Tagged: Niels Bohr Institute Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 5:43 pm on December 9, 2020 Permalink | Reply
    Tags: , "Researchers achieve quantum advantage", Niels Bohr Institute, , U Copenhagen [Københavns Universitet]   

    From U Copenhagen [Københavns Universitet] and Niels Bohr Institute (DK) via phys.org: “Researchers achieve quantum advantage” 

    From U Copenhagen [Københavns Universitet] (DK)

    Niels Bohr Institute bloc

    Niels Bohr Institute


    phys.org

    December 9, 2020

    1
    The team behind the new discovery from Niels Bohr Institute in Copenhagen, Denmark. Credit: Niels Bohr Institute.

    University of Copenhagen researchers have advanced their quantum technology to such a degree that classical computing technology can no longer keep up. They have developed a chip that, with financial backing, could be scaled up and used to build the quantum simulator of the future. Their results are now published in Science Advances.

    First came Google. Now, researchers at the University of Copenhagen’s Niels Bohr Institute in collaboration with University of Bochum have joined Google in the race to build the world’s first quantum computer with what they are calling a “major breakthrough.”

    “We now possess the tool that makes it possible to build a quantum simulator that can outperform a classical computer. This is a major breakthrough and the first step into uncharted territory in the world of quantum physics,” asserts Professor Peter Lodahl, Director of the Center for Hybrid Quantum Networks (Hy-Q).

    Specifically, the researchers developed a nanochip less than one-tenth the thickness of a human hair. The chip allows them to produce enough stable light particles, known as photons, encoded with quantum information to scale up the technology, and in so doing, may achieve what is known as ‘quantum advantage’: the state where a quantum device can solve a given computational task faster than the world’s most powerful supercomputer.

    While the researchers have yet to conduct an actual ‘quantum advantage’ experiment, their article in Science Advances proves that their chip produces a quantum mechanical resource that can be used to reach ‘quantum advantage’ with already demonstrated technology.

    To achieve this state demands that one can control about 50 quantum bits, “qubits”—quantum physics’ equivalent of the binary bits of zeros and ones used in our classical computers—in a comprehensive experimental set-up that is well beyond the university’s own financial means.

    “It could cost us 10 million Euro to perform an actual experiment that simultaneously controls 50 photons, as Google did it with superconducting qubits. We simply can’t afford that. However, what we as scientific researchers can do is to develop a photon source and prove that it can be used to achieve ‘quantum advantage.” We have developed the fundamental building block,” explains Assistant Professor Ravitej Uppu, lead author of the results.

    “In the meantime, we will use our photon sources to develop new and advanced quantum simulators to solve complex biochemical problems that might, for example, be used to develop new medicines. So, we are already preparing the next steps for the technology. Being at a university allows one to establish the foundation of a technology and demonstrate the possibilities, whereas definitive technology upscaling requires greater investment. We will work to establish a strong European consortium of academic and industrial partners with a focus on building photonic quantum simulators with ‘quantum advantage,'” continues Peter Lodahl.

    A bright future for upscaling quantum computers Various schools exist in the world of qubit development for quantum computers, depending upon which “quantum building blocks” one starts with: atoms, electrons, or photons. Each platform has pros and cons, and it remains difficult to predict, which technology will triumph.

    The primary advantage of light-based quantum computers is that technology is already available for scaling up to many qubits because of the availability of advanced photonic chips, which have been developed for the telecom industry. A major challenge to generating photon qubits has been to do so with sufficiently high quality. This is precisely where the Copenhagen researchers achieved their breakthrough.

    “Denmark and Europe have proud traditions in quantum optics research, and at the same time a strong telecom industry and infrastructure. It would be really exciting to combine these strengths in a large-scale initiative dedicated to photonic quantum computers. It would be fantastic to be part of a process that extends all the way from fundamental quantum physics to new technological applications,” says Peter Lodahl.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Niels Bohr Institute Campus

    Københavns Universitet (UCPH) [U Copenhagen] (DK)] is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge (UK), Yale University, The Australian National University (AU), and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 11:12 am on September 5, 2020 Permalink | Reply
    Tags: "Extracting order from a quantum measurement finally shown experimentally", , “Quantum drum”, , Extracting order from the largely disordered system., If we turn to quantum mechanics the world looks rather different and yet the same., Niels Bohr Institute, , , , The connection between thermodynamics and quantum measurements has been known for more than a century., The laws of thermodynamics cover extremely complicated processes., The laws of thermodynamics tell us that the disorder will in fact always increase-entropy.   

    From Niels Bohr Institute: “Extracting order from a quantum measurement finally shown experimentally” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    4 September 2020

    Professor Albert Schliesser
    albert.schliesser@nbi.ku.dk

    QUANTUM TECHNOLOGY: In physics, it is essential to be able to show a theoretical assumption in actual, physical experiments. For more than a hundred years, physicists have been aware of the link between the concepts of disorder in a system, and information obtained by measurement. However, a clean experimental assessment of this link in common monitored systems, that is systems which are continuously measured over time, was missing so far.

    1
    A thin silicon nitride membrane (white) is stretched tight across a silicon frame (red). The membrane contains a pattern of holes, with one small island in the center, whose vibrations are measured in the experiment.

    But now, using a “quantum drum”, a vibrating, mechanical membrane, researchers at the Niels Bohr Institute, University of Copenhagen, have realized an experimental setup that shows the physical interplay between the disorder and the outcomes of a measurement. Most importantly, these outcomes allow to extract order from the largely disordered system, providing a general tool to engineer the state of the system, essential for future quantum technologies, like quantum computers. The result is now published in as an Editors’ Suggestion in Physical Review Letters.

    Measurements will always introduce a level of disturbance of any system it measures. In the ordinary, physical world, this is usually not relevant, because it is perfectly possible for us to measure, say, the length of a table without noticing that disturbance. But on the quantum scale, like the movements of the membranes used in the Schliesser lab at the Niels Bohr Institute, the consequences of the disturbance made by measurements are huge. These large disturbances increase the entropy, or disorder, of the underlying system, and apparently preclude to extract any order from the measurement. But before explaining how the recent experiment realized this, the concepts of entropy and thermodynamics need a few words.

