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. An X-ray image of the quasar PKS 1127-145, located about 10 billion light-years from Earth. Credit: NASA. The physicists, John Webb from the University of New South Wales and his coauthors from Swinburne University of Technology and the University of Cambridge, used data from two telescopes to uncover the spatial dependence of the fine-structure constant. Using the north-facing Keck telescope in Mauna Kea, Hawaii, and the south-facing Very Large Telescope (VLT) in Paranal, Chile, the researchers observed more than 100 quasars, which are extremely luminous and distant galaxies that are powered by massive black holes at their centers.By measuring the quasar spectra, the researchers could gather data on the frequency of the electromagnetic radiation emitted by quasars at high redshifts, corresponding to a time about 10 billion years ago. During the time the light traveled through space to reach the telescopes, some of it was absorbed at specific wavelengths by very old gas clouds that today can reveal the chemical composition of the clouds. The cloud compositions could help the scientists determine the fine-structure constant in those areas of the universe at that time, since alpha is a measure of the strength of the electromagnetic force between electrically charged particles. As the coupling constant for the electromagnetic force, it is similar to the constants for the other three known fundamental forces of nature: the strong nuclear force, the weak nuclear force, and gravitational force. Among its important implications, alpha determines how strongly atoms hold on to their electrons. By combining the data from the two telescopes that look in opposite directions, the researchers found that, 10 billion years ago, alpha seems to have been larger by about one part in 100,000 in the southern direction and smaller by one part in 100,000 in the northern direction. The data for this “dipole” model of alpha has a statistical significance of about 4.1 sigma, meaning that that there is only a one in 15,000 chance that it is a random event. Play This video shows the path of light as a beam as it travels from the quasar, through an intervening galaxy and then to the Earth where we capture it with our telescopes. The inset shows the quasar spectrum as it is redshifted (due to the expansion of the universe as it travels) and as it is imprinted with the absorption signature of the intervening galaxy. • PhysOrg.com iPhone / iPad Apps• PhysOrg.com Audio Podcasts / iTunes• PhysOrg.com Android apps (new version available)• Join PhysOrg.com on Facebook!• Follow PhysOrg.com on Twitter! Explore further 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 Illustration of the dipolar variation in the fine-structure constant, alpha, across the sky, as seen by the two telescopes used in the work: the Keck telescope in Hawaii and the ESO Very Large Telescope in Chile. Copyright Dr. Julian Berengut, UNSW, 2010. May be used with appropriate attribution. Explained: Why many surveys of distant galaxies miss 90 percent of their targets At first, the data surprised Webb and his colleagues, since it seemed to contradict previous results that the scientists had published in 1999. At that time, the scientists had used the north-facing Keck telescope to find that alpha became slightly smaller the further away (and older) the quasars were. So when the scientists first looked at equally distant quasars from the southern hemisphere using the VLT, they were surprised to find the slight increase in alpha. After eliminating any possible bias, though, they realized that they were looking at hemispherical differences of alpha.While the data from just one telescope seemed to suggest that alpha varies in time, data from the two telescopes show that alpha also seems to vary in space. Such a discovery could have major implications, starting with shattering the basic assumption that physical laws are the same everywhere in the universe. The results also violate the Einstein Equivalence Principle, and suggest that the universe may be much larger than currently thought – or even infinite in size. Right now, the scientists want to confirm the results with other experimental methods, and see if the fine-structure constant could truly lead scientists to a very different understanding of our universe. (PhysOrg.com) — One of the most controversial questions in cosmology is why the fundamental constants of nature seem fine-tuned for life. One of these fundamental constants is the fine-structure constant, or alpha, which is the coupling constant for the electromagnetic force and equal to about 1/137.0359. If