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A Physicists Guide to Texas Hold Em

first_imgOther connections involve biological evolution. Due to the competitive nature of the game, Sire found similarities with evolutionary models dealing with competing agents. Also, when analyzing the statistical properties of the chip leader (player with the most chips at a given time), Sire found the same phenomenon that occurs in the “leader problem” in evolutionary models. Namely, the average number of chip leaders grows logarithmically (i.e. very slowly) with the number of competing agents, or total number of players. “Physicists are currently studying models of competing agents,” Sire explained. “Possible applications exist in the field of econophysics: markets, options theory in finance, decision making, rumor propagation, etc. Another application I’ve been involved in is evolutionary biology. One devises simplified models of the creation or extinction of species (or new genes). With my colleagues, we have shown that the number of preeminent ‘species’ generically grow with the total number of species, and that this result should hold in many contexts (for instance, the number of leaders of the Fortune 500).”A third connection involves extreme value statistics, a physics branch that analyzes the probability of the occurrence of extreme events. In Sire’s model, some of the properties of the chip leader also display extreme value statistics: the probability that the chip leader holds a given stack is universal (and given by the well-known Gumbel distribution in physics.) “Let us consider a random signal: for example, the stock of IBM, or the daily temperature in New York,” Sire explains. “Now let us look at its maximum in a one-month period. This is itself a random variable. If the initial random signal is only weakly correlated in time, the probability distribution of the (monthly) maximum of the signal takes a universal form which is independent of the precise nature of the considered signal! Recently, physicists have been interested in the maximum of strongly correlated variables, which can now take any form.”As for finding the best strategies, Sire’s model doesn’t determine optimal playing decisions, other than general hints from observations, For example, the advice that “a player should be careful when playing bad hands if many players have already bet” is totally irrelevant, according to the model, as far as the global evolution of the tournament is concerned. However, the model predicts that there exists an optimal probability to go all-in (to bet all one’s chips).Sire notes that two famous mathematicians (e.g. Emile Borel and John von Neumann) have looked for optimal strategies in head-to-head poker, but prediction for tables with ten players including all-in events still presents a formidable task. More information: Citation: Sire, Clément. “Universal statistical properties of poker tournaments.” To be published. (Currently at arxiv.org/abs/physics/0703122)For more information, see Clément Sire’s Web page: www.lpt.ups-tlse.fr/clement “In this Letter, we study a very human and futile activity: poker tournaments,” Sire writes in his paper, submitted to an APS Physical Review journal. His model quantifies the evolution of Texas hold ‘em tournaments, based on aspects such as the distribution of chips, the number of surviving players over time, etc. Overall, his results closely mirror those observed in real-life online tournaments.“While human laws (such as bluff, prudence and aggressiveness) determine much of the individual outcomes of poker tournaments, these tournaments are ideal for statistical analysis because they are isolated systems—they don’t depend on outside factors,” Sire explained to PhysOrg.com. While Sire’s model provides an accurate description of poker tournaments, the model also shares similar characteristics with other seemingly unrelated areas. For example, the physical model of persistence tells the probability that some random process never falls below a certain level. Or, in poker talk, the persistence model describes the number of surviving players (those that have not lost all their chips). As Sire explains, the “decay rate” of players (as they lose their chips) is exactly the same as the (exponential) growth rate of the blind bets, which are bets that start off the pot of money at the beginning of every game and are therefore also the minimal bets. This also means that the growth rate of the blind bets entirely controls the pace of a tournament, which in practice allows the organizers of a tournament to control its duration. The model shows that the total duration of a tournament grows only logarithmically (i.e. very slowly) with the initial number of players, which explains why the wide range of real tournament sizes (100-10,000 players) remains manageable. “The model can also help poker players to evaluate their current ranking in a poker tournament,” Sire said. “For instance, if a player owns twice the average stack, he is currently in the top 90%. If his holding is only half of the average stack, he only precedes 25% of the other players.“Consider a temporal random signal [such as the graph of a company’s stock]. Its persistence is the probability that it never goes below (or above) a given threshold,” Sire explains. “With my colleague Satya Majumdar, we have devised several ways to compute this quantity in various contexts, which decays exponentially fast, or as a power-law. Persistence has been measured in many physical systems, and has obvious applications outside physics: for example, what is the probability that Google’s stock remains above $450 for the next year (certainly high, I admit)?” (PhysOrg.com) — What are the odds that poker can be explained by statistical physics, much the same as a variety of other complex systems? They’re pretty good, according to physicist Clément Sire of Université of Toulouse and CNRS in France, who demonstrates in a recent paper that many of the statistical properties of poker tournaments are universal. Sire’s model makes connections between poker and evolution, extreme value statistics and the physical model of persistence. Copyright 2007 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. Citation: A Physicist’s Guide to Texas Hold ‘Em (2007, April 4) retrieved 18 August 2019 from https://phys.org/news/2007-04-physicist-texas-em.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.last_img read more

