The nucleon form-factors of the energy–momentum tensor in the Skyrme model

Abstract

The nucleon form factors of the energy-momentum tensor are studied in the large-Nc limit in the framework of the Skyrme model.

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“…Hereby the perhaps most important point concerns the stability of the studied solution. The von Laue condition (14) provides a useful global criterion, which was shown to be satisfied in various approaches including nuclei, nucleons, pions, Skyrmions, Q-balls where the solutions were absolutely stable [9,10,[25][26][27][28][29]. But also meta-stable and unstable solutions satisfy the von Laue condition [29][30][31] which means it is a necessary but not sufficient condition for stability.…”

“…We checked that the condition (18) is satisfied in all systems we are aware of where EMT densities were studied [9,10,[25][26][27][28][29][30][31]. As this includes unstable systems, apparently also (18) is a necessary but not sufficient condition for stability.…”

“…Indeed, in all systems studied so far the D-terms were found to be negative [9,10,[25][26][27][28][29][30][31]. It would be natural to expect that the criteria (17,18) hold also in quantum field theory, although in this case more care is needed.…”

“…Soliton models are particularly convenient for that [9,10]. In the chiral limit in leading order of the large-N c expansion the densities behave as, see App.…”

“…For that in [8] results were used from the chiral quark soliton model [9]. In this work, we will use of a different model for EMT densities, namely the Skyrme model [10]. This model is based on chiral symmetry and the 1/N c expansion like the chiral quark soliton model.…”