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  • richardmitnick 10:57 am on April 24, 2019 Permalink | Reply
    Tags: "We Just Got The Best Evidence Yet of an Exotic 'Supersolid' State of Matter", , BECs-Bose–Einstein condensates, , , Researchers worked with two such quantum gases producing BECs of isotopes of erbium (erbium-166) and dysprosium (dysprosium-164), Science Alert, , Supersolids   

    From Science Alert: “We Just Got The Best Evidence Yet of an Exotic ‘Supersolid’ State of Matter” 


    From Science Alert

    24 APR 2019

    (Uni Innsbruck)

    Scientists have observed the clearest evidence yet of an incredibly rare and exotic theoretical phase of matter called a supersolid – and while it only lasted experimentally for a fleeting instant in the lab, it’s the longest we’ve ever glimpsed such paradoxical strangeness to exist at all.

    Supersolids were first theoretically predicted to exist a half-century ago, fusing both the rigid characteristics of solids and the flowing characteristics of liquids at the atomic level.

    What this means is that somehow, as impossible as it sounds, the atoms that make up these strange supersolid materials are spatially arranged in such a way that they resemble a crystalline structure, while simultaneously embodying the liquid-like properties of superfluidity.

    Scientists have been studying supersolid matter for decades, both theoretically but also experimentally, trying to replicate and somehow observe them in the real world, mostly in experiments with an isotope of helium called superfluid helium-4.

    However, despite many attempts – including a purported breakthrough in 2004 – firm proof for a helium-based supersolid still remains elusive.

    But there’s another way of potentially tricking supersolids into existence, with more recent attempts centred around ultra-cold quantum gases such as Bose–Einstein condensates (BECs). In these condensates, particles that make up the gas become so cold, they begin to show supersolid behaviour.

    “Recent experiments have revealed that such gases exhibit fundamental similarities with superfluid helium,” says experimental physicist Lauriane Chomaz from the University of Innsbruck in Austria, the first author of a new paper on this research.

    “These features lay the groundwork for reaching a state where the several tens of thousands of particles of the gas spontaneously organise in a self-determined crystalline structure while sharing the same macroscopic wavefunction – hallmarks of supersolidity.”

    In the new experiments, Chomaz and fellow researchers worked with two such quantum gases, producing BECs of isotopes of erbium (erbium-166) and dysprosium (dysprosium-164).

    Both of these gases are remarkable for featuring strong dipolar interactions, which, when tweaked sufficiently by ultra-cold temperatures, promotes atomic grouping into ‘droplet’ formations that themselves promote supersolidity.

    “For several years, researchers have known these BECs have the ingredients for supersolidity,” quantum researcher Tobias Donner from ETH Zürich, who wasn’t involved with the study, explains in a Physics overview piece.

    “First, they are superfluids. And second, under certain conditions, the atoms will segregate into several dense droplets, providing the necessary density modulation.”

    Although erbium-166 and dysprosium-164 are both good candidates for inducing supersolid behaviour, the team’s results showed the two gases are not equal.

    In the experiments with the erbium isotope, the supersolid state observed was “only transient”, senior researcher Francesca Ferlaino explains; in contrast, the dysprosium BEC demonstrated “unprecedented stability” for a supersolid.

    “Reaching the phases via a slow interaction tuning, starting from a stable condensate, we observe that erbium-166 and dysprosium-164 exhibit a striking difference in the lifetime of the supersolid properties, due to the different atom loss rates in the two systems,” the authors write in their paper.

    “Indeed, while in erbium-166 the supersolid behaviour survives only a few tens of milliseconds, we observe coherent density modulations for more than 150 ms in dysprosium-164.”

    Of course, 150 milliseconds might not seem very long to you and me, but for an incredibly exotic and quasi-impossible phase of matter that has to be coaxed into existence to be seen at all, it’s actually “remarkably long-lived”, to quote the research team.

    Despite that long life, the researchers stop short of proclaiming these results offer the unambiguous proof of supersolidity we’ve been looking for, describing the work as “evidence for hallmarks of this exotic state in ultracold dilute atomic gases”.

    That said, it’s clear we’re edging ever closer to even more exciting breakthroughs, especially since this research follows close on the heels of two other very recent experiments [Physical Review X] [Physical Review Letters] honing in on supersolid states in dipolar quantum gases.

    For solid proof of the supersolid, it may only be a matter of time.

    The findings are reported in Physical Review X.

    See the full article here .


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  • richardmitnick 8:46 am on April 18, 2019 Permalink | Reply
    Tags: "The First Molecular Bond in The Universe Has Finally Been Detected in Space", , , , , , Helium hydride ion HeH+ in the planetary nebula NGC 7027, , Science Alert   

    From NASA/DLR SOFIA via Science Alert: “The First Molecular Bond in The Universe Has Finally Been Detected in Space” 


    NASA SOFIA Banner




    Science Alert

    17 APR 2019

    NGC 7027 (Hubble/NASA/ESA/Judy Schmidt)

    After decades of searching, scientists have finally detected in space the first molecular bond that would have formed in the early Universe after the Big Bang.

    The unambiguous discovery of the helium hydride ion HeH+ in the planetary nebula NGC 7027 brings to a close an epic hunt to locate the elusive molecule in outer space, and cements theoretical predictions of the chemistry that essentially makes the Universe as we know it possible.

    “The lack of evidence of the very existence of helium hydride in the local Universe has called into question our understanding of the chemistry in the early Universe,” astronomer Rolf Güsten told ScienceAlert.

    “The detection reported now resolves such doubts.”

    Once the early Universe cooled down following the Big Bang almost 14 billion years ago, theory suggests that the ions of light elements began to recombine with one another.

    At a temperature somewhere below 4,000 Kelvin, the early Universe bore witness to what researchers say was the dawn of chemistry, and the whole process – according to science – depended on one pivotal step.

    “In this metal-free and low-density environment, neutral helium atoms formed the Universe’s first molecular bond in the helium hydride ion HeH+ through radiative association with protons,” Güsten and fellow researchers explain in a new paper [Nature].

