TY - JOUR

T1 - Stability of φ4 -vector model: Four-loop ε expansion study

AU - Adzhemyan, L. Ts.

AU - Kudlis, A.

PY - 2023/2/24

Y1 - 2023/2/24

N2 - In most papers, ϕ4-field theory with the vector (d-component) field ϕα is considered as a particular case of the n-component field model for n = d and O(n) symmetry. However, in such a model the symmetry O(d) admits an addition to the action of a term proportional to the squared divergence of the field ∼h(∂αϕα ) 2. From the point of view of renormalization group analysis, it requires a separate consideration, because it may well change the nature of the critical behavior of the system. Therefore, this frequently neglected term in the action requires a detailed and accurate study on the issue of the existence of new fixed points and their stability. It is known that within the lower order of perturbation theory the only infrared stable fixed point with h = 0 exists but the corresponding positive value of stability exponent ωh is tiny. This led us to analyze this constant in higher orders of perturbation theory by calculating the four-loop renormalization group contributions for ωh in d = 4 − 2ε within the minimal subtraction scheme, which should be enough to infer positivity or negativity of this exponent. The value turned out to be undoubtedly positive, although still small even in higher loops: 0.0156(3). These results cause the corresponding term to be neglected in the action when analyzing the critical behavior of the O(n)-symmetric model. At the same time, the small value of ωh shows that the corresponding corrections to the critical scaling are significant in a wide range.

AB - In most papers, ϕ4-field theory with the vector (d-component) field ϕα is considered as a particular case of the n-component field model for n = d and O(n) symmetry. However, in such a model the symmetry O(d) admits an addition to the action of a term proportional to the squared divergence of the field ∼h(∂αϕα ) 2. From the point of view of renormalization group analysis, it requires a separate consideration, because it may well change the nature of the critical behavior of the system. Therefore, this frequently neglected term in the action requires a detailed and accurate study on the issue of the existence of new fixed points and their stability. It is known that within the lower order of perturbation theory the only infrared stable fixed point with h = 0 exists but the corresponding positive value of stability exponent ωh is tiny. This led us to analyze this constant in higher orders of perturbation theory by calculating the four-loop renormalization group contributions for ωh in d = 4 − 2ε within the minimal subtraction scheme, which should be enough to infer positivity or negativity of this exponent. The value turned out to be undoubtedly positive, although still small even in higher loops: 0.0156(3). These results cause the corresponding term to be neglected in the action when analyzing the critical behavior of the O(n)-symmetric model. At the same time, the small value of ωh shows that the corresponding corrections to the critical scaling are significant in a wide range.

UR - https://www.mendeley.com/catalogue/fe44ad16-9568-3f51-84b4-477d274e2c68/

U2 - DOI: 10.1103/PhysRevE.107.024133

DO - DOI: 10.1103/PhysRevE.107.024133

M3 - Article

VL - 107

JO - Physical Review E

JF - Physical Review E

SN - 1539-3755

IS - 2

M1 - 024133

ER -