The feature of the low-lying spectrum and a complete set of quantum numbersof the (e+e+e-e-) system have been deduced based on symmetry consideration. Theexistence of a low odd-parity L=1 excited state with the spins of the twoelectrons coupled to s1=1 and the two positrons coupled to s2=0 (or s1=0 ands2=1) and a low even-parity L=0 excited state with s1=s2=1 have been predicted.The discussion is generalized to 2-dimensional (e+e+e-e-) systems.
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