    On an understandably smaller scale, scientists replicated the basic chemistry in the lab almost as far back as a century ago – but one considerable hurdle remained.

    That hurdle was that helium hydride – this most elementary of elementary compounds – was never seen in the wild. By wild, we mean space, and by space, we mean planetary nebulae.

    Planetary nebulae are glowing, expanding clouds of ionised gas that are expelled in the last stages of a star’s life – and they’re one of the closest astronomical analogues we have for post-Big Bang chemistry, at least as far as HeH+ is concerned.

    Scientists predicted HeH+ might form in planetary nebulae back in the 1970s, but up until now we’d still never been able to detect it.

    According to the researchers, that’s because Earth’s atmosphere is essentially a brick wall for ground-based spectrometers trying to perceive the molecule at the specific infra-red wavelength where it would be viewable.

    In addition, previous technological limitations in comparative low-resolution spectrometry made any observations of HeH+ ambiguous at best.

    Güsten’s team was able to overcome these two barriers in unison, thanks to the capabilities of the German Receiver for Astronomy at Terahertz Frequencies (GREAT) when flown aboard NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) aircraft.

    According to Güsten, GREAT is the only instrument worldwide that can perform these kinds of observations, and it would only ever be capable of seeing helium hydride in space if it were airborne first.

    “One cannot perform this search from ground-based observatories because at [the] 149 μm wavelength, Earth’s atmosphere is totally opaque,” Güsten says.

    “So you need to go into space or operate your instrument from a high-flying platform like SOFIA, cruising above the absorbing lower atmosphere.”

    And that’s what they did.

    Over three flights in May 2016, the team used their high-resolution spectrometer to observe the planetary nebula NGC 7027, and the readings gave the scientists exactly what they were looking for: the first unambiguous signal of the first ever molecule in space (after the Big Bang at least).

    Güsten says, with the new NGC 7027 results in hand, we can now put constraints on the chemical reactions that control the formation and destruction of the helium hydride molecule.

    “The respective rates are difficult to measure/to calculate, and in the literature have changed by factor of 10 in recent years,” Güsten told ScienceAlert.

    “Our observations will help to ‘calibrate’ these rates, and this will feed-back into the chemical ‘networks’ of the early Universe.”

    NASA SOFIA GREAT [German Receiver for Astronomy at Terahertz Frequencies]

    NASA SOFIA High-resolution Airborne Wideband Camera-Plus HAWC+ Camera

    NASA/SOFIA Forcast

    See the full article here .


    Please help promote STEM in your local schools.

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    SOFIA is a Boeing 747SP jetliner modified to carry a 106-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center, DLR. NASA’s Ames Research Center in California’s Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is maintained and operated from NASA’s Armstrong Flight Research Center Hangar 703, in Palmdale, California.
    NASA image

    DLR Bloc

  • richardmitnick 9:12 am on April 17, 2019 Permalink | Reply
    Tags: , , , Science Alert, , Z-pinch   

    From University of Washington via Science Alert: “Researchers Just Demonstrated Nuclear Fusion in a Device Small Enough to Keep at Home” 

    U Washington

    From University of Washington



    Science Alert

    17 APR 2019


    When it comes to the kinds of technology needed to contain a sun, there are currently just two horses in the race. Neither is what you’d call ‘petite’.

    An earlier form of fusion technology that barely made it out of the starting blocks has just overcome a serious hurdle. It’s got a long way to catch up, but given its potential cost and versatility, a table-sized fusion device like this is worth watching out for.

    While many have long given up on an early form of plasma confinement called the Z-pinch as a feasible way to generate power, researchers at the University of Washington in the US have continued to look for a way to overcome its shortcomings.

    A laboratory scale z-pinch device in operation with a Hydrogen plasma. Sandpiper at English Wikipedia

    Fusion power relies on clouds of charged particles you can squeeze the literal daylights out of – it’s the reaction that powers that big ball of hot gas we call the Sun.

    But containing a buzzing mix of superhot ions is extremely challenging – in the lab, scientists use intense magnetic fields for this task. Tokamaks like China’s Experimental Advanced Superconducting Tokamak reactor swirl their insanely hot plasma in such a way that they generate their own internal magnetic fields, helping contain the flow.

    China’s Experimental Advanced Superconducting Tokamak reactor (EAST)

    This approach gets the plasma cooking enough for it to release a critical amount of energy. But what it gains in generating heat it loses in long-term stability.

    Stellerators like Germany’s Wendelstein 7-X, on the other hand, rely more heavily on banks of externally applied magnetic fields. While this makes for better control over the plasma, it also makes it harder to reach the temperatures needed for fusion to occur.

    Wendelstein 7-AS built in built in Greifswald, Germany

    Both are making serious headway in our march towards fusion power. But those doughnuts holding the plasma are at least a few metres (a dozen feet) across, surrounded by complex banks of delicate electronics, making it unlikely we’ll see them shrink to a home or mobile version any time soon.

    In the early days of fusion research, a somewhat simpler method for squeezing a jet of plasma was to ‘pinch’ it through a magnetic field.

    A relatively small device known as a zeta or ‘Z’-pinch uses the specific orientation of a plasma’s internal magnetic field to apply what’s known as the Lorentz force to the flow of particles, effectively forcing its particles together through a bottleneck.

    In some sense, the device isn’t unlike a miniature version of its tokamak big brother. As such, it also suffers from similar stability issues that can cause its plasma to jump from the magnetic tracks and crash into the sides of its container.

    In fact, iterations of the Z-pinch led to the chunky tokamak technology that superseded it. Given this major limitation, the Z-pinch has all but become a relic of history.

    Hope remains that by going back to the roots of fusion, researchers might find a way to generate power without the need for complicated banks of surrounding machinery and magnets.

    Now, researchers from the University of Washington have found an alternative approach to stabilising the plasma in a Z-pinch not only works, but it can be used to generate a burst of fusion.

