##  [Onsager Reciprocal Relations](/index.php/onsager-reciprocal-relations) 

  ##  [Onsager Reciprocal Relations](https://natural.quantumdictionary.io/onsager-reciprocal-relations-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

Symmetry relations among linear transport coefficients that hold in the near‑equilibrium linear response regime when microscopic dynamics respect time‑reversal symmetry.

 

 

 

 

 





 

 



 ##  [Onsager Reciprocal Relations](https://engineering.quantumdictionary.io/onsager-reciprocal-relations-1) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A set of linear symmetry constraints on the transport coefficients L_ij that relate thermodynamic fluxes J_i to forces X_j in near-equilibrium irreversible thermodynamics, stating that for systems whose microscopic dynamics are time-reversal symmetric the phenomenological matrix is symmetric (L_ij = L_ji), with a generalized Onsager–Casimir form (L_ij = ε_i ε_j L_ji) when variables have defined pa