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Abstract

Gauge theories are the governing principles of elementary interactions between matter particles and the mediating gauge fields. Even though they have been studied extensively in the realm of High Energy Physics (HEP), realizing their quantum dynamical aspects still remains an arduous task. Quantum simulators provide a promising approach in this regard by mimicking such systems, and mapping them onto other physical platforms that are exper- imentally accessible. In this thesis, an extension of the experimental studies undertaken to simulate a minimalistic version U(1) of Lattice Gauge Theory (LGT), also known as Schwinger model is presented [1]. The experiment conducted therein used an ultracold gas mixture of sodium (23Na) and lithium (7Li), where 23Na realized the gauge field and 7Li realized the mat- ter component. The principle of local gauge invariance, which is a consequence of matter gauge coupling was realized through interspecies spin changing collisions (SCC). A theoreti- cal framework based on mean field approach was then used to describe the corresponding ex- perimental data. As the data was acquired over multiple realizations, it exhibited fluctuations, which were unaccounted for in the previous description of the model. This thesis provides an account of data analysis and theoretical treatments that were performed in order to investigate the cause of such fluctuations. Along with a better understanding of the underlying dynamics, this study opens up further insights. For instance, the fluctuations arising from finite tempera- ture of the atoms might reveal the long time behavior of the system. Furthermore, fluctuations of technical origin are critical in assessing the stability of an experimental setup, which when reduced, pave the way to the study of quantum fluctuations, the role of which is pivotal in all the areas of fundamental physics.