    To prevent the distortions in the plasma that cause it to escape the confines of its magnetic cage, the team manages the flow of the particles by applying a bit of fluid dynamics.

    Introducing what is known as sheared axial flow to a short column of plasma has previously been studied as a potential way to improve stability in a Z-pinch, to rather limited effect.

    Not to be deterred, physicists relied on computer simulations to show the concept was possible.

    Using a mix of 20 percent deuterium and 80 percent hydrogen, the team managed to hold stable a 50 centimetre (1.6 foot) long column of plasma enough to achieve fusion, evidenced by a signature generation of neutrons being emitted.

    We’re only talking 5 microseconds worth of neutrons here, so don’t clear space in your basement for your Z-Pinch 3000 Home Fusion Box quite yet. But the stability was 5,000 times longer than you’d expect without such a method being used, showing the principle is ripe for further study.

    Generating clean, abundant fusion energy is still a dream we’re all holding onto. A new approach to a less complex form of plasma technology could help remove at least some of the obstacles, if not prove to be a cheaper, more compact source of clean power in its own right.

    The race towards the horizon of limitless energy production is only just warming up, folks. And it really can’t come soon enough.

    This research was published in Physical Review Letters.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

  • richardmitnick 11:13 am on April 16, 2019 Permalink | Reply
    Tags: "Astronomers Have Found Potential Life-Supporting Conditions on The Nearest Exoplanet", , , , Carl Sagan Institute, , , , Science Alert   

    From Carl Sagan Institute via Science Alert: “Astronomers Have Found Potential Life-Supporting Conditions on The Nearest Exoplanet” 

    From Carl Sagan Institute



    Science Alert

    16 APR 2019

    Artist impression of an exoplanet from its moon. (IAU/L. Calçada)

    In August of 2016, astronomers from the European Southern Observatory (ESO) announced the discovery of an exoplanet in the neighboring system of Proxima Centauri. The news was greeted with considerable excitement, as this was the closest rocky planet to our Solar System that also orbited within its star’s habitable zone.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    Since then, multiple studies have been conducted to determine if this planet could actually support life.

    Unfortunately, most of the research so far has indicated that the likelihood of habitability are not good. Between Proxima Centauri’s variability and the planet being tidally-locked with its star, life would have a hard time surviving there.

    However, using lifeforms from early Earth as an example, a new study [MNRAS] conducted by researchers from the Carl Sagan Institute (CSI) has shows how life could have a fighting chance on Proxima b after all.

    Artist’s impression of Proxima b’s surface, orbiting the red dwarf star. (ESO)

    The study, which recently appeared in the Monthly Notices of the Royal Astronomical Society [link is above], was conducted by Jack O’Malley-James and Lisa Kaltenegger – an research associate and the director of the Carl Sagan Institute at Cornell University.

    Together, they examined the levels of surface UV flux that planets orbiting M-type (red dwarf) stars would experience and compared that to conditions on primordial Earth.

    The potential habitability of red dwarf systems is something scientists have been debated for decades. On the one hand, they have a number of attributes that are encouraging, not the least of which is their commonality.

    Essentially, red dwarfs are the most common type of star in the Universe, accounting for 85 percent of the stars in the Milky Way alone.

    They also have the greatest longevity, with lifespans that can last into the trillions of years. Last, but not least, they appear to be the most likely stars to host systems of rocky planets.

    This is attested to by the sheer number of rocky planets discovered around neighboring red dwarf stars in recent years – such as Proxima b, Ross 128b, LHS 1140b, Gliese 667Cc, GJ 536, the seven rocky planets orbiting TRAPPIST-1.

    A size comparison of the planets of the TRAPPIST-1 system, lined up in order of increasing distance from their host star. The planetary surfaces are portrayed with an artist’s impression of their potential surface features, including water, ice, and atmospheres. NASA

    ESO Belgian robotic Trappist National Telescope at Cerro La Silla, Chile

    ESO Belgian robotic Trappist-South National Telescope at Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    However, red dwarf stars also present a lot of impediments to habitability, not the least of which is their variable and unstable nature. As O’Malley-James explained to Universe Today via email:

    “The chief barrier to the habitability of these worlds is the activity of their host stars. Regular stellar flares can bathe these planets in high levels of biologically harmful radiation. Furthermore, over longer periods of time, the onslaught of X-ray radiation and charged particle fluxes from the host stars places the atmospheres of these planets at risk of being stripped away over time if a planet cannot replenish its atmosphere fast enough.”

    For generations, scientists have struggled with questions regarding the habitability of planets that orbit red dwarf stars.

    Unlike our Sun, these low-mass, ultra-cool dwarf stars are variable, unstable and prone to flare-ups. These flares release a lot of high-energy UV radiation, which is harmful to life as we know it and capable of stripping a planet’s atmospheres away.

    This places significant limitations on the ability of any planet orbiting a red dwarf star to give rise to life or remain habitable for long. However, as previous studies have shown, much of this depends on the density and composition of the planets’ atmospheres, not to mention whether or not the planet has a magnetic field.

    To determine if life could endure under these conditions, O’Malley-James and Kaltenegger considered what conditions were like on planet Earth roughly 4 billion years ago.

    At that time, Earth’s surface was hostile to life as we know it today. In addition to volcanic activity and a toxic atmosphere, the landscape was bombarded by UV radiation in a way that is similar to what planets that orbit M-type stars experience today.

    To address this, Kaltenegger and O’Malley-James modeled the surface UV environments of four nearby “potentially habitable” exoplanets – Proxima-b, TRAPPIST-1e, Ross-128b and LHS-1140b – with various atmospheric compositions. These ranged from ones similar to present-day Earth to those with “eroded” or “anoxic” atmospheres – i.e. those that don’t block UV radiation well and don’t have a protective ozone layer.

    These models showed that as atmospheres become thinner and ozone levels decrease, more high-energy UV radiation is able to reach the ground. But when they compared the models to what was present on Earth, roughly 4 billion years ago, the results proved interesting. As O’Malley-James said:

    “The unsurprising result was that the levels of surface UV radiation were higher than we experience on Earth today. However, the interesting result was that the UV levels, even for the planets around the most active stars, were all lower than the Earth experienced in its youth. We know the young Earth supported life, so the case for life on planets in M star systems may not be quite so dire after all.”

