In this issue: February 2022.

Velocity reciprocity and the relativity principle Patrick Moylan B 90 b (2), p. 126 https://doi.org/10.1119/10.0009219 Velocity reciprocity is the property that pairs of inertial reference frames will measure each other to have equal and opposite relative velocities. This paper analyses the group-theoretic foundations of relativity theory to explore what additional assumptions must be made for velocity reciprocity to hold, and also explores the misconception that velocity reciprocity follows from the relativity of motion principle. Exploring complex pattern formation with convolutional neural networks Christian Scholz and Sandy Scholz B 90 b (2), p. 141 https://doi.org/10.1119/5.0065458 Machine learning is becoming more and more important in the analysis of data in many fields including physics. [Extracted from the article]