1. Mannque Rho CEA Saclay Nuclear tensor forces and a signal for scale -chiral symmetry in nuclei 2 nd APCTP-ECT* Workshop 2015 What I would propose to work out at RAON

2. Monday’s talk Monday’s talk: a) Start with scale-invariant hidden local symmetry with dilaton  and pions  coupled to matter fields  and  subject to explicit symmetry breaking away from the IR fixed point and current quark masses. The degrees of freedom are the nucleons (N), the hidden gauge mesons  and a multiplet of pNG  and  ‘s. b)The effective Lagrangian is matched via correlators to QCD at the matching scale  M from which the EFT picks up IDD (intrinsic density dependence) from QCD condensates. c)Nuclear dynamics is described by “double decimation” RG flows from  M, the first decimation leading to V lowk endowed with IDD and the second to what corresponds to Fermi-liquid fixed point approach to many body problem. d) Monday’s talk was focused on dense matter, n > n 0.

3. This talk I will focus on processes near nuclear matter, in particular connected to nuclear tensor forces. I will then propose how to “see” the manifestation – i.e., a signal – of scale-chiral symmetry of QCD in nuclear medium. Perhaps in RAON-type physics!(?) Debate between Gerry Brown and Steven Weinberg in early 1990’s.

4. To go from soft-pion scale up to higher scale  At E ≈ 0, Soft pion/current algebra applies:  Notice An Invariance: This is a “redundancy”, exploit it to gauge the symmetry to “hidden local symmetry (HLS)” à la Harada and Yamawaki. Provides potentially powerful tool to go toward the vector meson scale. Write

5. Brown-Weinberg debate On EFT in nuclear physics Brown (espousing HLS): “the  meson is essential in nuclear physics”. Weinberg (espousing standard  ChPT): “the  is not needed, its effect can be incorporated in counter terms involving pions only” Weinberg’s “mended symmetry” acknowledges Brown’s thesis

6.  One vector meson: Georgi et al. 1999 Something deep about Something deep about HLS is involved in the debate Approaching QCD with effective fields involves Infinite towers of vector mesons as hidden gauge fields Moose construction by

7.  Two vector mesons …  Many (K=  ) vector mesons in “open moose”: where

8. And take continuum limit with K = ,  →0 : → 5D YM o Chiral symmetry in 4D is elevated to a local gauge symmetry in 5D. It also comes from string theory, e.g., Sakai and Sugimoto 2003. So at some mass scale, vector mesons must appear. But the question is: Is any of them essential in nuclear physics? The answer is most likely YES.

9. Tensor forces: Tensor forces: An old problem with a new twist

10.  NN What scale-chiral symmetry predicts for nuclear tensor forces What scale-chiral symmetry predicts for nuclear tensor forces IDD (intrinsic density dependence), representing matching of EFT and QCD, in the “bare” parameters of the EFT Lagrangian reflects the vacuum change in nuclear matter.

11. Crucial ingredient: chiral symmetry locked to scale symmetry Crucial ingredient: chiral symmetry locked to scale symmetry At  IR, in the chiral limit    D      =    A   0.   (“dialon”) and  (pseudo) NG bosons  f   f  Dilaton condensate provides IDD’s to EFT Lagrangian Crewther and Tunstall 2013

12. 2-phase baryon structure via topology n = density

13. Consequence on the nucleon mass “Emergent” parity-doublet symmetry for nucleons: m * = m 0 +    n 1/2 m 0  (0.6 – 0.8) m N Y.L. Ma et al 2013

14. IDDs drastically modify tensor forces For density n  n 1/2 : n=n 0 n=2n 0 n=0  The pion tensor is protected by chiral symmetry, so only the  tensor is affected by density. n 1/2 For density n < n 1/2 : IDD Net tensor decreasesNet tensor increases

15. Impact on EoS Impact on EoS For matter with excess of neutrons (i.e., neutron star) the “symmetry energy” E sym plays a dominant role.

16. E sym by closure approximation G.E. Brown and R. Machleidt n=n 0 n > n 1/2 n=0 Decreasing tensor Increasing tensor E sym is dominated by tensor forces n 1/2 cusp

17. E sym from half-skyrmion matter E sym from half-skyrmion matter The E sym calculated with the IDDs extracted from the topology change matches the E sym given by the order 1/N c (rotational quantized) skyrmion energy. This supports the robustness of using the topology change for the IDDs. H.K. Lee, B.Y. Park, R. 2010

18. n 1/2 E sym in V lowk Paeng, Kuo, Lee, R

19. Surprising things happen in Finite nuclei and nuclear matter

20. Use “Double decimation” There are roughly two RG decimations in nuclear many-body EFT a) Decimate from    to ~ (2-3) fm -1 or ~ 400 MeV up to which accurate NN scattering data are available, say, E lab ≤ 350 MeV. Call it  data. Yields V lowK b) Decimate from  data to Fermi surface scale  FS using V lowK operative up to E lab. This derives Fermi liquid fixed point theory valid for nuclear matter. Fluctuate around Fermi surface; Many body technique Bogner, Kuo et al, arXiv:nucl-th/0305035

21. V lowk - RG approach Kuo, Brown, Holt, Schwenk et al

22. Tensor forces are not renormalized !! Observation but no proof

23. Tom Kuo 2013 Non-renormalization of the tensor force In deuteron

24. Tom Kuo 2013

25. In second decimation Ring diagram summation À la Kuo et al.

26. Monopole matrix element Evolution of single-particle energy Tensor forces in shell evolution In exotic nuclei In exotic nuclei T. Otsuka 05

27. Tensor forces are important in complex nuclei

28. “V bare ”=“V lowk ”=“V Qbox ”

29. Conclusion In light as well as complex nuclei at low density involving no IDD, i.e.,. I take one step further and assume that the  remains zero independently of the IDD. This means that tensor forces with IDD’s for varying densities are non-renormalized.

30. How to “see” IDD  Tensor forces are “scale-independent” at any density, i.e., fixed-point quantity.  If one can dial the density, then tensor forces will offer a pristine signal for IDD free of renormalization.  Zero-in on processes probing tensor forces.

31. An “evidence”: C14 dating probes scaling An “evidence”: C14 dating probes scaling J.W. Holt et al, PRL 100, 062501 (08) n=0 n=n 0

33. Caveat? Many-body forces Caveat? Many-body forces (a) (b) (c) The long lifetime of C14 has also been explained by 3-body forces without IDD (Holt and Weise 2010, Maris et al 2011…). Way out: The contact 3-body force (c) is of the same mass-scale as IDD. In medium with HLS, it is encoded in the IDD. With  exchange, the contact term should be negligible.

34. What are the observables in RIB physics that can zero-in -- like in the C14 case – on tensor forces acting in varying density regimes? If feasible, it will give a pristine signal if one can reach a density regime n 1/2 ~ 2n 0.