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1. Spectrum of quantum KdV hierarchy in the semiclassical limit

   https://doi.org/10.1007/JHEP09(2022)169  

   Dymarsky, Anatoly; Kakkar, Ashish; Pavlenko, Kirill; Sugishita, Sotaro (September 2022, Journal of High Energy Physics)

   A<sc>bstract</sc> We employ semiclassical quantization to calculate spectrum of quantum KdV charges in the limit of large central chargec. Classically, KdV chargesQ_2n−1generate completely integrable dynamics on the co-adjoint orbit of the Virasoro algebra. They can be expressed in terms of action variablesI_k, e.g. as a power series expansion. Quantum-mechanically this series becomes the expansion in 1/c, while action variables become integer-valued quantum numbersn_i. Crucially, classical expression, which is homogeneous inI_k, acquires quantum corrections that include terms of subleading powers inn_k. At first two non-trivial orders in 1/cexpansion these “quantum” terms can be fixed from the analytic form ofQ_2n−1acting on the primary states. In this way we find explicit expression for the spectrum ofQ_2n−1up to first three orders in 1/cexpansion. We apply this result to study thermal expectation values ofQ_2n−1and free energy of the KdV Generalized Gibbs Ensemble. 

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2. Broken conformal window

   https://doi.org/10.1007/JHEP04(2025)152  

   Kondo, Dan; Murayama, Hitoshi; Noether, Bea; Varier, Digvijay Roy (April 2025, Journal of High Energy Physics)

   A<sc>bstract</sc> We show that near the edges of the conformal window of supersymmetric SU(N_c) QCD, perturbed by Anomaly Mediated Supersymmetry Breaking (AMSB), chiral symmetry can be broken depending on the initial conditions of the RG flow. We do so by perturbatively expanding around Banks-Zaks fixed points and taking advantage of Seiberg duality. Interpolating between the edges of the conformal window, we predict that non-supersymmetric QCD breaks chiral symmetry up toN_f≤ 3N_c− 1, while we cannot say anything definitive forN_f≥ 3N_cat this moment. 

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3. Measuring the Magnetic Field of a Coronal Mass Ejection from the Low to Middle Corona

   https://doi.org/10.3847/2041-8213/adfa71  

   Chen, Xingyao; Chen, Bin; Yu, Sijie; Mondal, Surajit; Stiefel, Muriel Zoë; Zhang, Peijin; Gary, Dale E; Krucker, Säm; Anderson, Marin M; Bowman, Judd D; et al (September 2025, The Astrophysical Journal Letters)

   Abstract A major challenge in understanding the initiation and evolution of coronal mass ejections (CMEs) is measuring the magnetic field of the magnetic flux ropes (MFRs) that drive CMEs. Recent developments in radio imaging spectroscopy have paved the way for diagnosing the CMEs’ magnetic field using gyrosynchrotron radiation. We present magnetic field measurements of a CME associated with an X5-class flare by combining radio imaging spectroscopy data in microwaves (1–18 GHz) and meter waves (20–88 MHz), obtained by the Owens Valley Radio Observatory’s Expanded Owens Valley Solar Array (EOVSA) and Long Wavelength Array (OVRO-LWA), respectively. EOVSA observations reveal that the microwave source, observed in the low corona during the initiation phase of the eruption, outlines the bottom of the rising MFR-hosting CME bubble seen in extreme ultraviolet and expands as the bubble evolves. As the MFR erupts into the middle corona and appears as a white-light CME, its meter-wave counterpart, observed by OVRO-LWA, displays a similar morphology. For the first time, using gyrosynchrotron spectral diagnostics, we obtain magnetic field measurements of the erupting MFR in both the low and middle corona, corresponding to coronal heights of 0.02 and 1.83R_⊙. The magnetic field strength is found to be around 300 G at 0.02R_⊙during the CME initiation and about 0.6 G near the leading edge of the CME when it propagates to 1.83R_⊙. These results provide critical new insights into the magnetic structure of the CME and its evolution during the early stages of its eruption. 

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4. Bridging two quantum quench problems — local joining quantum quench and Möbius quench — and their holographic dual descriptions

   https://doi.org/10.1007/JHEP08(2024)213  

   Kudler-Flam, Jonah; Nozaki, Masahiro; Numasawa, Tokiro; Ryu, Shinsei; Tan, Mao Tian (August 2024, Journal of High Energy Physics)

   A<sc>bstract</sc> We establish an equivalence between two different quantum quench problems, the joining local quantum quench and the Möbius quench, in the context of (1 + 1)-dimensional conformal field theory (CFT). Here, in the former, two initially decoupled systems (CFTs) on finite intervals are joined att= 0. In the latter, we consider the system that is initially prepared in the ground state of the regular homogeneous Hamiltonian on a finite interval and, aftert= 0, let it time-evolve by the so-called Möbius Hamiltonian that is spatially inhomogeneous. The equivalence allows us to relate the time-dependent physical observables in one of these problems to those in the other. As an application of the equivalence, we construct a holographic dual of the Möbius quench from that of the local quantum quench. The holographic geometry involves an end-of-the-world brane whose profile exhibits non-trivial dynamics. 

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5. The Redshift Evolution of the M _BH – M _* Scaling Relation: New Insights from Cosmological Simulations and Semianalytic Models

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

   Dattathri, Shashank; Natarajan, Priyamvada; Porras-Valverde, Antonio J; Burke, Colin J; Chen, Nianyi; Di_Matteo, Tiziana; Ni, Yueying (May 2025, The Astrophysical Journal)

   Abstract We study the coevolution of black holes (BHs) and their host galaxies in the ASTRIDandTNG300cosmological simulations and the DARKSAGEsemianalytic model (SAM), focusing on the evolution of the BH mass–stellar mass (M_BH–M_*) relation. Due to differences in the adopted subgrid modeling of BH seeding, dynamics, and feedback, the models differ in their predicted redshift evolution of theM_BH–M_*relation. We find that it is the interplay between the star formation rate (SFR) and the black hole accretion rate (BHAR) that drives the evolution of the mean relation. We define a quantity $\mathcal{R}$, the ratio between the specific BHAR and SFR (i.e., $\mathcal{R}\equiv$sBHAR/sSFR), and demonstrate that it is $\mathcal{R}$that governs the evolution of individual sources in theM_BH–M_*plane. The efficiency of BH growth versus stellar mass growth in the sSFR–sBHAR plane reflects the partitioning of gas between fueling star formation versus BH accretion. This partitioning depends on the implementation of BH dynamics and the nature of how black hole feedback quenches galaxies. In the cosmological simulations (ASTRIDandTNG300), the BHAR and SFR are intrinsically linked, resulting in a tightM_BH–M_*correlation, while the DARKSAGESAM produces a significantly larger scatter. We discuss these results in the context of recently discovered overmassive BHs and massive quenched galaxies at high redshift by the James Webb Space Telescope. 

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