Many-Body Theory

BI Si-wen

The tiny disturbing theory of quantum human body was studied in this paper surrounding microcosmic field of digital human body. The contents are the non-brief-combination state tiny disturbing theory of quantum human body; the tiny disturbing theory under brief-combination case of quantum human body; the calculus of variations of quantum human body; the tiny disturbing theory of quantum human body related to time; the transition probability of quantum human body; the light emission and absorption of quantum human body and the selection rule of quantum human body. It provided a theoretical basis and experimental gist for microcosmic study of digital human body.

Ryogo Kubo

Aditi Sen, Ujjwal Sen

The mean-field theory, in its different hues, forms a useful tool for investigating single-body properties, like magnetization and susceptibility, of many-body systems. We propose an "entanglement mean-field theory", which transforms a many-body system into a two-body one, while retaining footprints of the many-body parent, using which it is possible to examine its two-body properties, and predict temperature-driven as well as quantum fluctuation-driven critical phenomena, by considering two-body self-consistency equations in contrast to single-body ones in mean-field–like theories. Compared to mean-field theory, the proposed one, with little to no extra complicacy, makes better predictions for the critical points, as well as for the qualitative and quantitative behavior of single- and two-body physical quantities. In particular, the predictions of the proposed theory are in much better conformity with the Curie-Weiss law for magnetization. Also, the proposed theory predicts an order by disorder for a correlation function in the random-field transverse quantum Ising model.

Y. B. Band, Y. Avishai

BI Si-wen

Scattering theoretical model is the main content of the study of quantum human body information mechanism. The interaction idea of quantum human body, the functor of quantum human body state evolving with time and the outspread of tiny disturbing theory of quantum human body were discussed in this paper. The scattering matrix of quantum human body, the outspread of tiny disturbing theory of quantum human body S matrix, the scattering section of quantum human body and the disparting wave method of quantum human body were expounded. Finally, the author summarized from seven aspects to the whole paper. Theoretical models were provided for the study of scattering mechanism of quantum human body.