    Breaking an egg is thermodynamics.

    The law of thermodynamics covers extremely complicated processes. The classic example is that if an egg falls off of a table, it breaks on the floor. In the collision, heat is produced – among many other physical processes – and if you imagine you could control all of these complicated processes, there is nothing in the physical laws that say you can’t reverse the process. In other words, the egg could actually assemble itself and fly up to the table surface again, if we could control the behavior of every single atom, and reverse the process. It is theoretically possible. You can also think of an egg as an ordered system, and if it breaks, it becomes extremely disordered. Physicists say that the entropy, the amount of disorder, has increased. The laws of thermodynamics tell us that the disorder will in fact always increase, not the other way round: So eggs do not generally jump off floors, assemble and land on tables in the real world.

    Correct quantum system readouts are essential – and notoriously difficult to obtain.

    If we turn to quantum mechanics, the world looks rather different, and yet the same. If we continuously measure the displacement of a mechanical, moving system like the “membrane-drum” with a precision only limited by the quantum laws, this measurement disturbs the movement profoundly. So you will end up measuring a displacement which is disturbed during the measurement process itself, and the readout of the original displacement will be spoiled – unless you can measure the introduced disorder as well. In this case, you can use the information about the disorder to reduce the entropy produced by the measurement and generate order from it – comparable to controlling the disorder in the shattered egg-system. But this time we have the information on the displacement as well, so we have learnt something about the entire system along the way, and, crucially, we have access to the original vibration of the membrane, i.e. the correct readout.

    A generalized framework for understanding entropy in quantum systems.

    “The connection between thermodynamics and quantum measurements has been known for more than a century. However, an experimental assessment of this link was missing so far, in the context of continuous measurements. That is exactly what we have done with this experiment. It is absolutely essential that we understand how measurements produce entropy and disorder in quantum systems, and how we use it in order to have control over the readouts we shall have in the future from, say, a quantum system like a quantum computer. If we are not able to control the disturbances, we basically won’t be able to understand the readouts – and the quantum computer readouts will be illegible, and useless, of course”, says Massimiliano Rossi, PhD student and first author on the scientific article. “This framework is important in order to create a generalized basic foundation for our understanding of entropy producing systems on the quantum scale. That’s basically where this study fits into the grander scale of things in physics”.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 1:08 pm on August 31, 2020 Permalink | Reply
    Tags: , Approximately 40 per cent of terrestrial ecosystems are projected to have experienced shifts in temperature during the past 21000 years., Niels Bohr Institute, Studying locations in regions such as the Arctic; Eurasia; the Amazon; and New Zealand can yield knowledge of how climate has changed and how this has impacted plants and animals., The warming from the last ice age to our current interglacial period 11-18000 years ago Arctic temperatures have increased by more than 10 degrees Celsius., These shifts are similar in pace and magnitude to regional-scale future forecasts.,   

    From Niels Bohr Institute: “Knowledge about the past can preserve the biodiversity of tomorrow” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    31 August 2020

    Professor Dorthe Dahl-Jensen
    Mobile: +45 22 89 45 37
    E-mail: ddj@nbi.ku.dk

    Associate Professor Anders Svensson
    Mobile: 40 38 44 10
    E-mail: as@nbi.ku.dk

    Journalist Katherina Killander
    Mobile: +45 51 68 04 74
    E-mail: klu@science.ku.dk

    Climate change threatens plants and animals across the planet. Interdisciplinary research by, among others, climate and biodiversity researchers at the University of Copenhagen, has mapped responses of biodiversity caused by abrupt climate changes in the past. The findings can be used to protect both individual species and entire ecosystems in the warmer climates of the future and can strengthen effective conservation practice and policy.

    1

    Approximately 40 per cent of terrestrial ecosystems are projected to have experienced shifts in temperature during the past 21,000 years that are similar in pace and magnitude to regional-scale future forecasts.

    An international team of scientists led by researchers from the University of Copenhagen and University of Adelaide, has identified and examined past warming events similar to those anticipated in the coming decades, to better understand how species and ecosystems will cope.

    “Studying locations in regions such as the Arctic, Eurasia, the Amazon and New Zealand can yield knowledge of how climate has changed and how this has impacted plants and animals. Using advanced new methods, including the use of DNA to map biodiversity and precise methods for dating climate change, we have taken advantage of opportunities to find precise causalities. The past climate changes are similar to those that we expect in coming decades,” explains Professor Dorthe Dahl-Jensen.

    By mapping the prevalence of species using combined fossil data archives, researchers were able to see how individual plant and animal species — and entire ecosystems — have responded to historical temperature increases:

    “During large climate shifts of the past, such as the warming from the last ice age to our current interglacial period 11-18,000 years ago, Arctic temperatures have increased by more than 10 degrees Celsius. This is a warming of the same magnitude as the UN predicts can occur in the future, as is described in IPCC reports and forecasts,” says Professor Dorthe Dahl-Jensen.

    Researchers observed that some species, such as antelope, were able to migrate northward, while others, including the Arctic fox, became extinct in areas of what is now Russia. This knowledge can be used to predict how plants and animals will respond to future climate changes. During the last interglacial period — the Eemian Interglacial Stage, from 115-128,000 years ago — it was warmer, particularly in Arctic regions. During this time, the central Siberian tundra shifted 200 km northwards, hippos roamed England and giant turtles crawled lazily about the US Midwest.

    More accurate forecasts, based upon the past.

    The new knowledge compiled by researchers can be used to develop more accurate forecasts concerning which plant and animal species are being threatened with extinction. This in turn can allow for quicker intervention through international conservation measures. The knowledge also makes it possible to map robust ecosystems, which are less sensitive to climate change.

    “We have gained access to completely new knowledge about how ecosystems, plants and animals have responded to temperature increases similar to those that we are confronted with today and will be in the future. We can use this knowledge to be at the forefront of protecting and conserving biodiversity. It provides knowledge for us to protect the species that remain,” says Associate Professor Anders Svensson of the University of Copenhagen’s Niels Bohr Institute.

