Department of Physics, The Catholic University of Korea, Bucheon 14662, Republic of Korea.
Phys Rev E. 2017 Sep;96(3-1):032113. doi: 10.1103/PhysRevE.96.032113. Epub 2017 Sep 11.
The one-dimensional pair contact process with diffusion (PCPD), an interacting particle system with diffusion, pair annihilation, and creation by pairs, has defied consensus about the universality class to which it belongs. An argument by Hinrichsen [Physica A 361, 457 (2006)PHYADX0378-437110.1016/j.physa.2005.06.101] claims that freely diffusing particles in the PCPD should play the same role as frozen particles when it comes to the critical behavior. Therefore, the PCPD is claimed to have the same critical phenomena as a model with infinitely many absorbing states that belongs to the directed percolation (DP) universality class. To investigate if diffusing particles are really indistinguishable from frozen particles in the sense of the renormalization group, we study numerically a variation of the PCPD by introducing a nonorder field associated with infinitely many absorbing states. We find that a crossover from the PCPD to DP occurs due to the nonorder field. By studying a similar model, we exclude the possibility that the mere introduction of a nonorder field to one model can entail a nontrivial crossover to another model in the same universality class, thus we attribute the observed crossover to the difference of the universality class of the PCPD from the DP class.
一维对接触扩散过程（PCPD）是一个具有扩散、对消和对生成的相互作用粒子系统，它挑战了人们对其所属普适类的共识。Hinrichsen 的一个论点[Physica A 361, 457 (2006)PHYADX0378-437110.1016/j.physa.2005.06.101]声称，在临界行为方面，PCPD 中的自由扩散粒子应该与冻结粒子扮演相同的角色。因此，PCPD 被认为具有与属于定向渗流（DP）普适类的具有无限多个吸收态的模型相同的临界现象。为了研究扩散粒子在重整化群意义上是否真的与冻结粒子不可区分，我们通过引入与无限多个吸收态相关的非有序场来数值研究 PCPD 的变化。我们发现，由于非有序场的存在，PCPD 到 DP 发生了交叉。通过研究类似的模型，我们排除了仅仅向一个模型引入非有序场就会导致另一个具有相同普适类的模型发生非平凡交叉的可能性，因此我们将观察到的交叉归因于 PCPD 普适类与 DP 类的差异。
