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  • richardmitnick 2:10 pm on August 4, 2016 Permalink | Reply
    Tags: , , DEIXIS, , Quark-gluon plasma   

    From BNL via DEIXIS: “Early-universe soup” 

    Brookhaven Lab

    1

    DEIXIS

    June 22nd, 2016 [Just now in social media]
    Sarah Webb

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    An experimental and theoretical exploration of the quantum chromodynamics (QCD) phase diagram. The matter produced in collisions at the highest energies and the smallest baryon chemical potentials can change from quark-gluon plasma (QGP) to a hadron gas through a smooth crossover. But lower energy collisions can access higher baryon chemical potentials where a first-order phase transition line is thought to exist. The reach of the future DOE Basic Energy Sciences program at RHIC is shown, as are the trajectories on the phase diagram followed by the cooling droplets of QGP produced in collisions with varying energy. The present reach of lattice QCD calculations is illustrated by the yellow band. (Illustration: Swagato Mukherjee, Brookhaven National Laboratory.)

    ORNL’s Titan supercomputer is helping Brookhaven physicists understand the matter that formed microseconds after the Big Bang.

    ORNL Cray Titan Supercomputer
    ORNL Cray Titan Supercomputer

    At the dawn of the universe – just after the Big Bang – all matter was in the form of a hot-flowing soup called quark-gluon plasma, or QGP. Though a few ambitious, atom-smashing experiments have produced transient samples of this extreme phase of matter, researchers still have much to learn about its fundamental behavior.

    Experimental physicists have tried to produce quark-gluon plasma since the 1980s and first reported observing it in 2000. Over the past 45 years, theorists have outlined the equations that govern QGP and many have combined theory and experiment to describe it.

    Large-scale computations have been critical to the theoretical study of QGP’s novel characteristics. As part of a theoretical effort funded by the Department of Energy, Brookhaven National Laboratory’s Swagato Mukherjee and his colleagues are using an allotment of 167 million processor hours from the ASCR Leadership Computing Challenge (ALCC) to better understand QGP. Their findings will help physicists plan the next wave of experiments. “Neither theory nor experiment can do this alone,” Mukherjee says.

    At the heart of every atom lies the nucleus, a super-tight ball of subatomic protons and neutrons. Those particles are made of even smaller parts, including quarks, which comprise just one thousandth of the mass. Gluons, the adhesive particles that hold quarks together, carry the strong interaction, a fundamental physical force that binds the atomic nucleus and generates the other 99.9 percent of all matter’s mass.

    But at temperature extremes 70,000 times hotter than the center of the sun, even tightly packed quarks and gluons begin to flow. The transition to the flowing state is much like phase changes in matter such as water. Water exists as liquid, steam or ice, based on how much heat and pressure are applied. Scientists long ago carefully mapped the underlying conditions and boundaries between water’s different forms as a phase diagram, information that’s been critical for understanding water’s behavior. If researchers can understand how changes in temperature and density affect QGP, physicists can create a similar roadmap documenting conditions that form it.

    Because of the extreme conditions required for QGP creation, the only way to observe it on Earth is to bombard matter with high-energy particles at either the Relativistic Heavy Ion Collider (RHIC) at Brookhaven or the Large Hadron Collider at CERN in Switzerland.

    BNL/RHIC
    BNL/RHIC

    CERN LHC Grand Tunnel
    LHC
    Fast-moving nuclei of lead and gold collide at high energy, briefly producing the plasma-soup researchers can study.

    Experiments aren’t the only way to study QGP’s properties. Physicists have worked out the theory of how quarks and gluons interact, known as quantum chromodynamics, or QCD. However, the complexity of these interactions, with billions of variables, requires sophisticated parallel computing resources to solve, Mukherjee says.

    Using their ALCC allotment, Mukherjee and his colleagues have concentrated on a version of this theory, lattice QCD, to computationally study the plasma on Titan, a Cray XK7 at Oak Ridge National Laboratory. The calculations line up quarks at the intersection points on a grid, with gluons positioned on each of the crossbars between them. Initially, the researchers omitted the density component and solely calculated how increasing heat eventually produces the flowing QGP. Now they’ll need to consider the density component as well. With their ongoing ALCC allotment, they’re simulating how increasing density changes the phase diagram and eventually the plasma’s behavior.

    These types of computations will be critical for future experiments at the big colliders. In 2019 and 2020, DOE will support a large collaborative effort, the Beam Energy Scan II at RHIC, to observe the full phase diagram of quark-gluon plasma, including the density component, Mukherjee says, an effort that will cost hundreds of millions of dollars. The calculations Mukherjee and his colleagues perform will provide information that helps the experimental physicists plan those experiments. The calculations will provide temperature benchmarks – a range needed to generate QGP.

    In large particle accelerators, researchers can’t control the temperature or density, only the energy of the atomic collisions, Mukherjee says. So calculations will help researchers translate that collision energy into the heat and density parameters they need to observe the full range of changes in the phase diagram of quark-gluon plasma.

    Ultimately, the exercise is about fundamental discovery and collaboration between theorists and experimentalists to discover the quark-gluon soup recipe. Mukherjee is part of a larger Brookhaven theoretical team, the Nuclear Physics Lattice Gauge Theory group led by Fritjof Karsch. This work is an integral part of the BEST collaboration – for Beam Energy Scan Theory – a DOE-funded, multi-institutional Topical Collaboration in Nuclear Theory, looking at the phases and properties of hot-dense QCD matter. Mukherjee’s research is supported by DOE Office of Science’s Nuclear Physics program.

    See the full article here .

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    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 3:21 pm on April 10, 2016 Permalink | Reply
    Tags: , , , , , , Quark-gluon plasma   

    From The Daily Galaxy: “CERN LHC Reveals: “The Universe a Billionth of a Second After the Big Bang” 

    Daily Galaxy
    The Daily Galaxy

    CERN/LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    April 09, 2016
    No writer credit found

    “It is remarkable that we are able to carry out such detailed measurements on a drop of ‘early universe’, that only has a radius of about one millionth of a billionth of a meter. The results are fully consistent with the physical laws of hydrodynamics, i.e. the theory of flowing liquids and it shows that the quark-gluon plasma behaves like a fluid.