Sharp Unveils SolarPowered TV

first_imgSharp´s 26-inch low-power TV prototype paired with a solar module. Explore further The TV uses about one-fourth the power and has about one-third the annual energy consumption of a conventional CRT TV with the same screen size. Compared to today´s LCD TVs, the low-power prototype uses about one-third the power, and about one-half the annual energy consumption. This extremely low power consumption allows the TV to be powered from one of Sharp´s triple-junction thin-film solar cell modules, with a surface area of about the same size as the LCD screen. The company plans to market the TV and solar energy system as a combination pair.The technology could bring TV to the 1.6 billion people worldwide who live off the grid, improving their lives not just with entertainment, but also access to news and information. The company predicts that environmentally-conscious consumers would also be interested in such a product.Besides the low-power TV prototype, Sharp will also exhibit other energy-saving technologies at the G8 Summit, including a 57-inch AQUOS TV, a solar-LED lighting module, and a super-thin (20-mm) 65-inch LCD TV that uses about half the annual energy consumption of conventional LCD TVs. In addition, the company will display a semi-transparent “see-through” solar cell module. Developed with a laser-trimming process to create large numbers of optically transparent slits over the surface of the cell, the modules could be used as architectural elements, such as in skylights and curtain walls.via: Sharp and Engadget For the 1.6 billion people living in areas without utility-supplied electricity, Sharp has designed a TV that can get 100% of its power from the sun. The company plans to exhibit the 26-inch LCD prototype at the Hokkaido Toyako Summit, or G8 Summit, in Hokkaido, Japan, on July 7-9. Intel buzz is all about display on power diet, battery life boost Citation: Sharp Unveils Solar-Powered TV (2008, July 4) retrieved 18 August 2019 from https://phys.org/news/2008-07-sharp-unveils-solar-powered-tv.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.last_img read more

Space Robot Can Autonomously Reconfigure Itself

first_img Citation: Space Robot Can Autonomously Reconfigure Itself (2009, June 15) retrieved 18 August 2019 from https://phys.org/news/2009-06-space-robot-autonomously-reconfigure.html The robot that climbs in the pipe As Farhad Aghili of the Canadian Space Agency in Saint-Hubert, Quebec, and Kourosh Parsa of ESAB Cutting Systems in Florence, South Carolina, explain in a recent study, most conventional reconfigurable robots have a modular design. Although modular robots can change their size and shape, they require complex joints for connecting modules, as well as a docking system for exchanging modules. Aghili and Parsa’s new design for a reconfigurable robot does away with modules, and instead uses passive joints that allow the arms to twist and change their length, depending on the task at hand. The cylindrical passive joints, i.e., joints that don’t use actuators or sensors, lie in between cylindrical telescopic arms. As the joints twist and turn and the telescopic arms extend or shrink, the robot looks a bit like one of Inspector Gadget’s bionic arms, but precisely controlled.In order to reconfigure itself, the engineers explain that the robot must constrain the motion of the end of its arm in order to control its joint parameters. The robot can do this in several ways, such as when the arm grasps a fixed point or when two robot arms grasp the same object. In either case, the robot forms a closed chain. At this point, one or more of the brake mechanisms on the passive joints can be released by activating a solenoid, which allows the “elbows” of the robot to twist and lengthen or shorten its arms. When the system achieves its desired configuration, the joint brakes are locked, and the robot detaches itself from its constraining object.The new “lockable joint” design offers several advantages compared with the conventional modular design of reconfigurable robots. The main advantage is simplicity, with the new design being compact and weighing less, which is important for launch considerations. The new design also enables the robot to autonomously reconfigure itself, since links and joints don’t need to be detached and reattached as in the modular design. “In a nutshell, this work establishes a new concept of a reconfigurable robot with supporting mathematical analysis and control method,” Aghili told PhysOrg.com. “The conditions on the manipulator constraints and the passive joints to make it possible that the robot changes its current configuration to a desired one are derived. The control system then autonomously realizes the configuration change while demanding minimum actuation effort. Autonomous calibration of the manipulator after every configuration change is another significant aspect of this work.”This kind of reconfigurable robot could have many uses in space, including performing inspections, assembling devices, and carrying objects. Aghili added that a reconfigurable robot like this one could also have applications in mining, nuclear power plants and the military. He noted that a team of students from McGill University has built a preliminarily prototype of a similar reconfigurable robot.“The Space Shuttle manipulator has been served in numerous space missions for more than two decades,” he said. “However, the Shuttle is scheduled to be soon retired and the next generation of NASA spacecraft will not have a large cargo bay, such as the Shuttle’s, to accommodate a manipulator with long booms. In this retrospect, a reconfigurable robot with telescopic joints, which can be contained in a small volume that is suitable for launch, is seriously considered for the next generation of spacecraft manipulators.”More information: Farhad Aghili and Kourosh Parsa. “A Reconfigurable Robot with Lockable Cylindrical Joints.” IEEE Transactions on Robotics. To be published.Copyright 2009 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. By connecting their endpoints, two reconfigurable robots autonomously change their configurations by altering the lengths of their arms and twisting their joints. Image credit: Aghili and Parsa. ©2009 IEEE. A robot designed to work in space should ideally be a Jack of all trades, with the ability to perform a wide variety of tasks by itself. By having one robot that can handle many jobs, astronauts can cut down on weight in order to reduce launch cost. As presented in a recent study, a new type of reconfigurable robot can perform diverse tasks by changing its configuration, such as lengthening and twisting its “arms,” in a much simpler and more compact way than previous reconfigurable robots. Explore further 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

