Makoto Hiramoto

New Vacuum of Bethe Ansatz Solutions in Thirring Model

We find a new vacuum of the Bethe ansatz solutions in the massless Thirring model. This vacuum breaks the chiral symmetry and has the lower energy than the well-known symmetric vacuum energy. Further, we evaluate the energy spectrum of the one particle–one hole (1 p –1 h ) states, and find that it has a finite gap. The analytical expressions for the true vacuum as well as for the lowest 1 p –1 h excited state are also found. Further, we examine the bosonization of the massless Thirring model and prove that the well-known procedure of bosonization of the massless Thirring model is incomplete because of the lack of the zero mode in the boson field.

Bound state spectrum of the massive Thirring model in a rest frame

The bound state spectrum of the massive Thirring model is studied in the framework of the canonical quantization in the rest frame. First, we quantize the field with the massless free fermion basis states. Then, we make a Bogoliubov transformation. This leads to the natural mass renormalization. The bound state spectrum is analytically solved by the

Non-equivalence between Heisenberg XXZ spin chain and Thirring model

q\overline{q}

EDM Operator Free from Schiff's Theorem

Fock space. It is found that the spectrum has the right behavior both for the weak and for the strong coupling limits after the appropriate wave function regularization. This regularization is quite clear and the treatment is self-consistent for the bound state problem compared to other regularizations. Further, we show that the interaction between

Violation of S -matrix factorization in the massive Thirring model

q\overline{q}

G FACTOR OF A TIGHTLY BOUND ELECTRON

bosons is always repulsive and therefore there is no bound state in the four fermion

No massless boson in chiral symmetry breaking in NJL and Thirring models

(qq\overline{q}\overline{q})

New spectrum and condensate in two dimensional QCD

Fock space. This confirms that there is only one bound state in the massive Thirring model.

No Goldstone boson in NJL and Thirring models

Abstract.The Bethe ansatz equations for the spin 1/2 Heisenberg XXZ spin chain are numerically solved, and the energy eigenvalues are determined for the antiferromagnetic case. We examine the relation between the XXZ spin chain and the massless Thirring model, and show that the spectrum of the XXZ spin chain has a gapless excitation while the regularized Thirring model calculated with the Bogoliubov transformation method has a finite gap. This finite gap spectrum is also confirmed by the Bethe ansatz solution of the massless Thirring model.

Foldy-Wouthuysen transformed EDM operator in atomic system

We present a generalization of Schiff’s transformation of electric dipole moments (EDM) in quantum field theory. Under the unitary transformation, the time and parity violating interaction i ge 2 ¯ ψσµνγ5ψF µν is transformed into a new form, but its nonrelativistic reduction has a unique form to which Schiff’s theorem does not apply. The relativistic corrections to the new EDM operator slightly increase the EDM, as given by b2(αZ) 2 with b2 2. It is thus seen that the calculation of the EDM with nonrelativistic Hartree-Fock wave functions presents a conservative but reliable estimation for the enhancement factor of the EDM in atoms.