Citation bias and gendered citation practices in contemporary physics

The under-attribution and historical erasure of women's contributions to scientific scholarship is well-known and well-studied. These effects are still felt today in myriad ways by women scientists, including lower interest in collaboration, lower perception of academic excellence, lower than expected award reception, and fewer invited paper commissions. Yet another crucial metric of under-attribution within scientific scholarship is the under-citation of papers authored by women relative to expected rates, and the corresponding over-citation of papers authored by men. This "gap" in citations has been quantified in several fields ranging from international relations, to neuroscience, to communications, to astronomy. Here, we quantify the citation gap in contemporary physics, analyzing over one million articles published over the last 25 years in 35 physics journals that span a wide range of subfields. We investigate correlations between this gap and the dimensions of citation venue, citation type, and citers themselves, demonstrating that citation statistics are not a homogeneous background effect baked into the fabric of physics scholarship, but rather vary widely according to these metrics. Thus, we demonstrate that although citation behavior is a personal action, it adheres to certain trends at the population level, and has wide-ranging and potentially harmful effects. We then discuss possible strategies for citation bias mitigation.