Publications (57)
Task Aware Modulation using Representation Learning: An Approach for Few Shot Learning in Environmental Systems
Arvind Renganathan, Rahul Ghosh, Ankush Khandelwal +1
We introduce TAM-RL (Task Aware Modulation using Representation Learning), a novel multimodal meta-learning framework for few-shot learning in heterogeneous systems, designed for s…
Position-dependent mass Dirac equation and local Fermi velocity
Rahul Ghosh
We present a new approach to study (1+1)-dimensional Dirac equation in the background of an effective mass by exploiting the possibility of a position-dependent fermi velocity…
Semi-supervised Classification using Attention-based Regularization on Coarse-resolution Data
Guruprasad Nayak, Rahul Ghosh, Xiaowei Jia +2
Many real-world phenomena are observed at multiple resolutions. Predictive models designed to predict these phenomena typically consider different resolutions separately. This appr…
Weakly Supervised Classification Using Group-Level Labels
Guruprasad Nayak, Rahul Ghosh, Xiaowei Jia +1
In many applications, finding adequate labeled data to train predictive models is a major challenge. In this work, we propose methods to use group-level binary labels as weak super…
Multimodal Cross-Document Event Coreference Resolution Using Linear Semantic Transfer and Mixed-Modality Ensembles
Abhijnan Nath, Huma Jamil, Shafiuddin Rehan Ahmed +5
Event coreference resolution (ECR) is the task of determining whether distinct mentions of events within a multi-document corpus are actually linked to the same underlying occurren…
Correlation-Induced Topological Reconstruction in a Periodically Driven Kagome Mott Insulator
Rahul Ghosh, Subhajyoti Pal, Ganesh C Paul
We study the interplay between electronic correlations and circularly polarized periodic driving in the Hubbard model on a Kagome lattice. Using Brillouin-Wigner perturbation theor…
So (2, 1) algebra, local Fermi velocity, and position-dependent mass Dirac equation
Bijan Bagchi, Rahul Ghosh, Christiane Quesne
We investigate the (1+1)-dimensional position-dependent mass Dirac equation within the confines of so(2,1) potential algebra by utilizing the character of a spatial varying Fermi v…
Quantum sensing with discrete time crystals in the Lipkin-Meshkov-Glick Model
Rahul Ghosh, Bandita Das, Victor Mukherjee
Quantum phase transitions have been shown to be highly beneficial for quantum sensing, owing to diverging quantum Fisher information close to criticality. In this work we consider…
New solutions of Isochronous potentials in terms of exceptional orthogonal polynomials in heterostructures
Satish Yadav, Rahul Ghosh, Bhabani Prasad Mandal
Point canonical transformation (PCT) has been used to find out new exactly solvable potentials in the position-dependent mass (PDM) framework. We solve -D Schrödinger equation…
RAG for Geoscience: What We Expect, Gaps and Opportunities
Runlong Yu, Shiyuan Luo, Rahul Ghosh +3
Retrieval-Augmented Generation (RAG) enhances language models by combining retrieval with generation. However, its current workflow remains largely text-centric, limiting its appli…
Mapping smallholder cashew plantations to inform sustainable tree crop expansion in Benin
Leikun Yin, Rahul Ghosh, Chenxi Lin +9
Cashews are grown by over 3 million smallholders in more than 40 countries worldwide as a principal source of income. As the third largest cashew producer in Africa, Benin has near…
A study of generalized second law of thermodynamics in modified f(R) Horava-Lifshitz gravity
Surajit Chattopadhyay, Rahul Ghosh
This work investigates the validity of the generalized second law of thermodynamics in modified f(R) Horava-Lifshitz gravity proposed by Chaichian et al (2010) [Class. Quantum Grav…
Combining Satellite and Weather Data for Crop Type Mapping: An Inverse Modelling Approach
Praveen Ravirathinam, Rahul Ghosh, Ankush Khandelwal +3
Accurate and timely crop mapping is essential for yield estimation, insurance claims, and conservation efforts. Over the years, many successful machine learning models for crop map…
Signatures of topology in generic transport measurements for Rarita-Schwinger-Weyl semimetals
Ipsita Mandal, Shreya Saha, Rahul Ghosh
We investigate how the signatures of the topological properties of the bandstructures for nodal-point semimetals are embedded in the response coefficients, arising in two distinct…
Generating discrete time crystals through optimal control