    “Conservation biologists are taking full advantage of the long-term history of the planet as recorded in paleo-archives, such as those gathered by the team, to understand biological responses to abrupt climate changes of the past, quantify trends, and develop scenarios of future biodiversity loss from climate change,” says the study’s main author, Damien Fordham, of the University of Adelaide and the University of Copenhagen’s Globe Institute.

    Research into the past demonstrates that many ecosystems are able to adapt to sudden climate change, even when migration is not an option. Thus, it is important to acquire more knowledge and ensure healthy interaction between the planners of future ecosystems and this historical knowledge. Historical archives also demonstrate that other factors, such as the impact of humans and the establishment of cities, the clearing of forests and changes to ecosystems, also have had a very significant impact on species extinction.

    Results just published in the journal Science.

    The research article illustrates how interdisciplinary research among climate and biodiversity researchers, and the deployment of new methods, better dating and climate models can be used to generate knowledge that will advance our ability to create and preserve ecosystems.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 12:47 pm on July 17, 2020 Permalink | Reply
    Tags: "Separating Gamma-Ray Bursts: Students Make Critical Breakthrough", , , , , , Niels Bohr Institute, Scientists at the Niels Bohr Institute have developed a method to classify all GRBs without needing to find an afterglow.   

    From Niels Bohr Institute- “Separating Gamma-Ray Bursts: Students Make Critical Breakthrough” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    17 July 2020
    Charles Louis Steinhardt, Associate professor
    The Cosmic Dawn Center
    Email: Steinhardt@nbi.ku.dk
    Phone: +45 35 33 50 10

    Gamma-Ray Bursts: By applying a machine-learning algorithm, scientists at the Niels Bohr Institute, University of Copenhagen, have developed a method to classify all gamma-ray bursts (GRBs), rapid highly energetic explosions in distant galaxies, without needing to find an afterglow – by which GRBs are presently categorized. This breakthrough, initiated by first-year B.Sc. students, may prove key in finally discovering the origins of these mysterious bursts. The result is now published in The Astrophysical Journal Letters.

    1
    The figure indicates how similar different GRBs are to each other. Points which are closer together are more similar, and points which are further away are more different. What we find is that there are two distinct groups, one orange and the other blue. The orange dots appear to correspond to “short” GRB, which have been hypothesized to be produced by mergers of neutron stars, and the blue dots appear to correspond to “long” GRB, which might instead be produced by the collapse of dying, massive stars.

    Ever since gamma-ray bursts (GRBs) were accidentally picked up by Cold War satellites in the 70s, the origin of these rapid bursts have been a significant puzzle. Although many astronomers agree that GRBs can be divided into shorter (typically less than 1 second) and longer (up to a few minutes) bursts, the two groups are overlapping. It has been thought that longer bursts might be associated with the collapse of massive stars, while shorter bursts might instead be caused by the merger of neutron stars. However, without the ability to separate the two groups and pinpoint their properties, it has been impossible to test these ideas.

    So far, it has only been possible to determine the type of a GRB about 1% of the time, when a telescope was able to point at the burst location quickly enough to pick up residual light, called an afterglow. This has been such a crucial step that astronomers have developed worldwide networks capable of interrupting other work and repointing large telescopes within minutes of the discovery of a new burst. One GRB was even detected by the LIGO Observatory using gravitational waves, for which the team was awarded the 2017 Nobel Prize.

    _________________________________________________

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project


    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research


    _________________________________________________

    Breakthrough achieved using machine-learning algorithm

    Now, scientists at the Niels Bohr Institute have developed a method to classify all GRBs without needing to find an afterglow. The group, led by first-year B.Sc. Physics students Johann Bock Severin, Christian Kragh Jespersen and Jonas Vinther, applied a machine-learning algorithm to classify GRBs. They identified a clean separation between long and short GRB’s. Their work, carried out under the supervision of Charles Steinhardt, will bring astronomers a step closer to understanding GRB’s.

    This breakthrough may prove the key to finally discovering the origins of these mysterious bursts. As Charles Steinhardt, Associate Professor at the Cosmic Dawn Center of the Niels Bohr Institute explains, “Now that we have two complete sets available, we can start exploring the differences between them. So far, there had not been a tool to do that.”

    3
    Artist’s impression of a gamma-ray burst. Credit: ESA, illustration by ESA/ECF

    From algorithm to visual map

    Instead of using a limited set of summary statistics, as was typically done until then, the students decided to encode all available information on GRB’s using the machine learning algorithm t-SNE. The t-distributed Stochastic neighborhood embedding algorithm takes complex high-dimensional data and produces a simplified and visually accessible map. It does so without interfering with the structure of the dataset. “The unique thing about this approach,” explains Christian Kragh Jespersen, “is that t-SNE doesn’t force there to be two groups. You let the data speak for itself and tell you how it should be classified.”

    Shining light on the data

    The preparation of the feature space – the input you give the algorithm – was the most challenging part of the project, says Johann Bock Severin. Essentially, the students had to prepare the dataset in such a way that its most important features would stand out. “I like to compare it to hanging your data points from the ceiling in a dark room,” explains Christian Kragh Jespersen. “Our main problem was to figure out from what direction we should shine light on the data to make the separations visible.”

    Step 0 in understanding GRB’s”

    The students explored the t-SNE machine-learning algorithm as part of their 1st Year project, a 1st year course in the Bachelor of Physics. “By the time we got to the end of the course, it was clear we had quite a significant result”, their supervisor Charles Steinhardt says. The students’ mapping of the t-SNE cleanly divides all GRB’s from the Swift observatory into two groups. Importantly, it classifies GRB’s that previously were difficult to classify. “This essentially is step 0 in understanding GRB’s,” explains Steinhardt. “For the first time, we can confirm that shorter and longer GRB’s are indeed completely separate things.”

