Ancient Neutrinos Could Put String Theory and Quantum Loop Gravity to the Test 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. Some of the physicists who made early contributions to quantum mechanics (left to right, top row first): Neils Bohr, Albert Einstein, Max Planck, Wolfgang Pauli, Werner Heisenberg [Credit: Deutsches Bundesarchiv (German Federal Archive), Bild183-R57262], and Erwin Schrödinger. In a recent paper published in the European Journal of Physics, Marin has written a short history, based on a longer analysis, of the mysticism controversy in the early quantum physics community. As Marin emphasizes, the controversy began in Germany in the 1920s among physicists in reaction to the new theory of quantum mechanics, but was much different than debates on similar issues today. At the turn of the last century, science and religion were not divided as they are today, and some scientists of the time were particularly inspired by Eastern mysticism. In his analysis, Marin lays out each player’s role and perspective in the controversy, and argues that studying the original interpretations of quantum mechanics can help scientists better understand the theory, and could also be important for the public in general.“Becoming aware of this subject would help general audiences realize that there are many other alternatives besides the ones offered by the disjunction between science and religion,” Marin told PhysOrg.com. “Science vs. religion is a very recent forced choice that the founders of quantum mechanics would have never recognized, much less accepted.”Mind MattersThe controversy boils down to the age-old question of the nature of reality. As Einstein (a firm realist) once asked, does the moon exist only when looked at? Although such a viewpoint seems unlikely in our everyday lives, in quantum mechanics, physicists’ observations can sometimes affect what they’re observing on a quantum scale. As the famous Copenhagen interpretation of quantum mechanics argues, we cannot speak about an objective reality other than that which is revealed through measurement and observation.As Marin explains, the debate of consciousness in quantum theory began around 1927 when Einstein accused Neils Bohr of introducing a mysticism incompatible with science. Bohr denied the accusation and blamed it on Einstein misunderstanding him when he said that humans are both actors and observers in the world. Yet while Bohr believed that quantum processes occurred without the need for observers, he also sympathized with the idea that an extension of quantum theory might help in understanding consciousness. Einstein, for his part, adamantly opposed any subjectivity in science. He disagreed with Bohr’s view that it is unscientific to inquire whether or not Schrödinger’s cat in a box is alive or dead before an observation is made. Einstein devoted much of his later life to searching for elements of reality to make quantum mechanics a theory based on realism. For instance, the EPR paradox (Einstein-Podolsky-Rosen paradox) thought experiment in 1935 attempted to restore realism and causality to the theory.On the other hand, Wolfgang Pauli truly did harbor some of the views that Einstein accused Bohr of. Pauli favored a hypothesis of “lucid mysticism,” a synthesis between rationality and religion. He speculated that quantum theory could unify the psychological/scientific and philosophical/mystical approaches to consciousness. Pauli’s perspective was influenced by the philosopher Arthur Schopenhauer, whose views on reality were in turn influenced by Eastern religions. Still other physicists had different views. Marin argues that Max Planck, an adherent of Christianity, framed the controversy as the objectivity of science and Christianity against the mysticism of Schopenhauer and his popularization of Buddhism and Hinduism. Planck considered religion (Christianity) and science compatible based on his opinion that they are both based on objectivity but refer to distinct facets of reality. Meanwhile, Paul Dirac rejected any kind of religious vocabulary, arguing that “religion is a jumble of false assertions with no basis in reality.” The mysticism controversy also expanded into the public realm, starting in 1929 with first astrophysicist Arthur Eddington’s popular book The Nature of the Physical World. Although the book distorted many concepts, his defense of mysticism caught the attention of the international media. (Eddington was most famous for confirming Einstein’s theory of relativity by measuring an eclipse, which catapulted Einstein into fame.)In the next few years Werner Heisenberg and Erwin Schrödinger