average width of a human hair is about 100 microns.)

The scientists coated one side of each particle with gold. A particle with two different faces is known as a Janus particle, named after the two-faced Roman god Janus.

The gilded halves of the Janus particles attracted each other in salty water — the more salt in the water, the stronger the attraction. The ideal concentration of salt was about half that found in the sports drink Powerade, the researchers said.

On their own, the particles formed short chains of overlapping pairs, averaging about 50 to 60 particles per chain. However, when exposed to an alternating electric current, the chains elongated, seeming to add new particles indefinitely.

By expanding and contracting, these fibers could work like little muscles, said study co-author Sharon Glotzer, a computational physicist and chemical engineer at the University of Michigan at Ann Arbor. "We have extended and retracted them many times," Solomon said. "The degree of control we have over the chains is exciting."

"The findings point the way toward a new class of reconfigurable materials made of micron-size particles — materials that can be triggered to morph and change shape in response to changes in environment or on demand," Glotzer told Live Science.

The scientists found that gold plating and alternating electric current could make the chains extend by about 36 percent.

"The gold-gold bond between particles that stabilizes the chains is very strong — it would be very hard to pull the chains apart if they were gripped from the side," Solomon told Live Science. "However, the force required for the particles to slip past each other along the chain is not as great. The alternating-current field provides enough force for the particles to slide past each other, locking them into a new, extended configuration."

Although the force generated by the fibers is about 1,000 times weaker than human muscle tissue per unit area, it may be enough for microbots. "The next step is to organize groups of these chains into bundles," Solomon said. "If we can get the chains to swarm together, we can get them to lift loads, move around, do things that biological muscles do."

Microbots powered by muscles are likely many years away, but in the meantime, the Janus particles could lead to electronics that rewire themselves on demand, the researchers said.

"These chains are essentially wires, so you could assemble them into a circuit for reconfigurable electronics," Solomon said in a statement.

MICROSOFT EYES WHITE SPACE TECH TO PROVIDE FREE INTERNET IN INDIA

Tech giants such as Facebook and Google are already making efforts (with their Internet beaming drone and balloon projects) to provide Internet access in areas that still don't have it. Soon, Microsoft will join the bandwagon as it plans to use “white space” - unused spectrum between two TV channels – to provide Internet connectivity in remote areas of India.

“Wifi has a range of only about 100 metres, whereas the 200-300 MHz spectrum band available in the white space can reach up to 10 km,” Bhaskar Pramanik, chairman, Microsoft India is quoted as saying. “This spectrum belongs mainly to Doordarshan and the government and is not used at all. We have sought clearance for a pilot project in two districts.”

“The challenge is the lack of digital infrastructure across India. This initiative addresses this challenge in a cost-effective manner and creates an eco-system that will benefit everyone, including manufacturers of routers and other technology devices, other technology companies, besides Microsoft,” Pramanik said.

Microsoft’s new initiative could provide a huge boost to the Indian government's Make in India and Digital India campaigns. Microsoft has shown keen interest in being part of the movements.

White space, in telecommunications, is referred to the frequencies allotted to a broadcasting service but is unused. The unused frequencies are considered to have potential for provide wireless broadband Internet access. A device that can be used with such tech is called "white-space device” (WSD). White space tech is expected to push Internet connectivity in rural areas. Read more about White Space radio here.

As far as India goes, the new Modi-led government has given a high priority to the IT sector. Under its ambitious digital India campaign, the government wants to connect about 2.5 lakh panchayats across the country with broadband, and plans to build a broadband highway in the country.

As said above, Microsoft is not alone in its efforts to push Internet connectivity in remote and rural areas. Facebook is already working on drones to beam internet connections to people down here on earth. Google's project Loon envisages providing Internet access through high-altitude balloons placed in the stratosphere. According to reports, the Indian government has shown a 'great interest' in its 'Project Loon'.

Source: Hindustan Times

SAMSUNG PLANS TO LAUNCH FIRST TIZEN OS PHONES IN INDIA

According to reports, Samsung is planning to launch a new range of budget devices in India based on its home-grown Tizen operating system. The smartphone is expected to be launched within a month.

