With respect to integrable partial differential equations, gauge transformations of Lax pairs are critical tools that can be used to extend integrable equations. We investigate gauge transformations for discrete integrable equations. By applying twice gauge transformations to the Lax pair of the discrete Korteweg—de Vries (KdV) equation, we obtain discrete modified KdV and discrete modified KdV-Ⅱ equations. Then, by introducing the potential variables, we obtain potential forms of those two equations, which are proven to satisfy the three-dimensional consistency property.
ZHANG Haifei
,
ZHANG Cheng
,
ZHANG Dajun
. Gauge transformations for discrete KdV equations[J]. Journal of Shanghai University, 2025
, 31(6)
: 1067
-1075
.
DOI: 10.12066/j.issn.1007-2861.2268
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