leaned toward the side of mysticism, irritating Einstein and Planck. For others, the choice was not clear cut. Marin argues that the mathematician John Von Neumann intentionally used ambiguous terms when discussing the philosophy of quantum equations, meaning he could fit on either side. “He was a genius at linguistic innovation and came up with German terms that could support many different interpretations,” Marin said.In 1958, Schrödinger, inspired by Schopenhauer from youth, published his lectures Mind and Matter. Here he argued that there is a difference between measuring instruments and human observation: a thermometer’s registration cannot be considered an act of observation, as it contains no meaning in itself. Thus, consciousness is needed to make physical reality meaningful. As Schrödinger concluded, “Some of you, I am sure, will call this mysticism. So with all due acknowledgement to the fact that physical theory is at all times relative, in that it depends on certain basic assumptions, we may, or so I believe, assert that physical theory in its present stage strongly suggests the indestructibility of Mind by Time.”Cultural ReflectionsAs Marin notes, Schrödinger’s lectures mark the last of a generation that lived with the mysticism controversy. As Marin explains, quantum mechanics up to World War II existed in a predominantly German context, and this culture helped to form the mystical zeitgeist of the time. The controversy died in the second half of the century, when the physics culture switched to Anglo-American. Most contemporary physicists are, like Einstein, realists, and do not believe that consciousness has a role in quantum theory. The dominant modern view is that an observation does not cause an atom to exist in the observed position, but that the observer finds the location of that atom. As Marin has shown, the mysticism controversy in quantum mechanics did not involve just a few physicists and mystics (as it seems to today), but at one time it attracted the physics community at large. Some of the ideas have since resurfaced, such as in Eugene Wigner’s 1961 paper on the subject, which inspired popular books such as The Tao of Physics and The Dancing Wu Li Masters, which seek to connect quantum physics to Eastern mysticism for a new generation, along with the recent film What the Bleep Do We Know?“But here it was scientists vs. non-scientists,” Marin explained. “Today it is seen as science vs. religion, but at the time of the foundation of quantum mechanics it was not. There were religious physicists on both sides of the controversy. Most of the important physicists held what we could call today religious beliefs, whether Western or Eastern. When we speak today of the ‘two cultures,’ sciences and humanities, we are referring to the famous early ‘50s lecture by C.P. Snow, in Britain, lamenting the division. German thinkers of the previous decades were barely into that phase of discipline specialization. At the turn of the century, mathematics and physics were still distinguishing themselves from the ‘natural philosophy’ that gave birth to them.”Marin hopes that scientists today might gain a new perspective on their research by considering how the founders of quantum mechanics viewed the theory.“Whenever I read scientific articles citing the classic equations conceived by German scientists, it seems to me they could have been improved by researching how the scientists themselves interpreted their own equations,” Marin said. “Among contemporary quantum field theories, the important gauge theories are indebted to the work of [Hermann] Weyl and Pauli. Yet many physicists today would be shocked if they learned how Weyl and Pauli understood the concept ‘field’ when they wrote their classic articles. They were both immersed in mysticism, searching for a way to unify mind and physics. Weyl published a lecture where he concluded by favoring the Christian-mathematical mysticism of Nicholas of Cusa. Moreover, Pauli’s published article on Kepler presents him as part of the Western mystical tradition I study. “For those who do not favor the Copenhagen interpretation and prefer the alternative proposed by David Bohm, I would suggest reading Bohm’s many published dialogues on the topic of Eastern mysticism,” he added. “Eddington and Schrödinger, like many today, joined forces to find a quantum gravity theory. Did their shared mysticism have a role to play in whatever insights they gained or mistakes they made? I do not know, but I think it’s important to find out.” More information: Juan Miguel Marin. “’Mysticism’ in quantum mechanics: the forgotten controversy.” European Journal of Physics. 