Indian Institute of Technology Gandhinagar

Preparing subradiant steady states of collectively emitting quantum two-level emitters (TLEs) is hindered by their dark, weakly interacting nature. Existing approaches rely on patterned driving, local control, or structured environments. We propose a platform-independent protocol based on projective measurements on a single TLE. For permutation-symmetric ensembles, a single measurement yields appreciable occupation of single-excitation subradiant steady states. For generic arrays, repeated measurements on one emitter drive the unmeasured TLEs into a nearly pure state with large overlap with the subradiant Dicke subspace.

Low-lying coral reef islands are increasingly threatened by sea-level rise and intensifying monsoon events, leading to heightened risks of coastal inundation, erosion, and consequent impacts on island habitability and human migration. Despite these challenges, such islands exhibit dynamic and non-uniform responses governed by local hydrodynamics and environmental conditions. The Western Indian Ocean is especially vulnerable, with models projecting anomalously higher rates of sea level rise and storm frequency compared to the global average. Within this context, the low-lying islands of the Lakshadweep Archipelago provide an essential case study for understanding island vulnerability and resilience. This study presents a decadal-scale analysis (2003–2022) of ten islands in the Lakshadweep Archipelago, focusing on spatial variations in island area and their relationship with global and regional environmental factors. High-resolution satellite imagery (CNES Airbus, 0.3–0.7 m) was used to examine shoreline morphological changes on both inhabited (Bitra, Androth, Minicoy, Agatti, Kavaratti, Kalpeni) and uninhabited (Bangaram, Thinnakara, Suheli, Kalpetti) islands. Islands were categorized by size, distinguishing large (>1 km², Minicoy and Androth, Kavaratti, Agatti, Kalpeni) from small (<1 km²) islands, and by habitability to assess anthropogenic impacts. Results reveal that all islands, regardless of habitation, experienced specific changes in area: small islands showed up to 30% sediment migration, however, without losing area—especially pronounced from 2007 to 2017, coinciding with severe El Niño and low-amplitude Indian Ocean Dipole events. While the large islands lost up to 5% of their area, attributed to both natural and human influences. These findings indicate that small islands face moderate risk due to sediment migration, while large islands are moderately to highly vulnerable, influenced by persistent erosion and anthropogenic factors. Spatial patterns of vulnerability, particularly in the southern zones, underline the need for targeted mitigation and adaptation strategies. Importantly, regional drivers such as monsoon intensity play a decisive role in shoreline resilience, differentiating these islands from their global counterparts. By identifying areas of risk and proposing conceptual models for adaptation, this study offers insights for assessing the habitability of coral reef islands in the context of ongoing climate change.

Mare Australe (47.77°S, 91.99°E) is a distinctive volcanic province (diameter ~1000km) at the eastern nearside and farside boundary of the Moon. The basalts of the region were considered a part of mare filling volcanism inside an ‘Australe Basin’ due to the circular arrangement of its 248 basaltic patches [1]. The proposed Australe Basin, however, lacks any discernible topographic signatures, a ring morphology, and a central positive Bouguer anomaly typically associated with the lunar impact basins. The results from the GRAIL mission and geological investigations revealed the presence of a ~880 km diameter impact structure in the northern part of Mare Australe, naming it the Australe North Basin (35.5°S, 96°E) [2, 3]. The Mare Australe basalts are dominantly emplaced outside this newly discovered Australe North Basin, which is perplexing. In this study, we carry out an extensive compositional investigation of the previously uncharacterized Australe region using hyperspectral data from the Moon Mineralogical Mapper (M3) onboard Chandrayaan-1. We investigate both mare and non-mare units in the region to understand their mineralogy in the given geological context. The spectral investigation reveals that despite widespread volcanism, the region lacks the presence of high-Ca pyroxene. Instead, the basalts are primarily composed of low to intermediate Ca-pyroxene in comparison to the rest of the lunar basalts, displaying their unique mineralogical signature. These findings provide new insights into the nature and origin of the atypical volcanism on the Moon in the Australe Region and highlight the distinct geological environment of Mare Australe responsible for the same. This study offers important implications for understanding lunar volcanic evolution and its relationship with impact processes.

The principal aim of the present work is to explore limit theorems for small random perturbations of dynamical systems with periodic impulse effects, in the limit of vanishing noise intensity. We start with a system whose time evolution is governed by a nonlinear ordinary differential equation in between impulses, and a nonlinear resetting map at impulses; the latter are assumed to arrive in a time-periodic manner. We next consider small state-dependent Brownian perturbations of this system and explore the zero noise limit on finite, but arbitrary, time horizons. For the resulting stochastic system with impulse effects, we prove convergence to the underlying deterministic impulsive system as the noise goes to zero. More importantly, we prove convergence of the rescaled fluctuation process about the deterministic limit in a strong pathwise sense on finite time intervals to a limiting fluctuation process governed by a linear time-dependent stochastic differential equation in between impulses and a linear time-dependent resetting map at this http URL results are illustrated numerically for a periodically kicked nonlinear pendulum with state-dependent kick sizes.