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Theory of (strongly coupled) quark-gluon plasma (sQGP). From RHIC to LHC (31st J.Hopkins workshop, Heidelberg, Aug.2007) Edward Shuryak Stony Brook. The emerging theory of sQGP. Quantum mechanics. Stronly coupled cold trapped atoms. Manybody theory. Lattice simulations. sQGP.
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Theory of (strongly coupled) quark-gluon plasma (sQGP) From RHIC to LHC (31st J.Hopkins workshop, Heidelberg, Aug.2007) Edward Shuryak Stony Brook
The emerging theory of sQGP Quantum mechanics Stronly coupled cold trapped atoms Manybody theory Lattice simulations sQGP Quasiparticles Potentials correlators Bound states of EQP and MQP J/psi,mesons,baryons,calorons Bose-Einstein Condensation -> confinement EoS Flux tubes-> RHIC data Hydrodynamics Molecular dynamics Monopoles Transport properties Plasma physics E/M duality Energy loss, Collective modes Mach cones AdS/CFT Gauge theories, SUSY models String theory
Outline Qs: Why do we have strongly coupled quark-gluon plasma (sQGP) at RHIC? Is it related to deconfinement (T=(1-1.5)Tc) or quasi-conformal behaviour at $T>1.5Tc? What is the role of magnetic objects? Can one explain RHIC results using AdS/CFT? A picture is emerging… • RHIC findings: collective flows and jet quenching • Viscosity and diffusion constant from AdS/CFT, complete gravity dual? • Phase diagram and lattice. Electric andmagneticquasiparticles (EQPs and MQPs) are fighting for dominance (J.F.Liao,ES, hep-ph/0611131,PRC 07)Flux tube existence/dissolution (J.F.Liao,ES, 0706.4465[hep-ph])molecular dynamics (MD) of Non-Abelian plasma with monopoles(B.Gelman, I.Zahed,ES, PRC74,044908,044909 (2006), J.F.Liao,ES, hep-ph/0611131,PRC 07) • trasport summary=> • What should one find at LHC? summary
RHIC findings • Strong radial and elliptic flows are very well described by ideal hydro => ``perfect liquid” • Strong jet quenching, well beyond pQCD gluon radiation rate, same for heavy charm quarks (b coming) • Jets destroyed and their energy goes into hydrodynamical ``conical flow”
From Magdeburg hemispheres (1656) to dreams of 1970’s… (air pumped out from Magdeburg hemispheres by von Guericke) • “We cannot pump the QCD vacuum out, but we can pump in something else, namely the Quark-Gluon Plasma, and measure explosion” • (QGP in 1970’s was expected to be just a simple near-ideal quark-gluon gas, to ``fill the bag”)
One may have an absolutely correct theory and stillmake accidental discoveries… Columbus believed if he goes west he should eventually come to India But something else was on the way… We believed if we increase the energy density, we should eventually get weakly interacting QGP. But something else was found on the way, sQGP
How Hydrodynamics Works at RHIC Elliptic flow How does the system respond to initial spatial anisotropy? Dense or dilute? If dense, thermalization? If thermalized, EoS? )
The coolest thing on Earth, T=10 nK or 10^(-12) eV can actually produce a Micro-Bang ! (O’Hara et al, Duke ) Elliptic flow with ultracold trapped Li6 atoms, a=> infinity regime The system is extremely dilute, but can be put into a hydro regime, with an elliptic flow, if it is specially tuned into a strong coupling regime via the so called Feshbach resonance Similar mechanism was proposed (Zahed and myself) for QGP, in which a pair of quasiparticles is in resonance with their bound state at the “zero binding lines”
proton pion 2001-2005: hydro describes radial and elliptic flows for all secondaries , pt<2GeV, centralities, rapidities, A (Cu,Au)… Experimentalists were very sceptical but wereconvinced and ``near-perfect liquid” is now official, =>AIP declared this to be discovery #1 of 2005 in physicsv_2=<cos(2 phi)> PHENIX, Nucl-ex/0410003 red lines are for ES+Lauret+Teaney done before RHIC data, never changed or fitted, describes SPS data as well! It does so because of the correct hadronic matter /freezout via (RQMD)
One more surprize from RHIC: strong jet quenching and flow of heavy quarks nucl-ex/0611018 (submitted to Phys. Rev. Lett.) Heavy quark quenching as strong as for light gluon-q jets! Radiative energy loss only fails to reproduce v2HF. Heavy quark elliptic flow: v2HF(pt<2GeV) is about the same as for all hadrons! => Small relaxation time t or diffusion coefficient DHQinferred for charm.
