This study investigates the anomalous cooling of bosons when transitioning from three-dimensional (3D) to two-dimensional (2D) or one-dimensional (1D) systems. Cold atomic gases provide an ideal platform for studying strongly interacting quantum systems, as they allow precise control over parameters like interaction strength and confinement. The researchers implemented high-sensitivity thermometry in the nanokelvin range for 2D and 1D Bose gases, using the temperature dependence of the first-order correlation function. They found that reducing the dimensionality can lead to substantial temperature changes, with the 1D case showing a significant drop in temperature compared to the initial 3D temperature. This anomalous cooling is attributed to the interplay of dimensional reduction and strong interactions, with the 1D system exhibiting lower temperatures due to the reduction in accessible configurations and the fermionization of bosons. The findings are supported by quantum Monte Carlo simulations and an entropy argument, showing that the system's entropy changes with dimensionality, leading to cooling at low temperatures. The study highlights the importance of temperature control in quantum simulations and provides insights into the behavior of strongly interacting quantum systems in different dimensions. The results demonstrate that dimensional reduction does not always lead to heating, as previously observed, and offer a new understanding of the cooling mechanisms in low-dimensional quantum systems.This study investigates the anomalous cooling of bosons when transitioning from three-dimensional (3D) to two-dimensional (2D) or one-dimensional (1D) systems. Cold atomic gases provide an ideal platform for studying strongly interacting quantum systems, as they allow precise control over parameters like interaction strength and confinement. The researchers implemented high-sensitivity thermometry in the nanokelvin range for 2D and 1D Bose gases, using the temperature dependence of the first-order correlation function. They found that reducing the dimensionality can lead to substantial temperature changes, with the 1D case showing a significant drop in temperature compared to the initial 3D temperature. This anomalous cooling is attributed to the interplay of dimensional reduction and strong interactions, with the 1D system exhibiting lower temperatures due to the reduction in accessible configurations and the fermionization of bosons. The findings are supported by quantum Monte Carlo simulations and an entropy argument, showing that the system's entropy changes with dimensionality, leading to cooling at low temperatures. The study highlights the importance of temperature control in quantum simulations and provides insights into the behavior of strongly interacting quantum systems in different dimensions. The results demonstrate that dimensional reduction does not always lead to heating, as previously observed, and offer a new understanding of the cooling mechanisms in low-dimensional quantum systems.