    It is however a very special liquid, as it does not consist of molecules like water, but of the fundamental particles quarks and gluons,” explained Jens Jørgen Gaardhøje, professor and head of the ALICE group at the Niels Bohr Institute at the University of Copenhagen.

    A few billionths of a second after the Big Bang, the universe was made up of a kind of extremely hot and dense primordial soup of the most fundamental particles, especially quarks and gluons. This state is called quark-gluon plasma. By colliding lead nuclei at a record-high energy of 5.02 TeV in the world’s most powerful particle accelerator, the 27 km long Large Hadron Collider, LHC at CERN in Geneva, it has been possible to recreate this state in the ALICE experiment’s detector and measure its properties.

    Quark gluon plasma. Duke University
    Quark-gluon plasma. Duke University

    CERN researchers recreated the universe’s primordial soup in miniature format by colliding lead atoms with extremely high energy in the 27 km long particle accelerator, the LHC in Geneva. The primordial soup is a so-called quark-gluon plasma and researchers from the Niels Bohr Institute, among others, have measured its liquid properties with great accuracy at the LHC’s top energy. The results were submitted to Physical Review Letters, which is the top scientific journal for nuclear and particle physics.

    “The analyses of the collisions make it possible, for the first time, to measure the precise characteristics of a quark-gluon plasma at the highest energy ever and to determine how it flows,” explains You Zhou, who is a postdoc in the ALICE research group at the Niels Bohr Institute.

    CERN ALICE Icon HUGE
    ALICE Run Control Center
    CERN ALICE New
    CERN ALICE New II
    CERN ALICE and the Control Room

    You Zhou, together with a small, fast-working team of international collaboration partners, led the analysis of the new data and measured how the quark-gluon plasma flows and fluctuates after it is formed by the collisions between lead ions.

    The focus has been on the quark-gluon plasma’s collective properties, which show that this state of matter behaves more like a liquid than a gas, even at the very highest energy densities. The new measurements, which uses new methods to study the correlation between many particles, make it possible to determine the viscosity of this exotic fluid with great precision.

    You Zhou explains that the experimental method is very advanced and is based on the fact that when two spherical atomic nuclei are shot at each other and hit each other a bit off center, a quark-gluon plasma is formed with a slightly elongated shape somewhat like an American football. This means that the pressure difference between the centre of this extremely hot ‘droplet’ and the surface varies along the different axes. The pressure differential drives the expansion and flow and consequently one can measure a characteristic variation in the number of particles produced in the collisions as a function of the angle.

    Jens Jørgen Gaardhøje adds that they are now in the process of mapping this state with ever increasing precision — and even further back in time.

    See the full article here .

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  • richardmitnick 8:34 am on February 26, 2016 Permalink | Reply
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    From phys.org: “The universe’s primordial soup flowing at CERN” 

    physdotorg
    phys.org

    February 9, 2016

    Researchers have recreated the universe’s primordial soup in miniature format by colliding lead atoms with extremely high energy in the 27 km long particle accelerator, the LHC at CERN in Geneva.

    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    The primordial soup is a so-called quark-gluon plasma and researchers from the Niels Bohr Institute, among others, have measured its liquid properties with great accuracy at the LHC’s top energy. The results have been submitted to Physical Review Letters.

    Quark gluon plasma

    A few billionths of a second after the Big Bang, the universe was made up of a kind of extremely hot and dense primordial soup of the most fundamental particles, especially quarks and gluons. This state is called quark-gluon plasma. By colliding lead nuclei at a record-high energy of 5.02 TeV in the world’s most powerful particle accelerator, the 27 km long Large Hadron Collider, LHC at CERN in Geneva, it has been possible to recreate this state in the ALICE experiment’s detector and measure its properties.

    “The analyses of the collisions make it possible, for the first time, to measure the precise characteristics of a quark-gluon plasma at the highest energy ever and to determine how it flows,” explains You Zhou, who is a postdoc in the ALICE research group at the Niels Bohr Institute. You Zhou, together with a small, fast-working team of international collaboration partners, led the analysis of the new data and measured how the quark-gluon plasma flows and fluctuates after it is formed by the collisions between lead ions.

    Advanced methods of measurement

    The focus has been on the quark-gluon plasma’s collective properties, which show that this state of matter behaves more like a liquid than a gas, even at the very highest energy densities. The new measurements, which uses new methods to study the correlation between many particles, make it possible to determine the viscosity of this exotic fluid with great precision.

    You Zhou explains that the experimental method is very advanced and is based on the fact that when two spherical atomic nuclei are shot at each other and hit each other a bit off center, a quark-gluon plasma is formed with a slightly elongated shape somewhat like an American football. This means that the pressure difference between the centre of this extremely hot ‘droplet’ and the surface varies along the different axes. The pressure differential drives the expansion and flow and consequently one can measure a characteristic variation in the number of particles produced in the collisions as a function of the angle.

    Mapping the primordial soup

    “It is remarkable that we are able to carry out such detailed measurements on a drop of ‘early universe’, that only has a radius of about one millionth of a billionth of a meter. The results are fully consistent with the physical laws of hydrodynamics, i.e. the theory of flowing liquids and it shows that the quark-gluon plasma behaves like a fluid. It is however a very special liquid, as it does not consist of molecules like water, but of the fundamental particles quarks and gluons,” explains Jens Jørgen Gaardhøje, professor and head of the ALICE group at the Niels Bohr Institute at the University of Copenhagen.

    Jens Jørgen Gaardhøje adds that they are now in the process of mapping this state with ever increasing precision—and even further back in time.

    See the full article here .