    Without any prior theoretical background in astronomy, the students have discovered a key piece of the puzzle surrounding GRB’s. From here, astronomers can start to develop models to identify the characteristics of these two separate classes.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 5:01 pm on December 16, 2019 Permalink | Reply
    Tags: "Carbon cocoons surround growing galaxies far beyond previous beliefs says new study from the Niels Bohr Institute", , , , , , Niels Bohr Institute   

    From Niels Bohr Institute: “Carbon cocoons surround growing galaxies far beyond previous beliefs, says new study from the Niels Bohr Institute” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    16 December 2019

    Seiji Fujimoto, Postdoc
    Cosmic DAWN Center
    Vibenshuset, Lyngbyvej 2
    DK-2100 Copenhagen Ø
    Email: fujimoto@nbi.ku.dk

    Sune Toft, Professor
    Cosmic Dawn Center
    Vibenshuset, Lyngbyvej 2
    DK-2100 Copenhagen Ø
    Phone: + 45 61680930
    Email: sune@nbi.ku.dk

    Researchers have discovered gigantic clouds of gaseous carbon spanning more than a radius of 30,000 light-years around young galaxies using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    This is the first confirmation that carbon atoms produced inside of stars in the early Universe have spread beyond galaxies. No theoretical studies have predicted such huge carbon cocoons around growing galaxies, which raises questions about our current understanding of cosmic evolution. The result was obtained by Seiji Fujimoto and his colleagues, rather unconventionally, by examining data from former observations. He is currently employed at The Cosmic Dawn Center at the Niels Bohr Institute, University of Copenhagen. The study is now published in The Astrophysical Journal.

    1
    Artist´s impression of a young galaxy surrounded by a huge gaseous carbon cloud. Credit: NAOJ

    Combinations of archival data achieved unprecedented sensitivity

    “We examined the ALMA Science Archive thoroughly and collected all the data that contain radio signals from carbon ions in galaxies in the early Universe, only one billion years after the Big Bang,” says Seiji Fujimoto, the lead author of the research paper, and a former Ph.D. student at the University of Tokyo. “By combining all the data, we achieved unprecedented sensitivity. To obtain a dataset of the same quality with one observation would take 20 times longer than typical ALMA observations, which is almost impossible to achieve.”

    The discovery suggests rewriting parts of the evolution of the universe

    Heavy elements such as carbon and oxygen did not exist in the Universe at the time of the Big Bang. They were formed later by nuclear fusion in stars. However, it is not yet understood how these elements spread throughout the Universe. Astronomers have found heavy elements inside baby galaxies, but not beyond those galaxies, due to the limited sensitivity of their telescopes. This research team summed the faint signals stored in the data archive and pushed the limits.

    “The gaseous carbon clouds are almost five times larger than the distribution of stars in the galaxies, as observed with the Hubble Space Telescope,” explains Masami Ouchi, a professor at the University of Tokyo and the National Astronomical Observatory of Japan. “We spotted diffuse but huge clouds floating in the coal-black Universe.”

    2
    ALMA and NASA/ESA Hubble Space Telescope (HST) image of a young galaxy surrounded by a gaseous carbon cocoon. The red color shows the distribution of carbon gas imaged by combining the ALMA data for 18 galaxies. The stellar distribution photographed by HST is shown in blue. Credit: ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, Fujimoto et al.

    Then, how were the carbon cocoons formed?

    “Supernova explosions at the final stage of stellar life expel heavy elements formed in the stars,” says Professor Rob Ivison, the Director for Science at the European Southern Observatory. “Energetic jets and radiation from supermassive black holes in the centers of the galaxies could also help transport carbon outside of the galaxies and finally to throughout the Universe. We are witnessing this ongoing diffusion process, the earliest environmental pollution in the Universe.”

    New physical processes must be incorporated into existing models

    The research team notes that at present theoretical models are unable to explain such large carbon clouds around young galaxies, probably indicating that some new physical process must be incorporated into cosmological simulations. “Young galaxies seem to eject an amount of carbon-rich gas far exceeding our expectation,” says Andrea Ferrara, a professor at Scuola Normale Superiore di Pisa. Seiji Fujimoto adds that carbon is not the only element dispersed in the cocoon. Other elements such as Oxygen and Nitrogen could be detected as well, but the signals were fainter. This, however, indicates that other elements could be undergoing the same process as carbon. This is one of many points for further research, suggested by the study.

    The team is now using ALMA and other telescopes around the world to further explore the implications of the discovery for galactic outflows and carbon-rich halos around galaxies.

    There will ultimately be an ALMA article on this subject. When ALMA publishes, a blog post will be done with it. So far, there is only a press release which is incomplete.

    See the full article here .

    See the preliminary ALMA article here. If and when ALMA issues a full article, there will be a revision. This is based upon the press release. It is essentially complete.


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 11:24 am on October 25, 2019 Permalink | Reply
    Tags: "The final piece in the puzzle of the origin of the elements", , , , , , , , Niels Bohr Institute,   

    From Niels Bohr Institute: “The final piece in the puzzle of the origin of the elements” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    23 October 2019

    Darach Watson
    Cosmic Dawn Center (DAWN)
    Niels Bohr Institute
    University of Copenhagen
    Mobile: +45 24 80 38 25
    Email: darach@nbi.ku.dk

    Maria Hornbek
    Journalist
    SCIENCE Communication
    University of Copenhagen
    Mobile: +45 22 95 42 83
    Email: maho@science.ku.dk

    The first unequivocal evidence of where the heaviest elements were forged has now been found by a research group led by the University of Copenhagen. For the first time, an element heavier than iron has been clearly detected in the collision of two neutron stars, resolving one of the fundamental questions about the history of the universe.

    1
    Artist’s impression of merging neutron stars. Credit: University of Warwick/Mark Garlick

    Since the 1950s, we have known that hydrogen and helium were formed during the Big Bang, and that heavier elements up to iron are created by nuclear fusion in stars and when stars explode as supernovae. But iron is only no. 26 out of about 90 naturally occurring elements in the periodic table. Where the other elements heavier than iron came from has long been a mystery. For some time now we have known that some of them form in the envelopes of low-mass stars, so-called AGB stars. But only half of the elements heavier than iron are created this way. So where do the rest come from?

    Now a research team led by astrophysicist Darach Watson of the Niels Bohr Institute has, for the first time, found spectroscopic evidence that heavy elements are created in the explosion that happens when two neutron stars collide. The researchers have identified the metal strontium in a spectrum from a neutron star collision observed in 2017. The result is published in the scientific journal Nature.