Mrutyunjaya Sahoo, Rahul Ghosh, Bandita Das +3
In this work we use optimal control to generate Discrete Time Crystals (DTC) in generic many-body quantum systems. We define appropriate cost functions, which, when optimized, resu…
Reconstruction of gravity with ordinary and entropy-corrected type Holographic dark energy model
Rahul Ghosh, Ujjal Debnath
We have discussed the correspondence of the well-accepted gravity theory with two dark energy models : -type holographic dark energy [-type HDE] and entropy-co…
A BERT based Ensemble Approach for Sentiment Classification of Customer Reviews and its Application to Nudge Marketing in e-Commerce
Sayan Putatunda, Anwesha Bhowmik, Girish Thiruvenkadam +1
According to the literature, Product reviews are an important source of information for customers to support their buying decision. Product reviews improve customer trust and loyal…
Exactly solvable Stuart-Landau models in arbitrary dimensions
Pragjyotish Bhuyan Gogoi, Rahul Ghosh, Debashis Ghoshal +2
We use Clifford's geometric algebra to extend the Stuart-Landau system to dimensions and give an exact solution of the oscillator equations in the general case. At the super…
Refractive index profiles for a -symmetric optical structure
Bijan Bagchi, Rahul Ghosh, Sauvik Sen
By mapping the scalar Helmholtz equation (SHE) to the Schrodinger form we investigate the behaviour of optical structure when the refractive index distribution a…
Attention-augmented Spatio-Temporal Segmentation for Land Cover Mapping
Rahul Ghosh, Praveen Ravirathinam, Xiaowei Jia +3
The availability of massive earth observing satellite data provide huge opportunities for land use and land cover mapping. However, such mapping effort is challenging due to the ex…
CalCROP21: A Georeferenced multi-spectral dataset of Satellite Imagery and Crop Labels
Rahul Ghosh, Praveen Ravirathinam, Xiaowei Jia +3
Mapping and monitoring crops is a key step towards sustainable intensification of agriculture and addressing global food security. A dataset like ImageNet that revolutionized compu…
Clustering augmented Self-Supervised Learning: Anapplication to Land Cover Mapping
Rahul Ghosh, Xiaowei Jia, Chenxi Lin +2
Collecting large annotated datasets in Remote Sensing is often expensive and thus can become a major obstacle for training advanced machine learning models. Common techniques of ad…
Koopman Invertible Autoencoder: Leveraging Forward and Backward Dynamics for Temporal Modeling
Kshitij Tayal, Arvind Renganathan, Rahul Ghosh +2
Accurate long-term predictions are the foundations for many machine learning applications and decision-making processes. However, building accurate long-term prediction models rema…
Non-hermitian Dirac Hamiltonian in the presence of local Fermi velocity
Rahul Ghosh
We present a new approach to study a class of non-Hermitian (1+1)-dimensional Dirac Hamiltonian in the presence of local Fermi velocity. We apply the well known Nikiforov-Uvarov me…
Mini-Batch Learning Strategies for modeling long term temporal dependencies: A study in environmental applications
Shaoming Xu, Ankush Khandelwal, Xiang Li +9
In many environmental applications, recurrent neural networks (RNNs) are often used to model physical variables with long temporal dependencies. However, due to mini-batch training…
Robust Inverse Framework using Knowledge-guided Self-Supervised Learning: An application to Hydrology
Rahul Ghosh, Arvind Renganathan, Kshitij Tayal +6
Machine Learning is beginning to provide state-of-the-art performance in a range of environmental applications such as streamflow prediction in a hydrologic basin. However, buildin…
Uncertainty Quantification in Inverse Models in Hydrology
Somya Sharma Chatterjee, Rahul Ghosh, Arvind Renganathan +5
In hydrology, modeling streamflow remains a challenging task due to the limited availability of basin characteristics information such as soil geology and geomorphology. These char…
Spatiotemporal Classification with limited labels using Constrained Clustering for large datasets
Praveen Ravirathinam, Rahul Ghosh, Ke Wang +5
Creating separable representations via representation learning and clustering is critical in analyzing large unstructured datasets with only a few labels. Separable representations…
Quantum Phases in a Two-Dimensional Generalized interacting SSH Model
Rahul Ghosh