alpha were just 4% bigger or smaller than it is, stars wouldn’t be able to make carbon and oxygen, which would have made it impossible for life as we know it to exist. Now, results from a new study show that alpha seems to have varied a tiny bit in different directions of the universe billions of years ago, being slightly smaller in the northern hemisphere and slightly larger in the southern hemisphere. One intriguing possible implication is that the fine-structure constant is continuously varying in space, and seems fine-tuned for life in our neighborhood of the universe. Citation: Variations in fine-structure constant suggest laws of physics not the same everywhere (2010, September 6) retrieved 18 August 2019 from https://phys.org/news/2010-09-variations-fine-structure-constant-laws-physics.html More information: J. K. Webb, et al. “Evidence for spatial variation of the fine structure constant.” Submitted to Physical Review Letters. Available at arXiv:1008.3907v1 [astro-ph.CO] © 2010 PhysOrg.com
More information: code.google.com/p/flyspeck/wik … AnnouncingCompletionvia Newscientist 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. Computer generated math proof is too large for humans to check It was back in 1611 that Johannes Kepler first suggested in a paper he’d written (after corresponding with Thomas Harriot) that if you want to stack cannon balls on a ship’s deck in the most efficient way possible (a question originally posed by Sir Walter Raleigh), the best way to do it is in a pyramid shape. Cut to 1998 when Hales completed work on his written proof (which included portions that could only be verified by computer). But it was huge, as many mathematical proofs tend to be—300 pages in all that took 12 reviewers four years to verify. A 99 percent certainty rating wasn’t enough for Hales, however, so he launched the Flyspeck Project to create a means for proving the proof correct using a computer.Hales and his team used two software tools that have been created for the sole purpose of verifying proofs—HOL Light and Isabelle—they work by checking the logic of statements made in the proof. Now after eleven years of work, the team has announced that they’ve succeeded in their endeavor. Hales’ original proof has been converted to code the computer can work with and the software checkers found no discrepancies, which means the proof of the conjecture has been verified.The success by the team highlights a growing movement of using computers to verify proofs that human beings have created giving the results more credence. Computers have also been used to construct original proofs for some basic problems, which suggests that someday in the not-too-distant future, computers will be doing all the heavy work, leaving mathematicians to ponder the deeper questions regarding what the proofs represent and how they can be used in real world applications. Citation: Team announces construction of a formal computer-verified proof of the Kepler conjecture (2014, August 13) retrieved 18 August 2019 from https://phys.org/news/2014-08-team-formal-computer-verified-proof-kepler.html (Phys.org) —A team of researchers led by the man, Thomas Hales, who came up with written proof of the Kepler conjecture is now reporting that they have constructed a formal proof of the conjecture, which implies the use of a computer. The announcement was made on The Flyspeck Project page, and puts to rest any doubts about the correctness of the proof done by Hales in 1998. Explore further © 2014 Phys.org One of the diagrams from Strena Seu de Nive Sexangula, illustrating the Kepler conjecture
Explore further Observed and simulated change in global-mean surface temperature. Credit: Nature Climate Change (2014) doi:10.1038/nclimate2355 Global warming ‘pause’ since 1998 reflects natural fluctuation, study concludes © 2014 Phys.org Citation: Separate studies suggest current “pause” in global warming likely the last (2014, September 2) retrieved 18 August 2019 from https://phys.org/news/2014-09-current-global.html Most scientists agree that the current pause we are experiencing with global warming is likely due to the ocean serving as a massive heat sink (and a small amount of cooling due to volcanic eruptions). Most also agree that the time is coming soon when the oceans will stop absorbing the excess heat, ending the pause we are experiencing and allowing global temperatures to rise again.The team in Japan has found, using climate records and models, that natural variations in temperature over the past thirty years have had less of an influence on the overall warmth of the planet than in the past, suggesting, that pauses such as we