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 4:43 pm on September 10, 2015 Permalink | Reply
    Tags: , , , , Quark-gluon plasma   

    From BNL: “Tiny Drops of Early Universe ‘Perfect’ Fluid” 

    Brookhaven Lab

    August 31, 2015
    Karen McNulty Walsh, (631) 344-8350 or Peter Genzer, (631) 344-3174

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    The upper panel of this image, created based on calculations by Brookhaven Lab nuclear theorist Bjoern Schenke, represents initial hot spots created by collisions of one, two, and three-particle ions with heavy nuclei. The lower panel shows the geometrical patterns of particle flow that would be expected if the small-particle collisions are creating tiny hot spots of quark-gluon plasma. No image credit.

    The Relativistic Heavy Ion Collider (RHIC), a particle collider for nuclear physics research at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, smashes large nuclei together at close to the speed of light to recreate the primordial soup of fundamental particles that existed in the very early universe.

    BNL RHIC Campus
    BNL RHIC

    Experiments at RHIC—a DOE Office of Science User Facility that attracts more than 1,000 collaborators from around the world—have shown that this primordial soup, known as quark-gluon plasma (QGP), flows like a nearly friction free “perfect” liquid. New RHIC data just accepted for publication in the journal Physical Review Letters now confirm earlier suspicions that collisions of much smaller particles can also create droplets of this free-flowing primordial soup, albeit on a much smaller scale, when they collide with the large nuclei.

    “These tiny droplets of quark-gluon plasma were at first an intriguing surprise,” said Berndt Mueller, Associate Laboratory Director for Nuclear and Particle Physics at Brookhaven. “Physicists initially thought that only the nuclei of large atoms such as gold would have enough matter and energy to set free the quark and gluon building blocks that make up protons and neutrons. But the flow patterns detected by RHIC’s PHENIX collaboration in collisions of helium-3 nuclei with gold ions now confirm that these smaller particles are creating tiny samples of perfect liquid QGP.”

    These results build on earlier findings from collisions of two-particle ions known as deuterons with gold ions at RHIC, as well as proton-lead and proton-proton collisions at Europe’s Large Hadron Collider (LHC).

    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    They also set the stage for the current run colliding protons with gold at RHIC.

    “The idea that collisions of small particles with larger nuclei might create minute droplets of primordial quark-gluon plasma has guided a series of experiments to test this idea and alternative explanations, and stimulated a rich debate about the implications of these findings,” said University of Colorado physicist Jamie Nagle, a co-spokesperson of the PHENIX collaboration at RHIC. “These experiments are revealing the key elements required for creating quark-gluon plasma and could also offer insight into the initial state characteristics of the colliding particles.”

    Geometrical flow patterns

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    RHIC’s PHENIX detector

    The discovery of the “perfect” liquid at RHIC, announced definitively in 2005, was largely based on observations of particles flowing in an elliptical pattern from the matter created in RHIC’s most energetic gold-gold collisions. This flow was a clear sign that particles emerging from the collisions were behaving in a correlated, or collective, way that contrasted dramatically with the uniformly expanding gas the scientists had expected. Additional experiments confirmed that this liquid is indeed composed of visible matter’s most fundamental building blocks, quarks and gluons, no longer confined within individual protons and neutrons, and that the flow occurs with minimal resistance—making it a nearly “perfect” liquid QGP.

    “Experiments colliding smaller particles with the heavy ions were originally designed as control experiments because they weren’t supposed to create the QGP,” Nagle said. “But observations at the LHC of very energetic proton-proton collisions and later experiments there colliding protons with lead revealed hints that particles streaming from those tiny collisions were also behaving collectively and flowing. It looked a lot like some of the perfect liquid signatures originally discovered in gold-gold collisions at RHIC, and later in lead-lead collisions at the LHC.”

    When RHIC physicists checked data from the RHIC run of 2008, when deuterons (a nucleus made of one proton and one neutron) were smashed into gold ions, they saw a similar pattern.

    “Since the deuteron is two particles, it creates two separate impacts on the nucleus—two hot spots that appear to merge and form an elongated drop of QGP,” Nagle said.

    Definitive tests

    Those observations triggered the idea of testing for flow patterns in a range of more tightly controlled experiments, which is only possible at RHIC, where physicists can collide a wide variety of ions to control the shape of the droplets of matter created. With additional deuteron-gold collisions already in hand, the RHIC scientists set out to collide three-particle helium-3 nuclei (each made of two protons and one neutron) with gold—and later, single protons with gold.

    “The PHENIX detector can pick up particles coming out of collisions very far forward and backward from the collision point. This large angle coverage allows us to measure the flow in these small collision systems,” said Shengli Huang, a PHENIX collaborator from Vanderbilt University who carried out the analysis. “PHENIX also has a trigger detector that picks up and records the most violent collisions—the ones in which the flow pattern is most apparent,” he said.

    The analysis of those events, as described in the new paper, reveals that the helium-gold collisions exhibit a triangular pattern of flow that the scientists say is consistent with the creation of three tiny droplets of QGP. They also say the data indicate that these small particle collisions could be producing the extreme temperatures required to free quarks and gluons—albeit at a much smaller, more localized scale than in the relatively big domains of QGP created in collisions of two heavy ions.

    “This is a pretty definitive measurement,” Nagle said. “The paper has a plot of elliptical and triangular flow that pretty much matches the hydrodynamic flow calculations we’d expect for QGP. We are really engineering different shapes of the QGP to manipulate it and see how it behaves.”

    There are other key signatures of QGP formation, such as the stopping of energetic particle jets, which have not been detected in the tiny droplets. And other theoretical explanations suggest the flow patterns resulting from some of the small particle-nucleus collisions could emerge from the interactions of gluons within the colliding particles, rather than from the formation of QGP.

    “At this time, the only theoretical framework that reproduces the patterns we’re observing in deuteron-gold and helium-3-gold collisions is fluid dynamics,” said Bjoern Schenke, a nuclear theorist at Brookhaven Lab. “It remains to be seen if alternative models can describe these patterns as well.”