We study interaction-driven quantum phases in a two-dimensional generalized Su-Schrieffer-Heeger (SSH) defined on a square lattice with inequivalent nearest-neighbor hopping, next-…
Exceptional point in a coupled Swanson system
Bijan Bagchi, Rahul Ghosh, Sauvik Sen
We propose an interacting nonhermitian model described by a two-mode quadratic Hamiltonian along with an interaction term to locate and analyze the presence of an exceptional point…
Land Cover Mapping in Limited Labels Scenario: A Survey
Rahul Ghosh, Xiaowei Jia, Vipin Kumar
Land cover mapping is essential for monitoring global environmental change and managing natural resources. Unfortunately, traditional classification models are plagued by limited t…
Spin-imbalance induced buried topological edge currents in Mott \& topological insulator heterostructures
Rahul Ghosh, Subhajyoti Pal, Kush Saha +1
We theoretically investigate the heterostructure between a ferrimagnetic Mott insulator and a time-reversal invariant topological band insulator on the two-dimensional Lieb lattice…
Electric, thermal, and thermoelectric magnetoconductivity for Weyl/multi-Weyl semimetals in planar Hall set-ups induced by the combined effects of topology and strain
Leonardo Medel, Rahul Ghosh, Alberto MartÃn-Ruiz +1
We continue our investigation of the response tensors in planar Hall (or planar thermal Hall) configurations where a three-dimensional Weyl/multi-Weyl semimetal is subjected to the…
Dirac Hamiltonian in a supersymmetric framework
Bijan Bagchi, Rahul Ghosh
We investigate the most general form of the one-dimensional Dirac Hamiltonian in the presence of scalar and pseudoscalar potentials. To seek embedding of supersymmetry (SUSY)…
Direction-dependent conductivity in planar Hall set-ups with tilted Weyl/multi-Weyl semimetals
Rahul Ghosh, Ipsita Mandal
We compute the magnetoelectric conductivity tensors in planar Hall set-ups, which are built with tilted Weyl semimetals (WSMs) and multi-Weyl semimetals (mWSMs), considering all po…
Is GraphRAG Needed? From Basic RAG to Graph-/Agentic Solutions with Context Optimization
Long Chen, Ryan Razkenari, Yuxuan Zhou +5
As advanced RAG variants like GraphRAG and Agentic RAG emerge, one leading question is when and how to use them. Here, we introduce a framework for different RAG scenarios evaluati…
TelcoAI: Advancing 3GPP Technical Specification Search through Agentic Multi-Modal Retrieval-Augmented Generation
Rahul Ghosh, Chun-Hao Liu, Gaurav Rele +2
The 3rd Generation Partnership Project (3GPP) produces complex technical specifications essential to global telecommunications, yet their hierarchical structure, dense formatting,…
Dirac equation with Morse potetnial under the influence of position-dependent mass and local Fermi velocity
Bijan Bagchi, Rahul Ghosh
We solve the one-dimensional Dirac equation by taking into account the possibility of position-dependence in the mass function. We also take the Fermi velocity to act as a local va…
Towards Knowledge Guided Pretraining Approaches for Multimodal Foundation Models: Applications in Remote Sensing
Praveen Ravirathinam, Ajitesh Parthasarathy, Ankush Khandelwal +2
Self-supervised learning has emerged as a powerful paradigm for pretraining foundation models using large-scale data. Existing pretraining approaches predominantly rely on masked r…
Entity Aware Modelling: A Survey
Rahul Ghosh, Haoyu Yang, Ankush Khandelwal +5
Personalized prediction of responses for individual entities caused by external drivers is vital across many disciplines. Recent machine learning (ML) advances have led to new stat…
Hierarchically Disentangled Recurrent Network for Factorizing System Dynamics of Multi-scale Systems: An application on Hydrological Systems
Rahul Ghosh, Arvind Renganathan, Zac McEachran +6
We present a framework for modeling multi-scale processes, and study its performance in the context of streamflow forecasting in hydrology. Specifically, we propose a novel hierarc…
Quantifying Consistency in LLM Logical Reasoning via Structural Uncertainty
Baishali Chaudhury, Mengdie Flora Wang, Hyunji Hayley Park +3
Large language models can arrive at the same answer through reasoning paths that are unstable, contradictory, or difficult to rank consistently -- a failure mode especially prevale…
Stabilizing boundary time crystals through Non-markovian dynamics
Bandita Das, Rahul Ghosh, Victor Mukherjee
We study Boundary time crystals (BTCs) in the presence of non-Markovian dynamics. In contrast to BTCs observed in earlier works in the Markovian regime, we show that non-Markovian…