    “Before this we were unable to identify any specific element created in a neutron star merger. There were strong indications and good circumstantial evidence that heavy elements were created in these events, but the unequivocal evidence was missing until now,” says astrophysicist Darach Watson of the Niels Bohr Institute at the University of Copenhagen, adding:

    “One of the most fundamental questions about the universe has been: where do the elements of the periodic table come from? You could say that this is the last piece of the puzzle of the formation of the elements.”

    3
    Grundstoffet strontium as synthetic crystals. Credit: Heinrich Pniok

    Unique stellar crash in 2017 helped the researchers.

    The only way to create substances heavier than iron is by a process called neutron capture, where neutrons penetrate an atomic nucleus – for example, an iron atom – which absorbs the neutrons, creating a new, heavier atomic nucleus and thus a new element. Neutron capture can be either fast or slow, in the so-called r-process (rapid) or s-process (slow). About half of the substances created by neutron capture are primarily formed by the r-process. Elements formed almost exclusively by the r-process are typically very heavy and near the end of the periodic table: gold, platinum, uranium.

    It is this rapid process whose location has never been established. In recent years, the scientific consensus has evolved toward the idea that much of the r-process happens when two neutron stars collide – but the definitive evidence has thus far been missing. The neutron star collision triggers a phenomenon called a kilonova, where a fraction of the neutron stars’ combined mass is released and spread into the universe in a giant explosion.

    The only time the phenomenon was well-observed was in August 2017, when two neutron stars collided in a galaxy approx. 140 million light years from Earth; a collision first discovered through its gravitational wave signature and then followed-up by observatories such as the European Southern Observatory (ESO) in the Atacama desert in Chile.

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo,

    The spectra gathered back then at ESO are what Darach Watson and his colleagues have been analyzing ever since. However, no one at the time was able to identify any specific elements. Using a so-called black body spectrum, Darach Watson and colleagues succeeded in reproducing the early spectra of that kilonova, in which the element strontium is prominent. Curiously, strontium is one of the lighter of the heavy elements, and this in itself is important:

    “It was thought that perhaps only the heaviest elements, such as uranium and gold, formed in neutron star mergers. Now we know that the lighter of the heavy elements are also created in these mergers. And so it tells us that neutron star collisions produce a broad range of the heavy elements, from the lightest to the very heaviest,” says astrophysicist and co-author Jonatan Selsing, who until recently was a postdoc at the Niels Bohr Institute.

    The researchers’ next step is to try to identify more elements in the spectra of the kilonova. If successful, they expect to find elements heavier than strontium – possibly barium and lanthanum.

    The research article is written by:

    Darach Watson (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Camilla J. Hansen (Max Planck Institute for Astronomy, Heidelberg, Germany),
    Jonatan Selsing (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Andreas Koch (Center for Astronomy of Heidelberg University, Germany),
    Daniele B. Malesani (DTU Space, National Space Institute, Technical University of Denmark, & Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Anja C. Andersen (Niels Bohr Institute, University of Copenhagen, Denmark),
    Johan P. U. Fynbo (Niels Bohr Institute & Cosmic Dawn Center, University of Copenhagen, Denmark),
    Almudena Arcones (Institute of Nuclear Physics, Technical University of Darmstadt, Germany & GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany),
    Andreas Bauswein (GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany & Heidelberg Institute for Theoretical Studies, Germany),
    Stefano Covino (Astronomical Observatory of Brera, Italy’s National Institute for Astrophysics, Milan, Italy),
    Aniello Grado (Capodimonte Astronomical Observatory, Italy’s National Institute for Astrophysics, Naples, Italy),
    Kasper E. Heintz (Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Reykjavík, Iceland & Cosmic Dawn Center, Niels Bohr Institute University of Copenhagen, Denmark),
    Leslie Hunt (Arcetri Astrophysical Observatory, Italy’s National Institute for Astrophysics, Florence, Italy),
    Chryssa Kouveliotou (Physics Department, The George Washington University, Washington DC, USA & Astronomy, Physics and Statistics Institute of Sciences Washington DC, USA),
    Giorgos Leloudas (DTU Space, National Space Institute, Technical University of Denmark, & Niels Bohr Institute, University of Copenhagen, Denmark),
    Andrew Levan (Radboud University, Nijmegen, the Netherlands & Department of Physics, University of Warwick, UK),
    Paolo Mazzali (Astrophysics Research Institute, Liverpool John Moores University, UK & Max Planck Institute for Astrophysics, Garching, Germany),
    Elena Pian (Astrophysics and Space Science Observatory of Bologna, Italy’s National Institute for Astrophysics, Bologna, Italy).

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 9:15 pm on September 16, 2019 Permalink | Reply
    Tags: 21st century alchemy, , , , Niels Bohr Institute,   

    From Niels Bohr Institute: “Quantum Alchemy: Researchers use laser light to transform metal into magnet” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    16 September 2019

    Mark Spencer Rudner
    Associate Professor
    Condensed Matter Physics
    Niels Bohr Institutet
    rudner@nbi.ku.dk

    Maria Hornbek
    Journalist
    The Faculty of Science
    maho@science.ku.dk
    +45 22 95 42 83

    CONDENSED MATTER PHYSICS: Pioneering physicists from the University of Copenhagen and Nanyang Technological University in Singapore have discovered a way to get non-magnetic materials to make themselves magnetic by way of laser light. The phenomenon may also be used to endow many other materials with new properties.

    1
    Mark Rudner, Niels Bohr Institute, University of Copenhagen

    2
    Asst Prof Justin Song Chien Wen

    The intrinsic properties of materials arise from their chemistry — from the types of atoms that are present and the way that they are arranged. These factors determine, for example, how well a material may conduct electricity or whether or not it is magnetic. Therefore, the traditional route for changing or achieving new material properties has been through chemistry.

    Now, a pair of researchers from the University of Copenhagen and Nanyang Technological University in Singapore have discovered a new physical route to the transformation of material properties: when stimulated by laser light, a metal can transform itself from within and suddenly acquire new properties.

    1

    “For several years, we have been looking into how to transform the properties of a matter by irradiating it with certain types of light. What’s new is that not only can we change the properties using light, we can trigger the material to change itself, from the inside out, and emerge into a new phase with completely new properties. For instance, a non-magnetic metal can suddenly transform into a magnet,” explains Associate Professor Mark Rudner, a researcher at the University of Copenhagen’s Niels Bohr Institute.

