Citation: Is dark matter made of axions? (2008, March 3) retrieved 18 August 2019 from https://phys.org/news/2008-03-dark-axions.html Explore further Tevatron experiments report latest results in search for Higgs boson Aaron Chou and William Wester run their Fermilab experiment looking for axions. Photo Credit: Femilab 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. Wester, a scientist at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, worked closely with Aaron Chou, now at New York University, and a group of scientists from Fermilab and the University of Michigan in Ann Arbor, to design an experiment to test the existence of axion-like particles within a certain range. Their results can be found in Physical Review Letters: “Search for Axionlike Particles Using a Variable-Baseline Photon-Regeneration Technique.”Axions are hypothetical particles that have a small mass in the milli-electronvolt (eV) range, making them 500 million times lighter than an electron. Additionally, an axion should have no spin. “Normally,” Chou points out, “we can only detect these kinds of particles with telescopes, looking out into space. And then it is only an indirect detection.” The idea was to create conditions allowing them to detect particles in the milli-eV range during a lab experiment.“For particles that interact strongly enough for us to detect, there are constraints on where they could exist or not,” Chou continues. “For the specific region of our experiment, no one would have thought to look into it without the PVLAS experiment.”Wester explains that the PVLAS collaboration did an experiment in which a signal that could have been an axion was detected. “We wanted to see if we could get the same results,” he says. The PVLAS experimenters eventually ruled out the signal after Wester and Chou started to work with their peers on this experiment. However, there were still some innovations that encouraged the Fermilab group to move forward.“We set things up a little differently,” Wester says. He points out that the Tevatron magnets used in the Fermilab experiment were stronger and better suited for experiments in the milli-eV range than those used in previous experiments. With the magnetic field in place, a laser was aimed down the middle. A “wall” was placed in the middle of the magnetic field as well. The magnetic field would possibly change some of the photons from the laser into axions. The wall would stop the photons, but the axions would emerge on the other side. “There were four different configurations,” Wester continues. “We also had the blocking mechanism placed off to the side to change the effective length of the magnetic field. We also did it with two different polarizations, vertical and horizontal.”Wester says that, unfortunately, the experiment found “no evidence of new particles.” But, he insists, “It turns out we’re able to exclude any possible particle of this type a little more stringently. It extended the region to be excluded.”Chou thinks that maybe, with a stronger magnetic field, it might be worth re-exploring this region. “The effect we are looking for gets stronger as the magnetic field does.”Both scientists are interested in the future possibilities. “There is a proposal out there that involves putting very precisely controlled optical cavities before and after the wall, and using stronger and longer magnets,” Wester explains.Chou also points out that the data from the Fermilab experiment is still being examined. “There is speculation about particles called chameleons, which take on the properties of their environments.” These chameleon particles would have a small mass in low energy density, and large mass in environments of high energy density. “We are continuing analysis to see if maybe we can find a chameleon particle.”In the search for dark matter particles, Wester is optimistic about the role he and his colleagues are playing. “We did a serious measurement and excluded a region,” he says. “If our small experiment helps heighten awareness and leads to more experimental efforts, even using other techniques as well, it will be a huge benefit that we have done this.”Find out more about the Fermi Lab experiment by visiting gammev.fnal.gov .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. One of the mysteries of our universe is that of dark energy and matter. Scientists all over the world are attempting to discover what particles make up dark energy and matter. “Axions are one of the particles considered for dark matter,” William Wester tells PhysOrg.com. “We were hoping to get a signal proving that they exist with this experiment.”
(PhysOrg.com) — In key advances for the field of superconductivity, a research group has created versions of a class of widely studied superconducting compounds that are each one continuous crystal, rather than composed of many crystalline grains. These single-crystal materials are important achievements because they display better properties than polycrystalline types and are easier to study. In a series of four recent papers, three published in Physical Review B and one in Physical Review Letters, the researchers describe the process they developed to “grow” the single-crystal materials. They also lay out the basic but vital measurements they performed on them, including their molecular structures and how they transport charge.The group, which includes scientists from Ames Laboratory in Iowa, Iowa State University (ISU), and San Diego State University, created single-crystal versions of two iron arsenide superconductors, a class of superconductors currently being examined by researchers across the globe. However, most of these researchers are studying polycrystalline varieties, with only recent work coming out on single crystals.The first paper1 describes the barium/iron/arsenic superconductor BaFe2As2 and a compound derived from it that contains a slightly different amount of barium as well as small amounts of potassium (The potassium, in this context, is a “dopant” material that bolsters the material’s properties. Doping is common in superconductivity research.)”Growing single-crystal versions of these materials allows us to study their ‘anisotropic’ superconducting properties—their tendency to display superconductivity along one axis but not others,” said the group’s spokeperson, Ames Lab and ISU scientist Paul Canfield, to PhysOrg.com.The major result published in the first paper is a determination of the highest magnetic field the superconducting state can withstand (called the upper critical field) and an evaluation of how anisotropic it is. Some superconductors are extremely anisotropic, and so fully understanding them requires good measurements of this behavior.Canfield and his group show in their second paper2 that their single-crystal growth method can be applied to another iron arsenide compound, SrFe2As2 (where “Sr” is strontium).And in the third paper3, the researchers discuss a new member of the iron arsenides. The compound is CaFe2As2 (“Ca” is calcium) and it had never before been identified as a member of that particular crystallographic family.”The discovery of CaFe2As2 was very exciting,” said Canfield. “We learned that at a temperature of 170 K [degrees Kelvin, here equal to about -150 degrees Fahrenheit] the material undergoes exceptionally clear changes to its structure and magnetic behavior.”This type of temperature-induced changes are known as “first-order” transitions, and understanding how they occur—a task made easier when the changes are obvious—will aid in scientists’ knowledge of superconducting materials.The fourth paper4 in the series further documents their study of CaFe2As2, detailing exactly why the material can be classified as a superconducting iron arsenide. The researchers found that at modest pressures the structural and magnetic changes that occur at 170 K are suppressed and the material becomes a superconductor.”This means that, from a basic science point of view, CaFe2As2 offers a clean model system that seems to encompass all of the salient features of these compounds (structural, magnetic and superconducting phase transitions) and that its behavior can be tuned with pressure,” Canfield said. “This is a very exciting discovery that may help guide the way to understanding this new family of superconductors.”Citations:1Phys. Rev. B 78, 014507 (2008)2Phys. Rev. B 78, 024516 (2008)3Phys. Rev. Lett. 101, 057006 (2008)4Phys. Rev. B 78, 014523 (2008)Copyright 2008 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: ‘Single-Crystal’ Superconductors are a Big Step for the Field (2008, August 28) retrieved 18 August 2019 from https://phys.org/news/2008-08-single-crystal-superconductors-big-field.html A sample of a potassium-doped iron arsenide superconductor, shown on a millimeter grid. Image courtesy the American Physical Society [N. Ni et al. (10 July 2008). Anisotropic thermodynamic and transport properties of single-crystalline Ba1－xKxFe2As2 (x=0 and 0.45). Physical Review B, Vol 78, p014507, Fig 1] 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.
