Month: August 2019

A prisoners dilemma for reallife situations

first_imgThe creation and growth of communities requires a degree of cooperation among citizens. Photo Credit: US National Oceanic and Atmospheric Administration Physicist Matjaž Perc of the University of Maribor in Slovenia has recently developed a model for the evolution of cooperation that provides a more realistic description for the altruistic behavior of individuals than previous explanations do. In a recent issue of the New Journal of Physics, Perc explained how selfish individuals are more likely to cooperate in a prisoner’s dilemma game version which accounts for certain extrinsic factors. For instance, individuals often change their connections, engage in long-distance interaction that bridges gaps, and sometimes experience lesser risk and greater benefit for cooperating than those of the average outcome.”External influences are omnipresent in everyday life,” Perc explained to PhysOrg.com. “So far, the framework of evolutionary game theory, in which the evolution of cooperation is often studied, has not yet been supplemented by external factors. Thus, the payoffs of players (for example, humans, animals, firms, etc.) were considered as being fully deterministic (known in advance). In reality, however, unpredictable expenses, originating, for example, from accidents, fines, small violations of law we didn’t really intend to do can hardly be discarded as being irrelevant. It is interesting to see that under such real-life motivated conditions, cooperation thrives best.”The basic premise of the prisoner’s dilemma is that two suspects are placed in two different rooms, and each is asked separately whether or not his partner is guilty. Prison sentences depend on how each suspect responds: if both remain true to each other, they each serve only six months. If both betray each other, they both serve two years. If one betrays and one stays silent, the silent/cooperative partner serves 10 years while his betrayer goes scot-free. As one of the suspects, if you choose to betray, you will have better results, either serving two years or going free. If you choose to cooperate, you’re in the cooler for either six months or 10 years. With those odds, most people should betray, even though the best result for everyone would be full cooperation. As others have done, Perc studied a version of the prisoner’s dilemma that includes many individuals and repeats the game numerous times, called an iterative prisoner’s dilemma. In contrast with earlier models, however, he did not impose certain restrictions on the players, allowing them to commence or terminate connections, as often happens in real life. Perc also recognized that although outcomes average out “fairly” (e.g. the set prison sentences), sometimes individuals may reap better or worse results at any instance of the game, which he calls random payoff variation. For example, the risk of cooperation is not always equivalent to 10 years behind bars—sometimes, it might be eight, or six, or four. Also, sometimes the single betrayer doesn’t go free, but actually serves more than six months, meaning that two cooperators will benefit more individually as well as overall. Depending on the scale of fluctuations of pre-determined “average payoffs,” it can be rarer for the risk of cooperation to increase, or for the benefits of mutual cooperation to decrease, Perc found. So overall, a certain degree of payoff variations encourages cooperative strategies. Explore further Deceptive behavior may (deceivingly) promote cooperation Citation: A ‘prisoner’s dilemma’ for real-life situations (2006, September 20) retrieved 18 August 2019 from https://phys.org/news/2006-09-prisoner-dilemma-real-life-situations.htmlcenter_img Perc determined critical values for the variable payoffs, as well as for changing and long-term connections, and found that accounting for these two factors—what he calls the “double resonance” phenomenon—results in greater cooperation between individuals. In particular, cooperators survive by forming clusters so as to protect themselves against being exploited by defectors. Cooperators located in the interior of such clusters enjoy the benefits of mutual cooperation and are therefore able to survive despite the constant exploitation by defectors along the cluster boundaries. However, as the temptation to defect exceeds a threshold value, cooperators die out.”In reality, humans often form alliances not just with their immediate neighbours, but also with others that are physically far away,” said Perc. “On the other hand, however, the introduction of shortcuts hinders cluster formation and enables defectors to exploit clustered cooperators not just along the cluster boundaries but also from within. Thus there exists an optimal fraction of shortcuts among players that still enables at least some long-range connections among distant cooperators, but at the same time does not hinder large cluster formation in the spatial domain. In simpler terms, it is good if firms expand, and form alliances with foreign partners, but at the same time they must always maintain a healthy and solid core—a central facility, the Fort Knox, if you will—upon which everything is based and which holds everything together.” Another real-life situation involving the benefits of cooperation is an arms race between two countries that spend billions of dollars on making weapons for fear that their enemy may be investing in the same defensive strategy. Both lose, considering that the money could have been spent on more productive means. According to Perc’s results, countries who can take the risk of forming and trusting allies will aid one another through cooperation. They can more readily cooperate, according to the double resonance phenomenon, by beginning to cooperate during instances of decreased risk, as well as by taking advantage of currently existing long-distance bonds that provide a mechanism for cooperative alliances across the globe.Citation: Perc, Matjaž. “Double resonance in cooperation induced by noise and network variation for an evolutionary prisoner’s dilemma.” New Journal of Physics. 8 (2006) 183.By Lisa Zyga, Copyright 2006 PhysOrg.com What’s best for the individual and what’s best for society are often not the same thing–this predicament is the premise for the famous “prisoner’s dilemma” game. However, healthy societies depend on individuals cooperating for the common good, even at the risk of personal loss. In theory, individuals should choose what’s in their own best self-interest, but the reality is that many people–and even animals–instead choose to cooperate, to the puzzlement of many professionals who study sociology, game theory and other disciplines. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

