Example 5.5 (The amoeba) . [04JX]
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Example 5.5 (The amoeba).
Take as a symplectomorphism the linear map
| (34) |
Then the fibration resulting from Proposition 5.4 can be written explicitly in the coordinates of the total space. We obtain:
| (35) |
where is as in (33). It is not difficult to see that sends to the surface in given by
which is, topologically, a pair of pants. Then the discriminant locus is
which has the shape in Figure 4. This example is topologically conjugate to the one in Example 2.9, before the surface has been twisted. For the discussion of the topology of the fibres in this example we refer to Example 2.9.