    What this means, in essence, is that life could exist on neighboring planets like Proxima b right now despite being subjected to harsh levels of radiation. If you consider the age of Proxima Centauri – 4.853 billion years, which is roughly 200 million years older than our Sun – the case for potential habitability may become even more intriguing.

    The current scientific consensus is that the first lifeforms on Earth emerged a billion years after the planet formed (3.5 billion years ago). Assuming Proxima b formed from a protoplanetary debris disk shortly after Proxima Centauri was born, life would have had enough time to not only emerge, but get a significant foothold.

    While that life may consist solely of single-celled organisms, it is encouraging nonetheless. Aside from letting us know that there could very well be life beyond our Solar System, and on nearby planets, it provides scientists with constraints on what type of biosignatures may be discernible when studying them. As O’Malley-James concluded:

    “The results from this study builds the case for focusing on life on Earth a few billion years ago; a world of single-celled microbes – prokaryotes – that lived with high UV radiation levels. This ancient biosphere may have the best overlaps with conditions on habitable planets around active M stars, so could provide us with the best clues in our search for life in these star systems.”

    As always, the search for life in the cosmos begins with the study of Earth, since it is the only example we have of a habitable planet. It is therefore important to understand how (i.e. under what conditions) life was able to survive, thrive and respond to environmental changes throughout Earth’s geological history.

    For while we may know of only one planet that supports life, that life has been remarkably diverse and has changed drastically over time.

    Be sure to check out this video about these latest findings, courtesy of the CSI and Cornell University:

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Carl Sagan Institute (CSI) was founded to find life in the universe. Based on the pioneering work of Carl Sagan at Cornell, our interdisciplinary team is developing the forensic toolkit to find life in the universe, inside the Solar System and outside of it, on planets and moons orbiting other stars.

    Recent scientific results show that in our galaxy alone there are billions of planets orbiting other suns. After billions of years of evolution on our own Pale Blue Dot and thousands of years of questioning, we finally have the technology in hand to explore other worlds inside and outside of our solar system. The information generated by the search for signs of life on other worlds also helps us understand and safeguard our own planet — our Pale Blue Dot — better.

    CSI for the search of life in the universe: CSI explores factors that determine if a planet or moon can host life and how we could find it by bringing together experts from a wide range of disciplines, from sciences, engineering to media who work together with some of the planet’s most talented students at the undergraduate, graduate and postdoctoral level. CSI researchers use the latest data from space telescopes, probes to the solar system’s diverse worlds, field and satellite data on our home planet, laboratory studies of terrestrial organisms, and modeling of complex processes from the astronomical to the biological to explore these profound questions. And CSI researchers participate in the development of the next generation of space- and Earth-based facilities to probe ever deeper and farther.

    CSI also interprets these results for the widest possible audience, sharing the fascination of science with everyone who is interested in where humankind stands in the quest to understand our place in the cosmos.


    The Carl Sagan Institute was founded in 2015 at Cornell University to find life in the universe and explore other worlds – how they form, evolve and if they could harbor life both inside and outside of our own Solar System. Directed by astronomer Lisa Kaltenegger, the Institute has built an entirely new research group, spanning 14 departments at Cornell and including more than 25 faculty who focus on a wide range of the search for life in the universe interdisciplinarily.

    The research group is embedded in a rich environment of established international interdisciplinary cooperation at Cornell. The Institute’s collaboration brings together researchers from fields as far apart as astrophysics, engineering, earth and atmospheric science, geology and biology to tackle questions as diverse as those about the astronomical context of the emergence of life on Earth, how to find it and what this discovery would mean for humankind.

  • richardmitnick 12:24 pm on April 15, 2019 Permalink | Reply
    Tags: "Physicists Have Found an Entirely New Type of Superconductivity", , , Science Alert,   

    From University of Maryland via Science Alert: “Physicists Have Found an Entirely New Type of Superconductivity” 

    U Maryland bloc

    From University of Maryland



    Science Alert

    14 APR 2019

    (Emily Edwards, University of Maryland)

    One of the ultimate goals of modern physics is to unlock the power of superconductivity, where electricity flows with zero resistance at room temperature.

    Progress has been slow, but in 2018, physicists have made an unexpected breakthrough. They discovered a superconductor that works in a way no one’s ever seen before – and it opens the door to a whole world of possibilities not considered until now.

    This 9980-kilogram meteorite, which crashed into Australia, contains tiny amounts of natural superconducting material, physicists have found.

    In other words, they identified a brand new type of superconductivity.

    Why does that matter? Well, when electricity normally flows through a material – for example, the way it travels through wires in the wall when we switch on a light – it’s fast, but surprisingly ineffective.

    Electricity is carried by electrons, which bump into atoms in the material along the way, losing some of their energy each time they have one of these collisions. Known as resistance, it’s the reason why electricity grids lose up to 7 percent of their electricity.

    But when some materials are chilled to ridiculously cold temperatures, something else happens – the electrons pair up, and begin to flow orderly without resistance.

    This is known as superconductivity, and it has incredible potential to revolutionise our world, making our electronics unimaginably more efficient.

    The good news is we’ve found the phenomenon in many materials so far. In fact, superconductivity is already used to create the strong magnetic fields in MRI machines and maglev trains.

    The bad news is that it currently requires expensive and bulky equipment to keep the superconductors cold enough to achieve this phenomenon – so it remains impractical for broader use.

    But in 2018, researchers led by the University of Maryland observed a new type of superconductivity when probing an exotic material at super cool temperatures.

    Not only did this type of superconductivity appear in an unexpected material, the phenomenon actually seemed to rely on electron interactions that are profoundly different from the pairings we’ve seen to date. And that means we have no idea what kind of potential it might have.

    To understand the difference, you need to know that the way electrons interact is dictated by a quantum property called spin.