Wake effect or “sonic boom” Sonic boom from quenched jetsCasalderrey,ES,Teaney, hep-ph/0410067; H.Stocker… • the energy deposited by jets into liquid-like strongly coupled QGP must go into conical shock waves • We solved relativistic hydrodynamics and got the flow picture • If there are start and end points, there are two spheres and a cone tangent to both
Two hydro modes can be excited(from our linearized hydro solution): a ``diffuson” a sound
PHENIX jet pair distribution Note: it is only projection of a cone on phi Note 2: more recent data from STAR find also a minimum in <p_t(\phi)> at 180 degr., with a value Consistent with background The most peripheral bin, here no matter
AdS/CFTfrom gravity in curved extra dimensions to strongly coupled CFT plasma • whatever people dream about for LHC, a black hole formation does happen, in each and every RHIC AuAu event =>thermalization (All info is lost except overall entropy, area of formed b.h.horizon)
viscosity from AdS/CFT(Polykastro,Son, Starinets 03)Kubo formula <Tij(x)T_ij(y)>=> • Left vertical line is our 4d Universe, (x,y are on it) • Temperature is given by position of a horizon (vertical line, separationg • From interier of``black brane” T=T(Howking radiation) (Witten 98) • Correlator needed is just a graviton propagator G(x,y) • Blue graviton path does not contribute to Im G, but the red graviton path (on which it is absorbed) does Both viscosity and entropy are proportional to b.h. horizon, thus such a simple asnwer
Heavy quark diffusion J.Casalderrey+ D.Teaney,hep-ph/0605199,hep-th/0701123 W O R L D One quark (fisherman) is In our world, The other (fish) in Antiworld (=conj.amplitude) String connects them and conduct waves in one direction through the black hole A N T I W O R L D
subsonic supersonic Left: P.Chesler,L.Yaffe Up- from Gubser et al Both groups made Amasingly detailed Description of the conical flow from AdS/CFT=> not much is diffused
Gravity dual to the whole collision: “Lund model” in AdS/CFT • Black Hole creation in heavy ion collisions (Nastase 03, Sin,ES and Zahed 04,Janik-Peschanski 05…) If colliding objects made of heavy quarks • Stratching strings -- unlike Lund model those are falling under the AdS gravity (Lin,ES hep-ph/0610168) and don’t breake! • The falling membrane is created which separate two regions of two different metrics: it is becoming a b.h. horizon Now linearized version in progress (field from a static Maldacena string recently done Lin,ES arXiv:0707.3135, T00 ->1/r7 ) AdS5 Center= Extremal b.h.
Explaining transport in sQGP:Classical QGP and its Molecular Dynamics Electrons have the same charge -e at all time, but our quasiparticles (quarks, gluons,…) have colors which is changing in time Fraction of quasiparticles are magnetically Charged (monopoles and dyons). At T<Tc they make a “dual superconductor” =>confinement. At T>Tc they fight each other
As Gamma= <|Epot|>/<Ekin> grows gas => liquid => solid • This is of course for +/- Abelian charges, • But ``green” and ``anti-green” quarks do the same! • local order would be preserved in a liquid also, • as it is in molten solts (strongly coupled TCP with • <pot>/<kin>=O(60), about 3-10 in sQGP)
Effective coupling is large! alphas=O(1/2-1) (not <0.3 as in pQCD applications)tHooft lambda=g2Nc=4piNc=O(20)>>1-1 Bielefeld-BNL lattice group: Karsch et al
An example of ``dyonic baryon”=finite T instantontop.charge Q=1 config.,dyons identified via fermionic zero modes Berlin group - Ilgenfritz et al Red,blue and green U(1) fields 3 dyons with corresp. Field strengths, SU(3), Each (1,-1,0) charges
Electric and magnetic scrreningMasses, Nakamura et al, 2004My arrow shows the ``self-dual” E=M point Me<Mm Magnetic Dominated At T=0 magnetic Screening mass Is about 2 GeV (de Forcrand et al) (a glueball mass?) There are more data (Karsch et al) Detailing how Me Vanishes at Tc Me>Mm Electrric dominated ME/T=O(g) ES 78 MM/T=O(g^2) Polyakov 79
New (compactified) phase diagramdescribing an electric-vs-magnetic competition Dirac condition (old QED-type units e^2=alpha, deliberately no Nc yet) <- n=2 adjoint Thus at the e=g line Near deconfinement line g->0 in IR (Landau’s U(1) asymptotic freedom) => e-strong-coupling because g in weak! Why is this diagram better? => There are e-flux tubes in allblue region, not only in the confined phase! In fact, they are maximally enhanced at Tc
Energy and entropy associated with 2 static quarksis very large near Tcfrom lattice potntials Bielefeld-BNL pQCD predicts a negative U • R->infinity means there are 2 separate objects • Entropy=20 implies exp(20) states • At R=(.3-1.2)fm both are about linear in R <= What object is that?