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Can a formula predict the outcome of a soccer match

first_img“The three key results are (1) the observation of constant team fitness during a season, (2) the derivation of an equation which predicts the average outcome of a match, and (3) the observation that the actual goal distribution can be very well described by a Poisson distribution,” Heuer summarized.Although the researchers’ equation was accurate in many areas, the researchers found that it became less accurate in cases where the goal difference was one or zero. Specifically, in the real data, there were more zeros (ties) than predicted by the equation, and fewer one-goal differences. “The agreement with the actual data is perfect within statistical error if analyzing the goals per team,” Heuer said. “[However,] when analyzing the distribution of goal differences, one observes too many draws. This shows that the assumption of independent Poisson processes is not correct in cases where the goal difference is -1, 0, or 1. This points to interesting psychological effects, favoring a draw.”As the researchers note, there are other random effects that influence goals. These effects include temporary injuries, fatigue, weather conditions that favor one time over another, red cards, and so-called self-affirmative effects – that is, the probability of scoring a goal is increased when a team has already scored one or more goals in that game. Although the influence of these effects is very difficult to predict, the researchers found that these effects have a much smaller overall impact on the final outcome of a match as compared to the typical fitness differences. The analysis also has interesting effects on how we tend to view soccer matches, according to the researchers. For example, the media will often comment that a team that won or lost played particularly good or bad in that match. In contrast, the results here suggest that a team’s fitness level doesn’t change very much from match to match. Yet media reports (and fans) may have a strong tendency to judge a team’s fitness level based too much on the overall score, while ignoring the random effects that may have actually led to the overall score. In addition to predicting the outcomes of soccer matches, the analysis could serve as a framework to classify different types of sports in terms of degree of competitiveness. For example, in sports with many points such as basketball, random effects are probably less pronounced, so that the stronger team has a better chance of winning than in sports with low-scoring games. The first goal is the deepest: Can mathematics predict the match outcome? In their study, A. Heuer, C. Müller, and O. Rubner, all physicists/chemists from the University of Münster in Germany, have analyzed soccer on a statistical level. As the scientists explain, a soccer match is equivalent to two teams throwing dice. Rolling a 6 means “goal,” and the number of attempts of both teams is fixed at the beginning of the match, reflecting each team’s fitness in that season. The higher its level of fitness, the more chances a team has to score a goal.How to determine each team’s fitness level is the main task of the scientists’ analysis. To do this, the researchers analyzed data from all soccer matches in the German Bundesliga between the 1977-’78 season and the 2007-’08 season (except for the 1991-’92 season). In this league, every team plays 34 matches per season. “We attempted to apply typical approaches from the physics community (e.g. analysis of correlation functions, finite-size scaling) to the description of soccer results,” Heuer told PhysOrg.com. “The problem is very similar to the characterization of biased random walks.”Based on the data, the scientists characterized team fitness as the goal difference within a game averaged over a season (in other words, the difference between number of goals scored and allowed by a team). The scientists’ analysis showed that goal difference is an even bigger influence on team fitness than the number of goals. In addition, based on previous results, the home advantage could be taken into account by a team-independent but season-dependent constant. Overall, the researchers found that a team’s fitness level remains constant throughout the season, although it changes between seasons.Using team fitness values, the scientists derived a formula to estimate the expected value of the goal difference in a particular match. The actual number of goals in a match (just like rolling dice) could be described as Poissonian processes; the events occur randomly and, for the most part, independently of each other. Taking all analyzed matches into account, the goal distribution determined in this way agrees almost perfectly with the actual data. Citation: Can a formula predict the outcome of a soccer match? (2010, March 5) retrieved 18 August 2019 from https://phys.org/news/2010-03-formula-outcome-soccer.html More information: A. Heuer, C. Muller, and O. Rubner. “Soccer: Is scoring goals a predictable Poissonian process?” Europhysics Letters, 89 (2010) 38007. Doi:10.1209/0295-5075/89/38007 Explore furthercenter_img This figure compares the calculated goal distribution (green asterisks) with the actual values (open circles). The agreement is good except when the goal difference is -1, 0, or 1. In these cases, the real data shows a larger number of draws, balanced by a fewer number of matches with one goal difference. The disagreement may point to psychological effects that favor a draw. Image credit: A. Heuer, et al. Copyright 2010 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. (PhysOrg.com) — Soccer, like most sports, is a game full of surprises and lucky or unlucky breaks. After all, if it was easy to predict the winner of a soccer match, there wouldn’t be much reason to watch it. But a team of scientists says that soccer is actually a simple match in statistical terms. To demonstrate, they have derived a function that can predict the expected average outcome of a match in terms of the goal difference between the two competing teams. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