    In regular superconductors, electrons carry a spin referred to as 1/2.

    But in this particular material, known as YPtBi, the team found that something else was going on – the electrons appear to have a spin of 3/2.

    “No one had really thought that this was possible in solid materials,” explained physicist and senior author Johnpierre Paglione.

    “High-spin states in individual atoms are possible but once you put the atoms together in a solid, these states usually break apart and you end up with spin one-half. ”

    YPtBi was first discovered to be a superconductor a couple of years ago, and that in itself was a surprise, because the material doesn’t actually fit one of the main criteria – being a relatively good conductor, with a lot of mobile electrons, at normal temperatures.

    According to conventional theory, YPtBi would need about a thousand times more mobile electrons in order to become superconducting at temperatures below 0.8 Kelvin.

    But when researchers cooled the material down, they saw superconductivity happening anyway.

    To figure out what was going on, the 2018 study looked at the way the material interacted with magnetic fields to get a sense of exactly what was going on inside.

    Usually as a material undergoes the transition to a superconductor, it will try to expel any added magnetic field from its surface – but a magnetic field can still enter near, before quickly decaying away. How far they penetrate depends on the nature of the electron pairing happening within.

    The team used copper coils to detect changes in YPtBi’s magnetic properties as they changed its temperature.

    What they found was odd – as the material warmed up from absolute zero, the amount that a magnetic field could penetrate the material increased linearly instead of exponentially, which is what is normally seen with superconductors.

    After running a series of measurements and calculations, the researched concluded that the best explanation for what was going on was that the electrons must have been disguised as particles with higher spin – something that wasn’t even considered as a possibility for a superconductor before.

    While this new type of superconductivity still requires incredibly cold temperatures for now, the discovery gives the entire field a whole new direction.

    “We used to be confined to pairing with spin one-half particles,” said lead author Hyunsoo Kim.

    “But if we start considering higher spin, then the landscape of this superconducting research expands and just gets more interesting.”

    This is incredibly early days, and there’s still a lot we have to learn about exactly what’s going on here.

    But the fact that we have a brand new type of superconductivity to test and measure, adding a cool new breakthrough to the 100 years of this type of research, is pretty exciting.

    “When you have this high-spin pairing, what’s the glue that holds these pairs together?” said Paglione.

    “There are some ideas of what might be happening, but fundamental questions remain-which makes it even more fascinating.”

    The research was published in Science Advances.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Maryland Campus

    Driven by the pursuit of excellence, the University of Maryland has enjoyed a remarkable rise in accomplishment and reputation over the past two decades. By any measure, Maryland is now one of the nation’s preeminent public research universities and on a path to become one of the world’s best. To fulfill this promise, we must capitalize on our momentum, fully exploit our competitive advantages, and pursue ambitious goals with great discipline and entrepreneurial spirit. This promise is within reach. This strategic plan is our working agenda.

    The plan is comprehensive, bold, and action oriented. It sets forth a vision of the University as an institution unmatched in its capacity to attract talent, address the most important issues of our time, and produce the leaders of tomorrow. The plan will guide the investment of our human and material resources as we strengthen our undergraduate and graduate programs and expand research, outreach and partnerships, become a truly international center, and enhance our surrounding community.

    Our success will benefit Maryland in the near and long term, strengthen the State’s competitive capacity in a challenging and changing environment and enrich the economic, social and cultural life of the region. We will be a catalyst for progress, the State’s most valuable asset, and an indispensable contributor to the nation’s well-being. Achieving the goals of Transforming Maryland requires broad-based and sustained support from our extended community. We ask our stakeholders to join with us to make the University an institution of world-class quality with world-wide reach and unparalleled impact as it serves the people and the state of Maryland.

  • richardmitnick 3:29 pm on April 12, 2019 Permalink | Reply
    Tags: , , Laser technology to understand the quantum nature of a vacuum setting a landmark in our attempts to measure absolute nothingness, Science Alert   

    From ETH Zürich via Science Alert: “For The First Time, Physicists Have Managed to Measure Precisely Absolutely Nothing” 

    ETH Zurich bloc

    From ETH Zürich



    Science Alert

    12 APR 2019


    For some physicists, measuring the spectrum of tiny waves making up empty space has been a goal for decades, but until now none have found a good way to achieve it.

    Now physicists from ETH Zürich have cleverly used laser pulses to understand the quantum nature of a vacuum, setting a landmark in our attempts to measure absolute nothingness.

    Our Universe is fundamentally bumpy. Like a fresh canvas yet to be painted, there’s a texture to bare reality which we can only just detect.

    What we take for the complete absence of matter and radiation is an infinite field of possibility from which particles emerge. In fact, there is a field for every elemental particle, just waiting for sufficient energy to define key features of its existence.

    Those particles are all constrained by a strange rule – as some possibilities increase, others have to shrink. A particle can be in a precise location, for example, but it will have a vague momentum. Or vice versa.

    This uncertainty principle doesn’t just apply to particles. It applies to the vacant field itself.

    Standing back, that artist’s canvas looks remarkably smooth. Likewise, over an extended period of time, the amount of energy in a volume of empty space averages out to zero.

    But as we focus in, for any single moment we become less certain about how much energy we’ll find, resulting in a spectrum of probabilities.

    We typically think of this weave as random. But there are correlations which could tell us a thing or two about the nature of this rippling.

    “The vacuum fluctuations of the electromagnetic field have clearly visible consequences, and among other things, are responsible for the fact that an atom can spontaneously emit light,” says physicst Ileana-Cristina Benea-Chelmus from the Institute for Quantum Electronics at ETH Zurich.

    To measure most things, you need to establish a starting point. Unfortunately for something already in its lowest energy state, it’s a little like measuring the force of a punch from a non-moving fist.

    “Traditional detectors for light such as photodiodes are based on the principle that light particles – and hence energy – are absorbed by the detector,” says says Benea-Chelmus.

    “However, from the vacuum, which represents the lowest energy state of a physical system, no further energy can be extracted.”