30 (2009) 807-822.Copyright 2009 PhysOrg.com.All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Does mysticism have a place in quantum mechanics today, or is the idea that the mind plays a role in creating reality best left to philosophical meditations? Harvard historian Juan Miguel Marin argues the former – not because physicists today should account for consciousness in their research, but because knowing the early history of the philosophical ideas in quantum mechanics is essential for understanding the theory on a fundamental level. Explore further Citation: Quantum Mysticism: Gone but Not Forgotten (2009, June 8) retrieved 18 August 2019 from https://phys.org/news/2009-06-quantum-mysticism-forgotten.html
Hiroo Iwata, a professor at the University of Tsukuba, created the Robot Tiles. Each robot tile is covered with Kuralon EC, a touch-sensitive conductive fabric that detects pressure from the user’s feet in order to predict the position of their next step. Ultrasonic sensors transmit the position and orientation of each tile back to a central computer that instructs the tiles where to go next.As the video [in Japanese] shows, users have to walk pretty slowly across the tiles in order to give them enough time to get into position. Although these Robot Tiles don’t seem to have any obvious applications, Iwata hopes they could be useful for creating an infinite walking surface for virtual reality applications. Citation: Robot Floor Tiles Move Beneath Your Feet (2009, September 22) retrieved 18 August 2019 from https://phys.org/news/2009-09-robot-floor-tiles-beneath-feet.html via: Technabob.com© 2009 PhysOrg.com (PhysOrg.com) — In a stroke of odd creativity, Japanese researchers have created robotic blocks that automatically detect where you’re walking and position themselves in front of you before you take your next step. As a system, the blocks create an infinite walking surface, acting somewhat like moving stones as you cross an invisible creek. 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 The Robot Tiles provide an infinite walkway that might have applications in virtual reality. Credit: Hiroo Iwata. Security Alert: Beware of SMS Messages That Can Take Control of Your Phone
Schematic view of an SFG memory cell. A pn junction diode between the FG and D makes the FG semi-floating. The device’s symbolic representation is also shown. Credit: Science 9 August 2013: Vol. 341 no. 6146 pp. 640-643 DOI: 10.1126/science.1240961 More information: A Semi-Floating Gate Transistor for Low-Voltage Ultrafast Memory and Sensing Operation, Science 9 August 2013: Vol. 341 no. 6146 pp. 640-643 DOI: 10.1126/science.1240961ABSTRACTAs the semiconductor devices of integrated circuits approach the physical limitations of scaling, alternative transistor and memory designs are needed to achieve improvements in speed, density, and power consumption. We report on a transistor that uses an embedded tunneling field-effect transistor for charging and discharging the semi-floating gate. This transistor operates at low voltages (?2.0 volts), with a large threshold voltage window of 3.1 volts, and can achieve ultra–high-speed writing operations (on time scales of ~1 nanosecond). A linear dependence of drain current on light intensity was observed when the transistor was exposed to light, so possible applications include image sensing with high density and performance. © 2013 Phys.org Most modern computers are run with either metal-oxide-semiconductor field-effect transistors (MOSFETs) or a variation of them called floating-gate (FG) MOSFETs. Such transistors are now reaching their physical limit as far as how thin they can be—just a few atoms thick. For that reason, researchers have been looking for other ways to get more bang for their buck. In this new effort, the researchers turned to TFETs, which use quantum tunneling to move electrons through very thin material.TFETs have traditionally been used in very low power devices. In this endeavor, they researchers created a TFET that could be used to control the electrodes that monitor the flow of electricity into a MOSFET—in this case, the floating-gate variety (it has an additional electrode gate that allows a charge to be retained). The idea is that if the gate could be made to open and close faster, the transistor as a whole would operate faster. Current chips require a build-up of charge before the gate can be opened or closed—which requires time. TFETs, because they require less power, don’t take as long to do their work, thus embedding one in a floating gate-MOSFET would alleviate the necessity of power buildup prior