We investigate the gravitational Poissonian spontaneous localization (GPSL) model, a hybrid classical-quantum model in which classical Newtonian gravity emerges from stochastic collapses of the mass density operator, and consistently couples to quantum matter. Unlike models based on continuous weak measurement schemes, we show that GPSL ensures vacuum stability; this, together with its applicability to identical particles and fields, makes it a promising candidate for a relativistic generalization. We analyze the model’s general properties, and compare its predictions with those based on continuous weak measurement schemes. Notably, here the gravitational feedback enters entirely through the non-Hermitian jump operators, without modifying the unitary part of the dynamics. We show that this leads to a short-range gravitational back-reaction and permits decoherence rates below those of any model based on continuous weak measurement schemes. We provide explicit examples, including the dynamics of a single particle and a rigid sphere, to illustrate the distinctive phenomenology of the model. Finally, we discuss the experimental testability of GPSL, highlighting both interferometric and non-interferometric strategies to constrain its parameters and distinguish it from competing models.

中文翻译：

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具有稳定真空的混合经典量子牛顿引力

我们研究了引力泊松自发定位 （GPSL） 模型，这是一种经典量子混合模型，其中经典牛顿引力从质量密度算子的随机坍缩中出现，并始终与量子物质耦合。与基于连续弱测量方案的模型不同，我们表明 GPSL 确保了真空稳定性;这，加上它对相同粒子和场的适用性，使其成为相对论概括的有希望的候选者。我们分析了模型的一般特性，并将其预测与基于连续弱测量方案的预测进行了比较。值得注意的是，这里的引力反馈完全通过非厄米特跳跃算子进入，而不修改动力学的酉部分。我们表明，这会导致短程引力反反应，并允许退相干率低于基于连续弱测量方案的任何模型。我们提供了明确的示例，包括单个粒子和刚性球体的动力学，以说明模型的独特现象学。最后，我们讨论了 GPSL 的实验可测试性，重点介绍了干涉和非干涉策略，以约束其参数并将其与竞争模型区分开来。