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  • richardmitnick 9:08 am on April 21, 2020 Permalink | Reply
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    From Nature (via SymmetryMag): “This black-hole collision just made gravitational waves even more interesting” 

    From Nature

    20 April 2020
    Davide Castelvecchi

    An unprecedented signal from unevenly sized objects gives astronomers rare insight into how black holes spin.

    1
    A visualization of a collision between two differently sized black holes.Credit: N. Fischer, H. Pfeiffer, A. Buonanno (Max Planck Institute for Gravitational Physics), Simulating eXtreme Spacetimes (SXS) Collaboration

    Gravitational-wave astronomers have for the first time detected a collision between two black holes of substantially different masses — opening up a new vista on astrophysics and on the physics of gravity. The event offers the first unmistakable evidence from these faint space-time ripples that at least one black hole was spinning before merging, giving astronomers rare insight into a key property of these these dark objects.

    “It’s an exceptional event,” said Maya Fishbach, an astrophysicist at the University of Chicago in Illinois. Similar mergers on which data have been published all took place between black holes with roughly equal masses, so this new one dramatically upsets that pattern, she says. The collision was detected last year, and was unveiled on 18 April by Fishbach and her collaborators at a virtual meeting of the American Physical Society, held entirely online because of the coronavirus pandemic.

    The Laser Interferometer Gravitational-Wave Observatory (LIGO) — a pair of twin detectors based in Hanford, Washington, and Livingston, Louisiana — and the Virgo observatory near Pisa, Italy, both detected the event, identified as GW190412, with high confidence on 12 April 2019.

    MIT /Caltech Advanced aLigo


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    The LIGO–Virgo collaboration, which includes Fishbach, posted its findings on the arXiv preprint server [https://arxiv.org/abs/2004.08342].

    LIGO made the first discovery of gravitational waves in September 2015, detecting the space-time ripples from two merging black holes. LIGO, later joined by Virgo, subsequently made ten more detections in two observing runs that ended in 2017: nine more black-hole mergers and one collision of two neutron stars, which helped to explain the origin of the Universe’s heavy chemical elements.

    The third and most recent run started on 1 April 2019 and ended on 27 March 2020, with a month-long break in October. Greatly improved sensitivity enabled the network to accumulate around 50 more ‘candidate events’ at a rate of roughly one per week. Until now, the international collaboration had unveiled only one other event from this observation period — a second merger between two neutron stars, dubbed GW190425, that was revealed in January.

    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 1:40 pm on February 18, 2020 Permalink | Reply
    Tags: "30 years of the iron hypothesis of ice ages", , , Nature Magazine   

    From Nature: “30 years of the iron hypothesis of ice ages” 


    From Nature

    17 February 2020

    In 1990, an oceanographer who had never worked on climate science proposed that ice-age cooling has been amplified by increased concentrations of iron in the sea — and instigated an explosion of research.

    Thirty years ago this month, John Martin proposed a solution to one of the biggest mysteries of Earth’s climate system: how was nearly one-third of the carbon dioxide in the atmosphere (about 200 gigatonnes of carbon) drawn into the ocean as the planet entered the most recent ice age, then stored for tens of thousands of years, and released again as the ice sheets melted? These large natural cycles in atmospheric CO2 levels (Fig. 1a) were revealed in 1987 by an analysis of ancient air bubbles trapped in the first long ice cores taken from the Antarctic ice sheet [1]. Martin recognized that iron was a key ingredient that could have transformed the surface ocean during glacial times. His landmark iron hypothesis [2], published in Paleoceanography, described a feedback mechanism linking climatic changes to iron supply, ocean fertility and carbon storage in the deep ocean.

    2
    Figure 1 | The anti-correlated data that inspired the iron hypothesis. a, Measurements of air bubbles trapped in cores drilled from the Antarctic ice sheet show that atmospheric levels of carbon dioxide were significantly lower during the coldest periods (shaded regions) than during modern times (data from ref. [16]; CO2 concentrations are shown in parts per million by volume; p.p.m.v.). b, The ice-core records also reveal that more iron was transported to the Southern Ocean in wind-blown dust during the coldest periods than during warmer times (data from ref. [17]; iron flux is measured in micrograms per square metre per year). In 1990, Martin2 hypothesized that the increased levels of iron in the Southern Ocean during the coldest periods fertilized the growth of photosynthetic microorganisms in the surface Southern Ocean, which therefore produced more biomass from CO2. This, in turn, would have increased the strength of the biological pump, a mechanism that sequesters some of the biomass (and the carbon within it) in the deep ocean. Martin proposed that the stronger biological pump explains why so much atmospheric CO2 is drawn into the ocean during cold times.

    Two hundred gigatonnes is a lot of carbon to periodically withdraw from and release to the atmosphere. In the 1980s, a handful of models (see ref. [3], for example) had shown that an increase in biomass production in polar ocean regions was the most effective process for removing so much atmospheric carbon. Photosynthetic organisms in the surface ocean convert CO2 from the atmosphere into biomass, much of which is subsequently broken down into CO2 again by other organisms and returned to the atmosphere. But part of the biomass sinks into the deep ocean, which therefore effectively serves as a large storage reservoir of dissolved CO2. This mechanism of CO2 removal is called the biological pump.

    However, biomass production requires not only CO2, but also other nutrients to build lipids, proteins and enzymes. Researchers were struggling to ascertain how the ocean’s abundance of key nutrients, such as nitrates or phosphates, might have increased during glacial times to fuel a stronger biological pump.

    Martin argued that iron is another nutrient that limits the biological pump. He suggested that the modern marine ecosystem of the Southern Ocean around Antarctica is starved of iron, and therefore relatively low in biomass, despite having abundant nitrates and phosphates. But during glacial times, strong winds over cold, sparsely vegetated continents could have transported large amounts of iron-bearing dust into this ocean (Fig. 1b). Martin reasoned that this dust could have fertilized marine ecosystems and strengthened the biological pump, so that more carbon was transferred into the deep ocean, lowering atmospheric CO2 levels.

