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Noise in existing quantum processors only enables an approximation to ideal quantum computation. However, these approximations can be vastly improved by error mitigation, for the computation of expectation values, as shown by small-scale experimental demonstrations. However, the practical scaling of these methods to larger system sizes remains unknown. Here, we demonstrate the utility of zero-noise extrapolation for relevant quantum circuits using up to 26 qubits, circuit depths of 60, and 1080 CNOT gates. We study the scaling of the method for canonical examples of product states and entangling Clifford circuits of increasing size, and extend it to the quench dynamics of 2-D Ising spin lattices with varying couplings. We show that the efficacy of the error mitigation is greatly enhanced by additional error suppression techniques and native gate decomposition that reduce the circuit time. By combining these methods, we demonstrate an accuracy in the approximate quantum simulation of the quench dynamics that surpasses the classical approximations obtained from a state-of-the-art 2-D tensor network method. These results reveal a path to a relevant quantum advantage with noisy, digital, quantum processors., 7 pages, 3 figures

The management of locally advanced muscle invasive bladder cancer (MIBC) often necessitates neo-adjuvant chemotherapy (NAC) to eliminate any micro-metastatic disease prior to definitive radical cystectomy (RC) and pelvic lymph node dissection (PLND). The most common imaging techniques traditionally used during this process are computerised tomography (CT) and magnetic resonance imaging (MRI), both of which lack a high sensitivity for nodal staging. In this paper, we attempt to review the evolving indications of F-fluoro-2-deoxy-D-glucose positron emission tomography/computerised tomography (FDG-PET/CT) imaging, in the pre-clinical and post-treatment staging of bladder cancer, with a focus on its ability to evaluate response to NAC. We concluded that use of FDG-PET/CT allows for improved nodal staging and metastatic disease detection, compared to traditional imaging modalities. This enabled earlier detection of tumour response to NAC and/or residual disease, impacting factors such as duration of chemotherapy, with its associated adverse effects, and timing of surgical intervention. However, further studies are required to reliably assess its impact on both overall and disease-free survival.