Learning Flow Distributions via Projection-Constrained Diffusion on Manifolds
Noah Trupin, Rahul Ghosh, Aadi Jangid
We present a generative modeling framework for synthesizing physically feasible two-dimensional incompressible flows under arbitrary obstacle geometries and boundary conditions. Wh…
Probabilistic Inverse Modeling: An Application in Hydrology
Somya Sharma, Rahul Ghosh, Arvind Renganathan +5
The astounding success of these methods has made it imperative to obtain more explainable and trustworthy estimates from these models. In hydrology, basin characteristics can be no…
Electric and thermoelectric response for Weyl and multi-Weyl semimetals in planar Hall configurations including the effects of strain
Rahul Ghosh, Ipsita Mandal
We investigate the response tensors in planar Hall (or planar thermal Hall) configurations such that a three-dimensional Weyl or multi-Weyl semimetal is subjected to the influence…
Analogue Hawking radiation as a tunneling in a two-level -symmetric system
Bijan Bagchi, Rahul Ghosh, Sauvik Sen
In the light of a general scenario of a two-level non-Hermitian -symmetric Hamiltonian we apply the tetrad-based method to analyze the possibility of analogue Hawking…
Learning to Retrieve for Environmental Knowledge Discovery: An Augmentation-Adaptive Self-Supervised Learning Framework
Shiyuan Luo, Runlong Yu, Chonghao Qiu +5
The discovery of environmental knowledge depends on labeled task-specific data, but is often constrained by the high cost of data collection. Existing machine learning approaches u…
Generalized Uncertainty principle and momentum-dependent effective mass Schrodinger equation
Bijan Bagchi, Rahul Ghosh, Partha Goswami
We show in this paper that the basic representations of position and momentum in a quantum mechanical system, that are guided by a generalized uncertainty principle and lead to a c…
Hierarchical Conditional Multi-Task Learning for Streamflow Modeling
Shaoming Xu, Arvind Renganathan, Ankush Khandelwal +9
Streamflow, vital for water resource management, is governed by complex hydrological systems involving intermediate processes driven by meteorological forces. While deep learning m…
Generalized second law of thermodynamics in the emergent universe for some viable models of f(T) gravity
Rahul Ghosh, Antonio Pasqua, Surajit Chattopadhyay
The present study is motivated by the study of reference [1], where the generalized second law of thermodynamics has been investigated for a flat FRW universe for two viable models…
PIER: Physics-Informed Environmental Retrieval for Time-Series Modeling
Shiyuan Luo, Runlong Yu, Chonghao Qiu +6
Accurate modeling of environmental systems is fundamental to scientific understanding and decision-making, yet remains challenging because observations are limited and physical dyn…
Linear response in planar Hall and thermal Hall setups for Rarita-Schwinger-Weyl semimetals
Rahul Ghosh, Firdous Haidar, Ipsita Mandal
We investigate the nature of the linear-response tensors in planar Hall and planar thermal Hall setups, where we subject a Rarita-Schwinger-Weyl (RSW) semimetal to the combined inf…
A Dark Energy Model with Generalized Uncertainty Principle in the Emergent, Intermediate and Logamediate Scenarios of the Universe
Rahul Ghosh, Surajit Chattopadhyay, Ujjal Debnath
This work is motivated by the work of Kim et al (2008), which considered the equation of state parameter for the new agegraphic dark energy based on generalized uncertainty princip…
The generalized second law of thermodynamics in f(R) gravity for various choices of scale factor
Rahul Ghosh, Surajit Chattopadhyay
The present study is aimed at investigating the validity of the generalized second law (GSL) of thermodynamics in gravity. Choosing [foll…
Behaviour of interacting Ricci dark energy in logarithmic f(T) gravity
Rahul Ghosh, Surajit Chattopadhyay
In the present work we have considered a modified gravity dubbed as "logarithmic gravity" and investigated the behavior of Ricci dark energy interacting with pressureless da…
CompAgent: An Agentic Framework for Visual Compliance Verification
Rahul Ghosh, Baishali Chaudhury, Hari Prasanna Das +5
Visual compliance verification is a critical yet underexplored problem in computer vision, especially in domains such as media, entertainment, and advertising where content must ad…