    Around the time of publication, evidence for high dust delivery during glacial periods had just emerged from studies of deep Antarctic ice cores [4]. But there were no reliable measurements of dissolved iron in the Southern Ocean that could confirm that its surface waters are iron-starved in modern times, or data supporting the proposal that delivery of iron-rich dust would make a difference to ocean productivity. It was clear, however, that large patches of the world’s ocean had much lower quantities of biomass than would be expected on the basis of the concentrations of key nutrients such as nitrates and phosphates. But many researchers argued that this was due to natural overgrazing of algae by herbivores [5].

    The idea that modern algal growth is limited by iron availability had, in fact, been proposed [6] in the 1930s, but had been incorrectly discounted by oceanographers — who had measured plenty of iron in seawater samples collected from the waters around their iron ships [7]. Martin was one of the first oceanographers to implement painstaking procedures to avoid the contamination of samples and to determine that iron concentrations in the north Pacific Ocean were extremely low [7], certainly low enough to curtail biomass production.

    Despite the initial scepticism that greeted the iron hypothesis, 12 separate experiments [8] were carried out between 1993 and 2005 in which around 300–3,000 kilograms of dissolved iron were injected into small patches of the Southern Ocean, the equatorial Pacific Ocean and the north Pacific. The biomass of algae increased wherever iron was added, as biological production surged.

    Unfortunately, Martin died mere months before the first of these experiments, and did not witness the ocean-scale confirmation of his hypothesis, nor the internationally coordinated campaign to measure iron geochemistry throughout the world’s oceans [9] — which confirmed iron limitation and revealed the intricate strategies used by marine ecosystems to acquire and recycle iron [10].

    Earth scientists also tried to test the iron hypothesis computationally using simple ocean models. They used the changes in the dust-accumulation rate recorded in ice cores as input to simulate changes in iron delivery to the Southern Ocean, and data from the experimental iron fertilizations to calculate how this iron could affect algal growth and the biological pump. Such models could reproduce the timing and magnitude of about half of the observed decrease in atmospheric CO2 levels during glacial periods [11]. Iron fertilization is therefore clearly an important process that causes atmospheric changes, but might not be the only one.

    Finding data to prove that biological production had been higher during glacials was a harder task — after all, the ecosystem during the most recent glacial period (about 20,000 years ago) is long dead. One possible solution was to extract cores from sediments piled on the sea floor, to see whether the mineral skeletons of algae accumulated faster during glacial times than in the modern era. However, the results were often ambiguous12, for several reasons: many algae don’t produce a preservable skeleton; numerous factors determine what proportion of biological remains is preserved on the sea floor; and the location of biological production changes through time as ocean fronts and sea-ice positions migrate.

    Fortunately, Martin [2] and others [13] had anticipated an alternative, global-scale test of the biological pump during glacial times. If more biomass reached the deep ocean during glacials, then deep-sea microorganisms would use up more oxygen as they consumed it, decreasing the concentration of oxygen in deep waters. Evidence of deep-ocean oxygen depletion would therefore be indicative of a strong biological pump.

    Martin recognized that the presence of certain microfossils in glacial-age sediments meant that the deep ocean had not become completely devoid of oxygen during glacials. But although this evidence crudely constrained estimates of the degree to which iron fertilization might have enhanced productivity during glacials, it could not be used to determine whether levels of deep-ocean oxygen were lower than during modern times. Since then, analysis of more-sensitive geochemical records indicates that the oxygen concentration in bottom waters did decrease during glacial times [14]. This provides the strongest confirmation yet of the large-scale accumulation of carbon in the deep ocean during glacial periods owing to a stronger biological pump.

    Slower rates of mixing between the deep and shallow oceans could also have enhanced the biological pump during glacials. The latest generation of climate models in which the ocean and atmosphere are coupled can test the contribution of the multiple processes that could have resulted in a reduction in bottom-water oxygen levels. Such models indicate that mixing rates can account for only half of the observed deep-ocean storage of CO2 during the glacial period, and that iron fertilization of the Southern Ocean is the major cause of the extra CO2 storage observed [15].

    Martin concluded his paper by saying that iron availability “appears to have been a player” in strengthening the biological pump during glacial cycles, but that the size of its role remained to be determined. Thirty years later, the evidence convincingly shows that iron fertilization of the Southern Ocean was indeed a leading actor in this global-climate feedback.

    References [See the original article for the links to these references.]

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    See the full article here .

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 4:01 pm on September 4, 2019 Permalink | Reply
    Tags: "Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime", Carroll argues that the many-worlds theory is the most straightforward approach to understanding quantum mechanics. It accepts the reality of the wave function., In quantum mechanics the world unfolds through a combination of two basic ingredients. One is a smooth fully deterministic wave function., Instead new worlds are created in which each possibility is a reality., Largely because of its purely logical character Carroll calls Everett’s brainchild “the best view of reality we have”., Like many physicists Carroll assumes that reality is whatever a scientific theory says it is., Many physicists accept this picture at face value in a conceptual kludge known as the Copenhagen interpretation authored by Niels Bohr and Werner Heisenberg in the 1920s., Nature Magazine, , Quantum mechanics is the basic framework of modern subatomic physics., , Six decades on the theory is one of the most bizarre yet fully logical ideas in human history growing directly out of the fundamental principles of quantum mechanics ., The many-worlds theory differs from the concept of the multiverse which pictures many self-contained universes in different regions of space-time., The many-worlds theory posits that parallel worlds constantly branch off from each other moment by moment., The many-worlds theory states that when an event happens in our world the other possibilities contained in the wave function do not go away., the predictions are probabilistic and what makes the function collapse is mysterious., The wave function is unobservable, What the wave function ‘is’ is the key source of contention in interpreting quantum mechanics.   

