Critical Point Theory on Partially Order
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Thomas Bartsch
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Article
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2001
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Elsevier Science
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English
โ 264 KB
We develop some abstract critical point theory in order to prove that boundary value problems like the model problem have infinitely many sign changing solutions ยฑ u k , k ยฅ N, which are not comparable, that is, u k -u l and u k +u l change sign for k ] l. We also show that there are no subsolution