Is that your final answer? Study suggests method for improving individual decisions More information: How social influence can undermine the wisdom of crowd effect, PNAS, Published online before print May 16, 2011, doi: 10.1073/pnas.1008636108AbstractSocial groups can be remarkably smart and knowledgeable when their averaged judgements are compared with the judgements of individuals. Already Galton [Galton F (1907) Nature 75:7] found evidence that the median estimate of a group can be more accurate than estimates of experts. This wisdom of crowd effect was recently supported by examples from stock markets, political elections, and quiz shows [Surowiecki J (2004) The Wisdom of Crowds]. In contrast, we demonstrate by experimental evidence (N = 144) that even mild social influence can undermine the wisdom of crowd effect in simple estimation tasks. In the experiment, subjects could reconsider their response to factual questions after having received average or full information of the responses of other subjects. We compare subjects’ convergence of estimates and improvements in accuracy over five consecutive estimation periods with a control condition, in which no information about others’ responses was provided. Although groups are initially “wise,” knowledge about estimates of others narrows the diversity of opinions to such an extent that it undermines the wisdom of crowd effect in three different ways. The “social influence effect” diminishes the diversity of the crowd without improvements of its collective error. The “range reduction effect” moves the position of the truth to peripheral regions of the range of estimates so that the crowd becomes less reliable in providing expertise for external observers. The “confidence effect” boosts individuals’ confidence after convergence of their estimates despite lack of improved accuracy. Examples of the revealed mechanism range from misled elites to the recent global financial crisis. Social inﬂuence effect: Social inﬂuence diminishes group diversity without diminishing the collective error. Typical examples of experimental sessions for three information conditions, displaying ﬁve individual responses. Image (c) PNAS, doi: 10.1073/pnas.1008636108 Citation: Information sharing interferes with ‘wisdom of crowds’: study (2011, May 17) retrieved 18 August 2019 from https://phys.org/news/2011-05-wisdom-crowds.html (PhysOrg.com) — A statistical phenomenon, called the Wisdom of Crowds, happens when a group of individuals make guesses and the average of the guesses reveal accurate average answers. However, researchers have discovered that when the individuals are made aware of other participant’s guesses, there is a clear disruption to the accuracy of the guesses. © 2010 PhysOrg.com The study, led by mathematician Jan Lorenz and sociologist Heiko Rahut from Switzerland’s ETH Zurich published their recent findings in Proceedings of the National Academy of Sciences, showing that even a small amount of social influence on a group can interfere with the Wisdom of Crowd effect.For the study, researchers brought in 144 students and placed them in isolated locations and asked them to guess things like how many crimes were committed in 2006 and what the population density of Switzerland was. Based on the accuracy of their answers, participants were given a small monetary award and then the process was repeated for a total of four rounds. The students were broken up into two groups, with one group receiving information on what other peers had guessed and the other remaining isolated.As each round continued, the group with no influence by other peers showed their results becoming more accurate. The individuals that received information on what their peers were guessing however showed less accuracy in their answers.Researchers found that those receiving social input from their peers either led individuals to second guess themselves or, seeing others may have answered the same, become more confident in their incorrect responses. According to the results of the study, the Wisdom of Groups phenomenon appears to only be accurate when the individuals in the group are not aware or influenced by others in the group. 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 further
Citation: Germany sets weekend record for solar power (2012, May 30) retrieved 18 August 2019 from https://phys.org/news/2012-05-germany-weekend-solar-power.html Explore further Image: Array Technologies That comparison is significant because, in the wake of the Fukushima nuclear disaster in Japan, Germany abandoned nuclear energy endeavors. They shut down eight plants in favor of safer options and instead shouldered the task of further developing renewable energy sources. Allnoch said the data is based on information from the European Energy Exchange (EEX), based in Leipzig.Germany aggressively supports alternative energy sources and, by the year 2022, Germany expects to shutter its remaining nine nuclear power plants. The lack of these nuclear power facilities will create a gap in the country’s energy infrastructure, however. Germany is looking toward sources such as solar, wind and biomass.That support and commitment have come at a price. A 2012 Environment Ministry report showed that German taxpayers pay an extra four billion euros per year on top of their electricity bills to support solar power.Allnoch and his supporters would prefer to look at the “price” context in another way. “Even with all the safety precautions”, he said, there is still a risk at nuclear plants. “A global phaseout would be ideal but is not likely to happen soon.”As for costs, he said that while everyone worries about costs, the markets are shifting. He said once the uncertainty calms down, “we will see that we can do without nuclear power.”In relegating nuclear energy to the past, the road to replace it may be rocky, he added, but it is do-able. “We need to rise to this challenge.”The new record-breaking figures from Germany, however, do not quiet some energy experts who stress that without good storage strategies for excess power, such record-breaking numbers are not meaningful. They say the real point is to get consistently large percentages of power from renewable sources. German cabinet passes nuclear exit bill © 2012 Phys.Org (Phys.org) — Solar power plants in Germany have set a new record. “Never before anywhere has a country produced as much photovoltaic electricity,” said Norbert Allnoch, Germany’s director of the Institute of the Renewable Energy Industry in Muenster. The plants peaked at 22 gigawatts of output for a few hours over the weekend, on Friday and Saturday. The numbers are important in that they yielded almost half the country’s energy mid-day electricity needs. The 22 gigawatts is up from 14 GW a year ago. Also, this 22 gigawatts of output is equal to about 20 nuclear plants. 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.
