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Un mecanismo mínimo para el efecto Mpemba impulsado por la transición de fase en sistemas con un solo parámetro de
Li Li1, Ji-Xuan Hou1
1School of Physics, Southeast University, Nanjing 211189, China.
Entropy (Basel, Switzerland)
|January 28, 2026
Resumen
El efecto Mpemba, por el cual el agua caliente se congela más rápido que el fría, se explica mediante un nuevo modelo. Este mecanismo muestra cómo la temperatura inicial afecta las vías de enfriamiento y la cinética de la transición de fase.
Área de la Ciencia:
- Física
- Termodinámica
- Mecánica Estadística
Sus antecedentes:
- El efecto Mpemba describe la observación contraintuitiva de que el agua más caliente puede congelarse más rápido que el agua más fría.
- Los mecanismos subyacentes de este fenómeno no se comprenden completamente, y se han propuesto varias teorías.
Objetivo del estudio:
- Proponer y demostrar un mecanismo simple y general para el efecto Mpemba impulsado por transiciones de fase.
- Explicar el efecto utilizando un solo parámetro de orden y la dinámica Markoviana estándar.
Principales métodos:
- Se desarrolló un modelo teórico basado en paisajes de energía libre y vías de relajación distintas.
- Se utilizó el modelo extendido de espín-1 de Nagle-Kardar para ilustrar el mecanismo.
- Se realizaron extensas simulaciones de Monte Carlo para validar los hallazgos.
Principales resultados:
- Se demostró que una temperatura inicial más alta puede conducir a un enfriamiento más rápido al evitar estados metaestables.
- Se demostró que la posición del estado inicial en el espacio de parámetros de orden influye en la cinética de la transición de fase.
- Se confirmó un efecto Mpemba robusto en simulaciones, y los sistemas más calientes alcanzaron la fase final más rápido.
Conclusiones:
- El estudio proporciona una explicación mínima y clara para el efecto Mpemba basada en la dinámica de la transición de fase.
- Los hallazgos resaltan la importancia de las condiciones iniciales y la topografía del paisaje de energía libre en la determinación de las tasas de enfriamiento.
- Este trabajo ofrece una nueva perspectiva sobre los fenómenos de enfriamiento anómalos.
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