# ISOMETRIC REFLECTIONS IN TWO DIMENSIONS AND DUAL L1-STRUCTURES

• Garcia-Pacheco, Francisco J. (Department of Mathematics Texas A&M University)
• Published : 2012.11.30

#### Abstract

In this manuscript we solve in the positive a question informally proposed by Enflo on the measure of the set of isometric reflection vectors in non-Hilbert 2-dimensional real Banach spaces. We also reformulate equivalently the separable quotient problem in terms of isometric reflection vectors. Finally, we give a new and easy example of a real Banach space whose dual has a non-trivial L-summand that does not come from an M-ideal in the predual.

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#### Cited by

1. An approach to a Ricceriʼs Conjecture vol.159, pp.15, 2012, https://doi.org/10.1016/j.topol.2012.07.010
2. A simple equivalent reformulation of the separable quotient problem vol.148, pp.1, 2016, https://doi.org/10.1007/s10474-015-0555-0