to gate changes, allowing for quicker opening and closing. That’s exactly what the team in China has done. Testing thus far has shown MOSFETs with embedded TFETs have improved transistor speeds as well as reduced power requirements.The team reports that because of the way their TFETs are constructed, embedding them in current model MOSFETs should not require reconfiguration or the use of any new materials. This means that the new TFET technology could be put into use almost immediately, bumping up the speed of computers and hand held devices while lessening the amount of energy used, resulting in longer battery life. Citation: Researchers speed up transistors by embedding tunneling field-effect transistor (2013, August 9) retrieved 18 August 2019 from https://phys.org/news/2013-08-transistors-embedding-tunneling-field-effect-transistor.html (Phys.org) —Researchers at Fudan University in China have discovered a way to speed up traditional computer transistors by embedding tunneling field-effect transistors (TFETs) in them. In their paper published in the journal Science, the team describes how embedding TFETs in such transistors allows for them to be run with less power, which in turn causes them to run faster. Journal information: Science New design reduces the areal footprint of nanowire transistors by a factor of two 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
More information: Chen, L., Mullen, G. E., Le Roch, M., Cassity, C. G., Gouault, N., Fadamiro, H. Y., Barletta, R. E., O’Brien, R. A., Sykora, R. E., Stenson, A. C., West, K. N., Horne, H. E., Hendrich, J. M., Xiang, K. R. and Davis, J. H. (2014), On the Formation of a Protic Ionic Liquid in Nature. Angew. Chem. Int. Ed.. doi: 10.1002/anie.201404402AbstractThe practical utility of ionic liquids (ILs) makes the absence (heretofore) of reported examples from nature quite puzzling, given the facility with which nature produces many other types of exotic but utilitarian substances. In that vein, we report here the identification and characterization of a naturally occurring protic IL. It can be formed during confrontations between the ants S. invicta and N. fulva. After being sprayed with alkaloid-based S. invicta venom, N. fulva detoxifies by grooming with its own venom, formic acid. The mixture is a viscous liquid manifestly different from either of the constituents. Further, we find that the change results as a consequence of formic acid protonation of the N centers of the S. invicta venom alkaloids. The resulting mixed-cation ammonium formate milieu has properties consistent with its classification as a protic IL. Explore further (Phys.org) —A large team of researchers with members from the U.S., China and France has found in studying the behavior of two types of invasive ant species in southern parts of the U.S., that ant venom is mixed when the two interact causing the creation of an ionic liquid material—the first known instance of such a material occurring naturally. In their paper published in Angewandte Chemie International, the team describes how the two species of ants interact and how the liquid material comes about. Citation: Researchers discover ant rivals mix venom creating first instance of naturally occurring ionic liquid (2014, August 4) retrieved 18 August 2019 from https://phys.org/news/2014-08-ant-rivals-venom-instance-naturally.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. When fire ants made their way into the U.S. several years ago it generated a lot of news, the name alone was enough to scare people unaccustomed to such a ferocious ant species. More recently, people who have come to accept the fire ants have learned that a new type of invasive ant (also from South America) has entered the area—tawny crazy ants. And they come with both good and bad news. The good news is they are displacing fire ants. The bad news is they’re destructive and their populations swell rapidly. In this new effort the researchers have uncovered how it is that the tiny ants are able to overcome fire ants—when sprayed with fire ant venom, they cover themselves with their own venom rendering the fire ant venom harmless. But in so doing, they create a new type of thick material, an ionic liquid.Ionic liquids are by definition, salt based with low melting points. Scientists have created a large number of such liquids over the years to serve a variety of purposes—they’re used in batteries, solvents, sealants and electrolytes. The discovery by the researchers of an ionic liquid created in nature is the first that has been seen however, and thus it’s generated considerable excitement in the chemistry community.In studying the two ant species, the researchers found that when specimens encounter one another, the fire ant sprays the tawny crazy ant with venom, a move that kills many other types of insects. Instead of succumbing, the crazy ants immediately groom themselves with their own venom, rendering the fire ant venom harmless. Interestingly, another team of researchers also discovered the self-saving maneuver by the crazy ants—as part of an experiment, they found that if they prevented the crazy ants from grooming themselves, 48 percent of them died after being sprayed with fire ant venom. When allowed to groom, on the other hand, 98 percent survived. They’ve published their research in Science Express. Micrographs of evaporates of alkaloid isolate (a) and fire ant venom (b) taken at a magnification of 50X. Credit: Angew. Chem. Int. Ed.. doi: 10.1002/anie.201404402 Crazy ants dominate fire ants by neutralizing their venom © 2014 Phys.org , Angewandte Chemie International Edition Journal information: Science Express
Journal information: Biology Letters (Phys.org)—A pair of researchers at Aarhus University in Denmark has found evidence that suggests male nursery web spiders offer potential female mates silk covered insect carcasses as a means of protection from being eaten. In their paper published in the journal Biology Letters, Søren Toft and Maria Albo describe experiments they carried out to determine the true reason behind the males offering the females gifts prior to attempting to copulate and what they found by doing so. © 2016 Phys.org Scientists have known for many years that male nursery spiders off up a gift to females prior to attempting to initiated copulation, but until now, the reason behind it has not been tested—possible theories suggested that it was meant as a means to woo the female, that it was meant to show a degree of parental investment, or more importantly, that it served as a possible shield against cannibalism.To get to the correct motive, the team collected 280 pairs of the spiders and ran them through a variety of tests in their lab. Trials were run where males were caused to appear before a female with no gift under different circumstances, such as whether the female had been allowed to eat for a period of time. Identical trials were run where the male was allowed to procure a gift before being presented to the female.In all, the researchers found that when the males showed up without a gift, they were eaten 15 percent of the time, compared to just 3.6 percent of the time for gift-bearing males, and it did not matter how hungry the female was. In actuality, the research pair report, only one male spider that showed up with a gift was eaten, and that was after the two had finished copulating. The researchers also noted that males that showed up with a gift tended to be granted longer access times during copulation than non-gift bearing males, which resulted in more sperm being delivered and a greater chance of producing offspring. Females, they note, mate multiple times, storing up the sperm that is delivered and then using it to fertilize eggs once they are ready. Explore further More information: The shield effect: nuptial gifts protect males against pre-copulatory sexual cannibalism, Biology Letters, Published 18 May 2016.DOI: 10.1098/rsbl.2015.1082 , http://rsbl.royalsocietypublishing.org/content/12/5/20151082AbstractSeveral not mutually exclusive functions have been ascribed to nuptial gifts across different taxa. Although the idea that a nuptial prey gift may protect the male from pre-copulatory sexual cannibalism is attractive, it has previously been considered of no importance based on indirect evidence and rejected by experimental tests. We reinvestigated whether nuptial gifts may function as a shield against female attacks during mating encounters in the spider Pisaura mirabilis and whether female hunger influences the likelihood of cannibalistic attacks. The results showed that pre-copulatory sexual cannibalism was enhanced when males courted without a gift and this was independent of female hunger. We propose that the nuptial gift trait has evolved partly as a counteradaptation to female aggression in this spider species. Female spiders prefer the sperm of gift-bearing males Nursery web spider (Pisaura mirabilis). Female carrying egg sack. Credit: Charlesjsharp/Wikipedia/CC BY-SA 4.0 Citation: Study shows nursery web spiders offer gift to potential mates to prevent being eaten (2016, May 19) retrieved 18 August 2019 from https://phys.org/news/2016-05-nursery-web-spiders-gift-potential.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.
