Month: August 2019

Relativity Derived Without Calculus Possibly Centuries Ago

first_img Einsteinian relativity seemed to be a modern breakthrough: he had derived his theories from ideas and mathematics that were new at the time. The Lorentz transformations had just been discovered in 1895, and he derived a new velocity addition law using calculus (both of these concepts describe how observers in different reference frames perceive each other). Further, Einstein based his theories on the assumption that the speed of light, c, is constant, and used gedanken (“thought”) experiments involving light rays to reach his conclusions. Now Joel Gannett, a Senior Scientist in the Applied Research Area of Telcordia Technologies in Red Bank, New Jersey, has found that Einstein didn’t have to do the work the hard way. A researcher in optical networking technologies, Gannett has shown that the Lorentz transformations and velocity addition law can be derived without assuming the constancy of the speed of light, without thought experiments, and without calculus. In this case, Einsteinian relativity could have been discovered several centuries before Einstein.“Einsteinian Relativity is difficult to wrap your mind around,” Gannett told PhysOrg.com. “It does not help that Einstein’s seminal 1905 paper, and many discussions of the topic since, start off with the wildly counterintuitive assumption that the speed of light is constant in all inertial frames. “My work shows that the essential strangeness of Einsteinian Relativity falls out of simple, intuitive assumptions using simple math. A pre-calculus high school student could have derived Einsteinian Relativity. Admittedly, some of the math in my paper might seem beyond the high school level, but that was because I was proving continuity from a boundedness assumption. One could bypass this math by simply assuming continuity, a logical step that would probably feel comfortable to most any high schooler or 17th century scientist.”Gannett is not the first person to suggest that a simpler path to modern relativity might exist. In 2003, Palash Pal of the Saha Institute of Nuclear Physics in Calcutta, India showed that the Lorentz transformations could be derived without assuming the constancy of c and without thought experiments; in fact, scientists had noted this possibility as far back as 1910. After Einstein developed his theories of special and general relativity, in 1905 and 1916, respectively, the world of physics changed dramatically. The theories, with their groundbreaking ideas on space and time, helped lead 20th century scientists to unlock the secrets of the atom and unleash the power of nuclear energy. Galileo discovered “Galilean relativity.” He had the tools to allow him—in theory—to discover Einsteinian relativity, as well. (Original portrait of Galileo painted by Justus Sustermans in 1636.) Explore further Citation: Relativity Derived Without Calculus — Possibly Centuries Ago (2007, October 8) retrieved 18 August 2019 from https://phys.org/news/2007-10-relativity-derived-calculus-possibly.htmlcenter_img To reach his derivation, Pal invoked the ideas that spacetime is homogeneous and isotropic. Pal titled his paper “Nothing but relativity”; after reading it, Gannett has called his paper “Nothing but relativity, redux,” which is published in a recent issue of the European Journal of Physics. However, Gannett explains that his derivation actually bypasses the principle of relativity altogether—instead, he assumes the simpler idea of reciprocity. “The current paper might have been titled ‘Nothing but relativity, and not that either,’ or perhaps ‘Nothing but reciprocity,” he writes, emphasizing the point.