    He and colleague Justin Song of Nanyang Technological University in Singapore made the discovery that is now published in Nature Physics. The idea of using light to transform the properties of a material is not novel in itself. But up to now, researchers have only been capable of manipulating the properties already found in a material. Giving a metal its own ‘separate life’, allowing it to generate its own new properties, has never been seen before.

    By way of theoretical analysis, the researchers have succeeded in proving that when a non-magnetic metallic disk is irradiated with linearly polarized light, circulating electric currents and hence magnetism can spontaneously emerge in the disk.

    Researchers use so-called plasmons (a type of electron wave) found in the material to change its intrinsic properties. When the material is irradiated with laser light, plasmons in the metal disk begin to rotate in either a clockwise or counterclockwise direction. However, these plasmons change the quantum electronic structure of a material, which simultaneously alters their own behavior, catalyzing a feedback loop. Feedback from the plasmons’ internal electric fields eventually causes the plasmons to break the intrinsic symmetry of the material and trigger an instability toward self-rotation that causes the metal to become magnetic.

    Technique can produce properties ‘on demand’

    According to Mark Rudner, the new theory pries open an entire new mindset and most likely, a wide range of applications:

    “It is an example of how the interaction between light and material can be used to produce certain properties in a material ‘on demand’. It also paves the way for a multitude of uses, because the principle is quite general and can work on many types of materials. We have demonstrated that we can transform a material into a magnet. We might also be able to change it into a superconductor or something entirely different,” says Rudner. He adds:

    “You could call it 21st century alchemy. In the Middle Ages, people were fascinated by the prospect of transforming lead into gold. Today, we aim to get one material to behave like another by stimulating it with a laser.”

    Among the possibilities, Rudner suggests that the principle could be useful in situations where one needs a material to alternate between behaving magnetically and not. It could also prove useful in opto-electronics – where, for example, light and electronics are combined for fiber-internet and sensor development.

    The researchers’ next steps are to expand the catalog of properties that can be altered in analogous ways, and to help stimulate their experimental investigation and utilization.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 12:10 pm on July 24, 2019 Permalink | Reply
    Tags: , , , , , Niels Bohr Institute, , ,   

    From Niels Bohr Institute: “Probing the beginning of the Universe can soon be done more accurately” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    Measurement of the Cosmic Microwave Background radiation:

    In the Karoo desert in South Africa, scientists from all over the world plan to set up a huge array of telescopes – the Square Kilometer Array (SKA).


    SKA South Africa

    As many as 200 telescopes will be erected in the next decade, in order to achieve the highest possible precision in measuring radiation from the Universe.

    1
    Photograph of the SKA-MPG telescope for which the study was performed. The primary dish has a diameter of 15 meters and can receive signals between 1.7 and 3.5 Gigahertz. It is currently being installed in the South African Karoo desert. © South African Radio Astronomy Observatory (SARAO)

    Among the many scientific goals of the SKA are tests of Einstein’s relativity theory, probing the nature of Dark Energy, and studying the properties of our Galaxy, to name just a few. A team of researchers, amongst them Sebastian von Hausegger, who just finished as a PhD fellow in the Theoretical Particle Physics and Cosmology group of the Niels Bohr Institute, University of Copenhagen, has developed a plan to utilize the very first prototype, the SKA-MPG telescope, in the Karoo in a different way in the near future: the additional knowledge about our Galaxy which this telescope will bring can be used immediately for the study of the Cosmic Microwave Background (CMB), the earliest picture of our Universe. In a detailed study, they investigate the scientific potential of the SKA-MPG telescope – the prototype for those dishes which eventually should be built into the array is built by the German Max Planck Society – and demonstrate the huge advantage already this single dish will have for cosmology. This forecast was led by Aritra Basu from Bielefeld University and is now published in Monthly Notices of the Royal Astronomical Society.

    Separating the foreground from the background

    The Cosmic Microwave Background radiation (CMB) is the afterglow of the forming of our Universe.

    CMB per ESA/Planck

    ESA/Planck 2009 to 2013

    In this respect, it carries the fingerprint of how everything we know and are came to be. If analyzed correctly, it will tell us about the very early universe, perhaps including stories about gravitational waves generated by a process called inflation, the currently leading theory of the Universe’s beginning – obviously, we want to be able to study it as closely and accurately as possible.

    Inflation

    4
    Alan Guth, from Highland Park High School and M.I.T., who first proposed cosmic inflation

    HPHS Owls

    Lambda-Cold Dark Matter, Accelerated Expansion of the Universe, Big Bang-Inflation (timeline of the universe) Date 2010 Credit: Alex MittelmannColdcreation

    Alan Guth’s notes:

    Alan Guth’s original notes on inflation

    However, all measurements we attempt to take of the CMB are disturbed by the radiation emitted by our own Galaxy. This radiation is called `foreground emission’ in the CMB community, to distinguish it from the sought-for cosmic `background’. To reliably remove thisforeground, we must understand exactly what it is, and what is causing it. This is where telescopes like the one shown come into play.

    Sebastian von Hausegger’s work as a PhD student dealt with the problem of foreground separation. “Essentially, you take a picture of the sky at different frequencies, and by tracing the differences of those pictures, you understand what sort of foreground emission they contain. Once that is done properly, the real work with interpreting the background can begin”, Sebastian explains. “The more frequencies you take pictures at – the better your understanding gets of the physical processes, the structure, and the composition of the Milky Way!” The SKA-MPG telescope is able to measure at 2048 different frequencies between 1.7 and 3.5 GHz – many more than previously possible.

    Bringing the radio astronomy and the CMB community together

    Sebastian continues, “The radio emission of our Galaxy is mainly caused by electrons, zooming around in the Galactic disk, and they can do crazy things. As a part of my PhD, I visited the Astroparticle Physics and Cosmology group at Bielefeld University, Germany. The group includes experts on galactic radio emission – the emission we call foreground radiation. I visited them as a representative from the CMB research community, so to say. Our own Galaxy is not that interesting in the grand scale of things, but the insight gained from measurements of its emission can sure help us learn about this grand scale! In this collaboration,we tried to bring the two communities closer together.”

