Conservation Laws of Evolution Equations: Generic Non-existence

AbstractEvolution-type partial differential equations in one space variable are formulated in terms of exterior differential systems. The space of conservation laws is discussed in this geometric context, and a familiar classical condition for conservation laws is derived. It is shown that the generic even-order evolution equation with one space variable possesses no conservation laws of order greater than the order of the equation

Conservation laws and normal forms of evolution equations

We study local conservation laws for evolution equations in two independent variables. In particular, we present normal forms for the equations admitting one or two low-order conservation laws. Examples include Harry Dym equation, Korteweg-de-Vries-type equations, and Schwarzian KdV equation. It is also shown that for linear evolution equations all their conservation laws are (modulo trivial conserved vectors) at most quadratic in the dependent variable and its derivatives.Comment: 16 page

Weaving Together: Reading (in) American Studies

Introduction to the thematic issue

Infinitely many local higher symmetries without recursion operator or master symmetry: integrability of the Foursov--Burgers system revisited

We consider the Burgers-type system studied by Foursov, w_t &=& w_{xx} + 8 w w_x + (2-4\alpha)z z_x, z_t &=& (1-2\alpha)z_{xx} - 4\alpha z w_x + (4-8\alpha)w z_x - (4+8\alpha)w^2 z + (-2+4\alpha)z^3, (*) for which no recursion operator or master symmetry was known so far, and prove that the system (*) admits infinitely many local generalized symmetries that are constructed using a nonlocal {\em two-term} recursion relation rather than from a recursion operator.Comment: 10 pages, LaTeX; minor changes in terminology; some references and definitions adde

Creative Openings and World-Making: Postcritique, Reparative Readings, and Anzaldúa’s Borderlands

This article examines postcritical and reparative readings of female same-sex narratives and proposes a diversification of reading practices. The approach toward f/f-narratives presented here shifts attention to queer literary visions by questioning the narrative of the “impossible woman” (Valerie Rohy) as well as the hegemony and omnipresence of the “hermeneutics of suspicion” (Paul Ricoeur) in literary and cultural studies. It aims at queering hierarchies of knowledge as well as practices of readings. Eventually, a postcritical reading of Gloria Anzaldúa’s Borderlands/La Frontera (1987) interrogates the text’s potential for creative openings and queer world-making by drawing on entanglements of past, present, and future

Cushmania: reconstructing queerness and celebrity of a nineteenth-century actress

Bei diesem Text handelt es sich um den unredigierten Vortrag der Konferenz „Digital Humanities and Gender History“.This text is the unedited presentation from the Digital Humanities and Gender History conference