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Xiaolei Wu's user avatar
Xiaolei Wu
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 Nice Question
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Kernel of linear representation of Baumslag-Solitar group
I will rule out those cases also. Thank you, Anton
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Kernel of linear representation of Baumslag-Solitar group
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Kernel of linear representation of Baumslag-Solitar group
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Kernel of linear representation of Baumslag-Solitar group
Anton, you are right. I will edit the question to rule out those cases.
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Kernel of linear representation of Baumslag-Solitar group
Hi, Anton Klyachko. Your answer is contained in my second observation.
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Kernel of linear representation of Baumslag-Solitar group
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Kernel of linear representation of Baumslag-Solitar group
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Can the order of a rational number in Z/pZ be as large as we want
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Can the order of a rational number in Z/pZ be as large as we want
Thank you, Douglas Zare. I see your proof now. I think I am going to close this question soon since it is actually very easy.
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Can the order of a rational number in Z/pZ be as large as we want
Hi, Felipe. I actually think you are wrong now. There are always elements in Z/pZ has order 2 since the multiplicative group has order p-1 which is an even number if p is odd.
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Can the order of a rational number in Z/pZ be as large as we want
Hi, Felipe, how do you see the order is at least logp/log2? I am not a number theorist, so I might be a little slow on this.
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Can the order of a rational number in Z/pZ be as large as we want
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Can the order of a rational number in Z/pZ be as large as we want
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Non trivial vector bundle over non-paracompact contractible space
David White, You are write. I was wrong.
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Non trivial vector bundle over non-paracompact contractible space
You can always use a nontrivial bundle over a sphere one point join with a trivial bundle over a space satisfying those properties to construct such example.
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Exact 1- and 2-forms in $R^n$
@Alan, you can say every closed loop is contractible, which is the same as simply connected.
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Any method to detect subgroup generated by a subset of the generators from its presentation
Agol, Can you tell me why when it is a HNN extension, the answer should be yes? As a matter of fact, my group arise from some topology construction, if I calculated the fundamental group right, it is an HNN extension.
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Any method to detect subgroup generated by a subset of the generators from its presentation
Hi, Mosher, I want to know what the subgroup is or can you find a presentation of this group.
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Any method to detect subgroup generated by a subset of the generators from its presentation
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