    Motivated by the properties of the telescope, the authors of this study consider a much more ambitious model for the radio-foregrounds than was done in previous efforts. Even considering the impact of the SKA-MPG prototype alone, the level of achievable detail is much higher than with current data and the inferred prospects for CMB analyses are highly promising.

    An array of up to 200 telescopes is the goal

    The ambition of the Square Kilometer Array is to finally place 200 telescopes in the South African desert. The reason for choosing a remote area like a desert for performing their measurements the restriction of radio emission in the surroundings(the Karoo desert has been made a so-called Radio Quiet Zone). The large number of telescopes will give the SKA unprecedented precision. “As we speak, the prototype telescope is being built, and is expected to be completed in the autumn. It will be very interesting to see what the data will tell us, once it is up – not to mention the future data of the entire array”, says Sebastian.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
  • richardmitnick 4:25 pm on July 16, 2019 Permalink | Reply
    Tags: , , , , Niels Bohr Institute, ,   

    From U Wisconsin IceCube Collaboration: A Flock of Articles on NSF Grant to Upgrade IceCube 

    U Wisconsin ICECUBE neutrino detector at the South Pole

    From From U Wisconsin IceCube Collaboration

    From U Wisconsin: “UW lab gears up for another Antarctic drilling campaign”

    With news that the National Science Foundation (NSF) and international partners will support an upgrade to the IceCube neutrino detector at the South Pole, the UW–Madison lab that built the novel drill used to bore mile-deep holes in the Antarctic ice is gearing up for another drilling campaign.

    The UW’s Physical Sciences Laboratory (PSL), which specializes in making customized equipment for UW–Madison researchers, will once again lead drilling operations. The $37 million upgrade announced this week (July 16, 2019) will expand the IceCube detector by adding seven new strings of 108 optical modules each to study the basic properties of neutrinos, phantom-like particles that emanate from black holes and exploding stars, but that also cascade through Earth’s atmosphere as a result of colliding subatomic particles.

    1
    “It takes a crew of 30 people to run this 24/7. It’s the people that make it work,” says Bob Paulos, director of the Physical Sciences Lab. Photo: Bryce Richter

    See the full article here .

    From U Wisconsin: “IceCube: Antarctic neutrino detector to get $37 million upgrade”

    2
    The IceCube Neutrino Observatory is located at NSF’s Amundsen-Scott South Pole Station. Management and operation of the observatory is through the Wisconsin IceCube Particle Astrophysics Center at UW–Madison. Raffaela Busse, IceCube / NSF

    IceCube, the Antarctic neutrino detector that in July of 2018 helped unravel one of the oldest riddles in physics and astronomy — the origin of high-energy neutrinos and cosmic rays — is getting an upgrade.

    This month, the National Science Foundation (NSF) approved $23 million in funding to expand the detector and its scientific capabilities. Seven new strings of optical modules will be added to the 86 existing strings, adding more than 700 new, enhanced optical modules to the 5,160 sensors already embedded in the ice beneath the geographic South Pole.

    The upgrade, to be installed during the 2022–23 polar season, will receive additional support from international partners in Japan and Germany as well as from Michigan State University and the University of Wisconsin–Madison. Total new investment in the detector will be about $37 million.

    See the full article here .

    From Niels Bohr Institute: “A new Upgrade for the IceCube detector”

    3
    Illustration of the IceCube laboratory under the South Pole. The sensors detecting neutrinos are attached to the strings lowered into the ice. The upgrade will take place in the Deep Core area. Illustration: IceCube/NSF

    Neutrino Research:

    The IceCube Neutrino Observatory in Antarctica is about to get a significant upgrade. This huge detector consists of 5,160 sensors embedded in a 1x1x1 km volume of glacial ice deep beneath the geographic South Pole. The purpose of the installation is to detect neutrinos, the “ghost particles” of the Universe. The IceCube Upgrade will add more than 700 new and enhanced optical sensors in the deepest, purest ice, greatly improving the observatory’s ability to measure low-energy neutrinos produced in the Earth’s atmosphere. The research in neutrinos at the Niels Bohr Institute, University of Copenhagen is led by Associate Professor Jason Koskinen

    See the full article here .

    From Michigan State University: “Upgrade for neutrino detector, thanks to NSF grant”

    5
    The IceCube Neutrino Observatory, the Antarctic detector that identified the first likely source of high-energy neutrinos and cosmic rays, is getting an upgrade. Courtesy of IceCube

    The IceCube Neutrino Observatory, the Antarctic detector that identified the first likely source of high-energy neutrinos and cosmic rays, is getting an upgrade.

    The National Science Foundation is upgrading the IceCube detector, extending its scientific capabilities to lower energies, and bridging IceCube to smaller neutrino detectors worldwide. The upgrade will insert seven strings of optical modules at the bottom center of the 86 existing strings, adding more than 700 new, enhanced optical modules to the 5,160 sensors already embedded in the ice beneath the geographic South Pole.

    The upgrade will include two new types of sensor modules, which will be tested for a ten-times-larger future extension of IceCube – IceCube-Gen2. The modules to be deployed in this first extension will be two to three times more sensitive than the ones that make up the current detector. This is an important benefit for neutrino studies, but it becomes even more relevant for planning the larger IceCube-Gen2.

    The $37 million extension, to be deployed during the 2022-23 polar field season, has now secured $23 million in NSF funding. Last fall, the upgrade office was set up, thanks to initial funding from NSF and additional support from international partners in Japan and Germany as well as from Michigan State University and the University of Wisconsin-Madison.

    See the full article here .

    From U Wisconsin IceCube: “The IceCube Upgrade: An international effort”

    The IceCube Upgrade project is an international collaboration made possible not only by support from the National Science Foundation but also thanks to significant contributions from partner institutions in the U.S. and around the world. Our national and international collaborators play a huge role in manufacturing new sensors, developing firmware, and much more. Learn more about a few of our partner institutions below.