are now experiencing will have less and less of an impact going forward if the atmosphere continues to heat up. More specifically, their models show that during the 1980’s natural atmospheric temperature variations accounted for roughly half of temperature changes that were seen. In the 1990’s the percentage fell to just 38 percent and then to 27 percent after the turn of the century. Heading into the future, they predict, warming due to human activities will account for more and more of the changes in temperatures, leaving less variability due to natural causes such as the one that led to the pause we are now experiencing.The team in Australia ran 31 environmental models and came to the conclusion that if greenhouse gas emissions continue at their current rate, the likelihood of another pause in global warming drops to near zero. Even worse, they suggest that the extra heat that has been pulled into the world’s oceans is likely to be released causing a speed-up of global warming. Their models show that even if there is a major volcanic event of the magnitude of Krakatau, for example, the outcome remains the same, a constant increase in global temperatures, i.e. no hiatuses or pauses along the way.Both groups suggest the catastrophic impact of global warming in the not-too-distant future as seen in their dire predictions can be averted if we act now as a global community to reduce greenhouse gas emissions. Journal information: Nature Climate Change 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. , Geophysical Research Letters (Phys.org) —Two different research groups working independently have come to the same conclusion, the current pause we’ve experienced in global warming (since 1997) is very likely the last we’re likely to see if current greenhouse gas emission trends continue. One team, with members from several research centers in Japan, has published their findings in the journal Nature Climate Change. The other, based at the University of New South Wales, in Australia, has published their findings in Geophysical Research Letters. More information: 1. Contribution of natural decadal variability to global warming acceleration and hiatus, Nature Climate Change (2014) DOI: 10.1038/nclimate2355AbstractReasons for the apparent pause in the rise of global-mean surface air temperature (SAT) after the turn of the century has been a mystery, undermining confidence in climate projections. Recent climate model simulations indicate this warming hiatus originated from eastern equatorial Pacific cooling4 associated with strengthening of trade winds5. Using a climate model that overrides tropical wind stress anomalies with observations for 1958–2012, we show that decadal-mean anomalies of global SAT referenced to the period 1961–1990 are changed by 0.11, 0.13 and −0.11 °C in the 1980s, 1990s and 2000s, respectively, without variation in human-induced radiative forcing. They account for about 47%, 38% and 27% of the respective temperature change. The dominant wind stress variability consistent with this warming/cooling represents the deceleration/acceleration of the Pacific trade winds, which can be robustly reproduced by atmospheric model simulations forced by observed sea surface temperature excluding anthropogenic warming components. Results indicate that inherent decadal climate variability contributes considerably to the observed global-mean SAT time series, but that its influence on decadal-mean SAT has gradually decreased relative to the rising anthropogenic warming signal.2. Maher, N., A. Sen Gupta, and M. H. England (2014), Drivers of decadal hiatus periods in the 20th and 21st centuries, Geophys. Res. Lett., 41, DOI: 10.1002/2014GL060527.AbstractThe latest generation of climate model simulations are used to investigate the occurrence of hiatus periods in global surface air temperature in the past and under two future warming scenarios. Hiatus periods are identified in three categories: (i) those due to volcanic eruptions, (ii) those associated with negative phases of the Interdecadal Pacific Oscillation (IPO), and (iii) those affected by anthropogenically released aerosols in the mid-twentieth century. The likelihood of future hiatus periods is found to be sensitive to the rate of change of anthropogenic forcing. Under high rates of greenhouse gas emissions there is little chance of a hiatus decade occurring beyond 2030, even in the event of a large volcanic eruption. We further demonstrate that most nonvolcanic hiatuses across Coupled Model Intercomparison Project 5 (CMIP5) models are associated with enhanced cooling in the equatorial Pacific linked to the transition to a negative IPO phase.
The outline of M33s neutral hydrogen disk is shown in black, with all of the discrete detected clouds overlaid. The figure was made by integrating the flux over the velocity range of each cloud, then filling in the lowest contour. The central velocity of each cloud was used so the colours are indicative of this velocity. Velocities shown are relative to M33. Credit: Keenan et al., 2016. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. The detection was made by a team of astronomers led by Olivia C. Keenan of the Cardiff University, U.K. The researchers used a set of data provided by the Arecibo Galaxy Environment Survey (AGES) that utilizes the Arecibo Telescope in Puerto Rico. AGES is a neutral atomic hydrogen survey aimed at searching for galaxies in different areas of the local universe. The scientists have analyzed the data from AGES to look at the neutral hydrogen distribution around M33. Investigating this area, they were searching for any hydrogen clouds that could be starless dwarf satellites of the galaxy. Due to the proximity of M33 and the high quality of AGES data, the team could easily detect new clouds around this galaxy.”It wasn’t too difficult to detect clouds around M33. What was more difficult was working out whether the clouds were part of the disk of M33, near M33 but unattached, or whether they were, in fact, related to our Milky Way galaxy. This meant we had to study each cloud in a lot of detail to work out if it was associated with M33,” Keenan told Phys.org.The team managed to detect 11 new clouds. They also found out that many previously detected clouds are actually part of the low neutral hydrogen disk of M33. However, they were not able to identify any stars associated with these clouds.”We now know a lot about where the gas is around M33 and what it looks like. M33 has an extended neutral hydrogen gas disk which is larger than the optical galaxy as it extends further than the stars. This disk is warped and has lots of clumpy dense regions, which may hint towards a past close encounter with the Andromeda galaxy. M33 also has a population of gas clouds which don’t have any stars associated with them. This is interesting, as we don’t know how these clouds of gas got there, or why they don’t have stars,” Keenan said.According to the study, the largest cloud found by the researchers, designated AGESM33-31, is the most intriguing one. It has a diameter of nearly 60,000 light years and a neutral hydrogen mass of about 12 million solar masses. If the cloud is at the distance of M33, it is larger in size than the galaxy.”We have found a large ring-shaped cloud which appears to be about as big as M33 itself,” Keenan noted.The origin of AGESM33-31 is yet to be determined. One of the hypotheses proposed by the team is that this cloud is the further extension of the Magellanic Stream. The researchers also suppose that the cloud could be the remnants of a dark galaxy that has been disrupted. However, these explanations do not account for the hole observed in this ring-shaped feature.”We have investigated the possibility that this hole may have been formed by a supernova, but found it to be around an order of magnitude too large for this to be a satisfactory explanation. AGESM33-31 remains an interesting and intriguing object, we would need additional observations to allow us to make further comment on its nature,” the scientists wrote in a paper.Keenan concluded that although the Arecibo Telescope is excellent to look for gas around nearby galaxies, a more powerful observatory, like the Square Kilometer Array (SKA), would be needed to continue the search in more remote locations.”We hope that as telescopes improve we will be able to detect more gas around galaxies, and see gas around galaxies which are further away. When the Square Kilometer Array telescope is complete it will be great for this kind of work,” she said.SKA is an international project to built a network of radio telescopes in Australia and South Africa. These telescopes will be tens of times more sensitive and hundreds of times faster at mapping the sky than today’s best radio astronomy facilities. First observations are currently scheduled for 2020. Explore further Citation: Giant hydrogen cloud spotted around the Triangulum Galaxy (2016, May 12) retrieved 18 August 2019 from https://phys.org/news/2016-05-giant-hydrogen-cloud-triangulum-galaxy.html More information: The Structure of Halo Gas Around M33, arXiv:1605.01628 [astro-ph.GA] arxiv.org/abs/1605.01628AbstractUnderstanding the distribution of gas in and around galaxies is vital for our interpretation of galaxy formation and evolution. As part of the Arecibo Galaxy Environment Survey (AGES) we have observed the neutral hydrogen (HI) gas in and around the nearby Local Group galaxy M33 to a greater depth than previous observations. As part of this project we investigated the absence of optically detected dwarf galaxies in its neighbourhood, which is contrary to predictions of galaxy formation models. We observed 22 discrete clouds, 11 of which were previously undetected and none of which have optically detected counterparts. We find one particularly interesting hydrogen cloud, which has many similar characteristics to hydrogen distributed in the disk of a galaxy. This cloud, if it is at the distance of M33, has a HI mass of around 10^7 Msun and a diameter of 18 kpc, making it larger in size than M33 itself. Image: Our flocculent neighbour, the spiral galaxy M33 © 2016 Phys.org (Phys.org)—While peering into the nearby Triangulum Galaxy known as M33, astronomers have detected what appears to be a giant cloud of hydrogen around it. According to research published online on May 5 on the arXiv pre-print server, the cloud is extremely large, even bigger than the galaxy itself. The discovery could improve our knowledge about the distribution of gas in and around galaxies.
