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3 votes
1 answer
160 views

Definitions of weak solutions for quasilinear wave equations

I am learning the shock problem for the balance system (perhaps not conserved, see, e.g., "Ingo Muller, Tommaso Ruggeri. Rational Extended Thermodynamics") and just have a question on the ...
lsb's user avatar
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0 votes
0 answers
46 views

Conservation law for generic linear hyperbolic PDEs?

Consider the wave equation: $$ u_{tt} = \Delta u, \text{ on }U\times [0,T], u=0\text{ on }\partial U\times[0,T]. $$ To prove the only solution for the zero initial condition is zero, we only need to ...
Ma Joad's user avatar
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3 votes
1 answer
404 views

What does it mean by "converges boundedly"?

On page 92 of the book Hyperbolic Conservation Laws in Continuum Physics by C. M. Dafermos, there is a theorem 4.6.1 which says Under some assumptions, suppose a sequence of solutions $U_{\mu_k}$ to ...
Ma Joad's user avatar
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1 vote
1 answer
79 views

Assumptions on the flux of a conservation law required to obtain an entropy inequality

On page 87 of the book Hyperbolic Conservation Laws in Continuum Physics by C. M. Dafermos, there is a theorem which I summarise as follows Theorem. (Theorem 4.5.2 in the book.) Let $U$ be a weak ...
Ma Joad's user avatar
  • 1,755
1 vote
1 answer
83 views

Front tracking approximations and existence of solutions to conservation law PDEs

This question is about page 38-42 of these notes on censervation laws, more precisely PDEs of the form $u_t + [f(u)]_x =0.$ In this section of the note, the author provides a proof of the existence of ...
Ma Joad's user avatar
  • 1,755
1 vote
2 answers
376 views

Banach space-valued test functions in the definition of a weak solution of a PDE problem

In the literature about PDEs it is easy to find books that talk about weak solutions of a partial differential equations. A short reminder of the usual definition is given bellow. More information ...
Mark's user avatar
  • 657
7 votes
1 answer
895 views

Comparing weak and strong solutions of a PDE problems

A few days ago I was reading the paper: "Relative entropies, suitable weak solutions, and weak-strong uniqueness for the compressible Navier-Stokes system" - Feireisl, Jin, Novotny, 2012 [Arxiv]. ...
Mark's user avatar
  • 657
1 vote
2 answers
247 views

Transformation from the PDE problem with a source to the PDE problem without it and viceversa

In the study of nonlinear conservation laws a lot of time I work on the two problems given bellow: $$(1) \hspace{1cm} \begin{cases} u_t+(f_{1}(u))_x=\lambda \cdot g(u) \\[2ex] u(x,0)=h_{1}(x) \...
Mark's user avatar
  • 657
1 vote
0 answers
162 views

Reference request for a paper with Vanishing viscosity method and smooth approximation of initial data

I am trying to find the papers/books/notes that study problem (1),(3) given bellow using the vanishing viscosity method. I am especially interested in solutions in Sobolev spaces. More detailed ...
Mark's user avatar
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