MYO armbands The next interface: Electrical fields, MGC3130, and your hand (w/ Video) © 2013 Phys.org More information: getmyo.com/ Explore further (Phys.org) —”Wave goodbye to camera-based gesture control.” That is the confident directive coming from a one-year-old Waterloo, Ontario, startup called Thalmic Labs. The company is prepared to ship its next batch of wearable-computing armbands for device controls early next year. The $149 armbands called MYO do not require cameras in order to track hand or arm movements. The armbands can wirelessly control and interact with computers and other digital consumer products by recognizing the electric impulses in users’ muscles. “We work day and night,” said one team member, and their steadfastness is fed by a notion that the MYO could revolutionize the way people interact with technology. Thalmic Labs said they are accepting pre-orders for the second shipment of MYOs shipping early 2014. The MYO is worn around the forearm; its purpose is to control computers, phones, and other devices, sending the data via Bluetooth. Windows and Mac operating systems are supported and APIs will be available for iOS and Android.Bluetooth 4.0 Low Energy (BLE) is used for the MYO to communicate with the paired devices. (Bluetooth version 4.0 is the most recent version of Bluetooth wireless technology. It includes a low-energy feature promoted as good news for developers and manufacturers of Bluetooth devices and applications—enabling markets for devices that are low-cost and operate with low-power wireless connectivity.)The MYO specs include on-board, rechargeable lithium-ion batteries and an ARM processor. Also part of the mix are the company’s proprietary muscle-activity sensors and a six-axis inertial measurement unit.A user’s gestures and movements are actually detected in two ways: muscle activity and motion sensing. The Thalmic team says that when sensing the muscle movements of the user, the MYO can detect changes down to each individual finger. Also, when tracking arm and hand positions, the MYO picks up subtle movements and rotations in all directions.Right now, as indicated in their newly released video of the company, Thalmic Labs hopes for greater things for MYO via a developer community. They expect an official developer program to be up and running in the next few months. They pride themselves in groundbreaking technology, as a team with specialties from electrical engineering to embedded system design. Nonetheless, they are looking to developers for innovative ideas in applications. Citation: MYO armband to muscle into computer control (w/ video) (2013, April 28) retrieved 18 August 2019 from https://phys.org/news/2013-04-myo-armband-muscle-video.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.
(Phys.org) —A pair of researchers, one with the University of Alaska, the other with Independent, Auke Bay are suggesting in a paper they’ve had printed in Proceedings of the National Academy of Sciences, that global warming is partially responsible for large increases in pink salmon populations in North America and Asia. Alan Springer and Gus van Vliet claim that rising ocean temperatures are at least partly to blame for increased pink salmon populations due to an increase in the amount of available food. Explore further Citation: Global warming may be causing surge in numbers of pink salmon (2014, April 1) retrieved 18 August 2019 from https://phys.org/news/2014-04-global-surge-pink-salmon.html Scientists have blamed global warming for smaller numbers of many fish species—a recent Intergovernmental Panel on Climate Change, for example, claimed that rising ocean temperatures (due to global warming) is causing a reduction in numbers of tuna and cod populations in the Atlantic Ocean. Now it appears that global warming may actually cause some fish populations to increase.Springer and Vliet suggest that pink salmon swimming in warmer water during their formative years are exposed to more food (zooplankton, small fish and squid, etc.) which allows them to eat more, and then later, to produce more offspring. It leads to more fish in the sea, they say, which in turn might have a negative impact on other sea life that feed on the same prey. They focused their study on sea life in the Aleutian Islands and the Bering Sea, looking to find out if burgeoning fish populations are causing a decrease in bird populations. In sampling both populations, they noted that second year salmon were more numerous and that bird populations sank as salmon surged, due to less egg laying and lowered survival rate of chicks—signs of nutritional stress.Whatever the cause, what is undeniable is that pink salmon are thriving and are beginning to take over ecosystems previously dominated by other types of salmon or even other types of animals altogether. Complicating the situation is the fact that many of the salmon swimming freely in the ocean came to be there after being released by fish hatcheries in an effort to boost harvests.Pink salmon populations have been rising since the 1970’s, roughly the same time frame as global warming—so much so that some have begun suggesting that it’s a problem easily solved by allowing fishermen to catch more. While that may help solve the problem of too many fish, it doesn’t really answer the question of whether global warming is truly to blame, and if it is, what other changes it may be causing in poorly understood ocean ecosystems. Oncorhynchus gorbuscha. Credit: Timothy Knepp/U.S. Fish and Wildlife Service Journal information: Proceedings of the National Academy of Sciences Researchers uncover some good news for BC’s troubled salmon populations More information: Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea, PNAS, Alan M. Springer, DOI: 10.1073/pnas.1319089111AbstractClimate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem. © 2014 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.