Credit: Douglas Petrovich (Phys.org)—Douglas Petrovich, an archaeologist with Ontario’s Wilfrid-Laurier University in Canada has sparked controversy in the ancient history scholarly community by making claims that he has found proof that Hebrew is the world’s oldest alphabet. He has been speaking to media outlets in conjunction with the self-publication of a book he has written regarding his findings called simply World’s Oldest Alphabet. © 2016 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. In interviews, Petrovich claimed that he has found evidence of Israelites in Egypt who converted 22 hieroglyphics into a Hebrew alphabet more than 3,800 years ago. Not everyone in the scholarly community is convinced, however.Most scholars of ancient times agree that the world’s oldest alphabet was probably Semitic, but they have not been able to come to a consensus regarding which it might be. Petrovich contends that converting hieroglyphics into an alphabet was an attempt by those who spoke Hebrew to find a way to create their own written expressions during the time it is believed Israelites lived in Egypt; he claims it predates any other known written alphabet. He notes that he has been working on his research since 2012. He started by translating Middle Egyptian inscriptions on stone tablets along with inscriptions on other tablets (including Sinai 115) that appeared to be precursors or actual examples of a Hebrew alphabet. To conduct his translations, Petrovich has combined letters previously identified from some other scholars with some of his own interpretations—a method that may make it difficult for others in the field to accept his findings. Another point of controversy is the source he offers for dating some of his references—the Bible. He further claims that after assembling the early Hebrew alphabet, he was able to use it to translate 16 Hebrew inscriptions that up till now have been indecipherable. He claims he found references to Moses that aligned with biblical references, and Ahisamach and Asenath, two other biblical figures. He also claims to have found the word “Hebrew.”Petrovich acknowledges that there will be skeptics and even suggests that they attempt to prove or disprove his findings in their own way, insisting that if what he has found is correct then eventually others will come to the same conclusion. Alphabet stone found near Jerusalem Citation: Archeologist claims to have found proof that Hebrew was the first written alphabet (2016, December 8) retrieved 18 August 2019 from https://phys.org/news/2016-12-archeologist-proof-hebrew-written-alphabet.html Explore further
Kolkata: The Central level administrative review meeting of the state government is going to be held on May 8.The meeting will be held at Nabanna Sabhaghar. Sources said that the meeting will start from 1.30 pm. Chief Minister Mamata Banerjee will be taking stock of the progress of different projects in the state.This is the second Central level administrative review meeting that is going to be held in Nabanna Sabhaghar. The first meeting was held here on September 4 in 2017 and on the same day, the state-of-the-art auditorium adjacent to Nabanna was inaugurated. Also Read – Heavy rain hits traffic, flightsIt may be mentioned that before the venue of the meeting was shifted to Nabanna Sabhaghar, the Central level administrative review meeting used to be held at Town Hall. It may be mentioned that the new venue, with a seating capacity of around 1,000 people, is more spacious compared to Town Hall.It may be mentioned that the Chief Minister visits every district to take stock of the progress of different projects and holds district level administrative review meetings. She also holds the Central level administrative review meeting in Kolkata. Also Read – Speeding Jaguar crashes into Merc, 2 B’deshi bystanders killedMinisters and top brass of all departments, senior administrative and police officers and senior officers from districts will be present in the Central level administrative review meeting. The Chief Minister will take stock of the progress of work undertaken by each department. She will also discuss different issues of the departments and the projects taken up by them.It may be recalled that after the last Central level administrative review meeting in September 2017, the Chief Minister had raised her concern over the thirty thousand pending court cases, which was leading to a huge amount of recurring cost to the state government. She had also directed the concerned departments to take necessary steps in this regard.Meanwhile, the meeting of the state plan for the 2019-20 financial year was held in the state secretariat on Thursday. The meeting was led by Chief Secretary Malay De. Senior officials of all the departments attended the meeting, in which there was preliminary discussion on planning of each of the departments for the next financial year.
Upping their ante against the land bill, MPs of several opposition parties are planning to take out a march to Rashtrapati Bhavan next Tuesday to register their protest against the amendments proposed to be carried out in the Act of 2013. JD(U) chief Sharad Yadav is coordinating with other parties like Congress, TMC, SP, BSP, DMK and Left parties to organise the protest march, sources said here on Friday. “It is proposed to be a march of non-NDA MPs to the Rashtrapati Bhavan… Sharad Yadav is coordinating,” a source said. Congress has expressed its willingness to participate in the march, the sources said. The land bill was passed by the Lok Sabha three days back after the government carried out nine amendments and persuaded most of its allies to support it.