“One of the issues I raise in my paper is, why make a heavyweight assumption such as relativity when in fact all you need for the derivation is reciprocity?” he explains. “I don’t need the fact that the laws of physics are the same for you on the speeding train and me on the platform (i.e., relativity). All I need is reciprocity.”Gannett uses the common analogy of the train to explain reciprocity: “Suppose you are on a train and I am on the platform waving goodbye. Suppose I measure your speed relative to me as 30 mph. Looking back at me, you would judge that I am moving away from you at 30 mph as well. If we both had police radar guns to measure our relative speeds with great accuracy, we would both come up with the same number (say, 29.6 mph). That’s reciprocity. In the presence of isotropy, which is one of my other key assumptions, relativity implies reciprocity.”Instead of using calculus to derive the spacetime transformations, Gannett uses two basic concepts from mathematical topology: density and continuity. Using these concepts, he demonstrates how the spacetime coordinates of one reference frame (e.g. the train) can be mapped to the spacetime coordinates of a second reference frame (e.g. the platform), accounting for the distorted lengths and times that occur at high speeds.The density concept means that any irrational number (such as the number π) can be approximated to arbitrary closeness by a rational number (those with a finite number of digits or digits that repeat). The second concept, continuity, means that a function maps “close-by” points to “close-by” points. From these concepts he derives a linear homogeneous function, or a matrix, to connect the coordinates of the two reference frames. Gannett explains that proving that spacetime is linear is a vital point to make before reaching Pal’s derivation. He also notes that Einstein had glossed over this important point in his paper on special relativity.“Einstein merely stated that homogeneity (i.e., the uniformity of space and time) clearly implied linearity,” he says. “With the level of mathematics I was applying in my paper, I could fairly easily get to the point where one could assert linearity in a mythical universe where coordinates exist only as rational numbers, and we consider only rational scalings. But since the days of Pythagoras this would not be considered adequate. Because rational numbers can approximate irrational numbers to any desired degree of accuracy, continuity provides the final logical link that lets you assert linearity of the spacetime mapping.”Finally, invoking the ideas of the cosmological principle that the universe is isotropic and reciprocal, Gannett demonstrates that four basic properties of the mapping functions directly follow. From that point, Pal’s equations finish deriving the Lorentz transformation and velocity addition law using only algebra and basic physical considerations.What if Galileo, back in the 17th century, had derived the principles of Einstein’s relativity? Would the history of science progress been different? Gannett doesn’t think so.“If Galileo had derived it, Occam’s razor [‘the law of simplicity’] would have impelled him to discard Einsteinian relativity as a needlessly complex mathematical curiosity that was not required to resolve any outstanding issues known to 17th century science,” he predicts.In Einstein’s time, things were different. Newton’s classical mechanics clashed with Maxwell’s equations of electromagnetism, which date from 1861. With the ideas in special relativity, which showed that electrodynamics obeyed relativity, Einstein replaced the old spacetime model from Newtonian mechanics and solved a major challenge of the early 20th century.Citation: Gannett, Joel W. “Nothing but relativity, redux.” European Journal of Physics, 28 (2007) 1145-1150.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. Photovoltaics from any semiconductor 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