The sand dune ridges along the northern coast of Peru came about, the researchers claim, due to earthquakes loosening sand deposits in the Chira valley. That sand was eventually swept into rivers which carried it to the sea. Currents then carried it north eventually depositing it along the shoreline, building up over time into large ridges. Radiocarbon dating of charcoal remnants from fire pits atop some of the ridges has shown them to have formed from over 5000 years ago to as recently as 400 years ago. Excavating one of the existing ridges, the two researchers report, revealed mollusk shells which because there were so many of them, served as a shield against the wind, which would have blown the sand off the ridges long ago, had not the shells been there to offer protection.The Inca, the researchers report, lived along the shorelines of northwest South America for thousands of years, catching, cooking and eating mollusks and tossing the shells aside as they sat atop a ridge. The result was millions of shells littering the surface of the ridges, forming armor of sorts, which allowed the ridges to remain intact far longer than they would have otherwise. But, then, the Spanish arrived, conquering the Incas and forcing them to move inland. After that, the shell littering ceased—without a constantly rejuvenated suit of armor, many of the ridges succumbed to the winds and vanished. Thus, the coast was altered in a way that neither the Inca nor their conquerors could have possibly imagined. Space image: Aorounga Crater, Chad (Phys.org) —A study by a pair of researchers with the University of Maine suggests that the northern coast of Peru may have been altered due to population shifts as a result of the Spanish conquest in the 1500’s. In their paper published in Proceedings of the National Academy of Sciences, Daniel Belknap and Daniel Sandweiss describe a field study they conducted in the area that suggested that Inca living on the coast prior to the Spanish conquest, may have inadvertently been supporting the existence of sand ridges by discarding mollusk shells. After they left, it appears, some of the sand ridges were blown away by the wind. Citation: Study indicates Spanish conquest of Peru may have resulted in changes to coastal shoreline (2014, May 20) retrieved 18 August 2019 from https://phys.org/news/2014-05-spanish-conquest-peru-resulted-coastal.html Journal information: Proceedings of the National Academy of Sciences Surface of ridge J and test pit surface test pit-Chira-1997-number 4: STP-C-97-4. Credit: PNAS, doi: 10.1073/pnas.1404568111 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 further © 2014 Phys.org More information: Effect of the Spanish Conquest on coastal change in Northwestern Peru, Daniel F. Belknap, PNAS, DOI: 10.1073/pnas.1404568111AbstractWhen Francisco Pizarro and his small band of Spanish conquistadores landed in northern Peru in A.D. 1532 to begin their conquest of the vast Inca Empire, they initiated profound changes in the culture, language, technology, economics, and demography of western South America. They also altered anthropogenically modulated processes of shoreline change that had functioned for millennia. Beginning with the extirpation of local cultures as a result of the Spanish Conquest, and continuing through today, the intersection of demography, economy, and El Niño-driven beach-ridge formation on the Chira beach-ridge plain of Northwestern Peru has changed the nature of coastal evolution in this region. A similar event may have occurred at about 2800 calibrated y B.P. in association with increased El Niño frequency.
Schematic picture of the Earth’s interior. On the right side is the example of the part of the two-dimensional wide scan of x-ray diffraction image of Fe, Al-bearing bridgmanite, on the left side is the crystal structure of pure Fe-bridgmanite. Credit: Leyla Ismailova/University of Bayreuth More information: L. Ismailova et al. Stability of Fe,Al-bearing bridgmanite in the lower mantle and synthesis of pure Fe-bridgmanite, Science Advances (2016). DOI: 10.1126/sciadv.1600427AbstractThe physical and chemical properties of Earth’s mantle, as well as its dynamics and evolution, heavily depend on the phase composition of the region. On the basis of experiments in laser-heated diamond anvil cells, we demonstrate that Fe,Al-bearing bridgmanite (magnesium silicate perovskite) is stable to pressures over 120 GPa and temperatures above 3000 K. Ferric iron stabilizes Fe-rich bridgmanite such that we were able to synthesize pure iron bridgmanite at pressures between ~45 and 110 GPa. The compressibility of ferric iron–bearing bridgmanite is significantly different from any known bridgmanite, which has direct implications for the interpretation of seismic tomography data. Journal information: Science Advances (Phys.org)—A diverse team of researchers with members from Germany, France, Russia and the U.S. has subjected a sample of bridgmanite to conditions believed to be present at Earth’s lower mantle and has found that it remained stable. In their paper published in the journal Science Advances, the team describes the testing they conducted, what they found and their theory regarding the dynamo effect that is, perhaps, the source of the planet’s magnetic field Citation: Bridgmanite sample found to remain stable at lower mantle conditions (2016, July 18) retrieved 18 August 2019 from https://phys.org/news/2016-07-bridgmanite-sample-stable-mantle-conditions.html Developing a picture of the Earth’s mantle Explore further Studying the interior of planet Earth is difficult due to the huge scale involved—researchers cannot simply drill a hole all the way to the core to grab samples of material. For that reason, they have developed and used other tools such as seismic monitors to learn more. Though the have learned much, there is still a lot that is unknown or uncertain. One of these uncertainties is the makeup of the planet’s lower mantle—the part just next to the core. Prior research has indicated that it is likely a mineral called bridgmanite. Other researchers have suggested that bridgmanite would not be stable under the very high temperature and pressure that would exist in the lower mantle. In this new effort, the researchers sought to settle this debate by bringing samples of bridgmanite into their lab and testing it.To exert very high pressure on the sample similar to that believed to exist in the lower mantle, the researchers used laser-heated diamond anvil cells—creating a vice-like grip by squeezing a very small sample between two diamonds and focusing a laser on them. The team ran several such experiments at different temperatures and pressures, maxing out at 23 gigapascals and 1,800 Kelvin. They then used X-rays to examine the samples to see how they held. The team reports that the samples held up very well and concluded that bridgmanite is stable under the conditions believed to exist at the lower mantle.The team found that when samples contained different amounts of iron, there were differing levels of stability. Those differences, they suggest, could offer an explanation for seismic activity deep in the planet which could play a role in establishing the dynamo that is responsible for the planet’s magnetic field. © 2016 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.
