Role of effective temperature in selecting the tangential direction

Determine whether the effective temperature is essential for selecting the tangential direction to the second-order phase-transition line at the current-driven tricritical point, or whether the agreement with Landau-theory critical exponents is solely a consequence of tangential approach.

Background

The fixed-T*/T path approaches the tricritical point tangentially to the second-order phase-transition line and produces mean-field critical exponents in both the chiral-symmetry-broken and chiral-symmetry-restored phases. The paper leaves unresolved whether fixing the effective-temperature ratio causes the relevant tangency and thereby selects Landau-like scaling, or whether the agreement with Landau theory follows from tangency independently of the effective temperature.

References

Whether the effective temperature plays an essential role in selecting this tangential direction, or the agreement merely reflects the tangency itself, remains to be clarified.

— Landau theory, effective temperature, and tricritical phenomena in a holographic nonequilibrium steady state  (2608.23378 - Kanazawa et al., 24 Aug 2026) in Section 5, Conclusions and discussion

Several directions remain open. First, it would be important to determine the remaining tricritical exponents, in particular the crossover exponent, and to test the tricritical scaling relations at the current-driven TCP.

— Landau theory, effective temperature, and tricritical phenomena in a holographic nonequilibrium steady state  (2608.23378 - Kanazawa et al., 24 Aug 2026) in Section 5, Conclusions and discussion

Last but not least, a nontrivial extension of the Landau theory for the current-driven TCP should be addressed in future work.

— Landau theory, effective temperature, and tricritical phenomena in a holographic nonequilibrium steady state  (2608.23378 - Kanazawa et al., 24 Aug 2026) in Section 5, Conclusions and discussion