    From Nature: “The bizarre logic of the many-worlds theory” 

    Nature Mag
    From Nature

    02 September 2019
    Robert P. Crease

    1
    Originating in the 1950s, the many-worlds theory posits that parallel worlds constantly branch off from each other, moment by moment.Credit: Shutterstock

    Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime
    Sean M Carroll Oneworld (2019)

    At the beginning of Something Deeply Hidden, Sean M Carroll cites the tale of the fox and the grapes from Aesop’s Fables. A hungry fox tries to reach a bunch of grapes dangling from a vine. Finding them beyond his grasp, but refusing to admit failure, the fox declares the grapes to be inedible and turns away. That, Carroll declares, encapsulates how physicists treat the wacky implications of quantum mechanics.

    Carroll wants that to stop. The fox can reach the grapes, he argues, with the many-worlds theory. Originated by US physicist Hugh Everett in the late 1950s, this envisions our Universe as just one of numerous parallel worlds that branch off from each other, nanosecond by nanosecond, without intersecting or communicating. (The many-worlds theory differs from the concept of the multiverse, which pictures many self-contained universes in different regions of space-time.)

    Six decades on, the theory is one of the most bizarre yet fully logical ideas in human history, growing directly out of the fundamental principles of quantum mechanics without introducing extraneous elements. It has become a staple of popular culture, although the plots of the many films and television series inspired by it invariably flout the theory by relying on contact between the parallel worlds, as in the 2011 movie Another Earth.

    In Something Deeply Hidden, Carroll cogently explains the many-worlds theory and its post-Everett evolution, and why our world nevertheless looks the way it does. Largely because of its purely logical character, Carroll calls Everett’s brainchild “the best view of reality we have”.

    Catch a wave

    Quantum mechanics is the basic framework of modern subatomic physics. It has successfully withstood almost a century of tests, including French physicist Alain Aspect’s experiments confirming entanglement, or action at a distance between certain types of quantum phenomena. In quantum mechanics, the world unfolds through a combination of two basic ingredients. One is a smooth, fully deterministic wave function: a mathematical expression that conveys information about a particle in the form of numerous possibilities for its location and characteristics. The second is something that realizes one of those possibilities and eliminates all the others. Opinions differ about how that happens, but it might be caused by observation of the wave function or by the wave function encountering some part of the classical world.

    Many physicists accept this picture at face value in a conceptual kludge known as the Copenhagen interpretation, authored by Niels Bohr and Werner Heisenberg in the 1920s. But the Copenhagen approach is difficult to swallow for several reasons. Among them is the fact that the wave function is unobservable, the predictions are probabilistic and what makes the function collapse is mysterious.

    2
    Hugh Everett (second from right) originated the many-worlds theory. (Also pictured, left to right: Charles Misner, Hale Trotter, Niels Bohr and David Harrison.)Credit: Alan Richards/AIP Emilio Segre Visual Archives.

    What are we to make of that collapsing wave? The equations work, but what the wave function ‘is’ is the key source of contention in interpreting quantum mechanics. Carroll outlines several alternatives to the Copenhagen interpretation, along with their advantages and disadvantages.

    One option, the ‘hidden variables’ approach championed by Albert Einstein and David Bohm, among others, basically states that the wave function is just a temporary fix and that physicists will eventually replace it. Another tack, named quantum Bayesianism, or QBism, by Christopher Fuchs, regards the wave function as essentially subjective. Thus it is merely a guide to what we should believe about the outcome of measurements, rather than a name for a real feature of the subatomic world. Late in his life, Heisenberg proposed that we have to change our notion of reality itself. Reaching back to a concept developed by Aristotle — ‘potency’, as in an acorn’s potential to become an oak tree, given the right context — he suggested that the wave function represents an “intermediate” level of reality.

    Carroll argues that the many-worlds theory is the most straightforward approach to understanding quantum mechanics. It accepts the reality of the wave function. In fact, it says that there is one wave function, and only one, for the entire Universe. Further, it states that when an event happens in our world, the other possibilities contained in the wave function do not go away. Instead, new worlds are created, in which each possibility is a reality. The theory’s sheer simplicity and logic within the conceptual framework of quantum mechanics inspire Carroll to call it the “courageous” approach. Don’t worry about those extra worlds, he asserts — we can’t see them, and if the many-worlds theory is true, we won’t notice the difference. The many other worlds are parallel to our own, but so hidden from it that they “might as well be populated by ghosts”.

    Branching cats

    For physicists, the theory is attractive because it explains many puzzles of quantum mechanics. With Erwin Schrödinger’s thought experiment concerning a dead-and-alive cat, for instance, the cats simply branch into different worlds, leaving just one cat-in-a-box per world. Carroll also shows that the theory offers simpler explanations of certain complex phenomena, such as why black holes emit radiation. Furthermore, the theory might help to develop still-speculative ideas about conundrums such as how to combine quantum mechanics with relativity theory.

    Something Deeply Hidden is aimed at non-scientists, with a sidelong glance at physicists still quarrelling over the meaning of quantum mechanics. Carroll brings the reader up to speed on the development of quantum physics from Max Planck to the present, and explains why it is so difficult to interpret, before expounding the many-worlds theory. Dead centre in the book is a “Socratic dialogue” about the theory’s implications. This interlude, between a philosophically sensitive physicist and a scientifically alert philosopher, is designed to sweep away intuitive reservations that non-scientists might have.

    Nevertheless, non-scientists might have lingering problems with Carroll’s breezy, largely unexamined ideas about “reality”. Like many physicists, he assumes that reality is whatever a scientific theory says it is. But what gives physicists a lock on this concept, and the right to say that the rest of us (not to mention, say, those in extreme situations such as refugees, soldiers and people who are terminally ill) are living through a less fundamental reality? Could it be that we have to follow Heisenberg’s lead? That is, must we rely on tools for talking about the complexities of reality that philosophers have developed over millennia to explain why the fox has such a tough time reaching those grapes?

    What a wacky idea.

    See the full article here .

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    Please help promote STEM in your local schools.