August 31, 2019 0

Study shows rhinoceros beetle horns evolved to accommodate speciesspecific fighting styles

first_img(Phys.org) —Male rhinoceros beetles have elaborate horns, which they use when fighting for mates. The shape and number of horns differ from species to species. Erin McCullough of the University of Montana at Missoula and her colleagues have discovered that horns evolved to have shapes that best suit each species’ fighting style. The research appears in the Proceedings of the National Academy of Sciences. Journal information: Proceedings of the National Academy of Sciences Play Rotating view of the 3D horn models used in the finite element analyses. Credit: Erin L. McCullough, PNAS, doi: 10.1073/pnas.1409585111 The team predicted the cross-sectional shapes of the horns of each species, considering which shapes would maximize the ability to dislodge opponents, using that species’ style of fighting. They thought cross sections of Trypoxylus horns would be triangular, those of Golofa would be circular and those of Dynastes would be elliptical. Microcomputed tomography scans proved their predictions correct. The team suggests researchers perform further studies on the effect of horn shape on other measures of fighting performance, such as grip and stability. 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. Considered the strongest animals in the world, male rhinoceros beetles compete for females by attempting to remove their opponents from trees and shoots and throw them onto the ground. They use their horns as weapons. Horns come in a wide variety of shapes.McCullough and her team wanted to find out why so many different horn types had evolved. They did not find any evidence that females chose mates based on horn size or shape, so they hypothesized that horn shapes evolved to improve fighting ability. Previous studies on the horns and antlers of ungulates supported this hypothesis. Among ungulates, males with long horns tend to fence or wrestle, males with curved horns tend to ram and males with short, smooth horns tend to stab.To see if rhinoceros beetles also had horns suited to their particular fighting styles, the team used a type of computer modeling system, known as finite element analysis, to calculate the stresses and strains the horns would experience when used for different methods of fighting. They studied three species: Trypoxylus dichotomus, Golofa porteri, and Dynastes hercules. All of these species have differently shaped horns, which they use in different ways. Trypoxylus has pitchforked-shaped horns that it uses to pry and twist opponents off tree trunks and branches. Golofa has long, slender horns that it uses like fencing swords, lifting opponents and throwing them off balance when fighting on narrow shoots. The head and thoracic horns of Dynastes form pincers, which the beetle uses to lift and squeeze opponents, then toss them to the ground. Models showed that a species’ horns experienced the least stress and strain under conditions that mimicked species-typical fights. Citation: Study shows rhinoceros beetle horns evolved to accommodate species-specific fighting styles (2014, September 9) retrieved 18 August 2019 from https://phys.org/news/2014-09-rhinoceros-beetle-horns-evolved-accommodate.html Play Animations of the Von Mises stress distributions from finite element models of a Trypoxylus dichotomus horn loaded under vertical bending, lateral bending, and twisting. Credit: Erin L. McCullough, PNAS, doi: 10.1073/pnas.1409585111 PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen © 2014 Phys.org PausePlay% buffered00:0000:00UnmuteMuteDisable captionsEnable captionsSettingsCaptionsDisabledQuality0SpeedNormalCaptionsGo back to previous menuQualityGo back to previous menuSpeedGo back to previous menu0.5×0.75×Normal1.25×1.5×1.75×2×Exit fullscreenEnter fullscreen More information: Structural adaptations to diverse fighting styles in sexually selected weapons, Erin L. McCullough, PNAS, DOI: 10.1073/pnas.1409585111 AbstractThe shapes of sexually selected weapons differ widely among species, but the drivers of this diversity remain poorly understood. Existing explanations suggest weapon shapes reflect structural adaptations to different fighting styles, yet explicit tests of this hypothesis are lacking. We constructed finite element models of the horns of different rhinoceros beetle species to test whether functional specializations for increased performance under species-specific fighting styles could have contributed to the diversification of weapon form. We find that horns are both stronger and stiffer in response to species-typical fighting loads and that they perform more poorly under atypical fighting loads, which suggests weapons are structurally adapted to meet the functional demands of fighting. Our research establishes a critical link between weapon form and function, revealing one way male–male competition can drive the diversification of animal weapons. Researchers unlock genetic twist in differences in horn size with sheep Explore furtherlast_img read more


