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bio website gilkalai.wordpress.com
location Jerusalem
age 58
visits member for 4 years, 5 months
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Professor of Mathematics at the Hebrew University of Jerusalem and at Yale University

Dec
21
answered Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dec
21
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dear Vit, many thanks for your answer (which was certainly correct for more than a decade). I think it is a good and useful answer (while incorrect). Like in the case of Szemeredi's theorem an even simpler proof of Carleson's theorem is much desirable. In some sense, reasonable incorrect answers to the question can be as educating as correct ones. (And we do hope that most answers will become incorrect before they fit the 100-years twin MO question.)
Dec
21
awarded  Good Question
Dec
20
awarded  Notable Question
Dec
20
awarded  Popular Question
Dec
20
awarded  Nice Question
Dec
20
revised Examples of major theorems with very hard proofs that have NOT dramatically improved over time
deleted 151 characters in body
Dec
20
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dear Allen, This remarks referred to Endre's original proof. There are substantially simpler proofs available now. (But it would be great to have a proof that you can present in 4 hours, say.)
Dec
20
accepted Horst Knörrer's Permutation Cancellation Problem
Dec
20
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Also, arsmath, your question specifically referred to 100-years old or so theorems: "Are there results from a hundred years ago that have not appreciably simplified over the years? From the point of view of a modern mathematician, what is the hardest theorem proven a hundred years ago (or so)?"
Dec
20
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Be it as it may be, let's hope that my question will lead to a good list of answers. Generally speaking, in my opinion, duplicates (certainly with a gap of 3 years) that may lead to better answers (or just good new answers) are welcome.
Dec
20
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dear Victor, Yes
Dec
20
revised Examples of major theorems with very hard proofs that have NOT dramatically improved over time
added 532 characters in body
Dec
20
comment Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dear Arsmath, to a large extent the answers there were influenced by your specific question "I would like to believe that by 2110 the Langland's program would be reduced to a 10-page pamphlet (with complete proofs) that I could read over breakfast. Is this belief plausible?"
Dec
20
revised Examples of major theorems with very hard proofs that have NOT dramatically improved over time
added 316 characters in body; edited title
Dec
20
asked Examples of major theorems with very hard proofs that have NOT dramatically improved over time
Dec
11
awarded  Necromancer
Dec
11
awarded  Popular Question
Dec
11
revised Horst Knörrer's Permutation Cancellation Problem
added 1 characters in body
Dec
9
awarded  Nice Answer