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Reeti Its a robot but were not quite sure what it does

first_imgReeti being made by Robopec, which is based in France. The oddity of its aesthetics aside, Reeti is a robot that is designed to act as a kind of media center helper. His main goal is to act as an interface between your PC and your TV. So, if you want to watch a movie in your iTunes library, without being limited to the small screen, a bot like Reeti could help you out. Then again, so could a simple cable, and the cable won’t set you back nearly as much cash. Reeti, when it goes on pre-order on an as yet undetermined date, will cost you about $7000, and that price could still go up. Other than this, no one is exactly sure what Reeti does. Some have speculated that Reeti is, for the time being, mostly a blank platform that developers will be able to write apps for, a kind of like a robot app store, but to be honestly, this business model usually only works on devices that people already want to own for a built in feature, such as cell phones. © 2010 PhysOrg.com This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Reeti: It’s a robot, but we’re not quite sure what it does yet (w/ video) (2011, April 6) retrieved 18 August 2019 from https://phys.org/news/2011-04-reeti-robot-video.html A more stealthy robot may be hearing you soon Explore further More information: www.reeti.fr/en (PhysOrg.com) — Robots come in all shapes and sizes; from sets of blocks, to child sized humans, and then, there is this. At first, this reporter didn’t know exactly how to classify Reeti. It isn’t exactly human, but it isn’t exactly a non-human. The real problem is that face, because humans tend to want to see faces as being human. The ears kind of remind me of Shrek, while the face looks surprisingly like a Snork. I will say this for the little guy (or girl?), it is packing some decent hardware. Each of the robots eyes have a HD camera, so he can see in 3D and recognize objects. It also has a speech synthesizer, that can allow it to read text back to you.last_img read more

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Study finds dogs experience runners high similar to humans