    8
    The Chiba University group poses with one of the new D-Egg optical detectors. Credit: Chiba University

    Chiba University is responsible for the new D-Egg optical detectors, 300 of which will be deployed on the new Upgrade strings. A D-Egg is 30 percent smaller than the original IceCube DOM, but its photon detection effective area is twice as large thanks to two 8-inch PMTs in the specially designed egg-shaped vessel made of UV-transparent glass. Its up-down symmetric detection efficiency is expected to improve our precision for measuring Cherenkov light from neutrino interactions. The newly designed flasher devices in the D-Egg will also give a better understanding of optical characteristics in glacial ice to improve the resolution of arrival directions of cosmic neutrinos.

    See the full article here .

    From DESY: “Neutrino observatory IceCube receives significant upgrade”

    6
    Deep down in the perpetual ice of Antarctica IceCube watches out for a faint bluish glow that indicates a rare collision of a cosmic neutrino within the ice. Artist’s concept: DESY, Science Communication Lab

    Particle detector at the South Pole will be expanded to comprise a neutrino laboratory

    The international neutrino observatory IceCube at the South Pole will be considerably expanded in the coming years. In addition to the existing 5160 sensors, a further 700 optical modules will be installed in the perpetual ice of Antarctica. The National Science Foundation in the USA has approved 23 million US dollars for the expansion. The Helmholtz Centres DESY and Karlsruhe Institute of Technology (KIT) are supporting the construction of 430 new optical modules with a total of 5.7 million euros (6.4 million US dollars), which will turn the observatory into a neutrino laboratory. IceCube, for which Germany with a total of nine participating universities and the two Helmholtz Centres is the most important partner after the USA, had published convincing indications last year of a first source of high-energy neutrinos from the cosmos.

    See the full article here .

    See the full articles above .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition
    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.

    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

     
  • richardmitnick 8:52 am on April 12, 2019 Permalink | Reply
    Tags: , , , , Greenland Telescope will join the EHT by moving to the summit of the Greenland ice sheet summit of 3000 ft, Niels Bohr Institute, ,   

    From Niels Bohr Institute at University of Copenhagen: “Greenland Telescope to image black holes by moving onto the Greenland ice sheet” 

    University of Copenhagen

    Niels Bohr Institute bloc

    From Niels Bohr Institute

    10 April 2019

    Marianne Vestergaard
    Associate Professor, DARK, Niels Bohr Institute, University of Copenhagen
    mvester@nbi.ku.dk
    Phone: +45 35 32 59 09

    Scientists from the Niels Bohr Institute, University of Copenhagen, will soon be able to participate in the “Event Horizon Telescope” (EHT) with the Greenland Telescope (GLT). The GLT will become part of a global network of radio telescopes designed to get the first images of black holes.

    1
    NRAO/CfA Greenland Telescope will be moved to the Summit of the ice sheet during the summer of 2021, reaching an altitude of approx. 3000 meters above sea level, where the clear, dry and cold climate will offer better observing conditions. Photo: Greenlandtelescope.dk

    How do you take a picture of something that emits no light?

    It’s hard to get an image of a black hole. They are the darkest objects in the universe because their gravity is so intense that no light can escape them, and their tremendous density makes them very small in spite of their enormous mass. To overcome these problems, the experiment is targeting much larger black holes than normal, namely so-called supermassive black holes, millions or billions of times more massive than the sun, as well as distributing the network of telescopes across the Globe to maximise the resolution of the image. It is possible to detect the black hole because the EHT can image the “shadow” of the black hole against a bright background of hot material near it.

    While black holes have been theoretically expected for the best part of a century, the first conclusive evidence for the existence of black holes was only obtained in 2015, when gravitational waves from a merger of two (smaller) black holes were detected. However, so far, no one has ever managed to get an image of a black hole because they are so small and so dark. In the center of almost every galaxy in the Universe there is a compact and supermassive object that astronomers believe to be supermassive black holes, vastly more massive than the merging black holes detected in 2015. But the final evidence is still lacking that these concentrations of mass in the hearts of galaxies are actually black holes. By detecting and creating an image of the black hole, viewed in contrast against the powerful radiation from the gas being drawn into the hole, researchers can confirm that the compact object doesn’t have a surface to reflect any light, and that light behaves in the warped way that we expect from the theory of general relativity near a black hole and its strong gravitational field.

    [Supermassive black hole at Messier 87 was successfully imaged by the Event Horizon Telescope in 2107

    2

    In April of 2017, all 8 of the telescopes/telescope arrays associated with the Event Horizon Telescope pointed at Messier 87. This is what a supermassive black hole looks like, where the event horizon is clearly visible. Event Horizon Telescope collaboration et al.]

    Danish access to the data EHT will be producing

    A press conference was held at DTU Space on Wednesday 10. April, where the first results from the EHT consortium were presented. With the addition of the Greenland Telescope, the precision and sensitivity of the images will substantially increase, and at the same time, Danish researchers will gain access to the EHT.

    “ It is fascinating to know that our generation is not only the first to learn, via detections of gravitational waves, that black holes really exist. We will also be the first to see what they look like!” says Marianne Vestergaard, associate professor at DARK, the Niels Bohr Institute and she continues: “We, the researchers, are thrilled. These excellent results from the Event Horizon Telescope show us the remarkable things that a dedicated, global collaboration can achieve, and it reveals the great potential there is for exploring the complex parts of our universe of which black holes are a manifest. It is particularly enjoyable that we, the Danish researchers, will be able to contribute to this new type of telescope on the front line.

    The Summit of the icecap will be the new home for the Greenland Telescope

    Greenland Telescope will be moved to the Summit of the ice sheet, reaching an altitude of approx. 3000 meters above sea level. The air is much drier, and the clear, dry and cold climate will offer better observing conditions compared to the humid air along the coast. The complicated task of moving the telescope across the ice is planned to take place during the summer of 2021. Researchers from the Niels Bohr Institute’s Physics of Ice, Climate and Earth section are assisting in that operation.

    See the full article here .


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


    Stem Education Coalition

    Niels Bohr Institute Campus

    Niels Bohr Institute (Danish: Niels Bohr Institutet) is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the University of Copenhagen, by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institute.[1] Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.[2]

    During the 1920s, and 1930s, the Institute was the center of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institute.

    The University of Copenhagen (UCPH) (Danish: Københavns Universitet) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge, Yale University, The Australian National University, and UC Berkeley, amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: