Example of Unsymmetrical Metric: 2D Solutions

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Could anyone give me an example of two-dimensional metric which
doesn't have any Killing vector. It's not so easy to prove that
particular metric is indeed unsymmetrical - it may be only written
in unfortunately chosen coordinates :).

Any ideas how to attack this apparently simple problem.
 
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http://arxiv.org/abs/0910.0350

Section 4 has a spacetime with no Killing vectors, but it's not 2D. Maybe the reference where they show this will help?
 
Indeed hard to prove... Why not just try something absurd?
ds^2=e^{2x^2y}\left(dx^2+dy^2\right)+cosh^2\left(x^5\right) dx dy
 
Maybe this - matric induced form three dimensional flat euclidan space
on two dimensional ellipsoid with three unequal sides shouldn't posses any Killing
vectors. Am I right?
(none of killing vectors of eucliden space preserves this ellipsoid)
 
Damn, I'm stumped here, but interested.
 
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