new states of strongly interacting astrophysical matter pitp conference 2005 mannque rho (saclay)
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New States of New States of Strongly Strongly
Interacting Interacting Astrophysical Astrophysical
MatterMatterPITP Conference 2005PITP Conference 2005
Mannque Rho (Saclay)
Where does the mass Where does the mass come from?come from?
Molecules, Atoms, Nuclei: Masses =sum of masses of constituents + tiny binding energy Constituents: protons, neutrons, electrons
Nuclear BE < 1%
Mysteries abound in the Mysteries abound in the Standard Model and Standard Model and
Beyond…Beyond…
Where do the quark, lepton etc.Where do the quark, lepton etc. masses come from?masses come from?
.. Etc….. Etc… Where do the “dark stuff” in the Where do the “dark stuff” in the
Universe come from?Universe come from? .. Etc….. Etc…
For someone else!
Mass right around usMass right around us
•Proton/Neutron Mass=938/940 MeV
Constituents: Quarks and gluons
• Proton= uud ; Neutron= udd
Sum of “current-quark” masses ≈ 10 MeV
Where do ~ 99% of the mass come from?
QCD Answer QCD Answer
“ Energy stored in the motion of the (nearly) massless quarks and energy in massless gluons that connect them”
Proton mass ≈ 1 GeV
“Mass without mass”
• Technically, “chiral symmetry spontaneously broken SB)”
• QCD on lattice explains the proton mass within ~ 10% .
Order ParameterOrder Parameter
Quark condensate: <qq>_
• <qq> ≈ - (0.23±0.03 GeV)3→ Proton mass ≈ 1 GeV• What happens when <qq>→ 0 ?
≠ 0 S broken= 0 S restored
_
_
The QuestionThe Question
If the mass is generated by dynamical“dressing,” can it be made to disappear by“undressing” in the laboratories ?
Or can one dial the mass to zero?
Yes! through dialing thecondensate to zero
LatticeQCD
(Two) Surprises(Two) Surprises
• At High Density (Gravity): Kaon condensation
• At High Temperature (Heavy-Ion Collisions): Nearly perfect liquid
New “unexpected” states are found
Effective Field TheoriesEffective Field Theories
QCD cannot address directly the problem ofgoing toward the critical point Tc/nc, so weneed to resort to effective field theories
Tools at our disposal: • NLNonlinear sigma model with pseudo- Goldstone bosons (K, …) • HLS: Hidden local symmetry model with light vectors (K*, …)etc …
In Favor of HLSIn Favor of HLS• AdS/QCD indicates a 5-D pure gauge theory giving in 4-D a tower of vector mesons and a multiplet of Goldstone bosons describing QCD in nonperturbative regime• Baryons emerge as skyrmions to complete the degrees of freedom required• With a suitable truncation and in the chiral limit (quark masses=0), the theory can arrive at the critical point as a fixed point known as “Vector Manifestation (VM)”
Predictions with HLSPredictions with HLS
As <qq>→ 0, i.e., n (or T)→ nc (or Tc)
Theory well defined at this limit! Hidden gauge coupling g <qq> → 0 Pion decay constant fF(<qq>) → 0 Even away from the limit, hadron mass (except for ’s) satisfies “BR scaling”; e.g., in density m(n)/m(0) ≈ fn)/ffor n ≤ n0
≈ g(n)/g(0) for n > n0
where n0 = 0.16 fm-3 nuclear matter
¯¯
¯
NatureNature
There are indications thatthe scaling is operative up to n0
mn0)/m≈ fn0)/f≈ 0.8
Bonn: CBELSA/TAPS CollaborationA→X→+X’
KEK:Deeply boundpionic nuclei
A dense new state above A dense new state above nn00
It is certain that the interior of neutron starsis much denser than nuclear matter:Can one create such a dense system in the laboratories?
Answer (T. Yamazaki et al, KEK): Capture anti-strangeness (e.g. K- ) inside nuclei
MechanismMechanismTurns out to be surprisingly simple
Huge attraction from two main sources:• Attractive K- - nuclear interaction
K
A
- (1/fdensity ≡ - A
• Density counters ESB, tending to restore S
- c KN density ≡ - B
A+B ~ 200 MeV at n n0 =0.16 fm-3
Discovery of strangeness Discovery of strangeness nuggetnugget
A bound pnnK – = “ S0 (3115)” BE=mp + 2mn + mK – mS
=194 ± 5 MeV
Average density ~ 3 n0
KEK 2004
Strong binding overcomescompression energy!
Kaon condensation in Kaon condensation in neutron starsneutron stars
How the nugget is stabilized is not yet understood.However if the same mechanism is applied to (infinite) neutron star matter, kaons will condense
mK*
e
e- → K- + nC ≥ nNugget
n
ObservationObservation
For a suitable set of parameters, kaon condensation occurs at a density slightly above that of the nugget S0 (3115) . It has one proton and two neutrons per each condensed kaon just like the S0 (pnnK-) .
ConsequencesConsequences
Kaons condense before chiral symmetry is Kaons condense before chiral symmetry is restored and before color superconductivity restored and before color superconductivity can set in.can set in.
Condensed kaons soften EOS. An intriguing Condensed kaons soften EOS. An intriguing possibility a la Bethe and Brown: Compact possibility a la Bethe and Brown: Compact stars with mass greater than ~ 1.5 times the stars with mass greater than ~ 1.5 times the solar mass undergo gravitational collapse solar mass undergo gravitational collapse maximum stable neutron star mass ~ 1.5 maximum stable neutron star mass ~ 1.5 solar mass. solar mass.
So far no strong cases against the BB So far no strong cases against the BB scenario exists.scenario exists.
Ideal liquid above Ideal liquid above TTc c (?)(?)
Standard lore based on asymptotic freedom: Weakly-coupled quark-gluon plasma above Tc
(CERN announcement)
State of matter 10-6 s after the “Big Bang”:
Heavy Ion
Lattice calculation & RHIC experiments indicate: Not a gasof quarks and gluons but
• Possibly an “ideal” liquid with viscosity/entropy /s ~ 1/4*, ~ 400 times smaller than (/s)water.
• A strongly coupled system much like black hole horizons
• Just above TC , strongly bound states of light a1
saturate the entropy.
Conjectured bound (a la Kovtun, Son and Starinets) based on holgraphic duality*