29th RQC Seminar
Dr. Marcello Dalmonte
(International Centre for Theoretical Physics (ICTP))
16:00-17:00 (JST), March 8, 2023 (Wednesday)
Hybrid (Zoom / Wako Welfare and Conf. 2F Large Meeting Room RIKEN Wako branch)
Data mining the output of quantum simulators - from critical behavior to algorithmic complexity
Recent experiments with quantum simulators and noisy intermediate-scale quantum devices have demonstrated unparalleled capabilities of probing many-body wave functions, via directly probing them at the single quantum level via projective measurements. However, very little is known about to interpret and analyse such huge datasets.
In this talk, I will show how it is possible to provide such characterisation of many-body quantum hardware via a direct and assumption-free data mining. The core idea of this programme is the fact that the output of quantum simualtors and computers can be construed as a very high-dimensional manifold. Such manifold can be characterised via basic topological concepts, in particular, by their intrinsic dimension. Exploiting state of the art tools in non-parametric learning, I will discuss theoretical results for both classical and quantum many-body spin systems that illustrate how data structures undergo structural transitions whenever the underlying physical system does, and display universal (critical) behavior in both classical and quantum mechanical cases.
I will the discuss two concrete applications of these techniques to quantum matter experiments: State preparation protocols in Rydberg atom platform, and universal dynamics in out-of-equilibrium Bose-Einstein condensates. In both cases, I will show how tracking complexity provides novel insights onto the working of such systems, in particular, on their critical behavior. Moreover, direct application of network theory will be utilized to validate the working of the quantum simulator, and to determine - in an assumption-free manner - what the relevant degrees of freedom are.