    If other models also turn out to be compatible with the helium-3-gold data, physicists will want to explore whether these models make predictions that differ from those of the hydrodynamic flow model, and for which types of collisions.

    “The good news is that RHIC, with its unrivaled versatility, will likely be able to study any system that can discriminate between different models,” Mueller said.

    Research at RHIC is funded primarily by the DOE Office of Science.

    See the full article here .

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    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 10:26 am on July 23, 2015 Permalink | Reply
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    From Rice: “Rice physicists find surprising ‘liquid-like’ particle interactions in Large Hadron Collider” 

    Rice U bloc

    Rice University

    July 22, 2015

    2
    Don Lincoln

    Three years ago, Rice physicists and their colleagues on the Large Hadron Collider’s (LHC’s) Compact Muon Solenoid (CMS) experiment stumbled on an unexpected phenomenon.

    CERN CMS Detector
    CMS

    Physicists smashed protons into lead nuclei at nearly the speed of light, which caused hundreds of particles to erupt from these collisions. But that wasn’t the surprise. What was surprising is where these particles went: Rather than spreading out evenly in all directions, the particles coming out of the collisions preferentially lined up in a specific direction.

    Now, the Rice team has co-authored a paper that describes the unexpected particle interactions from these proton and lead-nuclei collisions.

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    Rice undergraduate student Benjamin Tran, graduate student Michael Northup, postdoctoral student Maxime Guilbaud and graduate students Zhenyu Chen and Zhoudunming Tu were part of the Rice team of physicists on the Large Hadron Collider’s Compact Muon Solenoid experiment that co-authored a paper describing the unexpected particle interactions from proton and lead-nuclei collisions. (Photo by Zhoudunming Tu)

    Particle detectors are shaped a little like a soup can. In these kinds of collisions, there is a tendency for particles to amass in a line along the axis of the can known as a “ridge.” Up until now, physicists understood a lot about what happens when a pair of protons or a pair of lead nuclei collide, but not a lot about what happens when a proton hits a lead nucleus: Would the hot nuclear matter coming out of the collision act like protons colliding, in which the post-collision particles coast along without feeling the effect of their neighbors? Or would the particles coming out of proton and lead collisions act in a more collective, liquid-like way as in lead-nuclei collisions?

    In the recent Physical Review Letters paper, Rice physicists and co-authors returned to this mystery with more data than ever before. Physics Professor Wei Li, who discovered the phenomenon, led the team of scientists who analyzed the new data. They found that the data strongly supported that the matter coming out of these proton and lead collisions acts more like a liquid. This result was surprising because when the proton hits the lead nucleus, it punches a hole through much of the nucleus, like shooting a rifle at a watermelon (as opposed to colliding two lead nuclei, which is like slamming two watermelons together). Wei and his collaborators studied this surprising behavior by looking at six or eight particles simultaneously and how their directions correlated. This method is far more sensitive for identifying liquid-like behavior than the older method, which looked at particles two at a time. Li’s group also developed an algorithm called a trigger that records a small number of important collisions in the CMS detector among billions of candidates, allowing the researchers to efficiently investigate this interesting phenomenon.

    The data used in this analysis was recorded in March 2013 before the LHC stopped operations for refurbishments, retrofits and upgrades. This past June the LHC resumed operations with a 60 percent increase in collision energy. In December of this year, Li’s group will reconfigure the LHC accelerator to collide lead nuclei and see what sort of surprises this increase in collision energy will bring.

    This study helps scientists characterize a state of matter called a “quark-gluon plasma,” or QGP. This is similar to the familiar solid, liquid and gaseous states of matter, but much hotter. A QGP occurs when matter is heated to temperatures high enough to literally melt protons and neutrons at the center of atomic nuclei; the last time that a QGP was common in the universe was a mere millionth of a second after the Big Bang. The liquid-like nature of the QGP was a surprise to scientists, as they predicted a more gaseous-like behavior. Learning more about quark-gluon plasma will teach us something significant about the birth of the universe itself.

    See the full article here.

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    Rice U campus

    In his 1912 inaugural address, Rice University president Edgar Odell Lovett set forth an ambitious vision for a great research university in Houston, Texas; one dedicated to excellence across the range of human endeavor. With this bold beginning in mind, and with Rice’s centennial approaching, it is time to ask again what we aspire to in a dynamic and shrinking world in which education and the production of knowledge will play an even greater role. What shall our vision be for Rice as we prepare for its second century, and how ought we to advance over the next decade?

    This was the fundamental question posed in the Call to Conversation, a document released to the Rice community in summer 2005. The Call to Conversation asked us to reexamine many aspects of our enterprise, from our fundamental mission and aspirations to the manner in which we define and achieve excellence. It identified the pressures of a constantly changing and increasingly competitive landscape; it asked us to assess honestly Rice’s comparative strengths and weaknesses; and it called on us to define strategic priorities for the future, an effort that will be a focus of the next phase of this process.

     
  • richardmitnick 1:00 pm on June 8, 2015 Permalink | Reply
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    From BNL: “Scientists See Ripples of a Particle-Separating Wave In Primordial Plasma” 

    Brookhaven Lab

    June 8, 2015
    Karen McNulty Walsh

    Key sign of quark-gluon plasma (QGP) and evidence for a long-debated quantum phenomenon

    1
    Off-center collisions of gold ions create a strong magnetic field and set up a series of effects that push positively charged particles to the poles of the football-shaped collision zone and negatively charged particles to the “equator.” This charge separation is evidence for the existence of a “chiral magnetic wave” formed in the quark-gluon plasma created at RHIC.

    Scientists in the STAR collaboration at the Relativistic Heavy Ion Collider (RHIC), a particle accelerator exploring nuclear physics and the building blocks of matter at the U.S. Department of Energy’s Brookhaven National Laboratory, have new evidence for what’s called a “chiral magnetic wave” rippling through the soup of quark-gluon plasma created in RHIC’s energetic particle smashups.

