Reviews of topical problems

K.V. Lvov, S.Yu. Stremoukhov “Atom in intense laser fields: from the generation of coherent short-wavelength radiation to the nonlinear properties of the gas medium” Phys. Usp. 69 (4) (2026)

A.S. Ilin, A.N. Matsukatova, M.N. Martyshov, A.V. Emelyanov, V.V. Rylkov, V.A. Demin, P.A. Forsh, P.K. Kashkarov, M.V. Kovalchuk “Memristors for neuromorphic computing systems: basic parameters and methods of their optimization” Phys. Usp. 69 (4) (2026)

Physics of our days

A.V. Butenko, V.A. Lebedev, E.M. Syresin, G.V. Trubnikov “Commissioning of Collider NICA and formation of first heavy ion beams” Phys. Usp. 69 (4) (2026)

Instruments and methods of investigation

T.V. Kulevoy, S.V. Grigoriev, N.A. Kovalenko, K.A. Pavlov, E.V. Moskvin, N.A. Grigoryeva, E.A. Kravtsov, V.A. Skalyga, I.V. Izotov, G.N. Kropachev, A.L. Sitnikov, N.V. Mushnikov, L.V. Kravchuk “Compact neutron source DARIA in Russian strategy for developing neutron research” Phys. Usp. 69 (4) (2026)

Methodological notes

E.H. Lock, S.V. Gerus, A.V. Sadovnikov “Superresolution effect and resolvability criterion for the waves in anisotropic media” Phys. Usp. 69 (4) (2026)

B.P. Kondratyev “From Kepler's ellipses — to R-toroids” Phys. Usp. 69 (4) (2026)

V.S. Beskin, A.Yu. Istomin, F.A. Kniazev, T.I. Khalilov “Synchrotron radiation in nonuniform magnetic field” Phys. Usp. 69 (4) (2026)

Scientific news

Yu.N. Eroshenko “Physics news on the Internet: April 2026” Phys. Usp. 69 (4) (2026)

Personalia

S.V. Garnov, N.S. Ginzburg, M.Yu. Glyavin, V.I. Ilgisonis, V.V. Kveder, V.V. Kocharovskii, Z.F. Krasil’nik, A.V. Krasilnikov, A.G. Litvak, E.A. Mareev, A.M. Sergeev, M.I. Yalandin “Grigory Gennadievich Denisov (on his 70th birthday)” Phys. Usp. 69 (4) (2026)