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 12:03 pm on August 29, 2019 Permalink | Reply
    Tags: "Make science PhDs more than just a training path for academia", , , Nature Magazine   

    From Nature: “Make science PhDs more than just a training path for academia” 

    Nature Mag
    From Nature

    28 August 2019
    Sarah Anderson

    Science PhD programmes cater almost exclusively to students bound for academia, but they don’t have to.

    1
    Credit: IconicBestiary/Getty

    My committee member looked up from the document in his hand, which detailed my ideas for my research proposal. He cleared his throat: “You know, when you apply for faculty positions…” he began. I gave a quick, impulsive nod in response, but thought to myself, “That’s never going to happen.”

    I’m a PhD candidate in chemistry with no intention of pursuing a career in academia, and I’m certainly not alone: out of 81 students in my programme, only 40% plan to go into academia. A more comprehensive survey of 5,700 science doctoral students worldwide, conducted in 2017, found that 75% of respondents wanted to work in academia after graduation, although a significant portion of those reported equivalent interest in the industry sector, suggesting indecision [1]. Clearly, the desire to pursue academia is not universal among PhD students. Furthermore, tenure-track job openings are a rare find: a study of job availability carried out in 2014 concluded that only 13% of PhD graduates can attain academic positions in the United States [2].

    Despite the lack of exclusive interest in academic careers and the low demand for professors, PhD programmes are designed to accommodate students with their sights set on academia. This fact is evident in the requirements that PhD students must meet to earn their doctoral degree, as well as the events hosted and sponsored by science departments.

    Research is of course at the heart of a PhD, and assessment of productivity through a qualifying exam and thesis defence is needed to bestow a doctorate. But the goal of an original research proposal, such as the one my committee member was holding, isn’t to evaluate progress, but rather to serve as practice for developing exploratory project ideas and securing funding for them — skills most relevant to future professors.

    This agenda isn’t hidden: the reminder that a great proposal could be used later in faculty applications was dangled in front of my colleagues and I as a largely inapplicable and therefore ineffective incentive to put in the work.

    Also, the majority of events hosted by science departments — seminars given by professors, lunches with professors, panels of professors — are of greatest value to students taking an academic route.

    There are typically more opportunities for non-academic professional development outside of a candidate’s department of study, such as science-journalism and business-certification courses. But a lack of department promotion and sponsorship of these programmes means that students are often either unaware of their existence or feel discouraged from participating.

    Research proposals are one example in which PhD programme requirements could be better tailored to the career goals of each individual student. Those interested in science communication shouldn’t waste their time producing a proposal for research they’re not interested in performing. They could instead write a piece on their research targeted at a non-expert audience, for example. Similarly, those planning to enter industry could pitch a new product, and those aiming to become lecturers could participate in and report on a teaching internship. Choosing a career track with corresponding requirements could become as standard as selecting an inorganic, organic, physical or biological chemistry track.

    The events hosted and sponsored by science departments are an area in which graduate school could become more inclusive and beneficial to students pursuing careers beyond academia. There are many professionals in industry and non-conventional fields who could occupy some slots on the department calendar. Furthermore, by promoting external programmes aimed at non-academic-career preparation, science departments could ensure that students are aware of such opportunities and display public support for their participation.

    To successfully implement these changes, we must first subvert the assumption on which PhD programmes seem to be built: that their participants plan to pursue academia. This mindset is in part a consequence of PhD programmes being crafted by professors who used their own career trajectory as a template.

    But I suspect it’s also a product of the unfortunate reality that PhD advisers simply do not view non-academic careers with the same degree of admiration. The fact that multiple people have written articles on how to break the apparently devastating news to your adviser that you aren’t following in their footsteps speaks volumes. If academia can’t appreciate the inherent value of professions beyond ‘research professor’, then maybe it can at least recognize the benefits it gains from having PhD-trained scientists in roles outside academia.

    For example, science communicators create crucial dialogue between scientists and the public, helping to establish a wider audience for researchers’ work and prevent misinterpretation of findings. Those in the field of science policy help to inform important regulations that affect national agencies funding academic research. High-school science teachers, lecturers and lab instructors are training the next generation of graduate students who will work in university labs. Hopefully, the PhD programmes that these students experience help them to feel validated in and prepared for whatever career path they choose.

    References

    1. Woolston, C. Nature 550, 549–552 (2017).
    2. Larson, R. C., Ghaffarzadegan, N. & Xue, Y. Syst. Res. Behav. Sci. 31, 745–750 (2014).

    See the full article here .

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    Please help promote STEM in your local schools.

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 12:41 pm on May 9, 2019 Permalink | Reply
    Tags: , , , , , Large High Altitude Air Shower Observatory (LHAASO) China, Nature Magazine   

    From Nature: “China’s mountain observatory begins hunt for origins of cosmic rays” 

    Nature Mag
    From Nature

    08 May 2019
    David Cyranoski

    1
    Large High Altitude Air Shower Observatory (LHAASO)

    The Large High Altitude Air Shower Observatory is now operational.

    China’s search for the origins of high-energy cosmic rays — particles that shower Earth from outside the Solar System — has kicked off. A ceremony to launch the first phase of the Large High Altitude Air Shower Observatory (LHAASO) was held on 26 April, three weeks after the facility started making observations.

    Cosmic rays are composed of subatomic particles, such as protons or atomic nuclei, which can reach almost the speed of light when travelling through space. A number of phenomena, such as supernovae, are thought to produce them, but the origin of the most energetic of these particles, known as ultra-high-energy cosmic rays, is still a mystery.

    That’s in part because cosmic rays, which carry a charge and so are bounced around by magnetic fields on their way to Earth, are difficult to trace.

    A different track

    The LHAASO will take an indirect approach. Set more than 4.4 kilometres above sea level in Daocheng, Sichuan, on the eastern part of the Tibetan Plateau, it will track another form of radiation — high-energy γ-rays. Researchers suspect that these come from the same astrophysical phenomena as cosmic rays, but because γ-rays don’t carry a charge they travel in straighter lines and are easier to trace. Following the path of γ-rays could therefore lead scientists to a cosmic-ray producer.