August 31, 2019 0

Temperature dependence and the thermal limits of embryogenesis

first_img More information: Temperature Dependence of Cell Division Timing Accounts for a Shift in the Thermal Limits of C. elegans and C. briggsae, Cell Reports, www.cell.com/cell-reports/abst … 2211-1247(15)00007-8AbstractCold-blooded animals, which cannot directly control their body temperatures, have adapted to function within specific temperature ranges that vary between species. However, little is known about what sets the limits of the viable temperature range. Here we show that the speed of the first cell division in C. elegans N2 varies with temperature according to the Arrhenius equation. However, it does so only within certain limits. Outside these limits we observe alterations in the cell cycle. Interestingly, these temperature limits also correspond to the animal’s fertile range. In C. briggsae AF16, isolated from a warmer climatic region, both the fertile range and the temperature range over which the speed of cell division follows the Arrhenius equation, are shifted toward higher temperatures. Our findings suggest that the viable range of an organism can be adapted in part to a different thermal range by adjusting the temperature tolerance of cell division. Journal information: Cell Reports XX and XO worm configurations. Credit: wormbook.org © 2015 Phys.org (Phys.org)—Raising the temperature is one easy way to get chemical reactions to speed up. This temperature dependence can be accurately described by a simple exponential relation known as the Arrhenius equation. A commonly accepted generalization of this equation is that the reaction rate tends to double for every 10 degree Celsius temperature increase. Many biological phenomena, like rates of firefly flashes or the speeds of working ants, have also been shown to follow similar kinetics. A recent paper in Cell Reports now shows that not only does the timing of cell division cycles in the early embryo follow the temperature prescription called for by Arrhenius, but that this developmental dependence is what ultimately constrains the thermal limits of the organism itself. New mechanism of inheritance could advance study of evolution, disease treatment Citation: Temperature dependence and the thermal limits of embryogenesis (2015, February 11) retrieved 18 August 2019 from https://phys.org/news/2015-02-temperature-thermal-limits-embryogenesis.html The worm c. elegans is an ideal organism to use to crack the secrets of multicellular life. Researchers are now on a first name basis with all the cells found in its developing embryo, and can track each them as they asynchronously cleave off and reform to establish various organs and planes of symmetry—much as you or I would watch an elaborately choreographed Superbowl halftime show. The authors focused their attentions on the timing of what is probably the most important division in the embryo, the first one. Specifically, they measured the interval between the time the pronuclei first meet and the onset of cytokinesis. To give some idea of the kinds of numbers we are talking about here, the authors reported a nice exponential fit from 5°C to 25°C, where cell division time correspondingly fell from 50 minutes down to 5 minutes. Above these temperatures there began to be subtle signs that all was not well in wormland. At 25°C they would start to get sterile worms, presumably because germ cell specification was disrupted at this point. Above 28°C, the precision Arrhenius sensitivity began to break down with embryos unable to establish proper symmetry. By 30°C, there would be failure to reach the first division cycle all together.The authors also looked at cell division in C. briggsae, a high-temperature-tolerant worm hailing from India. Although this lineage apparently split from C. elegans over 18 million years ago, it is almost identical in morphology and reproductive detail. The authors found there was a shift, rather than an expansion of the thermal sensitivity relation for C. briggsae. This result led them to speculate that such adaption may not require multiple independent mutations acting on specific tissue or cell types, but rather the thermal sensitivty of the whole organism is shifted in response to evolutionary pressure by some other kind of mechanism.It was found when cell cycle timing deviates from an exponential temperature relation, coordination of events that depend on the first cell division, and all subsequent development is impaired. The authors suggest that these observed temperature relations may be the key to evolving coordinated biological processes that are able to remain synchronized even as the genetic or enviromental landscape changes. They do note, however, that not all high level developmental processess (like cell division) will be expected to occur with Arrhenius kinetics. The breakdown of the nuclear envelope prior to cleavage, for example, happens earlier than would be predicted. Other kinds of events, like unfolding of proteins in response to heat stress, will be expected to happen more-or-less above some hard threshold temperature. Perhaps the best way to try and explain how different worms, and organsims, in general can control their thermal behavior (like the upper temperature limits of cell division) is through the unifying rate mechanisms of their mitochondria. We recently discussed the involvement of mitochondria—and the temperature they set through the heat and chemical energy they make available—in the specification of individual blastomeres of developing embryos. In suggesting that the maximum rate of mitochondrial activity may be a fundamental limit on the rate of cell division, the authors note that the C. briggsae worms have a comparatively lower mitochondrial membrane potential and lower levels of reactive oxygen species—an observation that squares with its slower cell cycle and increased temperature resistance.When cellular respiration is experimentally manipulated by using a technique known as RNA interference (RNAi), embryonic cell cycle turnover and progression through developmental milestones is slowed down. One reason this RNAi seems to work so well is that researchers are finding that RNA is naturally used to perform all kinds of tricks in germ cells. We mentioned above that C. elegans germline specification was found to be highly temperature sensitve. As with most animals, these cells are typically set aside after just four cell divisions. The latest research now indicates that once they are made these germ cells continue to receive instructional inputs in the form of RNA not just from researchers via injection or ingestion and subsequent migration to germ cells, but from a home grown RNA source synthesized by distant somatic cells and delivered through the network of their own nervous system.More specifically, it was found that neurons handing-off double stranded RNA to germ cells results in transgeneration gene silencing in corresponding matching sequences. Moreover, this directly heritable effect lasts at least 25 generations. In other words we now have another fine example where full-blown Lamarckian pandemonium runs wild, and the entire organism via its nervous sytem, is essentially understood as one massive antennal harvester of information capable of transducing environment to germ.Extrapolating effects like temperature dependence, or mitochondrial and RNA-based control to other kinds of creatures, will take some care. Mammals, who tend to do embryogenesis a little differently, generally don’t need to swim across entire oceans just to assure themselves of finding a place with a predictable temperature to stow their eggs. On the other hand, even if mammals routinely scuttle mobile RNAs from nerve to germ like the worm, there is no guarentee that inherited effects would escape the epigentic informational reboot that may or may not blank significant life experience gained in each generation. 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


