[分析] 非常數調和函數一定有正值??
正在自修Greene的Function Theory of One Complex Variable
第七章習題19要證明
Prove that there is no nonconstant harmonic function u:C->R
such that u(z)<=0 for all z in C
我的想法:
如果將u=-u代入 那這題變成no u(z)>=0 跟其他例題不合
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推
11/11 11:26, , 1F
11/11 11:26, 1F
→
11/11 11:27, , 2F
11/11 11:27, 2F
→
11/11 17:33, , 3F
11/11 17:33, 3F
→
11/11 17:34, , 4F
11/11 17:34, 4F
→
11/11 17:34, , 5F
11/11 17:34, 5F
假設u harmonic and bounded, let c be uppert bound
u(z) - c <= 0
Liouville => u is constant 所以反證
請問這樣的想法有不完整的地方嗎?
※ 編輯: subtropical (91.89.74.56), 11/12/2014 08:19:40