The rotational dynamics of chemically similar systems based on freely jointed and freely rotating chains are studied. The second Legendre polynomial of vectors along chain backbones is used to investigate the rotational dynamics at different length scales. In a previous study, it was demonstrated that the additional bond-angle constraint in the freely rotating case noticeably perturbs the character of the translational relaxation away from that of the freely jointed system. Here, it is shown that differences are also apparent in the two systems' rotational dynamics. The relaxation of the end-to-end vector is found to display a long time, single-exponential tail and a stretched exponential region at intermediate times. The stretching exponents beta are found to be 0.75+/-0.02 for the freely jointed case and 0.68+/-0.02 for the freely rotating case. For both system types, time-packing-fraction superposition is seen to hold on the end-to-end length scale. In addition, for both systems, the rotational relaxation times are shown to be proportional to the translational relaxation times, demonstrating that the Debye-Stokes-Einstein law holds. The second Legendre polynomial of the bond vector is used to probe relaxation behavior at short length scales. For the freely rotating case, the end-to-end relaxation times scale differently than the bond relaxation times, implying that the behavior is non-Stokes-Einstein, and that time-packing-fraction superposition does not hold across length scales for this system. For the freely jointed case, end-to-end relaxation times do scale with bond relaxation times, and both Stokes-Einstein and time-packing-fraction-across-length-scales superposition are obeyed.

Despite no shortage of thoughtful analysis concerning how to more democratically develop and assess new technologies, practical progress toward democratized innovation has been paltry. This state of affairs suggests that the barriers to such democratic ends merit more attention. Building upon calls to more seriously examine citizens' understandings of technology as autonomous or deterministic, this paper characterizes the assumptions, beliefs, and patterns of thought undergirding technological determinism and permissionless innovation as technocratic governing mentalities. That is, they contribute to the biasing of political discourses, practices, and organizations toward non-decision making and adaptation with regards to technological change. Indeed, permissionless innovation is quickly becoming the motto of those aiming to legitimate a "hands-off" approach to the sociotechnical "disruptions" sought by Silicon Valley entrepreneurs. Moreover, this paper explores how STS, as both an academic and political endeavor, might better respond to the challenges these modes of thinking present. Drawing upon relevant work within social psychology and communications, several fruitful avenues for engaged research regarding undermining technocratic governing mentalities become apparent. Not only is there a pressing need for accessible and parsimonious counternarratives to technological determinism and permissionless innovation but also rhetorical strategies for making the democratization of technological appear continuous with aspects of status quo systems. Finally, given that technocratic governing mentalities are likely to have practical and material roots, inquiry should be directed toward understanding how different sociotechnical arrangements impact citizens' perception of the desirability and feasibility of democratizing technology.

Rotational relaxation functions of the end-to-end vector of short, freely jointed and freely rotating chains were determined from molecular dynamics simulations. The associated response functions were obtained from the one-sided Fourier transform of the relaxation functions. The Cole-Davidson function was used to fit the response functions with extensive use being made of Cole-Cole plots in the fitting procedure. For the systems studied, the Cole-Davidson function provided remarkably accurate fits [as compared to the transform of the Kohlrausch-Williams-Watts (KWW) function]. The only appreciable deviations from the simulation results were in the high frequency limit and were due to ballistic or free rotation effects. The accuracy of the Cole-Davidson function appears to be the result of the transition in the time domain from stretched exponential behavior at intermediate time to single exponential behavior at long time. Such a transition can be explained in terms of a distribution of relaxation times with a well-defined longest relaxation time. Since the Cole-Davidson distribution has a sharp cutoff in relaxation time (while the KWW function does not), it makes sense that the Cole-Davidson would provide a better frequency-domain description of the associated response function than the KWW function does.

This article argues that sustainable and communal neighborhoods could be significantly more common in North America if development practices addressed the barriers posed by sociotechnical obduracy and the inevitable limitations of expertise through expanded opportunities for experimentation. In reconceptualizing the problems faced by alternative urbanisms through the lens of science and technology studies, I explore how the intelligent trial-and-error (ITE) framework for governing emerging technologies could be extended to partially address the barriers of obduracy, uncertainty and complexity when pursuing alternative urban designs. An examination of how Baugruppen (cooperative building groups) were integrated into the planning process of Quartier Vauban, Freiburg, is used to illustrate both the potentials and a concrete application of an ITE-like approach. I then discuss some of the barriers to an ITE model of urban planning in North America and recommend further research at the intersection of urban studies and science and technology studies.

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