    Sources of high-energy γ-rays have been identified, including flaring supermassive black holes called blazars. None of these has also been confirmed to produce cosmic rays, although there are hints that they do.

    Altitude advantage

    The LHAASO’s four detector arrays will be the first to measure ultra-high-energy γ-rays — those in the peta-electronvolt (1015 eV) range. Earth’s upper atmosphere absorbs these rays, which splinter into showers of lower-energy particles. The observatory’s high altitude means its detectors will be able to capture these particles before they decay to much lower energies.

    A better understanding of cosmic rays could reveal what distant galaxies are composed of, and provide clues to the processes that accelerate nuclei to such great speeds.

    The LHAASO is managed by the Institute of High Energy Physics in Beijing, and is scheduled to be fully operational by 2021.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

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    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 8:02 pm on March 21, 2019 Permalink | Reply
    Tags: "Gigantic EU research programme takes shape" (U.S.- they are eating your lunch), Horizon Europe will fund a mix of academia–industry collaborations and discovery science, Innovation innovation innovation, Nature Magazine   

    From Nature: “Gigantic EU research programme takes shape” (U.S.- they are eating your lunch) 

    Nature Mag
    From Nature

    20 March 2019

    Horizon Europe will fund a mix of academia–industry collaborations and discovery science — but its proposed budget of €100 billion has yet to be agreed.

    1
    The European Parliament Building, Brussels, Belgium, 22 December 2017, Steven Lek

    The European Union’s three governing institutions — the European parliament, council and commission — reached agreement in the small hours of 20 March on the outline of the EU’s next seven-year research-funding programme, Horizon Europe.

    Like its predecessor, Horizon 2020, the new programme will fund collaborations between academia and industry, and prestigious discovery science. But the agreement also includes some fresh ideas, including a greater focus on innovation and initiatives to help poorer nations compete for funds.

    One big element that is yet to be decided is the budget for Horizon Europe — due to launch in 2021 — which has been proposed at around €100 billion (US$114 billion) and is expected to be the largest EU research programme yet.

    “Europe wants to go big on research,” says Christian Ehler, a Member of the European Parliament from Germany and one of the rapporteurs for Horizon Europe.

    The agreement marks the end of a series of tough negotiations between the three EU bodies. Talks began in January to resolve sticking points in the commission’s original proposal, which was published last June. The framework’s structure must please both the parliament and the EU’s individual member states.

    The agreement’s details show that at least half of Horizon Europe’s money will be spent on collaborative programmes, in which academic scientists, research institutes and industry work together.

    These will include heavily financed ‘mission’ projects that target specific societal problems, akin to the billion-euro flagship schemes in the current EU research programme, Horizon 2020, that focus on the brain, graphene and quantum technologies. The topics of Horizon Europe’s missions are yet to be decided.

    Most of the rest of the money will go to familiar, prestigious programmes for discovery science, such as the European Research Council and the Marie Skłodowska-Curie Actions scheme — which trains young scientists and promotes international mobility — as well as to programmes to support innovation.

    Innovation, innovation, innovation

    Horizon Europe has a greater focus than its predecessor on innovation: a pumped-up European Innovation Council will invest in small and medium-sized technology companies, and provide competitive grants and other forms of support. The council will work alongside the established European Institute of Innovation and Technology, which supports large communities of scientists in industry and academia to develop innovative products or services.

    New elements in Horizon Europe include programmes aimed at supporting collaboration between museums in EU nations; a fast-track application procedure to develop innovative ideas proposed by the scientific community; and special initiatives to help former-communist countries to compete for research funds.

    The agreement must still be formally approved by the full European Parliament and the council. As well as the budget, it leaves open a key but sensitive decision — the rules under which non-EU member states will be able to participate.

    The three EU institutions want much of Horizon Europe, and particularly the parts relating to global societal challenges, to be open to scientists around the globe. But how this will be organized depends on final budget agreements. The European Commission originally proposed a budget of €94.1 billion, a 22% increase on Horizon 2020’s funds, but the parliament has called for €120 billion.

    The EU institutions will consider these aspects again after the European Parliament elections in May, but are unlikely to reach a decision before the end of the year.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 9:34 am on October 23, 2018 Permalink | Reply
    Tags: , , , KAUST, Nature Magazine   

    KAUST via Nature Magazine: “The holistic approach to catalyzing change” 

    1

    KAUST

    via

    Nature Mag
    Nature Magazine

    Rethinking industry-scale catalytic processes could slash global energy consumption and even turn carbon dioxide into a valuable commodity.

    Sep 6, 2018

    2

    Jorge Gascon
    Professor/Center Director

    Chemical catalysts don’t spring to mind as revolutionary materials, yet Jorge Gascon, director of the KAUST Catalysis Center, says catalysts have sparked some of the biggest revolutions in human history. Take the Haber Bosch process, for example. This first practical method for industrial synthetic fertilizer production, developed in the early 1900s, triggered the agricultural revolution that fuels farming today.

    Catalysis research is poised to change the world again, Gascon claims. “We are about to have another revolution in the way we use our resources and in the way we produce and store energy, and I believe catalysis will play a huge role,” he says. “We at KAUST are in an excellent position to contribute strongly to that transition.”

    Gascon’s research—and that of the Center he has led since joining KAUST in October 2017—revolves around sustainability. “The main purpose of my group is to develop and deploy sustainable technologies for the production of chemicals, energy carriers and new environmental applications. Process intensification, feedstock efficiency and reduction of energy usage are our main objectives.”

    For example, the team recently gained insights that could significantly enhance the performance of catalysts that convert methanol into major chemical feedstocks called olefins1,2. These high-demand chemicals are traditionally sourced from oil, but new catalysts—which Gascon’s work is helping to make more efficient—enable olefin production from coal and natural gas, alleviating a bottleneck in olefin supply.

    Another major area of focus in Gascon’s lab, as well as others labs in the Center, is to develop catalysts that can efficiently turn carbon dioxide into a valuable chemical feedstock. The team has developed several catalysts that can combine CO2 with hydrogen, converting the troublesome greenhouse gas into a range of useful small hydrocarbon molecules.