Samsung's Tizen OS based smartphone will feature a 4-inch display, dual SIM functionality and integrated FM Radio. It will have a 3.2 MP rear camera and 512 MB of RAM. It will have 4 GB internal memory expandable up to 32 GB via microSD card support. The device is expected to be affordably priced between Rs 5,000 and Rs 15,000. Samsung has declined to comment and says that the news is "market speculation."

Reports stated that Samsung has made India the launch pad for its Samsung Tizen OS as it has been under pressure in the domestic smartphone market because of increased competition from brands like Micromax.

According to a recent Gfk report, Samsung's smartphone market share in India fell to just over 32% in August from around 32.5% in July, but recovered approximately 33% in September, thanks to new devices in the budget segment. The report highlighted that although Samsung retained the top spot, Micromax, Nokia, Lava and Karbonn have also gained a lot of market share.

Emerging markets like India are becoming the focus of technology giants to market their offerings. Recently Internet giant Google unveiled its budget Android One devices in the country, while Intex launched Mozilla OS-based affordable smartphones. Other electronics giant like Xiaomi and Panasonic have also launched budget devices under Rs. 15,000 in India, in a bid to gain market share.

Source: ET      

MOTO X (2ND GEN) WILL BE 1ST PHONE TO GET ANDROID 5.0 LOLLIPOP

Guess who just beat Google to its own update? Motorola has pushed out the Android 5.0 Lollipop update to its MotoX (2nd Gen) smartphone. The maker of the Nexus 6 was also first off the mark to announce the Lollipop update for its devices. The company has given the updates to its ‘Soak Test’ users, bringing all the features of Lollipop to its newest flagship smartphone.

Motorola has already announced the Lollipop update for its Moto X (2nd Gen and 1st Gen), Moto G (2nd Gen and 1st Gen), Moto E and some Droid series smartphones. In addition, the Droid Turbo, or the Moto Maxx, as it is known in its international avataar, is also sure to get the update to the new version.

Currently, the company has sent out updates to the ‘Pure’ edition of the new Moto X. This is an unlocked version of the device. In addition, the update is currently available to users who had signed up for the Motorola Feedback Network and opted in to its ‘Soak Test’ initiative. The company is presumably using this to test out the update before sending it out to all its users. Below is a video of the Moto X (2nd Gen) running Lollipop, published by Droid Life on YouTube.

Interestingly, another Nexus maker, LG, which made the Nexus 4 and Nexus 5 smartphones has also announced the update for its current flagship, the LG G3. The company has started rolling out the update to some of its users in Poland and has announced that it will be doing so to others over the next week.

GOOGLE'S PROJECT ARA SMARTPHONES MAY BE ABLE TO MONITOR YOUR BLOOD OXYGEN LEVELS

It was revealed recently that Google's much anticipated Project Ara will have swappable health related accessories, one of which is a Pulse Oximeter. The Pulse Oximeter will allow the smartphone to measure oxygen levels in your blood. This woill increase the potential of the yet to be announced smartphone and extend its capabilities to be used as mobile health monitors.

Google’s Project Ara is making heads turn since the first prototype was unveiled as it has swappable internals. The Project, which was originally headed by Motorola Mobility, became Google’s pet project after Motorola was sold off to Lenovo.

Google's Project Ara is expected to come though with a phone early next year but we are skeptical over the number of swappable accessories in the final product. The phone most probably will be available as a base skeleton on which multiple swappable parts could be added later on.

Source:ubergizmo

APPLE OFFERS SOLUTION FOR MISSING TEXT MESSAGES PROBLEM

Technology giant Apple has released a tool that will allow iOS users to de-register their phone number from Apple's proprietary iMessage service, to stop text messages from disappearing when a user switches to a non-Apple device.

Apple has included step-by-step instructions for de-registering iPhones from the iMessage service if the owner still uses their iPhone. It also gives the user an option where they can type in their phone number and receive a confirmation code that can be entered to confirm their intent, if they have switched to another platform. Once they receive the confirmation code on their cell phone, users can enter it at Apple's website, to delist from iMessage. After that, the messages sent from the iOS devices will automatically switch to the standard SMS or MMS messages rather than iMessage.

