On Hölder continuity and equivalent formulation of intrinsic Harnack estimates for an anisotropic parabolic degenerate prototype equation.

We give a proof of H older continuity for bounded local weak solutions to the equation ut =\sum_{i=1}^N (|u_{x_i}|^{p_i−2} u_{x_i} )_{x_i} , in Ω × [0, T], with Ω ⊂⊂ R^N under the condition 2 < pi < p(1 + 2/N) for each i = 1, .., N, being p the harmonic mean of the pi's, via recently discovered intrinsic Harnack estimates. Moreover we establish equivalent forms of these Harnack estimates within the proper intrinsic geometry.

[1]  V. Vespri,et al.  An Introduction to Barenblatt Solutions for Anisotropic p-Laplace Equations , 2020, Springer INdAM Series.

[2]  V. Vespri,et al.  A new short proof of regularity for local weak solutions for a certain class of singular parabolic equations , 2020, 2003.00746.

[3]  P. Bousquet,et al.  Lipschitz regularity for orthotropic functionals with nonstandard growth conditions , 2018, Revista Matemática Iberoamericana.

[4]  V. Vespri,et al.  Anisotropic Sobolev embeddings and the speed of propagation for parabolic equations , 2018, Journal of Evolution Equations.

[5]  Paolo Marcellini,et al.  Regularity for scalar integrals without structure conditions , 2018 .

[6]  U. Gianazza,et al.  Remarks on Local Boundedness and Local Holder Continuity of Local Weak Solutions to Anisotropic p-Laplacian Type Equations , 2016, 1610.09509.

[7]  U. Gianazza,et al.  Harnack's Inequality for Degenerate and Singular Parabolic Equations , 2011 .

[8]  Mohammed Kbiri Alaoui,et al.  On Degenerate Parabolic Equations , 2011, Int. J. Math. Math. Sci..

[9]  U. Gianazza,et al.  Alternative Forms of the Harnack Inequality for Non-Negative Solutions to Certain Degenerate and Singular Parabolic Equations , 2009 .

[10]  C. Schmeiser,et al.  A note on the anisotropic generalizations of the Sobolev and Morrey embedding theorems , 2009 .

[11]  I. Skrypnik Removability of an isolated singularity for anisotropic elliptic equations with absorption , 2008 .

[12]  U. Gianazza,et al.  Harnack estimates for quasi-linear degenerate parabolic differential equations , 2008 .

[13]  L. Xiting,et al.  Boundedness of Solutions of Parabolic Equations With Anisotropic Growth Conditions , 1997, Canadian Journal of Mathematics.

[14]  Paolo Marcellini Regularity and existence of solutions of elliptic equations with p,q-growth conditions , 1991 .

[15]  Paolo Marcellini Regularity of minimizers of integrals of the calculus of variations with non standard growth conditions , 1989 .

[16]  M. Giaquinta Growth conditions and regularity, a counterexample , 1987 .

[17]  A. Korolev On the boundedness of generalized solutions of elliptic differential equations , 1983 .

[18]  J. Moser A Harnack inequality for parabolic di2erential equations , 1964 .

[19]  Paolo Marcellini Regularity under general and \begin{document}$ p,q- $\end{document} growth conditions , 2020 .

[20]  S. Antontsev,et al.  Evolution PDEs with Nonstandard Growth Conditions , 2015 .

[21]  M. Ruzicka,et al.  Electrorheological Fluids: Modeling and Mathematical Theory , 2000 .

[22]  B. Pini Sulla soluzione generalizzata di Wiener per il primo problema di valori al contorno nel caso parabolico , 1954 .