Journal of Experimental and Theoretical Physics

, Volume 127, Issue 5, pp 851–859 | Cite as

Superfluid Liquid Crystals: Pasta Phases in Neutron Star Crusts

  • D. N. KobyakovEmail author
  • C. J. PethickEmail author


The pasta phases predicted to occur near the inner boundary of the crust of a neutron star resemble liquid crystals, a smectic A in the case of sheet-like nuclei (lasagna) and the columnar phase in the case of rod-like nuclei (spaghetti). An important difference compared with usual liquid crystals is that the nucleons are superfluid. We develop the hydrodynamic equations for this system and use them to study collective oscillations. Nucleon superfluidity leads to important qualitative differences in the spectra of these oscillations and also increases their frequencies compared with ordinary liquid crystals. We discuss a number of directions for future work.



We are grateful to Gerd Schroder-Turk for informative discussions and Lev Pitaevskii for valuable correspondence. This work was supported by the Russian Foundation for Basic Research, according to the research project no. 31 16-32-60023 mol_a_dk.


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Copyright information

© Pleiades Publishing, Inc. 2018

Authors and Affiliations

  1. 1.Institute of Applied Physics, Russian Academy of SciencesNizhny NovgorodRussia
  2. 2.The Niels Bohr International Academy, The Niels Bohr Institute, University of CopenhagenCopenhagen ØDenmark
  3. 3.NORDITA, KTH Royal Institute of Technology and Stockholm UniversityStockholmSweden

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