Gut bacteria from a worm can degrade plastic Journal information: Science Advances 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 More information: X. Jia et al. Efficient and selective degradation of polyethylenes into liquid fuels and waxes under mild conditions, Science Advances (2016). DOI: 10.1126/sciadv.1501591AbstractPolyethylene (PE) is the largest-volume synthetic polymer, and its chemical inertness makes its degradation by low-energy processes a challenging problem. We report a tandem catalytic cross alkane metathesis method for highly efficient degradation of polyethylenes under mild conditions. With the use of widely available, low-value, short alkanes (for example, petroleum ethers) as cross metathesis partners, different types of polyethylenes with various molecular weights undergo complete conversion into useful liquid fuels and waxes. This method shows excellent selectivity for linear alkane formation, and the degradation product distribution (liquid fuels versus waxes) can be controlled by the catalyst structure and reaction time. In addition, the catalysts are compatible with various polyolefin additives; therefore, common plastic wastes, such as postconsumer polyethylene bottles, bags, and films could be converted into valuable chemical feedstocks without any pretreatment.Press release A novel chemical process converts post-consumer polyethylene plastic bottles, bags, and films into liquid fuels and waxes. Credit: Jia et al. Science Advances (2016). DOI: 10.1126/sciadv.1501591 (Phys.org)—A combined team of researchers from the Chinese Academy of Sciences and University of California has found a way to degrade ordinary plastics in a way that allows for fuel to be created from plastic trash. In their paper published in the journal Science Advances, the team describes their technique and their hopes for scaling it up to allow for it to be used in actually reducing plastic trash. © 2016 Phys.org Citation: A new way to degrade plastics that turns them into fuel (2016, June 20) retrieved 18 August 2019 from https://phys.org/news/2016-06-degrade-plastics-fuel.html Most people know that modern life is filled with plastics, from packaging, to bags and soda bottles—the world has been inundated with them since they became a cheaper alternative to many other products. The problem is, of course, that they break down very slowly, which means they are piling up in landfills and serving as the source material in artificial island creation in our seas. Scientists have been looking for good ways to degrade plastics, particularly polyethylene, the most common kind produced, but until have not been able to find a means for doing so that is both inexpensive and scalable. In this new effort, the researchers report on successes they have achieved in the former and their hopes for the latter.The method by the team involves mixing the plastics with an organometallic catalyst, which was made by mixing readily available molecules that were then doped with metal iridium. The reaction caused the bonds holding the plastic together to weaken, allowing them to be more easily torn apart—after doing, so, the team was able to use the broken down material to create a diesel-like fuel which they claim could be used to power vehicles and other motors—they report that burning the fuel is also cleaner than burning other combustible materials.The team claims that the process is inexpensive and not very difficult, though it is still not clear if it is scalable. The ratio of plastic to catalyst is currently approximately 30 to1, which is not nearly good enough for commercial purposes. Their goal is 10,000 to 1. The team is also looking for something to use as part of the catalyst instead of iridium, because it is both difficult to get in large quantities and too expensive. The team is cautiously optimistic however that they will be able to find a way to change their technique to allow for use in commercial applications, which could mean, future energy seekers might be looking in landfills for a source material, rather than beneath our feet.
Maximum density of the HI gas (left panel) and its thickness (right panel) based on simple conversion from HI data to the Gaussian HI gas distribution using the rotation curve. Black lines show galactocentric distances, starting from 10 kpc (the lowest line) with the 1 kpc increment. Densities are in at cm−3, thicknesses are in kpc. The supershell GS242-03+37 is clearly visible on both maps. Credit: Ehlerova and Palous, 2018. More information: GS242-03+37: a lucky survivor in the galactic gravitational field, arXiv:1809.03863 [astro-ph.GA] arxiv.org/abs/1809.03863 © 2018 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. NGC 2367: Buried in the heart of a giant Supershells, also called superbubbles, are large cavities hundreds of light-years across containing hot gas atoms. The gaseous material in supershells, carved out by supernovae and stellar winds, is blown against surrounding interstellar medium as it is less dense than the medium.Discovered in 1979, GS242-03+37 is a neutral hydrogen supershell located in the outer Milky Way. It is a dominant object