first_img Evolution may explain ‘Runner’s high,’ study says © 2013 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Wired to run: exercise-induced endocannabinoid signaling in humans and cursorial mammals with implications for the ‘runner’s high’ J Exp Biol 215, 1331-1336 jeb.biologists.org/content/215/8/1331.abstractAbstractHumans report a wide range of neurobiological rewards following moderate and intense aerobic activity, popularly referred to as the ‘runner’s high’, which may function to encourage habitual aerobic exercise. Endocannabinoids (eCBs) are endogenous neurotransmitters that appear to play a major role in generating these rewards by activating cannabinoid receptors in brain reward regions during and after exercise. Other species also regularly engage in endurance exercise (cursorial mammals), and as humans share many morphological traits with these taxa, it is possible that exercise-induced eCB signaling motivates habitual high-intensity locomotor behaviors in cursorial mammals. If true, then neurobiological rewards may explain variation in habitual locomotor activity and performance across mammals. We measured circulating eCBs in humans, dogs (a cursorial mammal) and ferrets (a non-cursorial mammal) before and after treadmill exercise to test the hypothesis that neurobiological rewards are linked to high-intensity exercise in cursorial mammals. We show that humans and dogs share significantly increased exercise-induced eCB signaling following high-intensity endurance running. eCB signaling does not significantly increase following low-intensity walking in these taxa, and eCB signaling does not significantly increase in the non-cursorial ferrets following exercise at any intensity. This study provides the first evidence that inter-specific variation in neurotransmitter signaling may explain differences in locomotor behavior among mammals. Thus, a neurobiological reward for endurance exercise may explain why humans and other cursorial mammals habitually engage in aerobic exercise despite the higher associated energy costs and injury risks, and why non-cursorial mammals avoid such locomotor behaviors. (Phys.org) —A team of researchers in the United States has found that dogs appear to gain a “high” from running, similar to the well known “runner’s high” experienced by people who run or jog frequently. In their paper published in The Journal of Experimental Biology, the group describes how they measured neurotransmitter levels in humans, dogs and ferrets as they moved on a treadmill to determine neurobiological reward levels. A yellow labrador retriver dog with pink nose. Credit: Wikipedia.center_img Journal information: Journal of Experimental Biology Explore further Citation: Study finds dogs experience runner’s high similar to humans (2013, May 16) retrieved 18 August 2019 from https://phys.org/news/2013-05-dogs-runner-high-similar-humans.html Most people are aware of the pleasurable feeling known as “runner’s high” some people get from running, either by experiencing it themselves or hearing about it in others. Scientists have found that such sensations are due to the release of neurotransmitters into the bloodstream—one of these neurotransmitter groups, known as endocannabinoids (eCBs) have the same chemical structure as THC, the chemical responsible for the high people get from marijuana. In this new effort, the researchers wanted to know if other animals also experience a runner’s high.To find out, the team enlisted the assistance of some human volunteers, several dogs and some ferrets. Each was put on a treadmill set at a pace fast enough to simulate running. Afterwards blood samples were taken. In analyzing the results, the researchers found elevated levels of eCBs for both the humans and dogs, but not in the ferrets. In another test, the researchers slowed the pace of the treadmill to just a walk for the dogs and humans and found no change in eCB levels.The researchers note that both humans and dogs are part of a group known as cursorial animals—animals that have long legs meant for running. Ferrets on the other hand, are not cursorial, thus they don’t gain any pleasure from running long distances.The researchers theorize that neurobiological rewards are a part of the evolutionary history of animals with long legs meant for running and strong lungs—they helped keep them fit. Running, particularly when not necessary, they suggest, kept such animals in tip-top shape allowing them to escape predators and to hunt efficiently. They noted also that other studies have shown that the fitter a group of primates are, the bigger their brains grow.Based on their results, the researchers suggest, it’s likely other cursorial animals, such as cats, experience a runner’s high as well.last_img read more

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Two independent teams build heat cloaking device

first_img(a) Temperature distribution in a uniform medium connecting a hot (bottom) and a cold region (top). (b) The distribution is distorted in the presence of an obstacle (an air bubble in this example). (c) Adding a thermal cloak restores the transient diffusion and isothermal lines all around the obstacle. (d) Cross section of sample used by Han et al. [1]. (e) Cross section of molded cloak used by Xu et al. [2]. Credit: Physics Viewpoint, DOI: 10.1103/Physics.7.12 More information: 1. Tiancheng Han, Xue Bai, Dongliang Gao, John T. L. Thong, Baowen Li, and Cheng-Wei Qiu, “Experimental Demonstration of a Bilayer Thermal Cloak,” Phys. Rev. Lett. 112, 054302 (2014). dx.doi.org/10.1103/PhysRevLett.112.0543022. Hongyi Xu, Xihang Shi, Fei Gao, Handong Sun, and Baile Zhang, “Ultrathin Three-Dimensional Thermal Cloak,” Phys. Rev. Lett. 112, 054301 (2014). dx.doi.org/10.1103/PhysRevLett.112.054301 Explore further (Phys.org) —Two teams, both in Singapore have created two different types of thermal cloaking devices. In their papers, both published in Physical Review Letters, the teams describe how they went about creating their devices and offer suggestions as to what use they might be put. Researchers create first 3D invisibility cloak Citation: Two independent teams build heat cloaking device (2014, February 10) retrieved 18 August 2019 from https://phys.org/news/2014-02-independent-teams-cloaking-device.htmlcenter_img Cloaking has a become a hot topic in science, and not just because of the popularity of Harry Potter. With the advent of metamaterials, scientists discovered they were able to create devices that bent microwaves—the first cloaking devices. Such devices were followed up by other devices that bent light and infrared radiation and sound—all cloaking devices which worked because of the way metamaterials were able to bend wave based media. In this new effort, the two research teams applied some of the same ideas to heat, which is of course, not a wave media—it moves via diffusion and therefore does not propagate. But, the researchers noted, that doesn’t mean under certain circumstances it too can’t be cloaked.The idea behind cloaking heat is to create an environment where heat diffusion does not occur into an object placed into that environment—instead, like wave cloaking, the heat is caused to stray from its normal path and move around the object instead of into it.The first team created a heat cloak by binding strips of metal and polystyrene together and then placing the result inside of a block made of thermal conducting material. The dimensions of all the materials were adjusted to meet those specified by a mathematical formula based on thickness and conductivity. The arrangement allowed for thermal cloaking of an aluminum cylinder placed inside.The second team created their device by trapping a pocket of air inside a block made of stainless steel—the air pocket was lined with copper. An object placed inside the air pocket was heat cloaked.Neither group has a specific application in mind for their heat cloaking device, but suggest heat cloaking might be useful for managing heat in electronic circuits. One such application might be inside of cell phones as way to prevent batteries from overheating. Both teams note that another result of their work is that they have proven that diffusion cloaking is possible which means it might be applied in other areas, such as with tomography or static currents. © 2014 Phys.org Journal information: Physical Review Letters This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