    At the moment, the hydrogen for the process comes from natural gas in such a way that it generates CO2. “If the situation changes and we start to use solar energy to produce hydrogen from water, then that hydrogen can be used to make very useful products out of carbon dioxide,” Gascon says. Should governments introduce a tax on carbon dioxide emissions, recycling CO2 would become even more favorable. “Our main target is to make those technologies as efficient as possible so it becomes attractive to valorize carbon dioxide.”

    The catalysts Gascon works with are typically porous crystalline solids, such as zeolites and metal-organic frameworks. “I like these materials because working with crystalline structures gives you much more control over design,” Gascon says. The structures of these materials can be tuned at the nanoscale. By making such changes and noting the effects on catalytic performance, it is possible to gain deep insights into how the catalysts function and thus they can be improved. “Being able to explain a thing you can measure at the macroscale, by the structures that you build at the nanoscale, is super nice,” Gascon says.

    The great strength of the Catalysis Center is that there are researchers focused on every aspect of catalytic reaction development and implementation, Gascon adds. “We design new active sites at the nanoscale, but we also design how the catalyst particles should look, and now we are starting to design how reactors should look,” Gascon says. “We are starting to have a holistic approach. I think the Catalysis Center is probably unique in that we are able to cover almost every relevant aspect in catalysis.”

    One of the Center’s flagship projects, which began its second phase in early 2018, is the one-step conversion of crude oil to chemicals. The project illustrates the power of the holistic approach. Today, refineries pass crude oil through cleaning steps, then separate the oil into various chemical fractions, before those fractions are catalytically processed to form chemical feedstocks and fuels. “We want to avoid all those initial steps and go directly to the processing part,” says Gascon. Cutting these steps could save a lot of energy.

    To directly make chemicals from crude oil, you need catalysts that are very robust and resistant to poisoning by contaminants in the oil. But for the process to be successful, the team needs to go far beyond the catalyst itself. “You need to think of different reactor concepts to the ones that are used at the moment,” Gascon says. “You need to redesign the whole process. This is the type of research where I believe our Center can make a difference.”

    The project is a revolutionary idea in the best tradition of catalysis research. And the unique funding structure, facilities and expertise at KAUST make the Catalysis Center the place to do it, says Gascon. “From a research point of view, this is like Disneyland,” he says. “The possibilities here are absolutely amazing. This is probably the only place in the world where you are your own limit.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 11:59 am on September 17, 2018 Permalink | Reply
    Tags: 2015 Paris climate agreement, , Australia has no climate-change policy — again, , , Nature Magazine   

    From Nature: “Australia has no climate-change policy — again” 

    Nature Mag
    From Nature

    Scientists say the country will now struggle to meet it commitments to the Paris agreement.

    17 September 2018
    Adam Morton

    1
    Large parts of Australia are enduring a crippling drought.Credit: David Gray/Reuters

    Australia’s new prime minister has abandoned the country’s policy for cutting greenhouse-gas emissions. Climate scientists say the move means the government has effectively dropped its commitment to the 2015 Paris climate agreement.

    “They’ve walked away from Paris without saying it, hoping no one would notice,” says Lesley Hughes, a climate-change scientist at Macquarie University in Sydney. Without a policy to cut carbon dioxide pollution, the government is dropping its international commitment by default, she says.

    Australia now becomes the second advanced economy after the United States to drop emissions-reduction policies since the 2015 Paris climate conference. President Donald Trump signed an executive order to start removing climate regulations in March 2017 and pulled the US out of the Paris agreement in June 2017.

    Australia’s effective abandonment of Paris can be traced back to late August, when the ruling conservative Liberal Party abruptly replaced former leader Malcolm Turnbull with Prime Minister Scott Morrison. The leadership change came after some party members objected to a policy that would have required electricity companies to meet emissions targets. Morrison subsequently said that he was abandoning the policy, called the National Energy Guarantee (NEG), and would instead focus on reducing the cost of energy for the public.

    The NEG is the fourth national climate policy rejected by Australia’s conservative government since it was elected in 2013, and comes as large parts of country feel the effects of global warming — a crippling drought grips the eastern states and dozens of bushfires have erupted unseasonably early in those regions.

    Some government members have even suggested that the country should join the Trump administration in officially withdrawing from the Paris agreement. Morrison has rejected this idea. He says Australia is on track to meet the target it announced before the Paris conference: to cut emissions by 26–28% below 2005 levels by 2030.

    But there is little evidence to suggest the government will be able to meet this target without new policies. In August, government advisers said it was unlikely that the electricity sector, responsible for one-third of Australia’s emissions, would reduce its emissions by 26% unless a policy was introduced to drive cleaner energy generation over the next decade.

    National emissions have risen each year since 2014, when the government repealed laws requiring big industrial emitters to pay for their emissions. There are also no significant policies to reduce the other major sources of pollution, such as transport, agriculture, heavy industry and mining, which together generate nearly two-thirds of Australia’s carbon emissions.

    Although the NEG was a modest policy, proposed after several more effective schemes failed to win political support, it had the potential to win the backing of the centre-left opposition Labor Party, says John Church, a specialist in sea-level rise at the Climate Change Research Centre (CCRC) at the University of New South Wales in Sydney. That would have enabled the policy to pass through parliament and into law. The policy also had the support of the business community, which has been calling for climate and energy strategies that encourage investment in new and cleaner power plants, he says. “Walking away from it was a disaster.”

    Sarah Perkins-Kirkpatrick, an authority on heatwaves, also at the CCRC, says government motivation to do something about climate change seems to have disappeared altogether. When she briefed senior officials on the latest climate-change science in August, she left the meeting feeling optimistic that more policies were coming. “People were trying to get things done, but now that’s not the case at all,” she says. “I’m extremely frustrated.”