300 mph New Land Speed Record for a Hydrogen Powered Vehicle

first_imgImage source: Ray the Rat via blog.buckeyebullet.com Citation: 300 mph: New Land Speed Record for a Hydrogen Powered Vehicle (2009, September 28) retrieved 18 August 2019 from https://phys.org/news/2009-09-mph-hydrogen-powered-vehicle.html The speed test took place at the Bonneville Speedway at the Bonneville Salt Flats in Utah. This is a location often used to test land speeds. This car is the first hydrogen powered fuel cell vehicle to break the 300 mph mark. (Note: The streamliner that Jesse James used to make land speed history did not go the entire distance of the Flying Kilometer event. And it didn’t break 200 mph.) In order to receive a certification of a record, a vehicle must sustain speeds for more than a mile, two times within an hour. The Buckeye Bullet 2 managed this feat.Ohio State University is no stranger to setting land speed records with alternative energy vehicles. OSU’s original Buckeye Bullet set the record as the first electric vehicle to go 300 mph. Of course, there is a difference between building a car for speed, and building one that provides sustained speed and power over a longer distance. The good news, though, is that commuter cars don’t need to go 300 mph. The fact that it is possible could lead to more interest in all-electric and hydrogen-fueled vehicles in the future.© 2009 PhysOrg.com (PhysOrg.com) — One of the complaints that many have with regard to vehicles powered by alternative energy is the fact that they don’t really have a lot of speed. However, this does not necessarily have to be the case. Last week, a group of engineering students set a land speed record for a vehicle powered by hydrogen fuels cells. The car that was able to break 300 mph is the Buckeye Bullet 2. 80-mph electric car to go on sale this summer in the US 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. Explore furtherlast_img read more