Apple introduced the iMessage service in 2011. The feature helps iPhone users to communicate with one another over Wi-Fi or data networks, as an alternative to using text messages on cellular networks. However, once the users switches from their iPhone to an Android or Windows device the messages disappear. Unhappy users have even sued the technology giant over the matter.

Earlier this year, Apple had stated that it planned to make it easier for people to delist their account from iMessage. Unlike BlackBerry's BBM or Google Hangouts, which can be accessed on competing devices via third-party applications, Apple's iMessage service is still exclusive to Apple devices.

Source: Apple

FACEBOOK GIVES USERS MORE CONTROL ON NEWS FEED

Facebook has rolled out new filters in settings that gives users more control over what they see on their News Feeds. The new settings are launched on desktop and will be coming to mobile apps over the next few weeks.

The new news Feed settings will now show a list of the top people, Groups and pages that you’ve seen in your News Feed over the past week. Users can choose to sort by pages, people or Groups posts, or see an overall summary of their newsfeed. The filters allow you to unfollow any friend, Group or page if you don’t want to see their stories in your News Feed. Alternatively users can also see who they have unfollowed in the past and re-follow them at anytime.

The new filters allows users to hide specific posts from certain people by clicking on the grey arrow at the corner of the post. Users also get an option to see fewer stories from a particular user, or alternatively stop following them completely. 

Product manager Greg Marra said in a blog post, "Unfollow any friend, Page or Group if you don’t want to see their stories in your News Feed. You can also see who you’ve unfollowed in the past and can choose to re-follow them at anytime."

"If you see a story you’re not interested in or don’t want to see, you can tap the arrow in the top right of that story to hide it. Starting today, when you hide a story you’ll have the option to ask to see less from that person or Page," he added.

Source: Facebook

TomTom Runner Cardio: Fitness Tracker Review

The TomTom Runner Cardio stands out among GPS watches because it has a built-in heart-rate monitor. The watch is a simple device for people who want to track their running workouts. In addition to heart rate, the device measures the distance, time, pace, speed and calories burned while you run, and displays them on a large, easy-to-read screen. It also displays the time of day.

Priced at $269.99 on Amazon, the TomTom Runner Cardio is more expensive than the Adidas miCoach Fit Smart (about $190 on Amazon), which also has a built-in heart-rate monitor. But the miCoach is not recommended for swimming, whereas the TomTom is waterproof to 165 feet (50 m).

Both the TomTom and the miCoach cost more than other GPS watches that can be paired with separate heart-rate monitors, such as the Garmin Forerunner 110 GPS-Enabled Sport Watch with Heart Rate Monitor (about $140 on Amazon), and the Polar RS300x Heart Rate Monitor (about $87 on Amazon). But these less expensive devices require you to wear the monitor on a chest strap, instead of conveniently letting you wear it on your wrist.

I wore the TomTom Runner Cardio several times over the course of a week, to see if the device is really as useful for tracking runs as claimed.   

Design/Comfort:★★★★☆

The Runner Cardio is worn like a watch — it comes in one size and has an adjustable, clip-on rubber strap. The whole thing weighs 2.2 ounces (62 grams) and is about half an inch (1.3 centimeters) thick, but doesn't feel excessively bulky. The strap is about 9 inches (23 cm) long, and could be made to fit snugly even on my relatively slender wrist. It was easy to put on the watch or take it off.

The watch face comes in white and black, and the strap comes in red, black, green and gray. The design is pretty sleek, though its size gives it a somewhat masculine look. The display is about 0.86 by 1 inch (2.2 by 2.5 cm), with a resolution of 144 x 168 pixels. I found it easy to read, and it comes with a backlight for low light or nighttime use. The home screen displays the time of day.

The device has four buttons arranged around the edges of a square that lies right below the display. A button on the side of the display activates the backlight. The battery lasts up to 8 hours with both the GPS and heart-rate tracking functions turned on, or up to 10 hours with GPS only.

