Timeline for Normalizer of SL_2(Z) in GL_2(R)
Current License: CC BY-SA 3.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 1, 2020 at 4:15 | comment | added | LSpice | Should "the conditions that $a^2$, $b^2$, $c^2$, $d^2$, $ac$, $bd$ as necessary and sufficient" have the word "are integers" in it? | |
| Feb 21, 2014 at 10:55 | history | edited | Max Horn | CC BY-SA 3.0 |
Insert missing '='
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| Feb 21, 2014 at 8:41 | comment | added | Geoff Robinson | The two matrices given in the answer do not generate ${\rm SL}(2,\mathbb{Z}),$ even working up to scalar multiples. | |
| Feb 21, 2014 at 2:36 | comment | added | Igor Rivin | @SashaKolpakov you are correct, see the edit. | |
| Feb 21, 2014 at 2:36 | history | edited | Igor Rivin | CC BY-SA 3.0 |
fixed bugs.
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| Feb 21, 2014 at 1:49 | comment | added | math no more | The center of $GL_2(\mathbb{R})$ should be in every normalizer, so I'm not sure this can be true? | |
| Feb 21, 2014 at 1:17 | comment | added | Will Sawin | I presume he means $ad$ and $bc$. | |
| Feb 21, 2014 at 1:11 | comment | added | SashaKolpakov | Sorry, Igor, I don't understand why ac = xz\sqrt{st} should be an integer (do you mean it should? there is a part of the formula missing). | |
| Feb 21, 2014 at 0:56 | history | answered | Igor Rivin | CC BY-SA 3.0 |