    The presence of this wave is one of the consequences scientists were expecting to observe in the quark-gluon plasma—a state of matter that existed in the early universe when quarks and gluons, the building blocks of protons and neutrons, were free before becoming inextricably bound within those larger particles. The tentative discovery, if confirmed, would provide additional evidence that RHIC’s collisions of energetic gold ions recreate nucleus-size blobs of the fiery plasma thousands of times each second. It would also provide circumstantial evidence in support of a separate, long-debated quantum phenomenon required for the wave’s existence. The findings are described in a paper that will be highlighted as an Editors’ Suggestion in Physical Review Letters.

    To try to understand these results, let’s take a look deep within the plasma to a seemingly surreal world where magnetic fields separate left- and right-“handed” particles, setting up waves that have differing effects on how negatively and positively charged particles flow.

    “What we measure in our detector is the tendency of negatively charged particles to come out of the collisions around the ‘equator’ of the fireball, while positively charged particles are pushed to the poles,” said STAR collaborator Hongwei Ke, a postdoctoral fellow at Brookhaven. But the reasons for this differential flow, he explained, begin when the gold ions collide.

    The ions are gold atoms stripped of their electrons, leaving 79 positively charged protons in a naked nucleus. When these ions smash into one another even slightly off center, the whole mix of charged matter starts to swirl. That swirling positive charge sets up a powerful magnetic field perpendicular to the circulating mass of matter, Ke explained. Picture a spinning sphere with north and south poles.

    Within that swirling mass, there are huge numbers of subatomic particles, including quarks and gluons at the early stage, and other particles at a later stage, created by the energy deposited in the collision zone. Many of those particles also spin as they move through the magnetic field. The direction of their spin relative to their direction of motion is a property called chirality, or handedness; a particle moving away from you spinning clockwise would be right-handed, while one spinning counterclockwise would be left-handed.

    2
    The STAR detector at RHIC tracks particles emerging from thousands of subatomic smashups per second.

    According to Gang Wang, a STAR collaborator from the University of California at Los Angeles, if the numbers of particles and antiparticles are different, the magnetic field will affect these left- and right-handed particles differently, causing them to separate along the axis of the magnetic field according to their “chiral charge.”

    “This ‘chiral separation’ acts like a seed that, in turn, causes particles with different charges to separate,” Gang said. “That triggers even more chiral separation, and more charge separation, and so on—with the two effects building on one another like a wave, hence the name ‘chiral magnetic wave.’ In the end, what you see is that these two effects together will push more negative particles into the equator and the positive particles to the poles.”

    To look for this effect, the STAR scientists measured the collective motion of certain positively and negatively charged particles produced in RHIC collisions. They found that the collective elliptic flow of the negatively charged particles—their tendency to flow out along the equator—was enhanced, while the elliptic flow of the positive particles was suppressed, resulting in a higher abundance of positive particles at the poles. Importantly, the difference in elliptic flow between positive and negative particles increased with the net charge density produced in RHIC collisions.

    According to the STAR publication, this is exactly what is expected from calculations using the theory predicting the existence of the chiral magnetic wave. The authors note that the results hold out for all energies at which a quark-gluon plasma is believed to be created at RHIC, and that, so far, no other model can explain them.

    The finding, says Aihong Tang, a STAR physicist from Brookhaven Lab, has a few important implications.

    “First, seeing evidence for the chiral magnetic wave means the elements required to create the wave must also exist in the quark-gluon plasma. One of these is the chiral magnetic effect—the quantum physics phenomenon that causes the electric charge separation along the axis of the magnetic field—which has been a hotly debated topic in physics. Evidence of the wave is evidence that the chiral magnetic effect also exists.” Tang said.

    The chiral magnetic effect is also related to another intriguing observation at RHIC of more-localized charge separation within the quark-gluon plasma. So this new evidence of the wave provides circumstantial support for those earlier findings.

    Finally, Tang pointed out that the process resulting in propagation of the chiral magnetic wave requires that “chiral symmetry”—the independent identities of left- and right-handed particles—be “restored.”

    “In the ‘ground state’ of quantum chromodynamics (QCD)—the theory that describes the fundamental interactions of quarks and gluons—chiral symmetry is broken, and left- and right-handed particles can transform into one another. So the chiral charge would be eliminated and you wouldn’t see the propagation of the chiral magnetic wave,” said nuclear theorist Dmitri Kharzeev, a physicist at Brookhaven and Stony Brook University. But QCD predicts that when quarks and gluons are deconfined, or set free from protons and neutrons as in a quark-gluon plasma, chiral symmetry is restored. So the observation of the chiral wave provides evidence for chiral symmetry restoration—a key signature that quark-gluon plasma has been created.

    “How does deconfinement restore the symmetry? This is one of the main things we want to solve,” Kharzeev said. “We know from the numerical studies of QCD that deconfinement and restoration happen together, which suggests there is some deep relationship. We really want to understand that connection.”

    Brookhaven physicist Zhangbu Xu, spokesperson for the STAR collaboration, added, “To improve our ability to search for and understand the chiral effects, we’d like to compare collisions of nuclei that have the same mass number but different numbers of protons—and therefore, different amounts of positive charge (for example, Ruthenium, mass number 96 with 44 protons, and Zirconium, mass number 96 with 40 protons). That would allow us to vary the strength of the initial magnetic field while keeping all other conditions essentially the same.”

    See the full article here.

    Please help promote STEM in your local schools.

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    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 6:09 am on May 8, 2015 Permalink | Reply
    Tags: , , , , Quark-gluon plasma   

    From FNAL: Don Lincoln on Quark-Gluon Plasma 

    FNAL Home

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    Matter is malleable and can change its properties with temperature. This is most familiar when comparing ice, liquid water and steam, which are all different forms of the same thing. However beyond the usual states of matter, physicists can explore other states, both much colder and hotter. In this video, Fermilab’s Dr. Don Lincoln explains the hottest known state of matter – a state that is so hot that protons and neutrons from the center of atoms can literally melt. This form of matter is called a quark gluon plasma and it is an important research topic being pursued at the LHC.

