Nucleon Electric Polarizability in Soliton Models and the Role of the Seagull Terms
نویسندگان
چکیده
The full Hamiltonian of the soliton models contains no electric seagull terms. Here it is shown that if one restricts the fields to the collective subspace then electric seagull terms are induced in the effective Hamiltonian. These effective seagull contributions are consistent with gauge invariance. They also reproduce the leading nonanalytic behavior of a large Nc chiral perturbation theory calculation of the electric polarizability. Fellow of the CONICET, Buenos Aires, Argentina. On leave from Department of Physics, University of Maryland, College Park, MD 20742.
منابع مشابه
Do really the seagull terms survive for the electric polarizability of the nucleon ?
The seagull terms for the electric polarizability of the nucleon are shown to vanish indeed, if one introduces fluctuations around the Skyrmion configuration, and after all the origin of the electric polarizability cannot be attributed to the seagull terms in the Skyrme model. E-mail address [email protected] E-mail address ueharam@cc. saga-u.ac.jp 1
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