Genome Engineering Could Provide New Method of Creating Diesel

first_img New biofuel from trees developed at UGA Joule Biotechnologies, Inc. has announced that it has used a process of genome engineering to create organisms that can turn carbon dioxide into hydrocarbons that can be used as fuel. The process will be powered by the sun. Joule is planning to create a viable diesel production process using light and air. In a press release from Joule, the basics of the process are explained:Joule is advancing a new, photosynthesis-driven approach to producing renewable fuels, avoiding the economic and environmental burden of multi-step, cellulosic or algal biomass-derived methods. The company employs a novel SolarConverter system, together with proprietary, product-specific organisms and state-of-the-art process design, to harness the power of sunlight while consuming waste CO2. Its pioneering technology platform has already been proven out with the conversion of CO2 into ethanol at high productivities, a process that enters pilot development in early 2010. With this latest feat of genome engineering, Joule is now capable of directly producing hydrocarbons – setting the stage for delivery of infrastructure-compatible diesel fuel without the need for raw material feedstocks or complex refining.The breakthrough was made possible by the discovery of unique genes coding for enzymatic mechanisms that enable the direct synthesis of both alkane and olefin molecules – the chemical composition of diesel. Production was achieved at lab scale, with pilot development slated for early 2011.Joule is hoping that its process will help reduce dependence on other sources of diesel, fostering better energy independence. The organisms that Joule is engineering are capable of directly secreting hyrdocoarbon molecules. Joule points out that it will be using non-arable land, as the process will not need to grow crops. No fresh water will be needed, either.The idea of creating diesel using light and air (and a few other components) is an interesting concept if Joule can make it work, and one that could help reduce reliance on oil for diesel fuel, as well as reducing overall carbon emissions present in the diesel fuel production process.© 2009 PhysOrg.com When we think of genetic engineering, our minds often jump to giant tomatoes and animal cloning. However, this is not always the case. 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. Diesel fuel. Image credit: Shizhao via Wikimedia Commons Citation: Genome Engineering Could Provide New Method of Creating Diesel (2009, November 16) retrieved 18 August 2019 from https://phys.org/news/2009-11-genome-method-diesel.html Explore furtherlast_img read more

Scientists finally determine iceman Otzis last meal

first_imgOtzi the Iceman, a well-preserved natural mummy of a Chalcolithic (Copper Age) man from about 3300 BC, who was found in 1991 in the Schnalstal glacier in the Ötztal Alps, near Hauslabjoch on the border between Austria and Italy. © South Tyrol Museum of Archaeology (PhysOrg.com) — In a presentation at the Seventh World Congress on Mummy Studies, researchers from the Institute for Mummies and the Iceman revealed that they had finally located the iceman known as Otzi’s stomach and determined his last meal. They were also able to successfully sequence his entire genome. Researchers from the Institute for Mummies and the Iceman in Italy divided the presentation into three different topics. The first part of the presentation was given by microbiologist Frank Maixner. He had recently examined old tomography scans taken of Otzi back in 2005 and was able to finally locate the stomach which was farther up in the torso and in an unusual position. They found the stomach to be full and, upon examination and sequencing of the DNA, they determined that Otzi had eaten Alpine ibex just 30 to 120 minutes before his death.The next presentation was led by anatomist Frank Ruhli and dentist Roger Seiler from the Centre for Evolutionary Medicine through the University of Zurich. They presented the dental health of Otzi who was presumed to have dies between the age of 35 and 40. Using three-dimensional images of his teeth, they showed how Otzi had suffered some form of blunt force trauma to two teeth only a few days before his death. They also showed how he suffered from periodontal disease and many cavities. These signs of cavities confirm the fact that the Iceman had consumed a diet full of carbohydrates.The final part of the presentation was led by geneticist Angela Graefen from the Institute for Mummies and the Iceman. She reported that her team had finally succeeded in sequencing Otzi’s full genome. This genome has already shed some light on some previous beliefs. While most artists performing facial reconstructions of Otzi have shown him with blue eyes, the new sequenced genome show that he probably had brown eyes. Iceman’s new model on display at Bolzano museum Explore furthercenter_img © 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: Scientists finally determine iceman Otzi’s last meal (2011, June 22) retrieved 18 August 2019 from https://phys.org/news/2011-06-scientists-iceman-otzi-meal.htmllast_img read more

