Martín Mayor, VíctorYllanes, D.2023-06-202023-06-202009-07-021539-375510.1103/PhysRevE.80.015701https://hdl.handle.net/20.500.14352/42769© 2009 American Physical Society. We thank L. A. Fernandez for discussions. We were partly supported by MEC Spain through Contract No. FIS2006- 08533. The bulk of our computations were carried out at BIFI.We propose a cluster simulation algorithm for statistical ensembles with fixed order parameter. We use the tethered ensemble, which features Helmholtz’s effective potential rather than Gibbs’s free energy and in which canonical averages are recovered with arbitrary accuracy. For the D=2,3 Ising model our method’s critical slowing down is comparable to that of canonical cluster algorithms. Yet, we can do more than merely reproduce canonical values. As an example, we obtain a competitive value for the 3D Ising anomalous dimension from the maxima of the effective potential.engjournal articlehttp://dx.doi.org/10.1103/PhysRevE.80.015701https://journals.aps.orgopen access533-dimensional ising-modelCritical-dynamicsEvaporation/condensation transitionSpinodal decompositionEquilibrium dropletsLaws.Física-Modelos matemáticos