The heart-rate monitor can be turned on or off before a workout, but once it's on, it provides heart-rate data in real time. Because the button beneath the display is fairly large, it's easy press it to cycle through your metrics, to see your pace, speed, distance, calories and heart rate while running.

User friendliness: ★★★★☆

Accessing and activating the watch's tracking features was pretty intuitive, so you don't need to spend a lot of time reading a manual. The watch has to acquire a GPS signal before you can start clocking a run, which it did pretty quickly the first time I tried it but took a while the second time.

The device syncs wirelessly via Bluetooth to the MySports smartphone app on your phone, which can be downloaded for free from an app store for iOS or Android. The first time you use the app, you have to link your watch to your MySports account using a computer, which is relatively straightforward.

The app then displays your workouts by date, including the distance and duration of your runs. You can also view each workout to see more info, including calories burned, pace, elevation gain, heart rate and stride, as well as a map of your run. The app will create charts of some of these metrics over time, which could be useful if you are training for an event like a race.

The only real problem I encountered using the Runner Cardio was sometimes having to wait awhile for the watch to acquire a GPS signal before I could start my run. I also noticed that the watch's clock didn't sync to daylight saving time automatically. 

Value of information: ★★★★☆

The ability to measure heart rate, distance and speed in a single wrist-worn device was definitely useful, and even though I'm not a huge fitness buff, I appreciated having all this data because it helped me see my progress over time, and feel a sense of accomplishment.

The app lets you set goals for distance, time and calories, or measure laps or times you want to achieve, and then motivates you to strive for these goals by giving you text reminders about your activity. For example, when I went from running to walking too quickly at the end of my workout, the watch alerted me to my "poor recovery."

You can also use the watch without the GPS feature on a treadmill, but the distance tracking may not be as accurate. (In our review of the TomTom Multi-Sport GPS Watch— a similar model — we found that without GPS, the device reported distance measurements that were as much as 30 percent inflated.)

The Runner Cardio can be used for swimming as well, though I didn't test this feature. 

Enjoyment/Inspiration: ★★★★☆

Overall, I found the device simple and enjoyable to use, and my desire to see my data and improve my progress toward my goals convinced me to go running on a few days when I probably otherwise wouldn't have.

According to TomTom, you can share your workout stats on popular running sites or apps, though the MySports app doesn't seem to have a built-in sharing feature. This wasn't a major issue to me, but people who like to compare workouts might have to download other apps.

Conclusion: 16 out of 20 stars

The pros of the Runner Cardio are that the built-in heart-rate monitor makes tracking your rate easier than wearing a chest strap, and the device's buttons make it very easy to see your stats at a glance. The cons are that the device may not accurately track your distance when the GPS is turned off, and acquiring a GPS signal can take a while. Also, there is no built-in feature for sharing your stats with your friends.

BUY the TomTom Runner Cardio

Ghost Illusion Created in Lab with New Robot

Sometimes, people report having felt a strange, unseen presence around them — and they may attribute it to a ghost. Now, in a new study, scientists describe how the "ghost" is an illusion made by the brain.

In experiments, the researchers were able to trick the participants' brains into creating the eerie sensation.

"The sensation that somebody is nearby when no one is actually present is called 'the feeling of a presence,'" the researchers said. "Although people do not see the 'presence,' they may describe its spatial location and frequently turn around or offer food to the invisible presence."

Apart from being a prominent feature across all cultures, the phenomenon has been described by people with psychiatric and neurological problems, and even in healthy people experiencing physical exhaustion, such as in people doing extreme mountaineering, the researchers said.

In the new study, the researchers created a robot to trigger the ghost illusion in a few dozen healthy people by causing a mismatch in their senses.

"In our first experiment, 30 percent of the healthy participants spontaneously reported the feeling of having somebody behind them, touching them," said Dr. Olaf Blanke, a neurologist at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland.

The robot was made in two parts, and the participants stood in between them — with one part behind them and the other in front of them — wearing blindfolds and headphones. The participants reached out in front of themselves and tapped a button on the robot, triggering the robot behind them to reproduce the participants' arm movements, and touch their backs. This created the illusion that the participants were reaching out in front of them and touching their own backs.