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Pair of researchers suggest black holes at center of galaxies might instead

first_img Back in 1974, space scientists discovered Sagittarius A* (SgrA ∗)—a bright source of radio waves emanating from what appeared to be near the center of the Milky Way galaxy. Subsequent study of the object led scientists to believe that it was (and is) a black hole—the behavior of stars nearby, for example, suggested it was something massive and extremely dense.What we’re able to see when we look at SgrA∗ are plasma gasses near the event horizon, not the object itself as light cannot escape. That should be true for wormholes too, of course, which have also been theorized to exist by the Theory of General Relativity. Einstein even noted the possibility of their existence. Unfortunately, no one has ever come close to proving the existence of wormholes, which are believed to be channels between different parts of the universe, or even between two universes in multi-universe theories. In their paper, Li and Bambi suggest that there is compelling evidence suggesting that many of the objects we believe to be black holes at the center of galaxies, may in fact be wormholes.Plasma gases orbiting a black hole versus a wormhole should look different to us, the pair suggest, because wormholes should be a lot smaller. Plus, the presence of wormholes would help explain how it is that even new galaxies have what are now believed to be black holes—such large black holes would presumably take a long time to become so large, so how can they exist in a new galaxy? They can’t Li and Bambi conclude, instead those objects are actually wormholes, which theory suggests could spring up in an instant, and would have, following the Big Bang.Making the two’s speculation more exciting is the soon to be installed piece of equipment known as GRAVITY—it will be added to the European Space Observatory in Chili, giving researchers there an unprecedented view of SgrA∗ (and other black holes). In just a couple of years, it should be possible to prove whether Li and Bambi’s idea is correct or not—the photon capture sphere of the wormhole should be much smaller than that for a black hole, they note—if that’s the case with SgrA ∗, space scientists will have to do some serious rethinking of wormholes and how they might fit in to current theories describing the universe. More information: Distinguishing black holes and wormholes with orbiting hot spots, arXiv:1405.1883 [gr-qc] arxiv.org/abs/1405.1883AbstractThe supermassive black hole candidates at the center of every normal galaxy might be wormholes created in the early Universe and connecting either two different regions of our Universe or two different universes in a Multiverse model. Indeed, the origin of these supermassive objects is not well understood, topological non-trivial structures like wormholes are allowed both in general relativity and in alternative theories of gravity, and current observations cannot rule out such a possibility. In a few years, the VLTI instrument GRAVITY will have the capability to image blobs of plasma orbiting near the innermost stable circular orbit of SgrA∗, the supermassive black hole candidate in the Milky Way. The secondary image of a hot spot orbiting around a wormhole is substantially different from the one of a hot spot around a black hole, because the photon capture sphere of the wormhole is much smaller, and its detection could thus test if the center of our Galaxy harbors a wormhole rather then a black hole. Physicist suggests some types of wormholes may stay open long enough to send a photon through © 2014 Phys.org Citation: Pair of researchers suggest black holes at center of galaxies might instead be wormholes (2014, May 30) retrieved 18 August 2019 from https://phys.org/news/2014-05-pair-black-holes-center-galaxies.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.center_img Explore further Journal information: arXiv (Phys.org) —Zilong Li and Cosimo Bambi with Fudan University in Shanghai have come up with a very novel idea—those black holes that are believed to exist at the center of a lot of galaxies, may instead by wormholes. They’ve written a paper, uploaded to the preprint server arXiv, describing their idea and how what they’ve imagined could be proved right (or wrong) by a new instrument soon to be added to an observatory in Chile. Credit: X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScIlast_img read more