Sodiumion battery cathode has highest energy density to date

first_img Explore further This Ragone plot for the new cathode material (red circles) and other cathode materials for Na-ion batteries shows that the new cathode has the highest energy density for a wide range of charge and discharge rates. Credit: Park, et al. ©2013 American Chemical Society More information: Young-Uk Park, et al. “A New High-Energy Cathode for a Na-Ion Battery with Ultrahigh Stability.” Journal of the American Chemical Society. DOI: 10.1021/ja406016 The researchers, Young-Uk Park, et al., from Seoul National University and KAIST, both in South Korea, have published their paper on the new high-energy cathode in a recent issue of the Journal of the American Chemical Society. As the researchers explain, Na-ion batteries have the potential to meet and even exceed the performance of today’s Li-ion batteries. “The fascinating thing is that Na chemistry is much richer and has more variety than that of Li,” coauthor Kisuk Kang, Professor of Materials Science and Engineering at Seoul National University, told Phys.org. “This makes us believe that there will be unexplored Na battery electrodes out there that can far excel the current Li batteries.”Both Na-ion and Li-ion batteries are candidates for being part of a large-scale system that stores energy generated by new technologies, such as solar, wind, and geothermal technology, where energy is produced intermittently. Although Li-ion batteries’ high energy densities enable them to store a large amount of energy in a small space, the downsides of these batteries are their high cost and low stability. Since sodium is abundant in the earth, it is much cheaper than lithium, even though Na-ion batteries face their own challenges.One of these challenges is a low energy density. Until now, the highest energy density of a Na-ion battery has been about 520 WH kg-1. The root of this problem can be traced to the inherent characteristics of sodium (in particular, a less negative redox potential compared to lithium), which reduces the operating voltage and leads to the lower energy density. Another major challenge for Na-ion batteries is that, even moreso than Li-ion batteries, they suffer from poor long-term stability. This problem also stems from an inherent characteristic of sodium, which is that sodium ions (1.02 Å) are nearly twice as large as lithium ions (0.59 Å). The large size causes a greater change in the host structure upon insertion and removal, which results in a decrease in capacity after repeated cycles.The new cathode material improves in both areas. The researchers attribute the 600 Wh kg-1 energy density to the cathode material’s open crystal framework with vanadium redox couples, which leads to a high voltage that in turn increases the energy density. The new cathode material also allows the Na-ion battery to retain 95% of its capacity over 100 cycles and 84% for 500 cycles. This outstanding cycle life arises from the fact that the cathode material has the smallest volume change among Na cathodes so far, which is due to the rigid framework that is less sensitive to Na ion insertion and extraction compared to other frameworks.In the future, the researchers plan to further improve the electrochemical properties of this Na-ion battery cathode with the goal of designing next-generation Na-ion batteries for new applications.”Further improvements in the cycle stability need to be accomplished in order to be considered for large-scale systems because it requires exceptionally long cycle life (>10 years), unlike small electronic devices,” Kang said. “In this respect, not only the electrode stability, but also other aspects such as the compatibility between electrode and the electrolyte, and the electrolyte stability itself, have to be simultaneously considered.”The researchers plan to address these challenges when designing future electrodes.”We are currently searching for more new electrode materials that can outperform the material that was reported this time,” Kang said. “We have both computational and experimental tools to search for them, which will accelerate the identification of this new material.” Sodium-air battery offers rechargeable advantages compared to Li-air batteries 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 (Phys.org) —Although sodium-ion (Na-ion) batteries don’t perform as well as lithium-ion (Li-ion) batteries, they have the potential to be a cheaper alternative. In a new study, scientists have designed a new cathode for Na-ion batteries that provides an energy density of 600 Wh kg-1, which is the highest reported so far for Na-ion batteries and even rivals the energy densities of some Li-ion batteries. The new cathode material also has a greatly improved cycle life, bringing Na-ion batteries a step closer to realization as part of a large-scale energy storage system. Citation: Sodium-ion battery cathode has highest energy density to date (2013, September 12) retrieved 18 August 2019 from https://phys.org/news/2013-09-sodium-ion-battery-cathode-highest-energy.html Journal information: Journal of the American Chemical Society © 2013 Phys.org. All rights reserved.last_img read more

