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1. Stokes waves are unstable, even very small ones

   https://doi.org/10.4171/EMSS/90  

   Creedon, Ryan P; Nguyen, Huy Q; Strauss, Walter A (May 2025, EMS Surveys in Mathematical Sciences)

   WS: it is difficult to write about Thomas Kappeler in the past tense. He was a brilliant mathematician, but more importantly he was a wonderfully open, generous, and friendly person. I was fortunate that we had many opportunities to spend time together and discuss mathematics. I greatly miss him.A Stokes wave is a traveling free-surface periodic water wave that is constant in the direction transverse to the direction of propagation. Even Stokes waves of very small amplitude are unstable when subjected to various perturbations. We present a brief survey of this phenomenon with emphasis on transverse perturbations. 

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2. Scattering of EM waves from a Rotating Dispersive Very Good Conducting Cylinder

   https://doi.org/10.1109/WiSEE.2019.8920366  

   Abuhduma, Esmail M; Comert, Gurcan; Elqaouaq, Ahmed; Reeves, Ashleigh; Kellen, Williams (October 2019, 2019 IEEE International Conference on Wireless for Space and Extreme Environments (WiSEE))

   This research focuses on studying the scattering phenomenon. Scattering electromagnetic waves from a rotating conducting cylinder is investigated when the material of the conducting cylinder is linear, homogeneous, isotropic, and dispersive. This study is an extension of a previous work that investigated the effect of the rotating conducting cylinder on the scattered phase and amplitude, when the material of the conducting cylinder is linear, homogeneous, isotropic, and nondispersive. One of the important result of the previous work is that the Franklin transformation is a proper and more accurate method to calculate the effect of the rotation, and gives more accurate results than Galilean transformation. In this research, the Franklin transformation will be used to investigate the effect of the rotation of the object on the scattered phase and magnitude of the incident waves. The two types of incident waves (E-wave and H-wave) will be considered herein. The simulation results will clearly display the behavior of the scattered phase and magnitude with changes to the incident frequency, the speed of rotation, and the radius of the very good conducting cylinder. Moreover, this result is compared with the result of the previous work (non- dispersive material) to show the behavior of the scattered phase and magnitude when the incident frequency, speed of the rotation and radius of the very good conducting cylinder is changed. 

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3. The low period atmospheric gravity waves observed using Very Low Frequency signals

   https://doi.org/10.23919/URSIAP-RASC.2019.8738659  

   Maurya, Ajeet K.; Cohen, Morris B.; Kumar, K. Niranjan; Phanikumar, D. V.; Singh, Rajesh (March 2019, URSI RASC)
4. Waves and Turbulence in the Very Local Interstellar Medium: From Macroscales to Microscales

   https://doi.org/10.3847/1538-4357/abc88a  

   Fraternale, Federico; Pogorelov, Nikolai V. (January 2021, The Astrophysical Journal)

   null (Ed.)
5. Bursty Energetic Electron Precipitation by High‐Order Resonance With Very‐Oblique Whistler‐Mode Waves

   https://doi.org/10.1029/2022GL101920  

   Gan, Longzhi; Artemyev, Anton; Li, Wen; Zhang, Xiao‐Jia; Ma, Qianli; Mourenas, Didier; Angelopoulos, Vassilis; Tsai, Ethan; Wilkins, Colin (April 2023, Geophysical Research Letters)

   Abstract Resonant interactions with whistler‐mode waves are one of the most important drivers for rapid energetic electron precipitation. In this letter, we study a conjunction event, where bursts of energetic electron precipitation (50–800 keV) with timescales of several seconds are observed by the twin ELFIN Cubesats at low Earth orbit, while very‐oblique intense whistler‐mode waves are observed by the Time History of Events and Macroscale Interactions during Substorms E satellite at the conjugate magnetic equator. Our observation‐constrained test‐particle simulations reveal that the electron precipitation, particularly above 100 keV, results from high‐order resonant scattering by the very‐oblique whistler‐mode waves. Our study provides the first direct evidence for high‐order resonance driven precipitation, explaining a bursty precipitation event. The results demonstrate that high‐order resonant scattering could be important, not only in long‐term diffusion models, but also in models of short timescale events. 

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