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1. Can the Hartree–Fock kinetic energy exceed the exact kinetic energy?

   https://doi.org/10.1063/5.0105684  

   Crisostomo, S.; Levy, M.; Burke, K. (October 2022, The Journal of Chemical Physics)

   The Hartree–Fock (HF) approximation has been an important tool for quantum-chemical calculations since its earliest appearance in the late 1920s and remains the starting point of most single-reference methods in use today. Intuition suggests that the HF kinetic energy should not exceed the exact kinetic energy; but no proof of this conjecture exists, despite a near century of development. Beginning from a generalized virial theorem derived from scaling considerations, we derive a general expression for the kinetic energy difference that applies to all systems. For any atom or ion, this trivially reduces to the well-known result that the total energy is the negative of the kinetic energy and, since correlation energies are never positive, proves the conjecture in this case. Similar considerations apply to molecules at their equilibrium bond lengths. We use highly precise calculations on Hooke’s atom (two electrons in a parabolic well) to test the conjecture in a nontrivial case and to parameterize the difference between density functional and HF quantities, but find no violations of the conjecture. 

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2. Comparing kinetic proofreading and kinetic segregation for T cell receptor activation

   https://doi.org/10.1103/physrevresearch.7.023003  

   Moffett, Alexander S; Ganzinger, Kristina A; Eckford, Andrew W (April 2025, Physical Review Research)

   The T cell receptor (TCR) is a key component of the adaptive immune system, recognizing foreign antigens (ligands) and triggering an immune response. To explain the high sensitivity and selectivity of the TCR in discriminating “self” from “non-self” ligands, most models evoke kinetic proofreading (KP) schemes, however it is unclear how competing models used for TCR triggering, such as the kinetic segregation (KS) model, influence KP performance. In this paper, we consider two different TCR triggering models and their influence on subsequent KP-based ligand discrimination by the TCR: a classic conformational change model (CC-KP), where ligand-TCR binding is strictly required for activation, and the kinetic segregation model (KS-KP), where only residence of the TCR within a close contact devoid of kinases is required for its activation. Building on previous work, our computational model permits a head-to-head comparison of these models . While we find that both models can be used to explain the probability of TCR activation across much of the parameter space, we find biologically important regions in the parameter space where significant differences in performance can be expected. Furthermore, we show that the available experimental evidence may favor the KS-KP model over CC-KP. Our results may be used to motivate and guide future experiments to determine accurate mathematical models of TCR function. Published by the American Physical Society2025 

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3. Thermodynamic and Kinetic Properties of the Lithium–Silver System

   https://doi.org/10.1021/acs.chemmater.4c01903  

   Thomas, Jeremiah; Behara, Sesha_Sai; Van_der_Ven, Anton (August 2024, Chemistry of Materials)
4. Wave turbulence and the kinetic equation beyond leading order

   https://doi.org/10.1103/PhysRevE.109.064127  

   Rosenhaus, Vladimir; Smolkin, Michael (June 2024, Physical Review E)
5. Partitioning of Kinetic Energy in the Arctic Ocean's Beaufort Gyre: BEAUFORT GYRE KINETIC ENERGY

   https://doi.org/10.1029/2018JC014037  

   Zhao, Mengnan; Timmermans, Mary-Louise; Krishfield, Richard; Manucharyan, Georgy (July 2018, Journal of Geophysical Research: Oceans)