Trio create model to explain massive heat in the Suns corona

first_img(Phys.org)—A trio of researchers, two with Ecole Polytechnique and the other with Université Paris, all in France, has created a computer model that is meant to show how it is that so much heat is in the sun’s corona. In their paper published in the journal Nature, Tahar Amari, Jean-François Luciani and Jean-Jacques Aly describe their model, how it came about and why they think it is accurate. Emissions from various layers of the solar atmosphere, using data from the NASA Iris mission. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique. FRANCE Citation: Trio create model to explain massive heat in the Sun’s corona (2015, June 11) retrieved 18 August 2019 from https://phys.org/news/2015-06-trio-massive-sun-corona.html Exploring the solar magnetic Mangrove and below . This movie shows an observer (author) looking at and exploring the solar magnetic Mangrove , and diving below the surface of the Sun. This movie was created using the CAVE virtual reality system of TechViz (Paris). Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique.FRANCE The trio point to other observable phenomena that help bolster the credence of their theory—the fact that the temperature of the corona does not vary much over the course of sunspot cycles, for example, which they say is because the sun’s magnetic field is not sensitive to it, because they are deeply rooted in the sun—their model describes shallow activity. Also, they note that other researchers have found evidence of solar tornadoes, which in a way are similar to the trees describe by the model and which can also transport heat up and off the surface. And finally, other observations have revealed that spectral lines of some elements are split into multiple components on the surface, which they team suggests would occur if there happened to be a magnetic field like the one they use in their model.More research will have to be conducted both by the research team and others, of course, to see if the model will continue to hold up under scrutiny. 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: Small-scale dynamo magnetism as the driver for heating the solar atmosphere, Nature 522, 188–191 (11 June 2015) DOI: 10.1038/nature14478AbstractThe long-standing problem of how the solar atmosphere is heated has been addressed by many theoretical studies, which have stressed the relevance of two specific mechanisms, involving magnetic reconnection and waves, as well as the necessity of treating the chromosphere and corona together. But a fully consistent model has not yet been constructed and debate continues, in particular about the possibility of coronal plasma being heated by energetic phenomena observed in the chromosphere. Here we report modelling of the heating of the quiet Sun, in which magnetic fields are generated by a subphotospheric fluid dynamo intrinsically connected to granulation. We find that the fields expand into the chromosphere, where plasma is heated at the rate required to match observations (4,500 watts per square metre) by small-scale eruptions that release magnetic energy and drive sonic motions. Some energetic eruptions can even reach heights of 10 million metres above the surface of the Sun, thereby affecting the very low corona. Extending the model by also taking into account the vertical weak network magnetic field allows for the existence of a mechanism able to heat the corona above, while leaving unchanged the physics of chromospheric eruptions. Such a mechanism rests on the eventual dissipation of Alfvén waves generated inside the chromosphere and that carry upwards the required energy flux of 300 watts per square metre. The model shows a topologically complex magnetic field of 160 gauss on the Sun’s surface, agreeing with inferences obtained from spectropolarimetric observations, chromospheric features (contributing only weakly to the coronal heating) that can be identified with observed spicules and blinkers, and vortices that may be possibly associated with observed solar tornadoes8. Explore further Emissions from various layers of the solar atmosphere, using data from the NASA Iris mission. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique. FRANCE © 2015 Phys.orgcenter_img SOHO and Hinode offer new insight into solar eruptions Model of the complex magnetic field on the Sun’s surface, resembling the roots and branches of mangroves, rooted in the boiling Sun. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique.FRANCE Solar disk image taken in 2011 with large scale atmosphere during as visible during an eclipse in 2008. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique.FRANCE & Eclipse S.Habbal and M. DruckMuller. This movie shows the heating obtained by the model at the heart of the discovery. The model allows a closer look at high resolution of Sun horizon. The boiling pan of plasma just underneath the surface of the Sun, generates and feed the magnetic field that emerges above and create the magnetic Mangrove, whose roots dance like flames as they are heated. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique.FRANCE. Model of the complex magnetic field on the Sun’s surface, resembling the roots and branches of mangroves, rooted in the boiling Sun. Credit: Tahar Amari /Centre de physique théorique.CNRS-Ecole Polytechnique.FRANCE For some time space scientists have been perplexed by research results that show the sun’s corona is millions of degrees hotter than its surface. In this new effort, the researchers built a model that describes how that might occur and then offer some evidence to back up their claims.Scientists know that on the sun’s surface, rotating areas of gas create what are known as dynamos—where plasma causes charges to come about. In their model, the researchers suggest that when such dynamos “dump” their energy, it causes small eruptions to come about on the surface, allowing energy to dissipate out to the corona. The team describes their model as resembling a mangrove forest. The roots of the trees represent surface magnetic fields—energy makes its way up the trees and dissipates near the top like oxygen from tree leaves into the atmosphere, and that is how the energy reaches the corona. Journal information: Naturelast_img read more