observed in the neutral hydrogen maps of the galaxy, and its size and position make it an excellent laboratory for astronomers studying the effects of large shells on their surroundings. Sona Ehlerova and Jan Palous from the Astronomical Institute of the Czech Academy of Sciences in Prague, Czech Republic, decided to learn more about GS242-03+37. Based on neutral hydrogen and carbon monoxide radio observations, as well as available data regarding star clusters in the area, the researchers conducted numerical simulations of the supershell’s structure, which allowed them to determine crucial parameters of this cavity.”We perform numerical simulations of the structure with the simplified hydrodynamical code RING, which uses the thin-shell approximation. The best fit is found by a comparison with the HI data, and then we compare the model with the distribution of star clusters near this supershell,” the astronomers wrote in the paper.Ehlerova and Palous found that GS242-03+37 is a relatively old structure when compared to other supershells. They estimate that has an age of at least 80 million years, most likely around 120 million years. According to the researchers, GS242-03+37 could survive so long in the galaxy because it is luckily placed very near the corotation radius of the spiral structure and therefore is not disturbed by the passage of the spiral arms, which could destroy the shell.The findings detailed in the paper also put the current status of GS242-03+37 into question. The researcher calculated that the structure is not as energetic as was once thought. Therefore, it may not be a supershell in the strict “energetic” definition.”Given all the uncertainties and approximations, we still refer to GS242-03+37 as a supershell, even though the basic model suggests its energy is lower than the minimum value of the energy of the supershell,” the paper reads.The study also suggests that there is a correlation between GS242-03+37 and the distribution of young (less than 120 million years old) star clusters. The authors of the paper found that young clusters tend to be preferentially located in walls of the supershell. Citation: Researchers study a neutral hydrogen supershell in the Milky Way (2018, September 24) retrieved 18 August 2019 from https://phys.org/news/2018-09-neutral-hydrogen-supershell-milky.html A duo of researchers from the Czech Republic has performed a study of the neutral hydrogen supershell known as GS242-03+37, a large structure in the Milky Way galaxy. The research, presented in a paper published September 11 on arXiv.org, provides insights into the nature of this supershell and into its interactions with surroundings. Explore further
© 2019 Science X Network Upper panel: Fit of the effective temperature to the first three Balmer lines (labeled) in the MIKE high-resolution spectrum, compared to models at the preferred Teff = 4850 K. The lines are shown on a velocity scale centred on each line, and have been offset vertically. The grey shaded blocks represent the wavelength ranges used in the χ2 minimisation. Middle panel: Fit of the surface gravity to the WiFeS medium-resolution spectrophotometry, with a zoomed inset showing the Balmer jump region, at the preferred log g = 2.0. Lower panel: Example fits to lines of Fe and Mg in the MIKE high-resolution spectrum. In all panels additional models illustrate the sensitivity, and the legend lists the models as shown from top to bottom. Credit: Nordlander et al., 2019. An international team of astronomers has detected a new ultra metal-poor star with the lowest ever measured abundance of iron. Designated SMSS J160540.18−144323.1, the newly found object is the most iron-deficient star for which iron has been detected. The finding is presented in a paper published April 16 on the arXiv pre-print repository. Explore further Astronomers identify a mega metal-poor dwarf star Metal-poor stars are rare objects as only few stars with iron abundances [Fe/H] below –5 have been discovered so far. Currently, SMSS J0313–6708, with metallicity below –7.3, is the most iron-poor star known to date. However, the most iron-poor star where iron has actually been detected is HE 1327−2326 with metallicity at a level of −5.7.Astronomers are interested in expanding the still short list of metal-poor stars as such objects have the potential to improve our knowledge of the chemical evolution of the universe. The early evolution of the universe is believed to be dependent on the properties of the first generation of metal-free stars.Searching for such stars using the SkyMapper telescope in Australia and spectrographs on other ground-based telescopes, a group of astronomers led by Thomas Nordlander of Australian National University, has identified a new addition to the list of stars with extremely low metallicities. The observations found that the star SMSS J160540.18−144323.1 (SMSS 1605−1443 for short), located in the Milky Way’s halo, most likely some 36,000 light years away, has an ultra low abundance of iron.”We report the discovery of SMSS J160540.18−144323.1, a new ultra-metal poor halo star discovered with the SkyMapper telescope,” the