But things got even stranger when the researchers introduced a small delay between participants' actions and the robot's response.

A ghostly experience

The delay between participants' reaching out forward and the sensory signals they received on their backs from the robot touching them caused confusion over the source of their sensation. The brain faced an impossible situation in which the sensory and motor signals didn't match.

The result was an illusory experience, in which the participants perceived the touch as being caused by an invisible presence behind them that was touching their backs. 

"For some, the feeling was even so strong that they asked to stop the experiment," said Giulio Rognini, a neuroscientist at EPFL who led the study, published today (Nov. 6) in the journal Current Biology.

The findings reveal the fine balance between the brain mechanisms that generate the experience of "self" versus "other," and how distorting such mechanisms could lead to strange experiences, the researchers said.

The ghost in the brain

The robot experiment in healthy people is similar to the sensations of some patients with mental disorders, or of healthy individuals under extreme circumstances, Blanke said. "This confirms that [the feeling that a ghost is nearby] is caused by an altered perception of their own bodies in the brain."

To explore the brain basis of this illusion, the researchers looked at the brain lesions of 12 patients who had epilepsy or had suffered a stroke. All of the patients had reported experiences in which they felt a person or a shadow was present, right behind them, or in the corner of their eye.

The researchers linked the illusory ghost perception to lesions in three brain regions: the temporoparietal cortex, the insular cortex and the frontoparietal cortex.

The findings could also help researchers understand the roots of symptoms of schizophrenia, the researchers said. These patients' hallucinatory symptoms, such as hearing alien voices and delusions that they are being controlled, could be triggered by an incorrect of integration of senses in the brain, as previous studies have also noted.

Cyber-Roach! Mic-Equipped Bugs Could Aid Disaster Rescue

Remote-controlled cyborg cockroaches could one day be among the first responders at disaster scenes to help locate survivors.

A team of researchers at North Carolina State University has created a swarm of cyborg cockroaches, nicknamed "biobots," that are equipped with microphones to pick up sounds and trace them to their sources. The researchers hope the biobots could one day be used in disaster-relief situations to locate survivors.

Each cockroach has a tiny circuit board "backpack" attached to it that researchers can use to control the bug's movement. Some of the biobots have a single microphone that can capture sounds at a disaster scene and send them back to personnel. Others have a series of microphones that can pinpoint the source of a sound and then steer the bug toward it.

"The goal is to use the biobots with high-resolution microphones to differentiate between sounds that matter — like people calling for help — and sounds that don't matter — like a leaking pipe," Alder Bozkurt, a professor of electrical and computer engineering at North Carolina State University who worked on the project, said in a statement. "Once we've identified sounds that matter, we can use the biobots equipped with microphone arrays to zero in on where those sounds are coming from."

The researchers have already used the cockroach army to map disaster areas, but are now testing to see if the biobots could help find survivors.

Bozkurt and the team have also developed an invisible "fence" designed to keep the biobots within the boundaries of the disaster site. The fence is made of a series of sensors that redirect the cockroaches when they get too close. It also helps the biobots stick close together so they can maintain wireless communication with each other.

Early tests in the lab went well, the researchers said, but field testing is still needed to see how effective the bugs would be at a real disaster scene.

The idea of turning cockroaches into remote-controlled robots is not new. One company even sells DIY "RoboRoach" kits that enable people to create their own smartphone-controlled cockroaches. The assembler must first glue a backpack circuit board onto the roach's shell and then trim the roach's antennae and stick small electrodes in them that connect to the circuit.

But this kind of technology has stirred up an ethics debate. Allowing people, especially untrained individuals, to attach the backpacks and electrodes to the cockroaches has raised concerns about animal cruelty among some advocates and experts.

But when it comes to navigating disaster scenes, the cyborg roaches do have benefits.

"Insect biobots, with a natural ability to crawl through small spaces, offer unique advantages over traditional synthetic robots," the researchers wrote in a paper detailing the experiment.

The research was presented Nov. 5 at the IEEE Sensors conference in Valencia, Spain.