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Premashis Kumar

Ph.D. Theoretical Physics · Postdoctoral Researcher

Theoretical physicist establishing connections between thermodynamics and dynamics across spatiotemporal organisation, emergent behaviour, and nonlinear phenomena in biologically relevant nonequilibrium systems.

I develop analytical and computational frameworks to understand how microscopic interactions and thermodynamic constraints give rise to spatiotemporal organisation and emergent behaviour in chemically interacting systems. My work focuses on chemical reaction networks and reaction–diffusion systems, with particular emphasis on mechanisms that underlie biologically relevant pattern formation, collective dynamics, and self-organisation in complex nonequilibrium systems.

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9 Papers · Total Publications

6 first-author · 1 sole-author

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6+ Years · Research Experience

JRF → SRF → Postdoc

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Contact & Profiles

📧 [email protected] · Google Scholar · ResearchGate · LinkedIn

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Quick Navigation

🔬 Research Projects · 📚 Publications · 🔭 Current Interests · 🗓️ Experience · 🎓 Education · 🛠️ Skills · 🏅 Honors · 🌐 Conferences · 📝 Service

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🔬 Research Projects

My research spans four interconnected programmes — each addressing a distinct facet of nonequilibrium physics: from thermodynamic constraints governing instability in active matter, to the energetic cost of biological pattern formation, the emergent collective behaviour of coupled oscillators, and the fidelity–dissipation trade-offs in biochemical decision-making.

A — Instability Mechanisms in Thermodynamically Consistent Active Reaction–Diffusion Systems

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P. Kumar, M. Esposito & T. Aslyamov · arXiv:2601.12955 · University of Luxembourg · 2026 · PREPRINT

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A thermodynamically consistent reaction–diffusion framework is developed to derive fundamental constraints on admissible instability mechanisms in chemically interacting systems. By explicitly incorporating molecular interactions within both diffusion and reaction processes, the classical Cross–Hohenberg classification is revisited from a thermodynamic perspective.

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Key Findings

• Proved analytically that only Type I (stationary) and Type III (oscillatory–stationary) instabilities are admissible — Types II and IV are thermodynamically forbidden
• Revealed that energetic contributions do not directly drive instabilities, but regulate them implicitly through steady-state concentrations
• Demonstrated that competing instability modes generate rich spatiotemporal organisation </aside>

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Core Contribution — Establishes thermodynamic constraints that fundamentally restrict admissible instability mechanisms in active reaction–diffusion systems.

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B — Thermodynamic Cost of Spatiotemporal Patterns with Cross Diffusion

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Phys. Rev. E 101, 042204 (2020) · Phys. Rev. E 104, 014221 (2021) · ChemPhysChem 24, e202200643 (2023) · 3 PAPERS

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The energetic cost and entropy production underlying spatiotemporal pattern formation in reaction–diffusion systems with cross diffusion are characterised. The analysis focuses on overlapping Turing–Hopf instabilities and traveling wave dynamics in chemically and biologically realistic settings.

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Key Findings

• Established that entropy production scales with global concentration dynamics, linking macroscopic pattern evolution to thermodynamic dissipation
• Demonstrated that diffusive contributions to entropy production become negligible in traveling wave regimes
• Shown that finite boundary effects become thermodynamically significant at the Benjamin–Feir instability onset </aside>

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Core Contribution — Provides a thermodynamic characterisation of pattern formation, linking spatiotemporal dynamics with dissipation and energetic cost.

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