    Public concern

    The decision to drop the policy also goes against the public’s support for action on climate change, says Hughes. A poll of 1,756 people, published on 12 September by research and advocacy organization the Australia Institute, found that 73% of respondents were concerned about climate change and 68% wanted domestic climate targets in line with the country’s Paris commitment.

    But Australia’s lack of climate policy could be short-lived. A national election is due by May 2019, and recent polls suggest that the Labor Party, led by former union boss Bill Shorten, is favoured to win. Labor says it would set a new emissions target of a 45% cut by 2030, although it has not revealed how it would reach the target. In the meantime, some states have mandated ambitious renewable-energy targets, and business leaders say investment in clean energy is increasing because it is now the cheapest option.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 12:43 pm on September 7, 2018 Permalink | Reply
    Tags: Nature Magazine, Peer reviewers unmasked: largest global survey reveals trends   

    From Nature: “Peer reviewers unmasked: largest global survey reveals trends” 

    Nature Mag
    From Nature

    07 September 2018
    Inga Vesper

    Scientists in emerging economies respond fastest to peer review invitations, but are invited least.

    Scientists in developed countries provide nearly three times as many peer reviews per paper submitted as researchers in emerging nations, according to the largest ever survey of the practice.

    The report — which surveyed more than 11,000 researchers worldwide — also finds a growing “reviewer fatigue”, with editors having to invite more reviewers to get each review done. The number rose from 1.9 invitations in 2013 to 2.4 in 2017.

    The Global State of Peer Review report was undertaken by Publons, a website that helps academics to track their reviews and other contributions to scientific journals. The authors used data from the survey, conducted from May to July 2018, as well as data from Publons, Web of Science Core Collection and Scholar One Manuscripts databases.

    The report notes that finding peer reviewers is becoming harder, even as the overall volume of publications rises globally (see ‘Is reviewer fatigue setting in?’).

    2
    Source: Global State of Peer Review 2018

    And although contributions to peer review from emerging economies are lower compared with developed countries, they are rising rapidly, says Andrew Preston, managing director of Publons, in London. “Peer reviews lag publication, so it will take a few years for emerging regions to catch up,” he says.
    Data digging

    Researchers in leading science locations, such as the United States, the United Kingdom and Japan, write nearly 2 peer reviews per submitted article of their own, compared with about 0.6 peer reviews per submission by those in emerging countries such as China, Brazil, India and Poland, the study found (see ‘Uneven contributions’).

    3
    Source: Global State of Peer Review 2018

    Scientists in emerging economies are more likely to accept requests for peer review and complete their reviews faster than those from established economies. But their reviews also tend to be shorter than those from colleagues in wealthy countries.

    The report says scientists from emerging economies might review less because editors’ networks and scientific are still largely centred in developed nations.

    In 2013–17, the United States contributed nearly 33% of peer reviews, and published 25.4% of articles worldwide. By contrast, emerging nations did 19% of peer reviews, and published 29% of all articles.

    China stood out — the country accounted for 13.8% of scientific articles during the period, but did only 8.8% of reviews. Even so, China overtook the United Kingdom in numbers of peer reviews conducted by its scientists in 2015, the study says.

    _________________________________________
    Peer review in numbers

    Data from the Global State of Peer Review report for 2013–17

    68.5 million hours spent reviewing globally each year

    16.4 days is the median review time

    5 hours is the median time spent writing each review

    477 words is the average length of review reports

    10% of reviewers are responsible for 50% of peer reviews

    41% of survey respondents see peer review as part of their job

    75% of journal editors say the hardest part of their job is finding willing reviewers

    71% of researchers decline review requests because the article is outside their area of expertise

    42% of researchers decline review requests because they are too busy

    39% of reviewers never received any peer-review training

    _________________________________________

    China’s inclusion of could skew the picture, says John Walsh, a sociologist at the Georgia Institute of Technology in Atlanta.

    He thinks the difference in peer-review activity between rich and poor nations is “actually surprisingly low”, considering the huge discrepancy in science funding and excellence. “China is the really dramatic case,” he says. “If you took China out, the picture would look different.”

    The study notes that the number of peer reviews from emerging nations grew by 193% in 2013–17. That’s not surprising, Walsh says, because peer review offers several perks to researchers, including — usually — a few months of free access to the journal and the opportunity to view the latest research before it gets published.

    Review requests

    The study’s main message, Preston says, is that scientists in emerging nations are keen to do peer review, but do not receive as many requests as their colleagues. This is despite the fact that journals find it increasingly difficult to get their articles peer-reviewed.

    This chimes with experience on the ground. Mohd Abas Shah, an entomologist at the ICAR Central Potato Research Station in Jalandhar, India, says he has published five articles in international journals, but has received only four peer-review requests throughout his whole career. “Peer review provides opportunity to develop a good reputation among colleagues and possible collaborations,” he says. “Fewer opportunities for peer review means missing out on that.”

    The solution, the study recommends, is for scientists to cast a wider net when looking for potential peer reviewers.

    But journal editors can also do their part by being more considerate of people’s language skills and by forming alliances with journals in emerging science regions, says Juan Corley, an ecologist at Argentina’s national agricultural-research institute in Buenos Aires, and editor of the International Journal of Pest Management.

    “We need to increase the number of editors and journal board members from developing economies,” he says. The study found that fewer than 4% of journal editors in its sample came from emerging economies.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

     
  • richardmitnick 5:03 am on August 15, 2018 Permalink | Reply
    Tags: , Nature Magazine, , ,   

    From Nature via U Wisconsin IceCube: “Special relativity validated by neutrinos” 

    U Wisconsin ICECUBE neutrino detector at the South Pole

    IceCube employs more than 5000 detectors lowered on 86 strings into almost 100 holes in the Antarctic ice NSF B. Gudbjartsson, IceCube Collaboration

    Lunar Icecube

    IceCube DeepCore annotated

    IceCube PINGU annotated


    DM-Ice II at IceCube annotated

    Nature Mag
    From Nature

    13 August 2018
    Matthew Mewes

    Neutrinos are tiny, ghost-like particles that habitually change identity. A measurement of the rate of change in high-energy neutrinos racing through Earth provides a record-breaking test of Einstein’s special theory of relativity.