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Natural material discovered that exhibits inplane hyperbolicity

first_img Citation: Natural material discovered that exhibits in-plane hyperbolicity (2018, October 25) retrieved 18 August 2019 from https://phys.org/news/2018-10-natural-material-in-plane-hyperbolicity.html More information: Weiliang Ma et al. In-plane anisotropic and ultra-low-loss polaritons in a natural van der Waals crystal, Nature (2018). DOI: 10.1038/s41586-018-0618-9 Thomas G. Folland et al. Precise control of infrared polarization using crystal vibrations, Nature (2018). DOI: 10.1038/d41586-018-07087-5 An international team of researchers has discovered a natural material that exhibits in-plane hyperbolicity. In their paper published in the journal Nature, the group describes their work with molybdenum trioxide and what they found. Thomas Folland and Joshua Caldwell with Vanderbilt University offer a News and Views piece on the work done by the team in the same journal issue. Journal information: Nature Researchers discover directional and long-lived nanolight in a 2-D material Explore furthercenter_img a, Illustration of the orthorhombic lattice structure of layered α-MoO3 (red spheres, oxygen atoms). The orthorhombic structure is based on bilayers of distorted MoO6 octahedra stacked along the [010] direction via vdW interactions. The three possible positions of oxygen atoms are denoted O1–3, and the unit cell is shown dashed. b, Schematic of the unit cell of α-MoO3; the lattice constants are a = 0.396 nm, b = 1.385 nm and c = 0.369 nm. Blue spheres, molybdenum atoms. c, Optical image of α-MoO3 flakes. The α-MoO3 crystals typically appear to be rectangular owing to the anisotropic crystal structure. Labelled arrows indicate crystal directions. Scale bar, 20 µm. d, Raman spectrum taken in the area marked by a red dashed circle in c. Red frequency labels indicate the Raman peaks associated with the lattice vibrations producing the RBs of α-MoO3. Credit: (c) Nature (2018). DOI: 10.1038/s41586-018-0618-9 © 2018 Science X Network As Folland and Caldwell note, hyperbolic materials are those that are extremely reflective to light along one axis and have normal reflectance along another axis. In most such materials, the two axes are not on the same plane. But as Folland and Caldwell further note, a material in which they are in the same plane would be valuable because it could serve as a very thin waveplate—materials that alter the polarization of the light that strikes it. They point out that such a waveplate could allow researchers to manipulate wavelengths at a very small scale. In this new effort, the researchers report the discovery of just such a material—a natural one called molybdenum trioxide.Folland and Caldwell point out that there was a time in the not-too-distant past when it was believed that hyperbolicity only existed in man-made materials. But just four years ago, it was observed in hexagonal boron nitride. It was also determined that the reflective behavior of such materials came about due to vibrations in their crystal lattice, i.e. optical phonons. Such phonons were found to have long lifetimes, which served to prevent the absorption of light. Over the past few years, a number of natural hyperbolic materials have been found.Prior work had shown that molybdenum trioxide was hyperbolic for longwave infrared light. In this new effort, the researchers have shown that it also exhibits in-plane hyperbolicity. They used their finding to confine light in ways that were smaller than its wavelength using hyperbolic phonon polaritons. The lifetimes for the polaritons were found to be approximately 10 times longer than for hexagonal boron nitride.Folland and Caldwell suggest the unique properties of molybdenum trioxide could break new ground in developing nanophotonics. They also note that it has been theorized that hyperbolic materials could be used to create hyper-lenses or heterostructures. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