The physicists, Anthony Bartolotta, a graduate student at Caltech, and Sebastian Deffner, Physics Professor at the University of Maryland Baltimore County, have written a paper on the Jarzynski equality for quantum field theories that will be published in an upcoming issue of Physical Review X.The work address one of the biggest challenges in fundamental physics, which is to determine how the laws of classical thermodynamics can be extended to the quantum scale. Understanding work and heat flow at the level of subatomic particles would benefit a wide range of areas, from designing nanoscale materials to understanding the evolution of the early universe.As Bartolotta and Deffner explain in their paper, in contrast to the large leaps made in the “microscopic theories” of classical and quantum mechanics during the past century, the development of thermodynamics has been rather stagnant over that time. Although thermodynamics was originally developed to describe the relation between energy and work, the theory traditionally applies only to systems that change infinitely slowly. In 1997, physicist Christopher Jarzynski at the University of Maryland College Park introduced a way to extend thermodynamics to systems in which heat and energy transfer processes occur at any rate. The fluctuation theorems, the most prominent of which is now called the Jarzynski equality, have made it possible to understand the thermodynamics of a wider range of smaller, yet still classical, systems.”Thermodynamics is a phenomenological theory to describe the average behavior of heat and work,” Deffner told Phys.org. “Originally designed to improve big, stinky heat engines, it was not capable of describing small systems and systems that operate far from equilibrium. The Jarzynski equality dramatically broadened the scope of thermodynamics and laid the groundwork for stochastic thermodynamics, which is a new and very active branch of research.” Thermodynamic laws that describe heat and energy are being extended to the quantum scale. Source: Pexels. Photograph by Paweł Kadysz Stochastic thermodynamics deals with classical thermodynamic concepts such as work, heat, and entropy, but on the level of fluctuating trajectories of atoms and molecules. This more detailed picture is particularly important for understanding thermodynamics in small-scale systems, which is also the realm of various emerging applications.It wasn’t for another decade, however, until the Jarzynski equality and other fluctuation theorems were extended to the quantum scale, at least up to a point. In 2007, researchers determined how quantum effects modify the usual interpretation of work. However, many questions still remain and overall, the area of quantum stochastic thermodynamics is still incomplete. Against this backdrop, the results of the new study represent a significant advance.”Now, in 2018 we have taken the next big step forward,” Deffner said. “We have generalized stochastic thermodynamics to quantum field theories (QFT). In a certain sense we have extended stochastic thermodynamics to its ultimate range of validity, since QFT is designed to be the most fundamental theory in physics.”One of the keys to the achievement was to develop a completely novel graph theoretic approach, which allowed the researchers to classify and combine the Feynman diagrams used to describe particle behavior in a new way. More specifically, the approach makes it possible to precisely calculate infinite sums of all the possible permutations (or arrangements) of disconnected subdiagrams describing the particle trajectories.”The quantity we were interested in, the work, is different than the quantities usually calculated by particle theorists and thus required a different approach,” Bartolotta said.The physicists expect that the results will allow other scientists to apply the fluctuation theorems to a wide variety of problems at the forefront of physics, such as in particle physics, cosmology, and condensed matter physics. This includes studying things like quantum engines, the thermodynamic properties of graphene, and the quark gluon plasma produced in heavy ion colliders—some of the most extreme conditions found in nature.In the future, the physicists plan to generalize their approach to a wider variety of quantum field theories, which will open up even further possibilities. What is quantum in quantum thermodynamics? More information: Anthony Bartolotta and Sebastian Deffner. “Jarzynski Equality for Driven Quantum Field Theories.” Physical Review X. DOI: 10.1103/PhysRevX.8.011033. Also at arXiv:1710.00829 [cond-mat.stat-mech] Citation: Physicists extend stochastic thermodynamics deeper into quantum territory (2018, February 13) retrieved 18 August 2019 from https://phys.org/news/2018-02-physicists-stochastic-thermodynamics-deeper-quantum.html © 2018 Phys.org Journal information: Physical Review X 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. Physicists have extended one of the most prominent fluctuation theorems of classical stochastic thermodynamics, the Jarzynski equality, to quantum field theory. As quantum field theory is considered to be the most fundamental theory in physics, the results allow the knowledge of stochastic thermodynamics to be applied, for the first time, across the full range of energy and length scales. Explore further
Raising the issue of gender equality in cinema, Arth made an extraordinary impact back in 1980s. This semi-autobiographical film directed by Mahesh Bhatt in 1982 changed the face of Indian cinema forever and is back with a bang as a theatrical production. After the recent success of his plays The Last Salute and Trial of Errors which also launched his latest protégé Imran Zahid, the duo are now pairing up again for the dramatic adaptation of Arth Also Read – ‘Playing Jojo was emotionally exhausting’.Bhatt feels that Arth was a classic film that raised the issue of gender equality way back in the 80’s. ‘The film looked at the issue of women emancipation like no Indian dramatic work ever has. No one has been able to better what Arth highlighted in the world of movies or in theatre. I think the 21st century India needs to be experience the theme of Arth through theatre’ says the filmmaker ahead of translating the screenplay for the stage. Arth was way ahead of its time and Bhatt feels that subject will strike a chord even with today’s generation. It looked at the bold subject of extra marital relationships was also remembered for its memorable soundtrack. Also Read – Leslie doing new comedy special with NetflixBelieving that the fabric of society has not gone under a complete change over the yearsm the director adds, ‘The issues with regards to our society that were raised in Arth are relevant in even in todays times. Theater has given me an entirely new outlet and after staging two successful plays The Last Salute and Trial of Errors I took this decision.I think adapting such a piece of art into a theatrical adaptation will not be an easy task but I am ready for this test. I feel this medium has help connecting with audience in all together different way,’ he adds.Delhi-based actor Imran Zahid , who earlier essayed the role of Muntadar Al Zaidiin The Last Salute and of journalist Rehan in Trial of Errors is all gearing up for this new assignment.‘Mahesh Bhatt is all set to recreate magic of film in a theatrical play. It’ll be a big challenge for me to play the lead but I am up for it,’ says Imran.
