Detecting flavor content of the vacuum using the Dirac operator spectrum

(χQCD Collaboration) Guangdong Provincial Key Laboratory of Nuclear Science, Institute of Quantum Matter, South China Normal University, Guangzhou 510006, China Guangdong-Hong Kong Joint Laboratory of Quantum Matter, Southern Nuclear Science Computing Center, South China Normal University, Guangzhou 510006, China Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506, USA Department of Physics, The George Washington University, Washington, DC 20052, USA Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China International Centre for Theoretical Physics Asia-Pacific, Beijing/Hangzhou, China