    CERN LHC MapCERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN


    Download is available at the full article link below.

    Watch, enjoy, learn.

    See the full article here.

    Please help promote STEM in your local schools.

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 5:35 am on March 17, 2015 Permalink | Reply
    Tags: , , , , , Quark-gluon plasma,   

    From New Scientist: “Quark stars: How can a supernova explode twice?” 2013 But Well Worth the Read 

    NewScientist

    New Scientist

    09 December 2013
    Anil Ananthaswamy

    What do you get when you melt a neutron star? An unimaginably dense lump of strange matter and a whole new celestial beast

    1
    (Image: Matt Murphy)

    ON 22 September last year, the website of The Astronomer’s Telegram alerted researchers to a supernova explosion in a spiral galaxy about 84 million light years away. There was just one problem. The same object, SN 2009ip, had blown up in a similarly spectacular fashion just weeks earlier. Such stars shouldn’t go supernova twice, let alone in quick succession. The thing was, it wasn’t the only one, the next year another supernova, SN 2010mc, did the same.

    One of the few people not to be bamboozled was Rachid Ouyed. “When I looked at those explosions, they were talking to me right away,” he says. Ouyed, an astrophysicist at the University of Calgary in Alberta, Canada, thinks that these double explosions are not the signature of a supernova, but something stranger. They may mark the violent birth of a quark star, a cosmic oddity that has only existed so far in the imaginations and equations of a few physicists. If so they would be the strongest hints yet that these celestial creatures exist in the cosmic wild.

    The implications would be enormous. These stars would take pride of place alongside the other heavenly heavyweights: neutron stars and black holes. They could help solve some puzzling mysteries related to gamma-ray bursts [GRBs] and the formation of the heftiest elements in the universe. Back on Earth, quark stars would help us better understand the fundamental building blocks of matter in ways that even machines like the Large Hadron Collider cannot.

    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    Astrophysicists can thank string theorist Edward Witten for quark stars. In 1984, he hypothesised that protons and neutrons may not be the most stable forms of matter.

    Both are made of two types of smaller entities, known as quarks: protons are comprised of two “up” quarks and one “down” quark, whereas neutrons are made of two downs and one up. Up and down are the lightest of six distinct “flavours” of quark. Add the third lightest to the mix and you get something called strange quark matter. Witten argued that this kind of matter may have lower net energy and hence be more stable than nuclear matter made of protons and neutrons.

    Quark nova

    If so, we might all start decaying into strange matter. But don’t fret. You either need to wait around longer than the age of the universe for the stuff to form spontaneously, or find somewhere with the right conditions to start the process. One place this could happen is inside neutron stars, the dense remnants of certain types of supernovae.

    When a star many times more massive than the sun runs out of fuel, its inner core implodes. The outer layers are cast off in a spectacular explosion. What’s left behind is a rapidly spinning neutron star, which as the name implies is made mainly of neutrons, with a crust of iron. Whirling up to 1000 times per second, a neutron star is constantly shedding magnetic fields. Over time, this loss of energy causes the star to spin slower and slower. As it spins down, the centrifugal forces that kept gravity at bay start weakening, allowing gravity to squish the star still further.

    In what is a blink of an eye in cosmic time, the neutrons can be converted to strange quark matter, which is a soup of up, down and strange quarks. In theory, this unusual change happens when the density inside the neutron star starts increasing. New particles called hyperons begin forming that contain at least one strange quark bound to others.

    However, the appearance of hyperons marks the beginning of the end of the neutron star. “Once you start to form hyperons, then you can start the nucleation of the first droplet of strange quark matter,” says Giuseppe Pagliara of the University of Ferrara in Italy. As the density in the core continues to increase, the star’s innards “melt”, freeing quarks from their bound state. In fact, a single droplet of strange matter is enough to trigger a runaway process that converts all the neutrons. What was a neutron star turns into a quark star.

    Of course, this assumes that Witten is correct about strange quark matter being more stable than neutrons. No one has yet proved him wrong, but it is a tough idea for some to swallow. “More conservative thinkers are just not open to the idea that free quarks exist in neutron stars,” says Fridolin Weber, an astrophysicist at the San Diego State University in California.

    Not so the daring ones. Ouyed, for instance, has been trying to convince his fellow astrophysicists of the existence of quark stars for more than a decade. Not only do these intrepid few think that quarks can exist freely inside neutron stars, they have even thought about what comes next. “We all agree that if quark stars exist, then the conversion of normal, ordinary matter into a quark star will be a very exothermic process, a lot of energy will be released,” says Pagliara. “How this energy is released is a matter of debate.”

    On one hand, Pagliara and his colleagues have done extensive simulations to show that this conversion will happen in a matter of milliseconds. In what he calls a “strong deflagration”, the neutron star burns up as it turns into a quark star. There is no explosion.

    Ouyed, on the other hand, begs to differ. His team’s simulations show that the conversion is most likely to be an extremely violent process. The seed of strange quark matter spreads until it reaches the outer crust of the neutron star. As the part of the star that has been turned into quark matter separates from the iron-rich crust, it collapses. The collapse halts when the inner core becomes incredibly dense and rebounds, creating a shock wave. Much as in a supernova, the iron-rich crust and leftover neutrons are ejected in another spectacular explosion – a “quark nova”.

    Hurtling through space, the quark nova ejecta then slam into the earlier supernova remnants, causing them to light up again, as they did after the explosion of the original, conventional star. What’s left behind is a quark star. “It was very hard to find solutions where the entire neutron star turned into a quark star, in just a puff with no explosion,” says Ouyed.

    Double explosion

    Depending on the mass of the star before its first explosion, the second blast could occur anywhere from seconds to years after the original supernova. Too soon, and the two explosions would merge, appearing as one blast, smeared out in time. Too late, and the supernova ejecta would have dispersed long before the detonation of the quark nova, and there would be no re-brightening.