Festivities are in the air, with the seventh weekend of Dilli Haat Utsav geared up. The flagship tourism promotion festival of Delhi Tourism in collaboration with Department of Art, Culture and Languages, has successfully reached its 7th weekend. Dilli Haat Utsav began on 13 September and is scheduled to continue in the same spirit 31 March.Lively evenings full of fun, frolic and entertainment are being offered with an exclusive journey to cultural territories. Artists from institutions like Hindi Academy, Punjabi Academy, Sahitya Kala Parishad etc are showcasing their talent at Dilli Haats every weekend. This series of festival is marked by unique music and dance performances. Also Read – ‘Playing Jojo was emotionally exhausting’This weekend’s schedule focuses on artistic diversity of the country, and promises a cocktail of different and unique cultures of India. Artists from every nook and corner of the city have been invited to present their talent and captivate the audience with a joyful evening full of divergent artistic expressions.Dilli Haats are now coming out as the new cultural joints in Delhi. Festivities and celebrations rarely end here. Local as well as international tourists are offered a lively and active hangout offering window to whole of India. Also Read – Leslie doing new comedy special with NetflixAlso new and seasoned artists have been given an organised platform to perform. Dilli Haat Utsav offers them a systematic space to gather fans and make a name for themselves. The initiative aims to strengthen options for cultural delights in the city. People are offered with an alternative arena for spending time and discovering India’s crafts, culture and cuisine.Dilli Haats offers food from diverse Indian cuisines under one roof and at economical prices. Take a nibble from Manipur, taste Punjab and head Mumbai for some Vada Pao. Dilli Haats’ huge footfall has also contributed in increasing sales of handicraft and handloom artists. Craftsmen from around the country have put up stalls to directly link with buyers and sell their product without the involvement of any middlemen.Where : Dilli Haat (INA, Pitampura, Janakpuri) When: 1 and 2 November
Switzerland’s 17-time Grand Slam winner Roger Federer on Monday said he still believed Rafael Nadal was the favourite to win the French Open next month despite the Spanish star’s troubled start to the clay court season.Federer, who took his sole French Open title in 2009, this week is refining his own clay court game at the Istanbul Open, the first ATP World Tour event to be held in Turkey and the first time that Federer has visited the country.But Nadal, who with the exception of Federer’s win has taken every French Open since 2005 to make nine in total, has shown a dip in form over the past weeks, failing to get past the third round at last week’s Barcelona Open. Federer said he believed that Nadal was still the man to beat on the red clay of Roland Garros, along with the in-form Serbian world number one Novak Djokovic. Also Read – Khel Ratna for Deepa and Bajrang, Arjuna for Jadeja“At the French Open, Rafa for me is still the favourite alongside Djokovic who has been playing so well. Even though his (Nadal’s) form is not as good as in previous years, I still believe when the French Open rolls around he is going to be very difficult to beat,” he told a news conference in Istanbul.Federer, 33, is himself looking for his own form on the slower clay after a long hard court season, having lost in the third round to Gael Monfils at the Monte Carlo Masters this month. But he said the Istanbul event was ideal for his preparations. “It’s about getting used to the sliding, deciding how aggressive I want to play,” said the world number two.Federer, who so far has been unable to add to his sole French Open win in 2009 and won his last grand slam at Wimbledon in 2012, acknowledged that this year’s French Open “is clearly a big goal of mine.” “But to play well at the French Open I need confidence. I hope that I can pick that up in Istanbulm,” said the former Swiss world no. 1.
Amalgamating art and infrastructure to create something new in the field of real estate, not only demands an innovative approach but also a vision to create a better future. In a unique initiative, Kolkata-based real estate major Hiland Group is tying up with one of India’s best-known artists, Paresh Maity, to set up ‘Bonochhaya’, a 100-crore signature Tagore-inspired real estate project at Santiniketan. The project envisages setting up villas and row houses in a 12-acre gated community. It is situated on the main Illambazar road. In the first phase, the project will have 35 exclusive villas and 167 row houses which will cost between Rs 30 lakh to Rs 55 lakh. Also Read – ‘Playing Jojo was emotionally exhausting’“This is the country’s first project in which an artist of Paresh Maity’s stature will be directly involved in the conceptualisation and aesthetics. Inhabitants of ‘Bonochhaya’ will be able to enjoy the artist’s creative vision with installations and shared spaces showcasing unique works of art,” said Nandu Belani, Director of the Hiland Group. “Paresh Maity’s vision will help to transform ‘Bonochhaya’ into a unique experience by adding context, aesthetic value, and greater purpose to the environment. We have seen that many home-buyers have a strong knowledge and love for art. ‘Bonochhaya’ will be for them”, added Nandu Belani. Also Read – Leslie doing new comedy special with Netflix“Santiniketan is in my blood. Art is a fundamental aspect of ‘Bonochhaya’. I have been deeply inspired by Gurudev Rabindranath Tagore and I hope to pay tribute to the genius in his own land in my own way – through my art. I plan to use a lot of locally available materials and showcase local talent in ‘Bonochhaya’ through large-size installations, murals etc. This will be a one-of-its-kind project,” said Paresh Maity.For connoisseurs, ‘Bonochhaya’ will offer a veritable art walk through Paresh Maity’s oeuvre, with sketches that adorn the area around the name ‘Bonochhaya’, and murals and installations all round for residents to enjoy. Maity’s Tagore-inspired creations will give the residents company in the sitting areas. A treat for the senses, these paintings and sculptures will make ‘Bonochhaya’ unique in every sense and thrill art lovers and create a rich cultural environment.
