Month: August 2019

first_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. (PhysOrg.com) — Astronomers are making plans to create a galaxy-sized observatory to look for gravitational waves. The project is part of a joint effort with astronomers from Australia and Europe, who also aim to try to detect gravitational waves. Astronomers are making plans to create a galaxy-sized observatory to look for gravitational waves. The project is part of a joint effort with astronomers from Australia and Europe, who also aim to try to detect gravitational waves.Einstein’s general theory of relativity predicts the existence of gravitational waves, which are usually described as ripples in space-time produced by masses, rather as a boat produces waves in water as it travels. Gravitational waves pass through matter and their strength weakens as they travel away from their source. The effect of the waves is to cause incredibly tiny fluctuations in the distance between the observer and the source.Gravitational waves have not yet been detected directly in practice (although they have been shown to exist by indirect means). It should theoretically be possible to detect them through minute disturbances in the time that light or radio waves take to travel from the source in space to an observer.The new project has been proposed by a consortium of astronomers known as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). The proposal is to study the radio waves from pulsars to identify these disturbances, which should be detectable as fluctuations in the times of arrival of the radio pulses. In effect, the pulsars seem to shimmer as the waves wash over them. They described their proposal in a submission by F. Jenet et al. to the Astro2010 Program Prioritization Panel on Particle Astrophysics and Gravitation earlier this month.At present, a precision of <100 ns in timing is achieved for only the most measured pulsars, but within the next decade or so astronomers believe improvements in instruments and reductions in signal-noise ratios, along with advancements such as the square kilometer array to be built in Australia or South Africa, could mean they would be able to study a 'pulsar timing array'ť (PTA) consisting of about 100 pulsars, with a timing precision of <100 ns for each pulsar in the network.NANOGrav proposes that constant observation of such a PTA would enable them to observe gravitational waves in the nanohertz to microhertz band, as well as other phenomena such as supermassive black holes and radiation relics from phenomena originating in the early stages of the universe's evolution, such as inflation and cosmic strings and superstrings.The array of pulsars would in effect form a galactic-sized observatory, which would be the most revolutionary advance in astronomy since Galileo's time. More information: • arxiv.org/abs/0909.1058• www.nanograv.org/via Technology Review© 2009 PhysOrg.com Scientists aim to unlock gravitational wave mysteries Artist's impression of a gravitational wave. Image: NANOGRAV Explore further Citation: Galaxy-Sized Observatory for Gravitational Waves (2009, September 17) retrieved 18 August 2019 from https://phys.org/news/2009-09-galaxy-sized-observatory-gravitational.htmllast_img read more

first_img Wake cloaking simulated in lab – objects move through water without leaving a trace © 2010 PhysOrg.com More information: arxiv.org/abs/1107.1647 Explore further Citation: Researchers create “antimagnet” cloaking device (2011, August 5) retrieved 18 August 2019 from https://phys.org/news/2011-08-antimagnet-cloaking-device.htmlcenter_img Alvaro Sanchez and his colleagues at Universitat Autňnoma de Barcelona have modeled on a computer, a multi-layered containment vessel comprised of different types of metamaterials (materials not found in nature that are created with specific electromagnet properties) that they say should be relatively easy to create in the real world. Their research builds on the work of John Pendry who in 2008, first proposed a method of cloaking a magnetized object by using materials with permeability in one direction less than one, and another that was perpendicular to it.In the new model, the first layer would be made of a superconducting layer of magnetic material with a permittivity (amount of resistance in an electric field) of zero. The middle layer would be an isotropic ferromagnetic material with constant permeability (degree of magnetism that a material obtains) and the outer layer would be a material with an anisotropic (property of being directionally dependent) constant in all directions.The result would be a layered coating that would conceal the magnetism of an object inside the cloak from the outside world, while simultaneously preventing any of the magnetism from leaking out.The research team hasn’t yet attempted to build their antimagnet yet, but say in deploying their computer model the device was able to hide almost all of the magnetism going on inside and didn’t leak. They believe if such a device can be built in the real world it would be useful for such applications as creating shields for people with pace-makers or cochlear implants, allowing them to be tested with MRI’s and other magnetic based equipment.The team also notes in their paper that while their model was small and cylindrical, they believe if real-world devices were built, they could be made in virtually any geometric shape.Via PhysicsWorld In what seems like one new cloaking device being discovered after another, researchers in Spain have modeled a device that they say can prevent magnetism from leaking out of a containment container and also prevent it from being detected by an outside magnetic device. Publishing their results on arXiv, the team calls their proposed creation an antimagnet, rather than a cloaking device. 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

