Accurate critical exponents from the ε-expansion

Accurate critical exponents from the -expansion

Critical exponents and the pseudo-ǫ expansion

We present the pseudo-ǫ expansions (τ -series) for the critical exponents of a λφ4 threedimensional O(n)-symmetric model obtained on the basis of six-loop renormalization-group expansions. Concrete numerical results are presented for physically interesting cases n = 1, n = 2, n = 3 and n = 0, as well as for 4 ≤ n ≤ 32 in order to clarify the general properties of the obtained series. The pseudo...

Critical Exponents without the Epsilon Expansion

We argue that the sharp-cuto Wilson renormalization group provides a powerful tool for the analysis of second-order and weakly rst-order phase transitions. In particular, in a computation no harder than the calculation of the 1-loop e ective potential, we show that the Wilson RG yields the xed point couplings and critical exponents of 3-dimensional O(N) scalar eld theory, with results close to ...

Critical exponents from five-loop strong-coupling φ4-theory in 4 − ε dimensions

Recently, one of us [1, 2] has developed a new approach to critical exponents of field theories based on the strong-coupling limit of variational perturbation expansions [3] and [4]3. This limit is relevant for critical phenomena if the renormalization constants are expressed in terms of the unrenormalized coupling constant. The theory was first applied successfully to O(N)symmetric φ4-theories...

Critical Exponents from the Effective Average Action

We compute the critical behaviour of three-dimensional scalar theories using a new exact non-perturbative evolution equation. Our values for the critical exponents agree well with previous precision estimates.