    Rather than measure the transfer of energy from an empty field, the team devised a way to look for the signature of its subtle probability shifts in the polarisation of photons.

    By comparing two laser pulses just a trillionth of a second in length, sent through a super-cold crystal at different times and locations, the team could work out how the empty space between the crystal’s atoms affected the light.

    “Still, the measured signal is absolutely tiny, and we really had to max out our experimental capabilities of measuring very small fields,” says physicist Jérôme Faist.

    Tiny is an understatement. That quantum ‘wiggle’ was so small, they needed up to a trillion observations for each comparison just to be sure the measurements were legitimate.

    As miniscule as the final results happened to be, the measurements allowed them to determine the fine spectrum of an electromagnetic field in its ground state.

    Getting a grip on what is effectively empty space is becoming a big deal in quantum physics.

    Only recently, another team of physicists attempted to put limits on the noise of a vacuum at room temperature in order to improve the functionality of the gravitational wave detector LIGO.

    Virtual particles – the brief ghosts of possible particles that barely exist as uncertainties in a field – are also key to understanding how black holes slowly evaporate away over time through Hawking radiation.

    In the future, we’ll need even more tricks like these if we’re to understand the fabric the Universe is painted on.

    This research was published in Nature.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    ETH Zurich campus
    ETH Zürich is one of the leading international universities for technology and the natural sciences. It is well known for its excellent education, ground-breaking fundamental research and for implementing its results directly into practice.

    Founded in 1855, ETH Zürich today has more than 18,500 students from over 110 countries, including 4,000 doctoral students. To researchers, it offers an inspiring working environment, to students, a comprehensive education.

    Twenty-one Nobel Laureates have studied, taught or conducted research at ETH Zürich, underlining the excellent reputation of the university.

  • richardmitnick 9:14 am on April 11, 2019 Permalink | Reply
    Tags: "New Quantum Computer Can Hold a Superposition of Many Possible Futures Simultaneously", , , Nanyang Technological University, Science Alert   

    From Griffith University via Science Alert: “New Quantum Computer Can Hold a Superposition of Many Possible Futures Simultaneously” 

    Griffith U bloc

    From Griffith University



    Science Alert

    10 APR 2019


    Unlike classical particles, quantum particles can travel in a quantum superposition of different directions. Mile Gu, together with researchers from Griffith harnessed this phenomena to design quantum devices that can generate a quantum superposition of all possible futures. Credit: NTU, Singapore.

    A team of scientists says they’ve built a quantum computer that generates a superposition of several possible futures the computer could experience.

    The research, published Tuesday in Nature Communications, describes how this quantum system could help futuristic artificial intelligence learn much faster than it can today – and it could mean quantum computers are finally becoming practical tools.

    For now, the quantum computer built by Griffith University and Nanyang Technological University scientists can hold two superpositions of 16 different possibilities, according to the research.

    A picture of the Experimental Device used for the experiment. Credit: Griffith’s University

    It also uses less memory than a classical computer would, suggesting it could outperform classical systems at certain tasks.

    “This is what makes the field so exciting. It is very much reminiscent of classical computers in the 1960s,” Griffith University scientist Geoff Pryde said in a press release.

    “Just as few could imagine the many uses of classical computers in the 1960s, we are still very much in the dark about what quantum computers can do.”

    Right now, artificial intelligence learns by analyzing example after example and looking for patterns. The scientists behind this research argue that their quantum superpositions could vastly improve the process.

    “By interfering these superpositions with each other, we can completely avoid looking at each possible future individually,” Griffith researcher Farzad Ghafari said in the press release.


    “In fact, many current artificial intelligence algorithms learn by seeing how small changes in their behaviour can lead to different future outcomes, so our techniques may enable quantum enhanced AIs to learn the effect of their actions much more efficiently.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Griffith U Campus

    In 1971, Griffith was created to be a new kind of university—one that offered new degrees in progressive fields such as Asian studies and environmental science. At the time, these study areas were revolutionary—today, they’re more important than ever.

    Since then, we’ve grown into a comprehensive, research-intensive university, ranking in the top 5% of universities worldwide. Our teaching and research spans five campuses in South East Queensland and all disciplines, while our network of more than 120,000 graduates extends around the world.

    Griffith continues the progressive traditions of its namesake, Sir Samuel Walker Griffith, who was twice the Premier of Queensland, the first Chief Justice of the High Court of Australia, and the principal author of the Australian Constitution.

  • richardmitnick 11:11 am on March 11, 2019 Permalink | Reply
    Tags: "The US Is Only Decades Away From Widespread Water Shortages, , , Much of the United States could be gripped by significant water shortages in just five decades' time according to predictions made in a new study., Science Alert, Scientists Warn"   

    From Science Alert: “The US Is Only Decades Away From Widespread Water Shortages, Scientists Warn” 


    From Science Alert

    11 MAR 2019

    Glen Canyon Dam, Arizona. (John Gibbons/Unsplash)

    Much of the United States could be gripped by significant water shortages in just five decades’ time, according to predictions made in a new study.

    From the year 2071 on, scientists say the combined effects of climate change and population increases are projected to present “serious challenges” [Earth’s Future] in close to half of the 204 watersheds covering the contiguous US.

    In the researchers’ projections, water supply is likely to be under threat in watersheds in the central and southern Great Plains, the Southwest and central Rocky Mountain States, California, and areas in the South (especially Florida) and the Midwest.

    “There’s a lot of the US over time that will have less water,” one of the researchers, economist Thomas Brown from the US Forest Service told Reuters.

    To reach their estimates, Brown and his team used a number of global climate models to project future climate scenarios, while factoring in data on expected population growth.

    According to the scientists, water stability in the US was achieved in the 1980s, after decades of increased demand which saw water usage surge ninefold since the turn of the 20th century.

    Thanks to advances in dams, tunnelling, and pipelines, stability in water usage has been maintained since then despite a growing population, the team says, but with reservoir construction peaking in the 1960s, those adaptations won’t keep delivering the same way in the future.

