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Physical systems are characterized by inherent symmetries, one of which is encapsulated in theunits of their parameters and system states. These symmetries enable a lossless order-reduction, e.g.,via dimensional analysis based on the Buckingham theorem. Despite the latter's benefits, machinelearning (ML) strategies for the discovery of constitutive laws seldom subject experimental and/ornumerical data to dimensional analysis. We demonstrate the potential of dimensional analysis to significantlyenhance the interpretability and generalizability of ML-discovered secondary laws. Ournumerical experiments with creeping fluid flow past solid ellipsoids show how dimensional analysisenables both deep neural networks and sparse regression to reproduce old results, e.g., Stokes law fora sphere, and generate new ones, e.g., an expression for an ellipsoid misaligned with the flow direction.Our results suggest the need to incorporate other physics-based symmetries and invariancesinto ML-based techniques for equation discovery. 

In typical Engineering and Science education, students often are not given opportunities to build skills outside of narrowly defined, technical domains (Lucena 2013). Experiences that encourage students to engage in social justice and activist work is crowded out in traditional STEM programs. Oftentimes, these structures must be created deliberately in order to provide student leaders with this type of mentorship (Leydens 2014, Nieusma 2011). One such initiative, the Access Network, aims to do just that. The Access Network is a collection of programs (sites) that are situated in U.S. universities that work towards a more equitable, diverse, inclusive, and accessible version of the STEM community (Quan 2019). Access prioritizes student leaders, both at the network-level and in their local sites, by empowering them to take the lead on actions and by providing support for this work. Access sites engage in activities that build inclusive learning communities, provide guidance through peer mentorship, and support growth in students’ leadership around social justice. One major function of the Access Network is to connect students across these local efforts and to facilitate the sharing of ideas and experiences between sites. One central way that this is done is through the work of Network Fellows (NFs), student leaders who work collaboratively in network decision-making and team projects that support the network and the sites. The NF position provides space for students to take power over decision making and supports them through mentorship in social justice and activist approaches (Amezcua 2020). To better understand how students approach this role and view their work, we have conducted semi-structured interviews with nine Network Fellows who served in the role for at least two semesters. In our analysis of emergent themes, we have found that individual agency over their work, shared leadership in decision making, and building relationships across the network are key outcomes of the Network Fellow experience. We have additionally identified key conceptualizations of the team collaboration that Network Fellows discuss that cultivate the outcomes described above. We see these conceptualizations as important for capturing how the Network Fellow team conducts its work. We hope for our work to serve as a model for others that wish to cultivate similar experiences for their own students in STEM. 

The Living Physics Portal (the Portal), an online, open-source environment, was developed by a user-centered design process to support physics faculty in finding, sharing and adapting curricular materials for interdisciplinary college physics courses. Unlike other digital libraries, community-building activities are central to the design and functioning of the Portal, so users have opportunities to engage in discussions and collaborative development of resources. First, Portal design re-envisions college physics teaching as a collaborative and community-oriented endeavor. Second, the Portal design explicitly acknowledges physics faculty’s expertise in curriculum development. Third, Portal community activities and artifacts rely on users and participants to move forward with design, creating opportunities for physics faculty to substantially influence the future of the project. We report on details and purposes of the design, as well as empirical evaluation plans around its effectiveness. 

Sociologists and historians of science/engineering have documented the salience of meritocracy and technocracy in engineering and engineering education (Cech, 2014; Slaton, 2015; Riley, 2008). Some engineering education scholars have begun to document how technocracy and meritocracy have been mechanisms of marginalization within engineering education (Slaton, 2015; Foor, Walden, & Trytten, 2007; Secules, Gupta, Elby, & Turpen, 2018). Our team has been engaged in the iterative redesign of a pedagogy seminar for engineering peer educators working within a college-level introduction to engineering design course. Using tools of discourse analysis, we analyze how technocratic stances are reproduced or challenged in engineering peer educators’ talk during pedagogy seminar discussions. We study peer educators, in particular, because they are in a unique position to do harm if the ideologies of meritocracy and technocracy aren't challenged. Likewise, they are in a unique position to do good if they actively disrupt these ideologies in the introductory engineering design course. We present empirical examples of engineering peer educators both reproducing and contesting technocratic (and, at times, meritocratic) stances in reasoning about engineering education. We believe that such empirical examples can help engineering educators hone their attention to student thinking in the classroom and help us understand what it might look like to see evidence of growth in students’ reasoning. 

We report an improved measurement of the valence $u$and $d$quark distributions from the forward-backward asymmetry in the Drell-Yan process using $8.6{\mathrm{fb}}^{-1}$of data collected with the D0 detector in $p\overline{p}$collisions at $\sqrt{s}=1.96$. This analysis provides the values of new structure parameters that are directly related to the valence up and down quark distributions in the proton. In other experimental results measuring the quark content of the proton, $d$quark contributions are mixed with those from other quark flavors. In this measurement, the $u$and $d$quark contributions are separately extracted by applying a factorization of the QCD and electroweak portions of the forward-backward asymmetry. Published by the American Physical Society2024