first_img More information: L. J. MENDIS WICKRAMASINGHE, DULAN RANGA VIDANAPATHIRANA & NETHU WICKRAMASINGHE (Sri Lanka): Back from the dead: The world’s rarest toad Adenomus kandianus rediscovered in Sri Lanka, Zootaxa, 3347: 63–68. http://www.mapress.com/zootaxa/list/2012/3347.html (can be accessed here)AbstractAdenomus kandianus Günther (1872) was previously known only from two specimens both deposited in the British Museum, the holotype BMNH1947.2.20.63, and the syntype of A. kelaarti BMNH1947.2.20.62. The only record of A. kandianus since the initial description in 1872 was by Ferguson in 1876, who mentions two specimens resembling Bufo kandianus in his collection, making A. kandianus the world’s rarest toad. The species had not been reported since, and was considered extinct. Here we report on its rediscovery. Journal information: Zootaxa Image (c) Zootaxa. © 2012 Phys.Org Explore further (Phys.org) — Researchers working for the Herpetological Foundation of Sri Lanka have obtained a specimen of the Kandyan dwarf toad (Adenomus kandianus) near a stream in a sanctuary in the island nation of Sri Lanka. Prior to its find the toad had been thought to be extinct as no reports of its existence had been published since its initial description in 1872 with further details added in 1876. The researchers describe their find in a paper published in the journal Zootaxa.center_img The team came upon the toad by accident, believing it to be a torrent when it was captured on a night expedition. The two species closely resemble one another and the team believes it’s likely that the group of toads from which the Kandyan was taken were likely a mix of both. The Kandyan can be distinguished from the torrent by its froglike webbed feet and dark warts on its back.Prior to the discovery the Kandyan had been listed on the IUCN Red List of Threatened Species as extinct, primarily because it had not been seen in over a hundred years. The research team believes its status will be changed to “Critically Endangered” once updated on the list due to the threats to its environment by logging. The found specimen was definitively identified by comparing it with two specimens held in British museums since the 1800’s.The team was in the area to perform a survey on indigenous amphibians because they say not much is known about the diversity of the populations there. The region is remote, the weather generally bad and the terrain difficult to cross, and as a result few researchers have ventured into the area to find out what sorts of animal life exists there. The Kandyan sample was in fact found back in 2009, but its existence has only come to light now due to the team publishing their paper. Sri Lanka has the highest proportion of amphibians listed as extinct by any nation with some sixty percent of those recorded at one time or another as gone forever. The research team who found the Kandyan dwarf toad suggest that more surveys in the remotest parts of the island would likely prove some of those other listings to be incorrect as well. Citation: Researchers rediscover toad thought to be extinct (2012, June 20) retrieved 18 August 2019 from https://phys.org/news/2012-06-rediscover-toad-thought-extinct.html Borneo rainbow toad seen for 1st time in 87 years 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

first_img Journal information: Nature Geoscience A team of researchers in the U.S. has built a model that appears to explain the Karakoram anomaly—where unlike other parts of the world, its mountainous glaciers are not melting. In their paper published in the journal Nature Geoscience, the team explains the factors that went into their model and why their simulation appears to explain the real world phenomenon. As most everyone knows by now, the planet is warming, and because of that, glaciers across the globe are melting, with many expected to disappear over the next century, or sooner. One exception, however, is the Karakoram, a mountain chain that runs along the borders of China, India, and Pakistan—it’s technically part of the Himalaya chain. There, scientists have discovered that not only are the glaciers not melting, they appear to be growing, continually defying predictions.To find out why glaciers in that part of the world are thriving despite a rise in global temperatures, the researchers gathered weather data dating back to 1861 on three major parts of the Himalaya chain—the southeast portion, the central portion and the Karakoram. The amount of data allowed them to create a much finer map of the area than prior efforts—down to an area of just 19 square miles.After imputing the data and running the simulations—representing weather patterns right up to 2100—the researchers found that the central and southeast part of the chain received most of its moisture from the annual monsoons. The Karakoram, in contrast, got most of its precipitation in the winter, which of course meant more snow. The team notes that their model shows that the total amount of precipitation along most of the chain is increasing as the planet heats up, during the summer months. In the Karakoram, on the other hand, there is less snowfall in the summer, but more in the winter—thus the continued growing of the glaciers. Their model suggests that the glaciers are likely to continue to persist in that part of the world, right on up to 2100—after that, it doesn’t appear likely—not if global warming continues at its current pace. © 2014 Phys.org No ice loss seen in major Himalayan glaciers: scientists More information: Nature Geoscience (2014) DOI: 10.1038/ngeo2269center_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. Credit: Wikipedia Citation: Simulation explains why Asian glaciers are not melting (2014, October 13) retrieved 18 August 2019 from https://phys.org/news/2014-10-simulation-asian-glaciers.html Explore furtherlast_img read more