Usually, children with symptoms of attention deficit hyperactivity disorders (ADHD), a common behavioural disorder in kids, like poor concentration, hyperactivity and learning difficulties, tend to improve with age.However, the disorder does not improve in some kids and one reason may be the persistent parental criticism, reveals a new research.“Children with ADHD, whose families continued to express high levels of criticism over time, failed to experience the usual decline in symptoms with age and instead maintained persistent, high levels of ADHD symptoms,” said Erica Musser, assistant professor at Florida International University in US. Also Read – ‘Playing Jojo was emotionally exhausting’The researchers studied a sample of 388 children with ADHD and 127 without, as well as their families, over three years. Of the children with ADHD, 69 per cent were male, 79 per cent were white and 75 per cent came from two-parent households. They measured changes in ADHD symptoms over that period and measured the parents’ levels of criticism and emotional involvement.Parents were asked to talk about their relationship with their child uninterrupted and were then rated by experts for levels of criticism — harsh, negative statements about the child, rather than the child’s behaviour —and emotional over-involvement — overprotective feelings toward the child, the study, published in the Journal of Abnormal Psychology, showed. Only sustained parental criticism was associated with the continuance of ADHD symptoms in the children who had been diagnosed with ADHD, the study concluded.
Kolkata: Be it in any corner of the world, breastfeeding mothers, knowingly or unknowingly, face criticism for feeding their babies in public. As it continues to be a deeply held taboo in our society — the shamers also keep rising in large numbers.In a weird incident, a mother was asked by a staff of South City Mall to breastfeed her child inside the washroom instead out in the open. When the woman narrated the incident in detail on a social media channel, the admin of the South City Mall Facebook page replied to her post saying that breastfeeding is not allowed on the Also Read – Rain batters Kolkata, cripples normal lifefloor of the mall. Within sometime, the post went viral with several people sharing the thread and criticising the comment. However, the mall authority removed the comment. The incident occurred on last Tuesday when a woman was breastfeeding her baby on the floor of the mall. On noticing her breastfeeding, a security person allegedly asked her to go to a washroom and do the same as apparently it is not allowed at the mall premises for various reasons. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedThough she asked about a place where she could go and feed her child as there was no designated place, the security person again asked her to move inside a washroom. Later, the woman took to Facebook to vent her anger. The mall authority was quick enough to reply saying an open place like their mall is not a place for breastfeeding which should be done at home. The comment read: “Please make sure you do your home chores at your home and not in the mall or at least plan it before hand…” It also said the mall authority cannot compromise the privacy of other people in public places. Though the mall authority claim that the privacy of other people in the mall was at risk, surprisingly, not a single person raised any objection on seeing the baby being breastfed. The admin, however, removed the comment and apologised. Outrage poured in from various corners of the society with people posting on their Facebook page. People reacted and condemned the mall authority on various other posts related to shopping products on their Facebook page. Many of them even feel the mall should be boycotted where a baby was denied to be breastfed. The chairperson of the state woman’s commission, Leena Ganguly condemned the statement made on behalf of the authority. She strongly reacted and said the woman’s commission is going take steps and will ensure that no such incidents take place in the state again. “We are concerned about the matter. The statement from the authority is not at all acceptable. If they had any such rule in place, they should have mentioned and displayed it. They did not because there is no such real restriction against it. We will inform the concerned department about it. This is human rights violation,” she added.
One should eat carefully to stay fit and fabulous but keeping a check on your diet before going to bed needs extra attention as some food items have the tendency to disturb your sleep if taken regularly.Chocolate: Dark chocolate is considered to be healthy for containing magnesium and antioxidants, but it also contains caffeine, which could keep you awake. So one should avoid it specially during night time as it may create hindrance in your sound sleep. Also Read – Add new books to your shelfNut Butter: Nut butter is a healthy source of fat. Also, it may help in losing weight but fats digest slow and may remain present in your stomach all night if consumed in large quantities, hence, may lead to disturbed sleep. So keep high fat foods like (nuts, cheese, cream sauces) relatively low at night.Chilies and spicy foods: Chilies are healthy if made with the right mix of ingredients, but they are spicy, and may end up causing heartburn, if consumed late in the night and may result in killing your sleep. Heavily spiced foods should be avoided at night because if your sleep is disturbed, your health will deteriorate. Also Read – Over 2 hours screen time daily will make your kids impulsiveGreasy or fat-filled foods: Greasy, heavy, fatty foods would make your stomach overwork throughout night, resulting in disturbed sleep and making you sluggish next morning. So fast food, nuts, ice cream, or super cheesy foods should be avoided before bed. Chinese Food: This is another food item that is important to avoid during night as the MSG (Monosodium Glutamate, flavour enhancer) found in Chinese food works in a similar manner as the caffeine would do in the body, making it really difficult to fall asleep. Milk: Though we consider milk to be a rich source of protein and calcium, it may kill your sleep if you drink it before bed because of its lactose content that can create digestive issues in many individuals. Especially if you are lactose intolerant, you should avoid it.Red meat and other non-veg items: Eating red meats and other non veg items in large amounts at night will remain in your digestive system for long time and it will make it hard for you to get sound sleep while you’re digesting. So red meat and eating a large portion of chicken or pork may affect you the worst leading to troubled sleep along with weight gain.Celery: Celery is a vegetable that acts as a diuretic in the body, which results in making you pee a lot. Hence you should avoid taking celery at night.Rice: If large amounts of rice is consumed at night, it encourages your body to store excess fat that it doesn’t need and make it harder to lose weight. It can also lead to water retention.
With the arrival of winter, Shangri-La’s Eros Hotel in the national Capital is all set and delighted to welcome its guests to experience traditional Southern Italian cuisine created exclusively by Italian Chef Luigi Ferraro under the guidance of the Executive Chef Neeraj Tyagi.Laying emphasis on the authenticity of hearty Italian dishes, Sorrento offers a family style Italian feast for its patrons. Alfresco seating arrangement in addition to soothing music and the goodness of Italian flavours, this feast at Sorrento will take their diners to a journey through the streets of Italy. Also Read – Add new books to your shelfWith an exquisite arrangement of buffet and table services, the Italian brunch offers a selection of classic Italian dishes served in family style. One would notice a variety of Italian dishes ranging from Neapolitan Pizzas, homemade style Pastas, and Risottos with choice of grilled meats or seafood. An Antipasti counter offers Seasonal Grilled Vegetable Salad with Parmesan flakes. One could also find an array of an exotic cheese selection including Parmesan, Asiago, Fontal, Gorgonzola, Pecorino, Provolone, and Taleggio. Cold cuts comprising Italian cured meat sliced live-Parma ham, Coppa, Mortadella, Seafood Salad, Baked Sardines with Chili and Parmesan, Classic Caesar Salad, Sicilian Shrimp Salad, Octopus Carpaccio and lot more are some of the other lip-smacking options to go for. Also Read – Over 2 hours screen time daily will make your kids impulsiveCicchetti, which are basically small side dishes, also offers Bruschetta with choices of seasonal tomato, basil, Rocket salad, Roast Chicken, wild mushroom and Parmesan snow. Spiedini preparations deserve a mention too as it provides foodies with free range of Chicken, Peruvian Chili and Romesco Sauce, spicy Lamb Piccata, wild mushroom, Coriander pesto, Heirloom peppers stuffed goat cheese and Focaccia Farcita.The menu also consists of some scrumptious desserts in the Dolce Section, which include Tiramisu, Pastiera Napoletana, Cannoli, Panna cotta, Fresh Fig and Ricotta Crostata, Genoise, Zuccotto, Chocolate Praline Tart, Tarte au Citron and Gorgonzola Mascarpone delight, among others. The menu is clubbed with an extensive selection of in-house beverages as well.
Kolkata: A woman was caught smoking inside the washroom of a flight on Sunday afternoon. She was handed over to Netaji Subhas Chandra Bose International (NSCBI) Airport police station and was released on bail later.According to airport sources, the woman is a teacher by profession in a English medium school in South Kolkata and was travelling from Guwahati in an Indigo Airline’s flight. While the flight was in the air, she was caught smoking by the crew members inside a washroom. She was immediately detained. After the flight landed at NSCBI Airport, the pilot of the flight lodged a complaint at NSCBI Airport police station and handed her over to the police. A case was initiated against her based on the Smoking and Tobacco Consumption (Prohibition) Act.
Illambazar (Birbhum): Brushing aside Prime Minister Narendra Modi’s allegations that there is no democracy in Bengal, Chief Minister Mamata Banerjee said he is not speaking the truth and BJP is stifling the voice of democracy and creating trouble everywhere.Modi had alleged that democratic movements have been curbed in Bengal in an interview to a private television channel on January 1. She was addressing a gathering in connection with public distribution here on Thursday afternoon. “He is not speaking the truth. BJP is choking the voice of democracy and any one criticising them is being pulled up. BJP is creating trouble everywhere.” Also Read – Rain batters Kolkata, cripples normal lifeBanerjee said: “The people in Bengal are living peacefully and their democratic rights have not been curtailed. On the contrary, BJP is demolishing the institutions and creating trouble everywhere.” She said the people in Bengal have been practicing Hinduism since birth. “We have heard about the Vedas from our birth and from our early childhood learnt to respect the religion of others. The Hindus, Muslims, Christians and Sikhs have lived peacefully for several generations in Bengal. But now some people wielding lathis and wearing headbands are teaching us which religion we will have to follow. We believe in the philosophy of live and let live,” the Chief Minister added. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedLauding folk artistes, Banerjee said they are proud of Bengal. “Baul music has been appreciated by people in foreign countries and they are proud of Bengal,” she said, adding that there was a time when people did not respect the folk artistes and their financial condition turned from bad to worse. The state government is now giving a stipend of Rs 1,000 to 2 lakh folk artistes and all the departments have been instructed to invite them for programmes. “Joydeb Mela in Kenduli is attracting people from all over the world and more and more people are listening to Baul music now. Baul singers are natural artistes. Without any formal training they sing perfectly and their renditions touch our hearts,” she said. Banerjee said major development has taken place in Birbhum district in the past seven years. Vast areas surrounding Tarapith Temple have been given a new look and more bridges are coming up which will improve communication. She said despite loan repayment worth Rs 48,000 crore, the state government has prepared schemes for all sections of people. More than 8 crore people are being given rice at Rs 2 per kilogram and the state government is giving a huge subsidy for the project. Kanyashree has helped girls carry on with their studies up to the post-graduate level. “We have made plans for everyone and we are proud of our youths who are the future of our country,” Banerjee said.
Dark red onions, known as the richest source of dietary flavonoids, may help fight off cancer of the colon and breast, a researchers has suggested.”We found that onions are excellent at killing cancer cells,” said Abdulmonem Murayyan, doctoral student at the University of Guelph in Ontario, Canada.”Onions activate pathways that encourage cancer cells to undergo cell death. They promote an unfavourable environment for cancer cells and disrupt communication between cancer cells, which inhibits growth,” Murayyan added. Also Read – Add new books to your shelfThe findings, published recently in the journal Food Research International, revealed that red onions contain high levels of quercetin — a plant polyphenol from the flavonoid group, found in many fruits, vegetables, leaves, and grains — and include benefits such as lowering inflammation and fighting allergies, among others. Further, red onions were also found to have high amounts of anthocyanin, which enriches the scavenging properties of quercetin molecules. Also Read – Over 2 hours screen time daily will make your kids impulsive”Anthocyanin is instrumental in providing colour to fruits and vegetables so it makes sense that the red onions, which are darkest in colour, would have the most cancer-fighting power,” said Murayyan.In the first study, to examine how effective onions are at killing cancer cells, researchers have found that not all onions are created equal.The team tested five onion types grown in Ontario and discovered that the Ruby Ring onion variety — that has hard, firm, tall globe-shaped bulbs with dark red colour features — came out on top. When cells of the colon and breast cancer were placed in direct contact with quercetin extracted from the five different onion varieties, the team found them effective at killing the cancerous cells.”The next step will be to test the vegetable’s cancer-fighting powers in human trials,” said Murayyan.While currently this superfood can be included in salads and on burgers as a preventative measure, researchers expect onion extract will eventually be added to food products such as juice or baked goods and be sold in pill form as a type of natural cancer treatment.