Timeline for The $2\pi$ in the definition of the Fourier transform
Current License: CC BY-SA 3.0
22 events
| when toggle format | what | by | license | comment | |
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| Mar 31, 2017 at 22:08 | review | Close votes | |||
| Apr 1, 2017 at 1:01 | |||||
| Mar 31, 2017 at 10:36 | answer | added | Rajesh D | timeline score: 1 | |
| Mar 29, 2017 at 17:15 | history | edited | coudy | CC BY-SA 3.0 |
added reference to Folland.
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| Mar 24, 2017 at 11:59 | vote | accept | coudy | ||
| Mar 23, 2017 at 19:49 | comment | added | LSpice | (Err, of course I meant to normalise the sum by the square root of the cardinality of $\mathfrak f$.) | |
| Mar 23, 2017 at 18:15 | comment | added | LSpice | @MichaelRenardy, problem 2 is of course subsumed in the bigger question, which one is $+i$ and which one is $-i$? (This question drove me batty when trying to make sense of the question: what is the value of $\sum_{t \in \mathfrak f} \zeta(t^2)$ when $\zeta$ is a non-trivial, complex character of the finite field $\mathfrak f$, and the cardinality of $\mathfrak f$ is $3$ modulo $4$? Namely, is it $+i$ or $-i$, and what does it mean to ask?) | |
| Mar 23, 2017 at 17:24 | comment | added | Michael Renardy | There are three major unsolved problems in mathematics: 1. Where to put to $2\pi$ in the Fourier transform, 2. Whether the exponent in the Fourier transform should have the $+i$ or the $-i$, 3. Which factor in the inner product gets the complex conjugate. | |
| Mar 23, 2017 at 16:46 | comment | added | Piero D'Ancona | This joke is actually written in print, in some notes by L.Nirenberg | |
| Mar 23, 2017 at 16:30 | answer | added | Ben McKay | timeline score: 6 | |
| Mar 23, 2017 at 15:50 | answer | added | Dirk | timeline score: 6 | |
| Mar 23, 2017 at 14:58 | comment | added | Neal | I'm reminded of an anecdote I heard from a professor. When this professor was a graduate student, on the first day of his first Fourier analysis class, the professor walked in, went straight to the chalkboard, and wrote: "$2\pi = \frac{1}{2\pi} = 1$." | |
| Mar 23, 2017 at 14:51 | comment | added | nfdc23 | So is the warning about the 2nd convention by Katznelson that the associated self-duality of $\mathbf{R}$ has too many good properties (as described in many ways below)? | |
| Mar 23, 2017 at 14:27 | answer | added | WhatsUp | timeline score: 25 | |
| Mar 23, 2017 at 14:25 | answer | added | Abdelmalek Abdesselam | timeline score: 6 | |
| Mar 23, 2017 at 12:29 | history | edited | coudy | CC BY-SA 3.0 |
add Treves in the list.
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| Mar 23, 2017 at 7:49 | answer | added | yuggib | timeline score: 26 | |
| Mar 23, 2017 at 4:57 | answer | added | clyde | timeline score: 3 | |
| Mar 23, 2017 at 3:00 | answer | added | Alexandre Eremenko | timeline score: 4 | |
| Mar 23, 2017 at 1:21 | comment | added | lcv | The conventions reflects different interpolations between simplicity and the wish of making the Fourier transform a unitary operator. Is there more? | |
| Mar 23, 2017 at 0:03 | comment | added | Theo Johnson-Freyd | I am strongly reminded of the opening story from Wigner's Unreasonable Effectiveness. | |
| Mar 22, 2017 at 22:32 | comment | added | Gerald Edgar | Perhaps questions about history would fit better in hsm.stackexchange.com | |
| Mar 22, 2017 at 22:17 | history | asked | coudy | CC BY-SA 3.0 |