    The existence of extremely light, electrically neutral particles called neutrinos was first postulated in 1930 to explain an apparent violation of energy conservation in the decays of certain unstable atomic nuclei. Writing in Nature Physics, the IceCube Collaboration1 now uses neutrinos seen in the world’s largest particle detector to scrutinize another cornerstone of physics: Lorentz invariance. This principle states that the laws of physics are independent of the speed and orientation of the experimenter’s frame of reference, and serves as the mathematical foundation for Albert Einstein’s special theory of relativity. Scouring their data for signs of broken Lorentz invariance, the authors carry out one of the most stringent tests of special relativity so far, and demonstrate how the peculiarities of neutrinos can be used to probe the foundations of modern physics.

    Physicists generally assume that Lorentz invariance holds exactly. However, in the late 1990s, the principle began to be systematically challenged2, largely because of the possibility that it was broken slightly in proposed theories of fundamental physics, such as string theory3. Over the past two decades, researchers have tested Lorentz invariance in objects ranging from photons to the Moon4.

    The IceCube Collaboration instead tested the principle using neutrinos. Neutrinos interact with matter through the weak force — one of the four fundamental forces of nature. The influence of the weak force is limited to minute distances. As a result, interactions between neutrinos and matter are extremely improbable, and a neutrino can easily traverse the entire Earth unimpeded. This poses a challenge for physicists trying to study these elusive particles, because almost every neutrino will simply pass through any detector completely unnoticed.

    The IceCube Neutrino Observatory, located at the South Pole, remedies this problem by monitoring an immense target volume to glimpse the exceedingly rare interactions. At the heart of the detector are more than 5,000 light sensors, which are focused on 1 cubic kilometre (1 billion tonnes) of ice. The sensors constantly look for the telltale flashes of light that are produced when a neutrino collides with a particle in the ice.

    The main goal of the IceCube Neutrino Observatory is to observe comparatively scarce neutrinos that are produced during some of the Universe’s most violent astrophysical events. However, in its test of Lorentz invariance, the collaboration studied more-abundant neutrinos that are generated when fast-moving charged particles from space collide with atoms in Earth’s atmosphere. There are three known types of neutrino: electron, muon and tau. Most of the neutrinos produced in the atmosphere are muon neutrinos.

    Atmospheric neutrinos generated around the globe travel freely to the South Pole, but can change type along the way. Such changes stem from the fact that electron, muon and tau neutrinos are not particles in the usual sense. They are actually quantum combinations of three ‘real’ particles — ν1, ν2 and ν3 — that have tiny but different masses.

    In a simple approximation relevant to the IceCube experiment, the birth of a muon neutrino in the atmosphere can be thought of as the simultaneous production of two quantum-mechanical waves: one for ν2 and one for ν3 (Fig. 1). These waves are observed as a muon neutrino only because they are in phase, which means the peaks of the two waves are seen at the same time. By contrast, a tau neutrino results from out-of-phase waves, whereby the peak of one wave arrives with the valley of the other.

    1
    Figure 1 | Propagation of neutrinos through Earth. There are three known types of neutrino: electron, muon and tau. a, A muon neutrino produced in Earth’s atmosphere can be thought of as the combination of two quantum-mechanical waves (red and blue) that are in phase — the peaks of the waves are observed at the same time. If a principle known as Lorentz invariance were violated, these waves could travel at different speeds through Earth’s interior and be detected in the out-of-phase tau-neutrino state. b, The IceCube Collaboration1 reports no evidence of such conversion, constraining the extent to which Lorentz invariance could be violated.

    If neutrinos were massless and Lorentz invariance held exactly, the two waves would simply travel in unison, always maintaining the in-phase muon-neutrino state. However, small differences in the masses of ν2 and ν3 or broken Lorentz invariance could cause the waves to travel at slightly different speeds, leading to a gradual shift from the muon-neutrino state to the out-of-phase tau-neutrino state. Such transitions are known as neutrino oscillations and enable the IceCube detector to pick out potential violations of Lorentz invariance. Oscillations resulting from mass differences are expected to be negligible at the neutrino energies considered in the authors’ analysis, so the observation of an oscillation would signal a possible breakdown of special relativity.

    The IceCube Collaboration is not the first group to seek Lorentz-invariance violation in neutrino oscillations [5–10]. However, two key factors allowed the authors to carry out the most precise search so far. First, atmospheric neutrinos that are produced on the opposite side of Earth to the detector travel a large distance (almost 13,000 km) before being observed, maximizing the probability that a potential oscillation will occur. Second, the large size of the detector allows neutrinos to be observed that have much higher energies than those that can be seen in other experiments.

    Such high energies imply that the quantum-mechanical waves have tiny wavelengths, down to less than one-billionth of the width of an atom. The IceCube Collaboration saw no sign of oscillations, and therefore inferred that the peaks of the waves associated with ν2 and ν3 are shifted by no more than this distance after travelling the diameter of Earth. Consequently, the speeds of the waves differ by no more than a few parts per 10^28 — a result that is one of the most precise speed comparisons in history.

    The authors’ analysis provides support for special relativity and places tight constraints on a number of different classes of Lorentz-invariance violation, many for the first time. Although already impressive, the IceCube experiment has yet to reach its full potential. Because of limited data, the authors restricted their attention to violations that are independent of the direction of neutrino propagation, neglecting possible direction-dependent violations that could arise more generally.

    With a greater number of neutrino detections, the experiment, or a larger future version [11], could search for direction-dependent violations. Eventually, similar studies involving more-energetic astrophysical neutrinos propagating over astronomical distances could test the foundations of physics at unprecedented levels.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

    IceCube is a particle detector at the South Pole that records the interactions of a nearly massless sub-atomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars. The IceCube telescope is a powerful tool to search for dark matter, and could reveal the new physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. IceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice.

     
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