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arXiv · 2307.13276

Force on a moving object in an ideal quantum gas

Wittaya Kanchanapusakit·Pattarapon Tanalikhit
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Abstract

We consider a heavy external object moving in an ideal gas of light particles. Collisions with the gas particles transfer momentum to the object, leading to a force that is proportional to the object's velocity but in the opposite direction. In an ideal classical gas at temperature $T$, the force acting on the object is proportional to $\sqrt{T}$. Quantum statistics causes a deviation from the $\sqrt{T}$-dependence and shows that the force scales with $T^2$ at low temperatures. At $T=0$, the force vanishes in a Bose gas but is finite in a Fermi gas.

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Wittaya Kanchanapusakit, Pattarapon Tanalikhit. 2023-07-25. Force on a moving object in an ideal quantum gas. https://doi.org/10.1119/5.0127334

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