    “Although studies show that climate change is likely to bring increasing precipitation in many areas of the contiguous 48 states of the [US], especially in northern regions, other areas are expected to receive less,” the authors write [Earth’s Future] above.

    “Furthermore, increasing temperatures, which are expected everywhere in the US, will tend to lower streamflow via the effect of temperature on evaporative demand, in some areas completely negating the positive effect of increasing precipitation and leading to decreasing streamflow.”

    In the study, the researchers modelled water supply and demand for 14 alternative climatic futures, using two future greenhouse gas emission scenarios with seven global climate models, and assuming water use efficiency will continue to improve as it has in the past.

    While the findings are only projections and inherently uncertain, as the researchers acknowledge, they are nonetheless grim.

    “In future periods, as population and economic growth plus the changing climate alter water yield and demand, shortages are projected to increase substantially, in the absence of adaptation measures, with many of the 14 futures we examined,” the researchers explain [Earth’s Future] above.

    “Averaging across the 14 futures, 83, 92, and 96 basins are projected to incur some level of monthly shortage in the near [2021–2045], middle [2046–2070], and far future periods [2071–2095].”

    The team is eager to emphasise that these projected water shortages are not locked in, though, and could be mitigated by ongoing and future adaptations to water usage – especially in agriculture (which accounts for 75 percent of annual water consumption in the US) and industry.

    In previous decades, reservoir construction has been a massive boon to water stability, but as the world gets hotter and drier, the researchers say it will be less useful compared to other 21st century adaptations, such as boosting irrigation efficiency.

    “Where water is the limiting factor, a reservoir enlargement is unlikely to store any water,” Brown says.

    Tapping into groundwater is another option, but given that it is a limited and threatened resource itself, it’s not something we should be too reliant on, the researchers say.

    Instead, our water usage as a whole has to be looked at, and we particularly need to look at increasing the efficiency of usage among the primary users of this limited and precious resource.

    “In reality, irrigated agriculture is unlikely to bear the full burden of accommodating future water shortages,” the authors write.

    “Nevertheless, given the large quantities of water used in agriculture and the fact that most of that water is used to grow relatively low‐value crops, the agriculture sector is likely to face serious challenges, all else equal.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 9:26 am on March 9, 2019 Permalink | Reply
    Tags: "This Lab Has Built a Prototype 'Anti-Laser' That Swallows Light", As a first attempt it's very promising., Being treated with an anti-laser sounds pretty cool to us., Blueprint for building an anti-laser that's more complex than anything we've seen before, Both the frequency of the signal and the absorption strength have to be carefully calibrated., It's that versatility and flexibility that sets this new anti-laser apart from previous such devices, Key to the process is finding a wave front for the incoming signals in order to perfectly absorb them., More than an anti-laser this team's device is a 'random anti-laser': capable of absorbing waves randomly scattered in all directions, Science Alert, So far anti-lasers have only been realised in one-dimensional structures onto which laser light was directed from opposite sides., , That high mark is only in tightly controlled conditions though., That then enables the absorption of waves that aren't arriving in predictable ways., The researchers managed to get an absorption rate of approximately 99.8 percent of the signals they broadcast., This ability could have a variety of potential uses in everything from phone antennas to medical equipment – anywhere waves are captured., We were able to show that even arbitrarily complicated structures in two or three dimensions can perfectly absorb a suitably tailored wave., You can think of such a device as a laser light burst happening in reverse - getting swallowed up rather than beamed out   

    From Techniche Universitat Wein (Vienna) via Science Alert: “This Lab Has Built a Prototype ‘Anti-Laser’ That Swallows Light” 

    Techniche Universitat Wein (Vienna)

    From Techniche Universitat Wein (Vienna)



    Science Alert

    8 MAR 2019


    In recent years scientists have started exploring the concept of anti-lasers – devices that can perfectly absorb a particular wavelength of light, as opposed to emitting it the way a laser does.

    Now researchers have published a study that explores the blueprint for building an anti-laser that’s more complex than anything we’ve seen before.

    More than an anti-laser, this team’s device is a ‘random anti-laser’: capable of absorbing waves randomly scattered in all directions. This ability could have a variety of potential uses, in everything from phone antennas to medical equipment – anywhere waves are captured.

    An anti-laser may sound wild, but it’s actually pretty much what it says on the tin. You can think of such a device as a laser light burst happening in reverse – getting swallowed up rather than beamed out, according to the researchers.

    “So far, anti-lasers have only been realised in one-dimensional structures onto which laser light was directed from opposite sides,” says one of the team, Stefan Rotter from the Vienna University of Technology in Austria.

    “Our approach is much more general: we were able to show that even arbitrarily complicated structures in two or three dimensions can perfectly absorb a suitably tailored wave. In this way, this novel concept can also be used for a much wider range of applications.”

    It’s that versatility and flexibility that sets this new anti-laser apart from what previous such devices. The team worked up a set of calculations and computer simulations to theorise how such a perfectly absorbing anti-laser might work, then backed them up with physical lab tests.

    Key to the process is finding a wave front for the incoming signals in order to perfectly absorb them. That then enables the absorption of waves that aren’t arriving in predictable ways, but rather as scattered signals bouncing in from multiple sources.

    “Waves that are being scattered in a complex way are really all around us – think about a mobile phone signal that is reflected several times before it reaches your cell phone,” says Rotter.

    “This multiple scattering is made practical use of in so-called random lasers. Such exotic lasers are based on a disordered medium with a random internal structure that can trap light and emit a very complicated, system-specific laser field when supplied with energy.”

    The random anti-laser setup. (Vienna University of Technology)

    When it came to building their own anti-laser, the scientists set up a series of randomly placed Teflon cylinders, and sent microwave signals scattering through them – a little bit like rocks deflecting water waves in a puddle of water.

    A waveguide placed on top with an antenna in its centre was used to absorb the incoming waves. The researchers managed to get an absorption rate of approximately 99.8 percent of the signals they broadcast.