August 31, 2019 0

Possums in Tasmania growing bolder as devils decline

first_imgBrushtail Possum in tree. Credit: Dr Jane DeGabriel (Phys.org)—A team of researchers from several universities in Australia has found that brushtail possums have begun altering their foraging habits in light of the decline of Tasmanian devils in Tasmania and other nearby islands. In their paper published in Proceedings of the Royal Society B, the team describes field studies they conducted on the islands, what they learned and why they believe an ecosystem change is coming. 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. © 2015 Phys.org Tasmanian devils are small scary-looking marsupial animals that live off of animals that they capture and kill—they are native to Tasmania and a few surrounding islands, but over the past decade their numbers have dwindled dramatically as they have been decimated by devil facial tumor disease—a contagious type of cancer. One of their prey is the brushtail possum, an arboreal animal that eats mostly eucalyptus leaves—though they do venture to the ground as often as possible to eat nuts and berries. In this new effort, the researchers wondered if the lifestyle of the possums had changed now that one of their main predators was rarely seen. To find out, they ventured to Tasmania and another island (Maria) in the vicinity that had been devil-free for thousands of years.The team set up feeders on the ground in both locales stocked with raisins, a food they know the possums like. Some of the feeders were placed close to trees, others farther away, and some of the feeders had rocks mixed in with the raisins, or openings that required a head to be inserted, preventing a possum from seeing if a predator was nearby while it munched.As expected, the researchers found that the possums had grown bolder—in places that had seen the sharpest declines, the possums were the most bold, behaving in some instances, in much the same way as possums on devil-free Maria island, wandering around on the ground as they pleased. What was surprising was how quickly the possums had adapted to the nearly sudden absence of the devils.The researchers suggest their findings offer information that might prove useful in other areas, where it is not possible to study a declining apex predator in isolation, such as Yellowstone National Park in the U.S., where park managers have been experimenting with reintroducing wolves. They also note that increased foraging by possums is likely to cause an as yet unknown impact on the local ecosystem. Citation: Possums in Tasmania growing bolder as devils decline (2015, June 17) retrieved 18 August 2019 from https://phys.org/news/2015-06-possums-tasmania-bolder-devils-decline.htmlcenter_img Journal information: Proceedings of the Royal Society B Hungry pythons mean male possums live fast and die young More information: Relaxation of risk-sensitive behaviour of prey following disease-induced decline of an apex predator, the Tasmanian devil, Proceedings of the Royal Society B, DOI: 10.1098/rspb.2015.0124AbstractApex predators structure ecosystems through lethal and non-lethal interactions with prey, and their global decline is causing loss of ecological function. Behavioural changes of prey are some of the most rapid responses to predator decline and may act as an early indicator of cascading effects. The Tasmanian devil (Sarcophilus harrisii), an apex predator, is undergoing progressive and extensive population decline, of more than 90% in long-diseased areas, caused by a novel disease. Time since local disease outbreak correlates with devil population declines and thus predation risk. We used hair traps and giving-up densities (GUDs) in food patches to test whether a major prey species of devils, the arboreal common brushtail possum (Trichosurus vulpecula), is responsive to the changing risk of predation when they forage on the ground. Possums spend more time on the ground, discover food patches faster and forage more to a lower GUD with increasing years since disease outbreak and greater devil population decline. Loss of top–down effects of devils with respect to predation risk was evident at 90% devil population decline, with possum behaviour indistinguishable from a devil-free island. Alternative predators may help to maintain risk-sensitive anti-predator behaviours in possums while devil populations remain low. Explore furtherlast_img read more