New measurement with deuterium nucleus confirms proton radius puzzle is real

first_imgA large team made up of researchers from across the globe has repeated experiments conducted several years ago that showed a different radius for a proton when it was orbited by a muon as opposed to an electron—a finding dubbed the proton radius puzzle—using a deuterium nucleus this time and has found the same puzzle. In their paper published in the journal Science, the team describes the experiments they conducted, what they found and offer a few possible ideas to help dispel the notion that the puzzle indicates that there may be some problems with the Standard Model. Explore further More information: R. Pohl et al, Laser spectroscopy of muonic deuterium, Science (2016). DOI: 10.1126/science.aaf2468AbstractThe deuteron is the simplest compound nucleus, composed of one proton and one neutron. Deuteron properties such as the root-mean-square charge radius rd and the polarizability serve as important benchmarks for understanding the nuclear forces and structure. Muonic deuterium μd is the exotic atom formed by a deuteron and a negative muon μ–. We measured three 2S-2P transitions in μd and obtain rd = 2.12562(78) fm, which is 2.7 times more accurate but 7.5σ smaller than the CODATA-2010 value rd = 2.1424(21) fm. The μd value is also 3.5σ smaller than the rd value from electronic deuterium spectroscopy. The smaller rd, when combined with the electronic isotope shift, yields a “small” proton radius rp, similar to the one from muonic hydrogen, amplifying the proton radius puzzle.Press release © 2016 Phys.org Citation: New measurement with deuterium nucleus confirms proton radius puzzle is real (2016, August 12) retrieved 18 August 2019 from https://phys.org/news/2016-08-deuterium-nucleus-proton-radius-puzzle.html Scientists have been able to calculate the radius of a proton (0.88 ± 0.01 femtometers) for some time using the charge of the electron that orbits around it and doing so has helped confirm theories regarding the Standard Model. But, in trying to improve the accuracy of the measurement by using a negatively charged muon (which orbits closer to the proton), researchers at the Max Planck Institute back in 2010 found a different radius—one that was 7 deviations from what was considered the official value. This proton radius puzzle has had physicists scratching their heads ever since because it suggests there is an error in the Standard Model somewhere. Over the past six years various researchers have offered theories to solve the puzzle, most of which have involved ways to preserve the Standard Model, but to date, the puzzle still remains.In this latest effort the researchers sought to gain more insight into the problem by adding another piece to the puzzle, a neutron, i.e. by using a deuterium nucleus. Their thinking was that the presence of the neutron would change the way that electrons and muons perceived the proton charge. They report that they found that the measurement they made of the radius of the proton was still different from that found with just an electron and proton, by approximately 7.5 sigma.The results by the team offer no new explanations for the measurement discrepancies—it remains a puzzle, but they do offer some possible avenues for further investigation, e.g. ways to improve measurements and forcing muons to interact with the protons to see if there might be any evidence of an unknown force at work.center_img The quark structure of the proton. There are two up quarks in it and one down quark. The strong force is mediated by gluons (wavey). The strong force has three types of charges, the so-called red, green and the blue. Note that the choice of green for the down quark is arbitrary; the “color charge” is thought of as circulating among the three quarks. Credit: Arpad Horvath/Wikipedia Journal information: Science Proton radius puzzle may be solved by quantum gravity 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

Sufis around the world on Capital stage

first_imgIn a world torn between religion and humanity, an appeal for peaceful initiative becomes mandatory  and obligatory. On similar sidelines of how culture should ideally preceed religion is the motto of the Sufi festival organised by Indian Council of Cultural Relations (ICCR). It aimed to establish the non-religious nature of Sufi traditions.‘ICCR’s support to the International Sufi Festival is in continuation of its support last year with firm conviction that Sufi tenets have originated even before the advent of Islam with their roots in Gypsy traditions and have been closer to nature without influence from any narrow beliefs,’ said Suresh K Goel, Director General, ICCR. Also Read – ‘Playing Jojo was emotionally exhausting’The participating groups in the festival like the Sidhi Goma group from Gujarat has its origins in the vibrant rhythms of Africa while the Baul music of Bengal finds resonance in nomadic traditions with Hinduism at its centre. The group from Spain whose music is based on flamenco, gives expression to passion for life itself without linkage to any religion.‘This year the festival had participation from six countries — Spain, Russia, Iran, Tunisia, Azerbaijan and India,’ added Goel. Also Read – Leslie doing new comedy special with NetflixThe performances by all participating groups from across the world enthralled the general audience and Sufi music lovers equally. The Iranian music troupe  compiled the ghazals of their land with artists Sahar Lotfi and Maryam Gharasou. Similarly Russian folk music was a mix and match of humorous rhymes, ritual and lyrical songs. The band, Otava Yo sang and dedicated their renditions to Russian epical heroes, defenders of the motherland and characters from Russian legends. The music of Spain focussed on its biggest USP — the flamenco. Curro and Carlos Pinana along with their rythmic guitar and soulful voice mesmerised the audience.Finally the Indian touch was lent by Bauls and Fakirs of Bengal who sang about love, devotion and humanity.  The artistes believes that all men irrespective of religion, caste and creed are equal, which reflected in their music throughout.last_img read more