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The duality between electric and magnetic dipoles in electromagnetism only partly applies to condensed matter. In particular, the elementary excitations of the magnetic and ferroelectric orders, namely magnons and ferrons, respectively, have received asymmetric attention from the condensed matter community in the past. In this Perspective, we introduce and summarize the current state of the budding field of “ferronics.” We argue that the introduction of dipole-carrying elementary excitations allows the modeling of many observables and potentially leads to applications in thermal, information, and communication technologies. 

Abstract Ecotourism provides an opportunity to experience nature that may promote its conservation. Ecotourists photograph wildlife, and photography plays an important role in focusing public's attention on nature. Although photography is believed to be a low‐impact activity, how the visual stimulus of cameras influences wildlife remains unknown. Since animals are known to fear eyes pointed towards them because of similarity to predator eyes, we predicted that cameras with zoom lens would increase vigilance. Using yellow‐bellied marmots (Marmota flaviventer) and adopting a behavioural approach to identify marmots' response to photography, we experimentally quantified proportion of time allocated to vigilance during foraging and flight initiation distance (FID, the distance at which a marmot started to flee from an approaching human) towards humans with and without a camera. We focused on time allocated to vigilance measured in three ways: the proportion of time when marmots moved their head and body towards observers (looking towards observer), the proportion of time when marmots moved their head away from observers (looking away from observer) and the total vigilance (sum of looking towards and away from observer). While a camera was pointed at a marmot, individuals allocated more time to looking towards the observer and less time to looking away from the observer than they did without a camera. However, the total proportion of time allocated to vigilance was not different when marmots were approached by humans with and without a camera. Additionally, whether or not an observer was carrying a camera had no effect on FID. Our results indicated that cameras distracted marmots but did not influence their subsequent risk assessment; marmots may be curious about cameras but were not threatened by them. However, capturing an individual's attention may reduce their ability to look out for predators and thus may increase vulnerability to predation. Regulating photography in locations where predation risk is high or vulnerable species ranges' overlap with humans may be required. 

A<sc>bstract</sc> The measurements of the Higgs boson (H) production cross sections performed by the CMS Collaboration in the four-lepton (4ℓ, ℓ= e,μ) final state at a center-of-mass energy$$\sqrt{s}$$= 13.6 TeV are presented. These measurements are based on data collected with the CMS detector at the CERN LHC in 2022, corresponding to an integrated luminosity of 34.7 fb⁻¹. Cross sections are measured in a fiducial region closely matching the experimental acceptance, both inclusively and differentially, as a function of the transverse momentum and the absolute value of the rapidity of the four-lepton system. The H → ZZ → 4ℓinclusive fiducial cross section is measured to be$${2.89}_{-0.49}^{+0.53}{\left({\text{stat}}\right)}_{-0.21}^{+0.29}\left({\text{syst}}\right)$$fb, in agreement with the standard model expectation of$${3.09}_{-0.24}^{+0.27}$$fb. 

A measurement of the Higgs boson mass and width via its decay to two $Z$bosons is presented. Proton-proton collision data collected by the CMS experiment, corresponding to an integrated luminosity of $138{\mathrm{fb}}^{-1}$at a center-of-mass energy of 13 TeV, is used. The invariant mass distribution of four leptons in the on-shell Higgs boson decay is used to measure its mass and constrain its width. This yields the most precise single measurement of the Higgs boson mass to date, $125.04\pm 0.12\mathrm{GeV}$, and an upper limit on the width ${\mathrm{\Gamma }}_H<330\mathrm{MeV}$at 95% confidence level. A combination of the on- and off-shell Higgs boson production decaying to four leptons is used to determine the Higgs boson width, assuming that no new virtual particles affect the production, a premise that is tested by adding new heavy particles in the gluon fusion loop model. This result is combined with a previous CMS analysis of the off-shell Higgs boson production with decay to two leptons and two neutrinos, giving a measured Higgs boson width of ${3.0}_{-1.5}^{+2.0}\mathrm{MeV}$, in agreement with the standard model prediction of 4.1 MeV. The strength of the off-shell Higgs boson production is also reported. The scenario of no off-shell Higgs boson production is excluded at a confidence level corresponding to 3.8 standard deviations. © 2025 CERN, for the CMS Collaboration2025CERN 

A<sc>bstract</sc> A search for heavy, long-lived, charged particles with large ionization energy loss within the silicon tracker of the CMS experiment is presented. A data set of proton-proton collisions at a center of mass energy at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV, collected in 2017 and 2018 at the CERN LHC, corresponding to an integrated luminosity of 101 fb⁻¹, is used in this analysis. Two different approaches for the search are taken. A new method exploits the independence of the silicon pixel and strips measurements, while the second method improves on previous techniques using ionization to determine a mass selection. No significant excess of events above the background expectation is observed. The results are interpreted in the context of the pair production of supersymmetric particles, namely gluinos, top squarks, and tau sleptons, and of the Drell-Yan pair production of fourth generation (τ′) leptons with an electric charge equal to or twice the absolute value of the electron charge (e). An interpretation of a Z’ boson decaying to twoτ′ leptons with an electric charge equal to 2eis presented for the first time. The 95% confidence upper limits on the production cross section are extracted for each of these hypothetical particles. 

Nuclear medium effects on $B^{+}$meson production are studied using the binary-collision scaled cross section ratio between events of different charged-particle multiplicities from proton-lead collisions. Data, collected by the CMS experiment in 2016 at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{\mathrm{NN}}}=8.16\mathrm{TeV}$, corresponding to an integrated luminosity of $175{\mathrm{nb}}^{-1}$, were used. The scaling factors in the ratio are determined using a novel approach based on the $Z\to {\mu }^{-}{\mu }^{+}$cross sections measured in the same events. The scaled ratio for $B^{+}$is consistent with unity for all event multiplicities, putting stringent constraints on nuclear modification for heavy flavor. © 2025 CERN, for the CMS Collaboration2025CERN