    That high mark is only in tightly controlled conditions, though – the team first measured the wave reflections as they came back in order to finely tune the central antenna to absorb them. Both the frequency of the signal and the absorption strength have to be carefully calibrated.

    As a first attempt though, it’s very promising, and the theoretical physics behind the project suggests it can be adapted to a range of other signals and applications. It could work for any scenario “in which waves need to be perfectly focused, routed or absorbed”, write the researchers.

    “Imagine, for example, that you could adjust a cell phone signal exactly the right way, so that it is perfectly absorbed by the antenna in your cell phone,” says Rotter.

    “Also in medicine, we often deal with the task of delivering wave energy to a very specific point – such as shock waves shattering a kidney stone.”

    Being treated with an anti-laser sounds pretty cool to us.

    The research has been published in Nature.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Techniche Universitat Wein (Vienna) campus

    Our mission is “technology for people”. Through our research we “develop scientific excellence”,
    through our teaching we “enhance comprehensive competence”.

    TU Wien (TUW) is located in the heart of Europe, in a cosmopolitan city of great cultural diversity. For nearly 200 years, TU Wien has been a place of research, teaching and learning in the service of progress. TU Wien is among the most successful technical universities in Europe and is Austria’s largest scientific-technical research and educational institution.

  • richardmitnick 10:52 am on March 7, 2019 Permalink | Reply
    Tags: "The hypothetical effect we are investigating is not the result of increased gravity" Budker said., "What if It's Not Dark Matter Making The Universe's Extra 'Gravity' But Light?", As we move out from the galactic centre the orbital motion of the stars and gas in the disc should theoretically slow down with the decrease in velocity proportional to the distance from the centre., , , , But that something might not be dark matter according to a team of researchers specifically plasma physicist Dmitri Ryutov retired from the Lawrence Livermore National Laboratory in California, But unless all our current understanding about the physical Universe (and all the data we've collected on the phenomenon is wrong) something out there is definitely making extra gravity., , , For now dark matter is still king. But there's no harm and potentially a lot of good in looking for other explanations too., Science Alert, So astrophysicists hypothesised dark matter. We don't know what it is and we can't detect it directly., So the theory would need a bit of work to be compatible with our actual observations of the Universe., , What if it's the mass of light?, When placed in the context of a mathematical system called Maxwell-Proca electrodynamics these electromagnetic stresses can generate additional centripetal forces   

    From Science Alert: “What if It’s Not Dark Matter Making The Universe’s Extra ‘Gravity’, But Light?” 


    From Science Alert

    7 MAR 2019

    (NASA/ESA/ Hubble)

    NASA/ESA Hubble Telescope

    We’ve been looking for decades for dark matter, yet the mysterious stuff remains undetectable to our instruments. Now, astrophysicists have explored an intriguing possibility: what if it’s not dark matter that’s affecting galactic rotation after all. What if it’s the mass of light instead?

    In a 1980 paper [The Astrophysical Journal], the American astronomer Vera Rubin pretty conclusively proved something really weird about galaxies: their rims are rotating far faster than they should be.

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster. But Vera Rubin, Vera Rubin a Woman in STEM denied the Nobel, did most of the work on Dark Matter.

    Fritz Zwicky from http:// palomarskies.blogspot.com

    Coma cluster via NASA/ESA Hubble

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science)

    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL)

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    As we move out from the galactic centre, the orbital motion of the stars and gas in the disc should theoretically slow down, with the decrease in velocity proportional to the distance from the centre.

    This is called Keplerian decline, or decreasing rotation curve, and it can be observed quite neatly in planetary systems like our own Solar System. But most galaxies don’t actually do this.

    Instead, their rotation curves either remain flat, or actually increase. Those outer stars are orbiting much more quickly than they should be, based on the gravitational effect of the matter we can observe.

    So astrophysicists hypothesised dark matter. We don’t know what it is, and we can’t detect it directly. But unless all our current understanding about the physical Universe (and all the data we’ve collected on the phenomenon is wrong), something out there is definitely making extra gravity.

    But that something might not be dark matter, according to a team of researchers – specifically, plasma physicist Dmitri Ryutov, who recently retired from the Lawrence Livermore National Laboratory in California, and Dmitry Budker and Victor Flambaum of the Johannes Gutenberg University of Mainz in Germany.

    In a new paper [The Astrophysical Journal], they lay out an argument that light particles (photons) are at least partially the source of the phenomenon – causing an effect that isn’t gravity, but behaves a heck of a lot like it.

    “The hypothetical effect we are investigating is not the result of increased gravity,” Budker said.

    “By assuming a certain photon mass, much smaller than the current upper limit, we can show that this mass would be sufficient to generate additional forces in a galaxy and that these forces would be roughly large enough to explain the rotation curves. This conclusion is extremely exciting.”

    The effect they describe is a sort of “negative pressure” caused by electromagnetic stresses related to the photon mass.

    When placed in the context of a mathematical system called Maxwell-Proca electrodynamics, these electromagnetic stresses can generate additional centripetal forces, acting predominantly on interstellar gas. The team calls this Proca stress, and it acts a lot like gravity.

    So, yes, it’s all purely hypothetical at this point. And it’s not perfect.

    On the one hand, short-lived stars that are born from gas (and rapidly return to gas before completing one orbit) would be strongly coupled with the gas; the Proca stresses acting on the gas would be indirectly also acting on these stars.

    But longer-lived stars create a problem. The Sun, for example, is around 4.6 billion years old, and orbits the galactic centre once every 230 million years, so it’s had a few turns on the roundabout. According to the team’s calculations, it should have a highly elliptical orbit under Proca stresses.

    And yet it does not. So the theory would need a bit of work to be compatible with our actual observations of the Universe. For now, dark matter is still king. But there’s no harm, and potentially a lot of good, in looking for other explanations too.

    “We don’t currently consider photon mass to be the solution to the rotation-curve problem. But it could be part of the solution,” Budker said.

    “However, we need to keep an open mind as long as we do not actually know what dark matter is.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

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