Energy and entropy associated with 2 static quarksis very large near Tcfrom lattice potntials Bielefeld-BNL pQCD predicts a negative U • R->infinity means there are 2 separate objects • Entropy=20 implies exp(20) states • At R=(.3-1.2)fm both are about linear in R <= What object is that?
e-flux tubes above Tc?(with J.F.Liao, archive 0706.4465 [hep-ph]) • Dual superconductivityat T<Tcas a confinement mechanism (‘tHooft, Mandelstam 1980’s) => monopole Bose condensation => electric flux tubes (dual to Abrikosov-Nielsson-Olesen vortices) • Can uncondenced MQPs do the same at T>Tc ?MQPs are reflected from a region with E field => pressure => flux tubes compression in plasma • We solve quantum mechanics of motion in each partial wave
magnetic flux tubes at the Sun,(work without any superconductor!): so we need to work out the exact conditions where classical electrons rotate around it • B: about 1 kG, • Lifetime: few months
Classical and quantum mechanics of the flux tube Red trajectory A => nu=0 (velocity at large r directed to the center) Black one B => m=0 (which goes through the center because no m^2/r^2 barrier)
MD simulation for plasma with monopoles (Liao,ES hep-ph/0611131)monopole admixture M50=50% etcagain diffusion decreases indefinitely, viscosity does not It matters: 50-50 mixture makes the best liquid, as it creates ``maximal confusion”
short transport summarylog(inverse viscosity s/eta)- vs. log(inverse heavy q diffusion const D*2piT) (avoids messy discussion of couplings) ->Stronger coupled -> • RHIC data: very small viscosity and D • vs theory - AdS/CFT and MD(soon to be explained) Most perfect liquid 4pi MD results, with specified monopole fraction Weak coupling end => (Perturbative results shown here) Both related to mean free path 50-50% E/M is the most ideal liquid
From RHIC to LHC:(no answers, only 1bn$ questions) • Will ``perfect liquid” be still there? • Is jet quenching as strong, especially for c,b quark jets and much larger pt? • Is matter response (conical flow at Mach angle) similar? (This is most sensitive to viscosity…)
From SPS to LHC • lifetime of QGP phase nearly doubles, but v2 grows only a little, to a universal value corresponding to EoS p=(1/3)epsilon • radial flow grows by about 20% => less mixed / hadronic phase(only 33% increase in collision numbers of hadronic phase in spite of larger multiplicity) (From S.Bass)
Strongly coupled QGP is produced at RHIC T=(1-2)Tc This is the region where transition from magnetic to electric dominance happen at T<1.4 Tc still Lots of magnetic objects => E-flux tubeseven without their condensate Classical MD is being done, lowest viscosity for 50-50% electric/magnetic plasma RHIC data on transport (eta,D), ADS/CFT and classical MD all qualitatively agree ! Conclusions • AdS/CFT => natural applications of string theory • N=4 SYM is nonconfining and • Strongly coupled! • small viscosity, and heavy quark diffusion, conical flow seen in detail!