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The musical roar of joy

first_imgIt’s not a regular affair that one sits back and rejoices the weekend spent. Well, Saturday was one such weekend spent by the people who were present at the World Music Day celebration in the Capital. First, there was music. For us, that’s enough to make us love it! And second, there was ‘good’ music, with the World of Talents group beating their drums till we literally danced. That’s not all, the city – shy, restless, outspoken, quiet, however, danced with the largest flash mob to the tunes of  London Thumakda, Kolaveri Di and so many more tracks! Wait, wait, that’s not it. There were then a line up of excellent bands for all. You can imagine the joy all the music gave to the people as they sat out in the open humid weather, clapping, cheering and hooting for the bands, Turkush, Spice Route and Zephyr. Also Read – ‘Playing Jojo was emotionally exhausting’The Education Tree hosted this spectacular evening of music and dance on the occasion of World Music Day. Aiming to foster and facilitate education, and change the preconceived notions that surround it. They try to promote its objectives by the use of various unique art forms like music, art, dance, theatre and more.The concept of World Music Day was originated in France with an objective to hold free concerts wherein both professional and amateur artists can come together at a common platform to exhibit their talent. Select Citywalk was created into an epicenter of music and gave Delhi its very own musical movement. Also Read – Leslie doing new comedy special with NetflixWhat people loved the most was the amazing interaction by Vivek Vaid, member of World of Talents and the scintillating performance by the band Turkush. Launching their track Kamli, they made the public roar with enjoyment and we all know how it would be when an amazing band plays the songs we listen to on our pods! Spice Route’s Chinmayi’s voice hit just the right chords with the people. By the end, we all hoped World Music Day gets celebrated each day!last_img read more

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Stern action if any link found says Abhishek

first_imgKolkata: Abhishek Banerjee, Trinamool Congress MP and president of the party’s youth wing has categorically said that stern action will be taken against those involved in the murder of Trilochon Mahato in Purulia’s Balarampur if the BJP can prove his party’s involvement of any sort. Banerjee said that his party workers are not involved in the murder of Mahato. “He died due to infighting or it was the sequel to a family feud,” he maintained. Also Read – Heavy rain hits traffic, flightsA tweet of BJP’s national president Amit Shah said: “Deeply hurt by the brutal killing of our young karyakarta, Trilochan Mahato, in Balarampur, West Bengal. A young life full of possibilities was brutally taken under state’s patronage. He was hanged on a tree just because his ideology differed from that of state-sponsored goons.” The body of 18-year-old Mahato was found hanging from a tree a day after the Panchayat election was declared. There was a poster which was found near the tree that read because of his involvement with the BJP at such an early age, he had to pay the price. Trilochan’s father Panu Mahato is a BJP worker as well. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedIt may be mentioned that in a recent interview to a vernacular television channel, Trinamool Congress supremo Mamata Banerjee had said that 13 party workers had been killed by the Opposition. She had said as the Trinamool Congress was confident of its victory then why should the workers take recourse to violence. Abhishek said his party did not believe in violence. “BJP is creating trouble everywhere and then trying to put the blame on the Trinamool Congress.” The police is investing the matter. Partha Chatterjee, TMC secretary general, has also denied the involvement of his party workers in the murder. “We do not believe in the politics of hate and murder. Our workers had been killed but we have never retaliated to take revenge.”In Balarampur, the BJP has bagged two Zila Parishad seats. Out of 17 Gram Panchayat seats, BJP secured 17 while the TMC had got three seats. In Gram Panchayat, out of 92 seats BJP got 70 while the TMC got 22 seats.The Trinamool leaders said BJP had got only 22 seats in 822-member Zilla Parishad in Bengal where elections were held. It bagged 5,747 Gram Panchayat and 752 seats in Panchayat Samity. Under such a situation the BJP is no threat to the TMC and so there was no question of resorting to violence, the TMC leaders said.last_img read more

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Health dept sends notice to pvt hospital over expired registration

first_imgKolkata: The state Health department has issued a notification to Namita Biswas Memorial Eye Hospital in Garia’s Middle Town area, after it failed to renew registration.It has been learnt that the Health department asked the private hospital authorities not to admit patients, after it found some infrastructural lapses in the hospital. The hospital authorities, however, claimed that the Health department has given them verbal consent to continue normal functioning. A senior official of the hospital said that they were asked to stop functioning for two days as the registration was not renewed with the Health department. The hospital authorities, however, urged the health authorities for a relaxation.According to sources, the private eye hospital was running without a valid registration for quite some time. No hospital can operate without a valid registration from the Health department.A question appears here on how a private health establishment could admit patients when it had no valid clearance from the state Health department.last_img read more

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