August 31, 2019 0

Best of Last Week – Renewable energy from evaporating water lefthanded kangaroos

first_imgSchematic illustration of electrically biased suspended graphene and light emission from the center of the suspended graphene. Credit: Young Duck Kim/Columbia Engineering Explore further Researchers discover first sensor of Earth’s magnetic field in an animal (Phys.org)—It was a good week for new technology as a team of researchers at Columbia University announced a way to get renewable energy from evaporating water—they have come up with two devices, one a piston-based engine that generates electricity while floating, and the other, a rotary engine that powers a tiny car. Also, another team with members from the U.S. and Korea demonstrated for the first time an on-chip visible light source using graphene—the world’s thinnest light bulb. And a team of chemists at UCLA announced that they had devised technology that could transform solar energy storage—it is a way to extend energy storage in solar cells from microseconds to weeks. © 2015 Phys.orgcenter_img 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: Best of Last Week – Renewable energy from evaporating water, left-handed kangaroos and a fasting diet that slows aging (2015, June 22) retrieved 18 August 2019 from https://phys.org/news/2015-06-week-renewable-energy-evaporating-left-handed.html It was also an interesting week for biological research as one team of researchers at the University of Texas announced that they had discovered the first sensor of Earth’s magnetic field in an animal. They found a microscopic structure in a C. elegans, a type of worm that senses the magnetic field and to modifies its behavior based on what it finds. They suspect similar structures exist in other animals such as geese that help them navigate. Also, another team found that Saharan silver ants can control electromagnetic waves over an extremely broad spectrum range—it helps them stay cool in the hot desert. And another team of researchers with members from Russia and Australia found that Kangaroos are left-handed—which came as a surprise as the marsupials do not have a neural network in their brain that connects their left and right hemispheres. The team has also shown that handedness is not unique to primates. Another team at the University of Warwick was able to show that self-awareness is not unique to mankind—they used thought experiments to figure out which capabilities any animal must have in order to mentally simulate the environment around them, and then found examples in other animals, such as rats in a maze. And a team at Monash University has found that with people, emotional brains are “physically different” to rational ones. They found actual differences in grey matter. Also a team of researchers at Rutgers University discovered a bacterium that “breathes” uranium and renders it immobile—possibly allowing for a new way to clean up radioactive waste.And finally, if you have been looking for a way to stave off the impact of Father Time, a team of researchers at USC has found that a diet that mimics fasting appears to slow aging—mice cycled on and off the diet for a period of time lost weight, got smarter and lived longer.last_img read more


August 31, 2019 0

Facebook study suggests online users reinforce their views by creating echo chambers

first_img Are you Facebook dependent? Scientists and other people have known for quite some time that many people tend to limit their exposure to news sources that offer information that goes against their own beliefs—instead, they are drawn to sources that they find agreeable and in so doing bolster their beliefs—when multiple people do the same thing and use the same sources they create what has become known as echo chambers. The researchers with this new effort have found a similar pattern in information processing by people that use the Internet—most specifically, those that use Facebook.Suspecting that Facebook users access and consume news information in ways similar to that found previously with other news outlets, the researchers accessed publicly available data via Facebook’s Graph application program interface and used it as a source of information. It provided them with data regarding user content which the researchers divided into different categories, such as conspiracy theories or science news. They also created a dataset consisting of data from what they describe as “troll pages,” which of course are the comments that people leave on other people’s pages. Both types of data were obtained for the five year span 2010 to 2014. The team then ran analysis software on the dataset to obtain pattern information.In examining their results the researchers report that they found evidence that Facebook users do indeed tend to engage in creating echo chambers, encasing themselves in environments that mesh with their own personal beliefs while rejecting other viewpoints, thereby reinforcing their own views. The researchers suggest such practices help explain such odd phenomenon as the widespread rejection of scientific evidence of global warming, or Jade Helm 15, where alarmists set off online panic by suggesting that military training exercises occurring in various parts of the U.S. last summer were a sure sign of an impending civil war. The researchers suggest that those seeking to break into echo chambers with what they believe is truthful information, find a way to reach a larger audience, rather than by knocking their way into small subgroups. They note that some have achieved some success by resorting to buying advertising space to get their message through. (Phys.org)—A team of researchers from several institutions in Italy and one in the U.S. has found evidence that suggests Internet users follow a pattern similar to that found in other media regarding how they look for and use information they find. In their paper published in Proceedings of the National Academy of Sciences, the team describes how they downloaded data from Facebook, analyzed it and found examples of echo chamber type behaviors. 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. © 2016 Phys.org Journal information: Proceedings of the National Academy of Sciences Citation: Facebook study suggests online users reinforce their views by creating echo chambers (2016, January 5) retrieved 18 August 2019 from https://phys.org/news/2016-01-facebook-online-users-views-echo.html More information: Michela Del Vicario et al. The spreading of misinformation online, Proceedings of the National Academy of Sciences (2016). DOI: 10.1073/pnas.1517441113AbstractThe wide availability of user-provided content in online social media facilitates the aggregation of people around common interests, worldviews, and narratives. However, the World Wide Web (WWW) also allows for the rapid dissemination of unsubstantiated rumors and conspiracy theories that often elicit rapid, large, but naive social responses such as the recent case of Jade Helm 15––where a simple military exercise turned out to be perceived as the beginning of a new civil war in the United States. In this work, we address the determinants governing misinformation spreading through a thorough quantitative analysis. In particular, we focus on how Facebook users consume information related to two distinct narratives: scientific and conspiracy news. We find that, although consumers of scientific and conspiracy stories present similar consumption patterns with respect to content, cascade dynamics differ. Selective exposure to content is the primary driver of content diffusion and generates the formation of homogeneous clusters, i.e., “echo chambers.” Indeed, homogeneity appears to be the primary driver for the diffusion of contents and each echo chamber has its own cascade dynamics. Finally, we introduce a data-driven percolation model mimicking rumor spreading and we show that homogeneity and polarization are the main determinants for predicting cascades’ size.last_img read more