first_img(Phys.org)—It was an interesting week for physics as a team of researchers found a way to extend Einstein’s spooky action to allow for its use in quantum networks, to more than two optical systems. They believe it paves the way for bigger quantum networks. Also, another team published the results of research where they were looking to answer the question, how well can information be stored from the beginning of time to its end? After taking into consideration a host of physics laws and the expansion of the universe, the team concluded that the answer appears to be, not very well. In another interesting study a team of researchers conducted the first direct measurement of gravity’s curvature—by measuring the change in the gravity gradient caused by a large mass at three locations. They believe their method will allow for an improvement in the Newtonian constant of gravity. Equally interesting was a demonstration by a team of researchers of a metasurface that can solve calculus problems as an analog computer—by illuminating it with a laser beam. The surface causes the light waves to be changed to the shape of its integral or derivative. Researchers conduct first direct measurement of gravity’s curvature Citation: Best of Last Week – Extending Einstein’s spooky action, accelerated sea level rise and city personality mismatches (2015, January 19) retrieved 18 August 2019 from https://phys.org/news/2015-01-week-einstein-spooky-action-sea.html © 2015 Phys.org Explore further In other news, a team at Harvard conducted a study that revealed that the acceleration in sea level rise has been far larger than initially thought—they found that estimates of sea level rise early in the 20th century were lower than thought, which meant that the high levels we see today came more recently, which means it is happening faster than most scientists have suspected. More optimistically, University of Waterloo scientists reported that chemists are one step closer to a new generation of electric car battery—because a new material has been found that is able to maintain a rechargeable sulfur cathode. And a team at Trinity College reported that they had found a way to produce black phosphorus in bulk—and because it is inexpensive it might pave the way for its use in commercial applications. Also, another team at MIT conducted a study that detailed a link between inflammation and cancer—now doctors have a better understanding of why people who suffer from chronic inflammation are at increased risk for some types of cancers.And finally, an international team of researchers has found that if you are tired of London, you may be living in the wrong place—or wherever else you may live—it may be all in the personality. After studying survey data gathered by the BBC, they concluded that because of their nature, and the personality of cities, towns, etc., some people might be happier if they moved somewhere else. 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

first_imgDarjeeling: The Padmaja Naidu Himalayan Naidu Zoological Park (PNHZP) also known as the Darjeeling Zoo has reasons enough to cheer up as two snow leopard cubs were born in captivity in March. “Two cubs were born to Namka and Zima on March 4. The cubs are in good health and spirit. They are now housed in a special breeding facility in Tobgay Danra,” stated Pyar Chand, Director, PNHZP.Incidentally, Zima along with another female snow leopard had been brought in from Lodz Zoo in Warsaw, Poland in the first week of October 2013 in order to introduce a fresh bloodline crucial for the conservation breeding programme. She is 8 years old. Also Read – Heavy rain hits traffic, flightsNamka, the male snow leopard arrived at the PNHZP from the Mulhouse Zoo in France on September 1, 2016. He is 4 years old.PNHZP is the pioneer zoo in India to have initiated the captive breeding programme of snow leopards. In 1986, this programme had been initiated with 4 snow leopards. At present, there are 3 males and 8 females and the 2 cubs. The sex of the cubs has not been determined yet. In order to continue healthy conservation breeding, new bloodlines have been continuously introduced over the years. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedA female snow leopard was brought in from Nurnberg Zoo in Germany in 2012, two female snow leopards from Lodz Zoo, Poland in 2013 and a male from Czech Republic in April 2016 along with two other males from France and England.The snow leopards are bred in enclosures in a special non display facility at Tobgaydanra, 14 km away from Darjeeling.In summers, the snow leopard (Panthera uncia) usually lives above the tree line on mountainous meadows and in rocky regions at an altitude of 2,700 m to 6,000 m, whilst during winters, it comes down into the forests to an altitude of around 2,000 m. Snow Leopards are mainly found in Central and South Asia. They usually lead a solitary life.The PNHZP is also the coordinating zoo for the red panda breeding programme (Project Red Panda) in India. The project was initiated in 1990. Along with this, the PNHZP also has a breeding centre for pheasant in Dowhill in Kurseong. The PNHZP was founded in 1958 and specialises in the captive breeding of endangered Himalayan species including Snow Leopard, Red Panda, Tibetan Wolf, Blue Sheep, Himalayan Tahr and Satyr Tragopan (crimson horned pheasant).The zoo also houses 3 Royal Bengal Tigers, around 30 herbivores, over a hundred birds; leopards, Himalayan bear and Himalayan wolves.last_img read more

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