    But if the timing is just right, the outcome should be observable. In 2009, Ouyed’s team predicted that if the quark nova goes off days or weeks after the supernova, there should be two peaks in energy: the first being the supernova explosion itself, and the second being the reheating of the supernova ejecta. The objects SN 2009ip and SN 2010mc matched predictions in ways almost too good to be true.

    SN 2009ip had its first major explosion in early August 2012, and 40 days later flared up again. SN 2010mc was eerily similar in its outbursts, showing a double explosion in which the peaks were about 40 days apart. While other researchers continue trying to explain these unusual observations using their tried-and-tested models of supernovae, Ouyed is convinced that we have witnessed quark stars being born.

    Oddly, it is the first peak in both events that convinces him. If these have all the characteristics of a regular supernova, it makes the second boom harder to explain using conventional arguments. “When you look at the first ejecta, it looks like a duck and walks like a duck: it’s a supernova,” says Ouyed. “Then what’s the second one?”

    He points the finger at quark novae. “We just applied our model of the dual shock quark nova, and it was actually easy to fit,” he says. “That’s the beauty of it.”

    While Pagliara and Ouyed’s teams disagree on whether the transition from a neutron star to a quark star is explosive, they do agree that space should be littered with quark stars. How should we look for them?

    We might be mistaking some of them for neutron stars, says Pagliara. Most neutron stars weigh as much as 1.4 suns or slightly more. The best studied examples, orbiting each other in systems called Hulse-Taylor binary pulsars, certainly follow this pattern. Both neutron stars involved weigh in at 1.4 solar masses. However, Pagliara is bothered by two discoveries of neutron stars that tip the scales at 2 solar masses each. “It’s difficult to reach this mass with normal particle components like neutrons, protons and hyperons,” he says.

    This has to do with a property of matter called its equation of state. Equations of state describe how matter behaves under changes in physical conditions, such as pressure and temperature. Hyperons, which are precursors to strange quark matter, have a “soft” equation of state. Their existence in the dense core of a neutron star makes the star more compressible, causing it to shrink in size.

    Astronomers estimate that neutron stars are about 10 kilometres across – but squeezing 2 solar masses into an object of such size would end up creating a black hole. Pagliara says that compact stars weighing 2 solar masses or more have to be bigger, or put another way, the matter has to be “stiffer” so that gravity cannot compress it as much. There is one candidate with a stiffer equation of state: strange quark matter.

    Pagliara and his colleague Alessandro Drago and others claim that the compact stars we have spotted come from two families. The smaller ones must be the run-of-the-mill neutron stars. The larger ones must be quark stars. The only way to verify this claim is to measure their masses and also measure their radii to the nearest kilometre. A proposed European satellite mission called the Large Observatory for X-ray Timing could do just that. Its aim is to measure the equation of state for compact objects – and thus differentiate between neutron stars and quark stars.

    ESA LOFT
    ESA/LOFT

    Meanwhile, Ouyed’s team is concentrating on predictions based on their quark nova model. One prediction has to do with the creation of heavy elements in the universe. Once a massive star goes supernova, weighty elements are synthesised in a matter of milliseconds, when neutrons are absorbed into iron nuclei. These neutron-rich nuclei are unstable and decay into elements further up in the periodic table when neutrons get converted to protons. “But the challenge with supernovae has always been to go to really heavy elements,” says Ouyed. The iron and neutrons needed for the process are in short supply because most of them are left behind in the remnant neutron star.

    The quark nova solves that problem. Its ejecta are a potent mix of neutrons and iron from the neutron star’s crust, providing just the laboratory for synthesising the heaviest elements. Ouyed is urging astronomers to study double explosions carefully. His team predicts that the second blast should show the presence of elements heavier than atomic mass 130, elements which should be missing from the first explosion.

    The conversion of a neutron star to a quark star could also solve another problem plaguing astrophysics: the source of some long-duration gamma-ray bursts, which are among the brightest events in the universe. On 9 July 2011, NASA’s SWIFT gamma-ray satellite saw a burst with two spectacular peaks of emission, spaced 11 minutes apart.

    NASA SWIFT Telescope
    NASA/Swift

    And the second was the stronger of the two. The traditional “collapsar” model of gamma-ray bursts relies on a star collapsing to a black hole. As the last remnants of the doomed star fall in, it is thought to result in such an emission. But 11 minutes is an eternity for a black hole – it’s hard to make sense of the second peak.

    Pagliara thinks his team has the answer. According to their model, a neutron star converts to a quark star without an explosion. Yet there is still a tremendous release of energy, which Pagliara suspects goes into gamma rays. This could explain the second peak. “At the moment, and it’s speculation, we think that this second event could be related to quark stars,” he says. “If you want to see a possible signature of formation of quark matter, you should probably look at those gamma-ray bursts that have an activity long after the main event.”

    Quark world

    Confirming the existence of quark stars and verifying their properties could have a huge impact on particle physics. Colliders like the LHC and the Relativistic Heavy Ion Collider (RHIC) in Brookhaven National Laboratory [BNL]in New York have been smashing heavy ions head-on to create a state of matter called a quark-gluon plasma, where quarks are essentially free.

    BNL RHIC Campus
    BNL RHIC
    RHIC at BNL

    The best way to study this phase of matter is using a method called lattice quantum chromodynamics [QCD]. But physicists have only been able to solve the equations of lattice QCD for high temperatures and low density – the conditions created at the LHC and the RHIC. The equations are intractable for other conditions. For instance, it is impossible to calculate the density at which protons and neutrons can melt into their constituent quarks at low temperatures.

    Enter quark stars. First, if their existence is confirmed, it proves that quarks can exist freely at high densities and low temperatures, rather than bound up in hadrons – the catch-all name given to any particle made of quarks. Second, for the explosive quark nova model Ouyed’s team has shown that the density at which quarks get freed is intimately linked to the time lag between the supernova and the quark nova. Measure the timing of the double explosion and you will glean important clues about conditions at the transition. “The quark nova is a very beautiful bridge that straddles the hadronic world and the quark world,” says Ouyed. “It’d be a very nice tool to use for physics and astrophysics.”