August 31, 2019 0

Ageism A Prevalent and Insidious Health Threat

first_imgMaybe you recall another media campaign last fall intended to encourage young people’s participation in the midterm elections. In pursuit of this laudable goal, marketers invoked every negative stereotype of old people — selfish, addled, unconcerned about the future — to scare their juniors into voting. Adweek called it “comically savage.” I’d drop the “comically.” And such jabs constitute mere microaggressions compared to the forms ageism often takes: pervasive employment discrimination, biased health care, media caricatures or invisibility. When internalized by older adults themselves, ageist views can lead to poorer mental and physical health. After a bunch of us squawked about the ad on social media, the company apologized for what it called attempted humor and what I’d call ageism.center_img It happened about a year ago. I stepped off the subway and spotted an ad on the station wall for a food delivery service. It read: “When you want a whole cake to yourself because you’re turning 30, which is basically 50, which is basically dead.” “It’s an incredibly prevalent and insidious problem,” said Alana Officer, who leads the World Health Organization’s global campaign against ageism, which it defines as “stereotyping, prejudice and discrimination” based on age. “It affects not only individuals, but how we think about policies.” Read the whole story: The New York Timeslast_img read more


August 31, 2019 0

Fun and food junction

first_imgGet ready to indulge in the football fun during this FIFA World cup. The World Cup is now in its second week, preparing to enter into the final phase. So adding flavour to the fun, The Imperial brings you the football combos.  It combines the thrill and action with the delectable cuisine, all set to enthrall you. The action packed matches will be screened  in big screens to shoot your excitement to the next level with some great food that will keep you glued to the screens. Also Read – ‘Playing Jojo was emotionally exhausting’Offering you the Global gourmet has snacks combo, ideal to savour with refreshing drinks while following the heat of the matches. A special  football burger would be available with four soft beverages and with four imported beerbottles. The menu includes specialties from almost all the major Soccer regions in the world like fish and chips, Bratwurst and caramelized onions, Tortilla de patatas, Yakitori and Sushi, Barbecue pork ribs, battered onion rings, Imam Bayildi, Hummus and Pita and Panini Caprese. The unmatched taste of the combos will hook you to the screen. So head on!last_img read more


