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Timeline for A Cauchy-Schwarz inequality

Current License: CC BY-SA 3.0

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Oct 19, 2018 at 18:08 answer added Qiang Zhang timeline score: 1
Apr 13, 2017 at 12:19 history edited CommunityBot
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Nov 27, 2016 at 19:34 comment added Fan Zheng Sorry but I missed a factor $\bar\kappa-\min\kappa_i$, but fortunately it appears on both sides of the inequality, so it still works. But I guess you may have a different argument in mind because it's really a stretch to call the above argument C-S.
Nov 27, 2016 at 18:16 comment added Lucia @FanZheng: I see no reason for $K-1\ge n/m$. If half the $\kappa$s are very slightly more than average and half are very slightly less, then $K$ can be pretty close to $1$.
Nov 27, 2016 at 5:14 comment added Fan Zheng Looks like this is more combinatorial than it appears. Suppose there are m k's larger than average and n k's smaller than average. Then |J|>=m+n and K-1 >= n/m, so the coefficient in the inequality comes out as √(n/m).(m+n). By AM-GM (a special case of C-S!) This is at least √(m/n).2√(mn)=2n, which is what you get from the trivial bound.
S Nov 27, 2016 at 2:13 history suggested Botrance CC BY-SA 3.0
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Nov 27, 2016 at 1:46 comment added Lucia Look at $\widetilde{A} - \kappa A$ and then use Cauchy-Schwarz.
Nov 27, 2016 at 1:26 review Suggested edits
S Nov 27, 2016 at 2:13
Nov 27, 2016 at 1:18 review First posts
Nov 27, 2016 at 1:41
Nov 27, 2016 at 1:17 history asked user101672 CC BY-SA 3.0