    Weber agrees that quark stars, if they exist, would be a unique astrophysical laboratory. They would help us probe properties of matter in ways that we cannot do with the best colliders on Earth – in the domain of high densities and low temperatures. “This is a regime that is only accessible to stars, and only stars can tell us what will happen.”

    See the full article here.

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  • richardmitnick 9:02 pm on January 8, 2015 Permalink | Reply
    Tags: , , Quark-gluon plasma   

    From Perimeter: “A simpler way to understand ultra-hot chaos” 

    Perimeter Institute
    Perimeter Institute

    January 8, 2015
    Tenille Bonoguore

    Perimeter researcher Michal P. Heller has created a shortcut to understand primordial matter in its most extreme state.

    To recreate the birth of the universe, most physicists believe that you would first need a big bang. This would be followed almost instantly by the appearance of an ultra-hot blob of plasma, the primordial soup that formed the basis of everything in existence.


    Quark-gluon plasma

    It’s not exactly a process that is easily replicated, but in heavy-ion colliders, experimentalists are creating “little bangs” to produce tiny droplets of quark-gluon plasma (QGP).

    The experiments offer a glimpse of the kind of matter that filled the early universe, but there’s a problem. In its earliest stages – between “bang” and “goop” – the system is in extreme distortion. In fact, it’s not until the system cools down that it reaches equilibrium and can be assessed.

    It is this period of ultra-hot chaos that intrigues Perimeter Institute postdoctoral researcher Michal P. Heller. And in a new paper published recently in Physical Review Letters, he has brought together two seemingly different fields of study – hydrodynamics and string theory – to help describe it.

    In ordinary matter, quarks do not exist in isolation; they are always bound extremely tightly by gluons in atomic nuclei. But in extreme conditions – say, in temperatures a million times hotter than the sun – these bonds can “melt,” forming an ultra-hot, almost-frictionless plasma in which quarks and gluons move freely.

    QGP has recently been created by smashing atomic nuclei against each other at the Relativistic Heavy-Ion Collider at the Brookhaven National Laboratory in the United States, and at the Large Hadron Collider at CERN in Switzerland.

    BNL RHIC
    BNL RHIC Campus
    RHIC at BNL

    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    The tiny droplets produced by these “little bangs” exist for brief flashes of time, like super-hot fireballs that quickly expand and cool into ordinary matter. In the moment after the collision, the ultra-hot system is in extreme distortion, existing at the threshold of being called a fluid.

    Despite the fact that theorists know the microscopic rules that govern such ultra-energetic collisions, questions still abound. It is clear these systems only become plasma once they settle enough to reach equilibrium. Working out what happens in the chaotic interim, before the system equilibrates, requires extremely complex computations.

    The standard modelling for plasma experiments uses relativistic hydrodynamics, a theory similar to that describing the motion of water but which also incorporates [Albert] Einstein’s special relativity. (This is because QGP and its microscopic constituents move with large velocities, at which relativistic effects become important.)

    Some researchers, including Heller, have simplified the problem by equating the relaxation of the QGP “fireball” to a black hole reaching equilibrium in a hypothetical five-dimensional space. This approach takes methods derived from string theory, and applies them to the physics of the “little bang” experiments and the droplets of QGP they create.

    Now, Heller and his co-authors have put forward a computational technique that is something of a further short-cut for theorists: instead of doing the calculations using five-dimensional Einstein equations – which is very complicated – they have developed a way to incorporate part of those calculations into a four-dimensional description that is coupled to conventional hydrodynamics equations.

    “The paper shows something about the theories of relativistic hydrodynamics that was known, but not many people had thought about it seriously,” Heller says. “Our observation opens up a new possibility of describing transient relaxation effects governing the approach to the quark-gluon plasma phase.”

    This work is a return of sorts for Heller, a Polish scientist who came to Perimeter in 2014 from the University of Amsterdam. His research career began with a 2007 paper studying theories of second-order relativistic hydrodynamics, which factors causal evolution into standard fluid dynamics. In 2012 and 2013, his work in string theory and strong gravity brought him back to those theories, but with a new perspective.

    “What’s been fun is coming back to the project I started my research career with, and realizing that the things which I thought several years ago were simple are actually not so trivial and have far-reaching consequences,” he says.

    When he was younger, he thought the universe could be understood through one simple model. Now, he sees much more nuance: “At some point, you start appreciating that everything is complex and interconnected.”

    QGP is like that, too, he says. While researchers would probably like to create QGP in a simple state of equilibrium (so that they can introduce their own distortions and measure the effects), reality is much more complex. Current experimental and theoretical approaches aren’t sensitive enough to capture and analyze in detail the droplets’ initial, highly distorted state, but Heller’s paper is a step in this direction.

    “Is that a choice? It’s more of a necessity, at least given what we have available here on Earth,” he says.

    Should other researchers build on this work, combining it with complementary approaches of initial state physics to construct some sort of a hybrid, he says these generalized theories of hydrodynamics “will be a crucial ingredient of whatever comes next.”

    See the full article here.

    Please help promote STEM in your local schools.

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    About Perimeter

    Perimeter Institute is a leading centre for scientific research, training and educational outreach in foundational theoretical physics. Founded in 1999 in Waterloo, Ontario, Canada, its mission is to advance our understanding of the universe at the most fundamental level, stimulating the breakthroughs that could transform our future. Perimeter also trains the next generation of physicists through innovative programs, and shares the excitement and wonder of science with students, teachers and the general public.

     
  • richardmitnick 3:12 pm on October 10, 2014 Permalink | Reply
    Tags: , Quark-gluon plasma,   

    From Science Friday via BNL: "How to Make Quark Soup" 

    Brookhaven Lab

    scifri

    Watch, enjoy, learn

    BNL Campus

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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