Perspectives in 2022

Even for flows as simple as those through pipes and channels, the nature of the transition to turbulence has remained elusive. This Perspective discusses how statistical mechanics and specifically directed percolation may provide an answer to this old problem.

For many complex or living systems, it is impossible to individually sample all their units, but subsampling can heavily bias the inference about their collective properties. This Perspective presents the subsampling problem and reviews recent developments to overcome this fundamental limitation.

Scientific understanding is one of the main aims of science. This Perspective discusses how advanced computational systems, and artificial intelligence in particular, can contribute to driving scientific understanding.

In this Perspective on the physics of particle generation in the respiratory tract, fate in the air upon exhalation and the physics of inhalation, the authors conclude that the general understanding of the entire process is rudimentary, and many open questions remain.

Topological quantum materials host protected, high-mobility surface states which can be used for energy conversion and storage. This Perspective discusses recent progress in using topological materials for water splitting, batteries and supercapacitors.

The standard Hamiltonian approach to quantum field theory violates Poincaré invariance, leading to predictions with artificial dynamical effects and potentially obscuring the fundamental description of a physical system. This Perspective explains how such issues are avoided by using light-front Hamiltonian quantization.

Finding the most appropriate machine learning algorithm for the analysis of any given scientific dataset is currently challenging, but new machine learning benchmarks for science are being developed to help.