In TAO https://tarxiv.org/tao Volume 2021 https://tarxiv.org/tao.2021 Issue 09 https://tarxiv.org/tao.2021‑09
Abstract
The physics of photon momentum are straightforward mathematically but can produce surprisingly counterintuitive outcomes. A few simple calculations show how a single photon of green light can, in principle, impart two locomotive engines’ worth of momentum without violating energy conservation. The calculation is one example of why quantum mechanics needs better accounting of linear momentum.