Author Contributions † A. Natarajan and J. Xie contributed equally to this work. ' ACKNOWLEDGMENTH. Zeng thanks the support of an NSERC Discovery Grant Award. The authors acknowledge the NSERC Industrial Research Chair Program in Oil Sands Engineering for the support of the study. Thanks are due to Syncrude Canada Ltd. for providing the bitumen samples. The SFA and AFM used in this study were purchased under CFI funds which are greatly appreciated.

We show that the class MIP * of languages that can be decided by a classical verifier interacting with multiple all-powerful quantum provers sharing entanglement is equal to the class RE of recursively enumerable languages. Our proof builds upon the quantum low-degree test of (Natarajan and Vidick, FOCS 2018) by integrating recent developments from (Natarajan and Wright, FOCS 2019) and combining them with the recursive compression framework of (Fitzsimons et al., STOC 2019).An immediate byproduct of our result is that there is an efficient reduction from the Halting Problem to the problem of deciding whether a two-player nonlocal game has entangled value 1 or at most 1 2 . Using a known connection, undecidability of the entangled value implies a negative answer to Tsirelson's problem: we show, by providing an explicit example, that the closure C qa of the set of quantum tensor product correlations is strictly included in the set C qc of quantum commuting correlations. Following work of (Fritz, Rev. Math. Phys. 2012) and (Junge et al., J. Math. Phys. 2011) our results provide a refutation of Connes' embedding conjecture from the theory of von Neumann algebras.

The adsorption process of asphaltene onto molecularly smooth mica surfaces from toluene solutions of various concentrations (0.01 -1 wt%) was studied using a Surface Forces Apparatus (SFA). Adsorption of asphaltenes onto mica was found to be highly dependent on adsorption time and concentration of the solution. The adsorption of asphaltenes led to an attractive bridging force between the mica surfaces. The adsorption process was identified to be controlled by diffusion of asphaltenes from the bulk solution to the mica surface with a diffusion coefficient on the order of 10 -10 m 2 /s at room temperature, depending on asphaltene bulk concentration. This diffusion coefficient corresponds to a hydrodynamic molecular radius of approximately 0.5 nm, indicating that asphaltene diffuses to mica surfaces as individual molecules at very low concentration (e.g. 0.01 wt%). Atomic force microscopy (AFM) images of the adsorbed asphaltenes on mica support the results of the SFA force measurements. The results from the SFA force measurements provide an insight on the molecular interactions (e.g. steric interaction, bridging attraction as a function of distance) of asphaltenes in organic media and hence their roles in crude oil and bitumen production.

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We define and demonstrate a procedure for carrying out wind turbine load validation based on measurements from nacelle‐mounted scanning lidars. Two coherent Doppler lidar systems, a pulsed lidar and a continuous‐wave lidar, are mounted on a 2.3‐MW wind turbine equipped with load measurement sensors. Wind measurements from a meteorological mast mounted at 2.5 rotor diameters distance are used as reference. The study shows how lidar measurements are processed and applied as inputs to aeroelastic load simulations, and the results are then compared with simulations where the wind inputs have been determined using the meteorological mast data in compliance with the IEC61400‐13 standard. For the majority of simulation cases considered, the use of nacelle‐mounted lidar measurements results in load estimation uncertainties lower or equal to those that are based on measurements from cup anemometers on the mast. These results demonstrate the usefulness of nacelle‐mounted lidars as tools for carrying out load validation without the need of meteorological masts.