researchers wrote in the paper.The research found that SMSS 1605−1443 is a red giant branch star with an effective temperature of about 4,850 K, and has a remarkably low abundances of heavier elements, including an extremely low abundance of iron at a level of -6.2.While chemical abundances of other elements of SMSS 1605−1443 turned out to be compatible with alpha-enhanced chemical composition typical of halo stars, the studied object showcases strong carbon enhancement. This, according to the study, suggests an enrichment from a Population III (the first generation of metal-free stars) mixing-and-fallback supernova. “Population III stars exploding as fallback supernovae may explain both the strong carbon enhancement and the apparent lack of enhancement of odd-Z and neutron-capture element abundances,” the astronomers noted.In concluding remarks, the researchers underlined that SMSS 1605−1443 has the lowest metallicity among the stars for which iron has been detected, exhibits carbon overabundance, and that it does not show strong enhancement nor a strong abundance trend among elements heavier than carbon. Further observations of this star, studying higher-quality spectra, could deliver more detailed chemical analysis, what in result could provide more hints into the nature of its Population III progenitor star. 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: New ultra metal-poor star discovered (2019, April 25) retrieved 18 August 2019 from https://phys.org/news/2019-04-ultra-metal-poor-star.html More information: T. Nordlander et al. The lowest detected stellar Fe abundance: The halo star SMSS J160540.18-144323.1. arXiv:1904.07471 [astro-ph.SR]. arxiv.org/abs/1904.07471
Auction House and gallery Art Bull is exhibiting ‘The Museum collection IV’, a showcase of the rare, museum quality works by young artists along with the masters that provide the artists with wider audiences by showcasing their artworks in this forum at an early stage in their careers to help them get better presence and visibility in the art hemisphere.Art Bull focuses on the areas in the Indian contemporary art scene that have not been explored by the existing auction houses. With a clear vision and target in place, Art Bull intends to identify and promote young talents from all over India. As of date there are many auction houses promoting and showcasing the Masters and established artistes. Also Read – ‘Playing Jojo was emotionally exhausting’The participating artists are – Anindita Bhattacharya, A. Ramachandran, Abanindranath Tagore, Akbar Padamsee, Arpita Singh, B. Prabha, Bikash Bhattacharjee, Chintamoni Kar, Francis Newton Souza, Gaganendranath Tagore, George Keyt, Gopal Ghose, Hemendranath Majumdar, Jagdish Swaminathan, Jamini Roy, K H Ara, K.S. Radhakrishnan, Kalighat Painting, Krishen Khanna, Kshitindranath Majumdar, Maqbool Fida Husain, Nandalal Bose, Nikhil Biswas, Paresh Maity, Rabindranath Tagore, Rajesh Kumar Sharma, Rameshwar Broota, Satish Sinha, Sayed Haider Raza, Somnath Hore, Sudhir Khastagir, Sunil Das, Vinita Dasgupta, Waswo X Waswo and more. Also Read – Leslie doing new comedy special with NetflixArt Bull has conducted three auctions and the outlook is optimistic. Art Bull’s endeavour would be to continue to support emerging artists and those who are on the verge of establishing themselves as contemporary artists. Such auctions shall set the benchmark on a global platform for these artists who will invariably be the future of the art world. We would also help advocate folk and tribal artists of India that have begun to carve out a niche market for them in the art field.
His collection which will be exhibited from 24 March showcases the journey of Guru Gobind Singh.Chitrak completely submerges himself into his work. He has been researching on Guru Gobind Singh intensively for over five years. Incidentally, the exhibition coincides with Hola Mohalla, a tradition established by Guru Gobind Singh, which also happens to fall in the month of March. Behind every piece of his creation, are numerous sketches, thorough research, inspiring music and true emotion. Also Read – ‘Playing Jojo was emotionally exhausting’In 1979, AS Chitrak illustrated a comic series for Dus Guru Sahebaan. These illustrations led him to research further into Sikhism and its philosophy as a belief and not as a religion. He started listening to Gurbaani Kirtan every evening and reading every book written on Sikhism at that time.One day, while sipping tea on the terrace of his studio, he noticed a falcon sitting on the water tank, which ritually visited for the next one week. The falcon is said to be a symbol of the 10th master, Guru Gobind Singh, one with sharp vision and focus. It was the ultimate sign of motivation for Chitrak and thereon, he decided to absorb himself wholeheartedly into his next endeavor Mera Gobind.Chitrak says, ‘My life-long interest in mythology has given me energy to recreate myths and legends in a pictorial form. I plan to continue to paint mythology for a long time to come as I consider it as an infinite subject and one which is very close to my heart.’WHEN: 24 to 30 MarchWHERE: AIFACS, 1 Rafi Marg