August 31, 2019 0

Anime and Manga visit India

first_imgThe first day of the convention featured some of the renowned animators, game designers, illustrators, artists and related companies from countries like Japan, Hong Kong, US, France to conduct several Master classes, Workshops, Panel discussions, Talks and Presentations.International Japanese animator Daizen Komatsuda took a session on Manga Story Board drawing; he is the key animators for many famous anime movies like, Spirited Away, Innocence, and Attack on Titans. The CEO of JI style Yoshifumi Abe also gave a presentation on his company products and the scope of Indo-Japan trade. Also Read – ‘Playing Jojo was emotionally exhausting’For hardcore gamers, PS4 gaming booth was setup to make gaming experience at its finest. The convention also featured a Cosplay booth which had a team of professional Cosplayers with whom you can click photos, get autographs and more. The Convention offered more with anime and manga quizzes, Treasure Hunt: ‘Detective Conan’, where the participants solved the riddles to find the clue and get treasure chest. The second day was commenced with the interactive session on Character Design by Chris Solarski , video game designer and illustrator. 3D animation fans got exclusive opportunity to meet Hiroaki Matsuura, the president and CEO of Sanzigan who introduced the Japanese art animation and 3D techniques. Also Read – Leslie doing new comedy special with NetflixDr. Ryan Holmberg, author and art historian conducted a talk session on Pop manga; the word of Seiichi Hayashi. He said, ‘It is a delight for me to translate old Japanese comics and the goal is to get all Indian fans interested in all different styles of Manga’. The Convention director Nitesh Rohit conducted a panel discussion on ‘the future of anime and manga business India’ and discussed about the current scenario of anime and manga business.The 3rd and the final day of Anime Convention 2014 ended with the most awaited show of the evening The Cosplay Competition. The event was judged by panel of judges including illustrators and designers from Japan , Hong Kong.This annual convention was whole new experience for the Indian audience to explore the enormous world of Anime and to inculcate new ideas and creativity in the young generation. It stands on the idea of bringing the fandom and experts under one roof to cherish Japanese pop culture and to create a business environment for Indo-Japanese collaboration.last_img read more


August 31, 2019 0

Arabul wins while in cop custody 5 Independents taste victory

first_imgKolkata: The election results at Bhangar in South 24-Parganas remained a point of discussion throughout the day, with Trinamool Congress leader Arabul Islam winning contest while in police custody, whereas five of the eight Independent candidates who had filed their nomination through WhatsApp, also won the polls.Reacting to the victory of Arabul from within police custody, Trinamool Congress supremo and Chief Minister Mamata Banerjee said: “It was not proved whether Arabul was guilty or not. But I had instructed the police to arrest him on the basis of allegations. Arabul, his son and even his wife have won from Bhangar. If people there did not have love for him (Arabul), then he would not have been able to win.” Also Read – Heavy rain hits traffic, flightsIt may be mentioned that Arabul Islam was arrested in connection with the murder of a supporter of an Independent candidate in Bhangar on May 11, three days before the polls in Bengal. It was the Chief Minister who had directed the police to arrest Arabul, as soon as allegations of the latter’s involvement in the murder surfaced.As the election results were announced, it was found that Arabul had defeated Independent candidate Shariful Islam, backed by Land and Livelihood Protection Committee, with a margin of 2,270 votes at Bhangar 2 Panchayat Samiti seat. His son Hakimul won by 1,287 votes from Polerhat 2 Gram Panchayat. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedIt may be mentioned that in Bhangar 2 Panchayat Samiti, there was no Opposition candidate in 29 out of 30 seats. The only candidate was fielded in the seat in which Arabul contested.In Polerhat 2 Gram Panchayat, there were contests in eight seats out of 16. Out of these, Independent candidates backed by Land and Livelihood Protection Committee won in five seats, much to the discomfiture of Arabul’s son Hakimul, who was the pradhan of the Gram Panchayat. These candidates had moved the Calcutta High Court, pleading acceptance of their applications filed through WhatsApp, which was allowed by the court. Following this, the State Election Commission accepted their nominations. They had alleged that they failed to appear physically to file their applications, as they were prevented from doing so by the ruling party.It may be mentioned that the Land and Livelihood Protection Committee, popularly known as Jomi Jibika Bastutantra Rokkha Committee, has been leading a stir against a power grid station at Bhangar. The place has often been on the boil since January 2017, with Arabul Islam and his supporters clashing repeatedly with the villagers participating in the agitation against land-acquisition for the power grid. Police suspect the agitation has the support of ultra-Left group Red Star, many of whose members were arrested under UAPA.last_img read more


August 31, 2019 0