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Apr 18 at 3:25 history edited Tom Copeland CC BY-SA 4.0
Sign error corrected
Aug 27, 2023 at 11:10 comment added Tom Copeland On matched pairings, the Gaussian, and the CLT: Terence Tao's central limit theorem, Double Factorials (!!) and the Moment Method (youtube.com/watch?v=oPQ4mNcqY7k&t=665s) by Nica.
Feb 15, 2022 at 22:10 comment added Tom Copeland @MichaelHardy, I've done that for more important equations in other writings. Feel free to edit to your tastes as long as it doesn't change the content. I think I've invested quite a lot of time and effort on specifics in this answer to be forgiven for not going the whole ten yards on the formatting (28 taps vs. 4), and other unfinished notes beckon.
Feb 15, 2022 at 21:42 comment added Michael Hardy @TomCopeland : If you just google "latex symbols" you can see at once how to write $$\langle t-\langle t\rangle\rangle^2 $$ instead of $$<t-<t>>^2. $$
Feb 15, 2022 at 19:09 history edited Tom Copeland CC BY-SA 4.0
Intro / summary of assocations added
Feb 15, 2022 at 12:50 comment added Tom Copeland Ghys and Ranicki, in "Signatures in algebra, topology and dynamics", use the expression 'quadratic form' 51 times whereas 'Gaussian' is used only once in 'Gaussian elimination'. Functions, $f(z)$, are extremely important, of course, in mathematics also, but that doesn't explain the interpretation and utility of $e^{f(z)}$.
May 31, 2021 at 22:06 comment added Tom Copeland "Gaussian processes and Feynman diagrams" by William G. Faris, related to the general $Z = e^F$ (OEIX A036040) enumerating number of disconnected objects formed from connected ones, in this case a single graph with one edge with the exponential generating function $F = x^2/2$. The cumulant expansion formula A127671 (cf. A263634 for relation to the raising op for Appell polynomials) gives the inverse relation--connected from disconnected--mentioned in the answer.
May 31, 2021 at 18:14 comment added Tom Copeland More on the associations among the Heisenberg-Weyl algebra, matchings on simplices, and Gaussian distributions soon to come at oeis.org/A344678.
May 30, 2021 at 18:18 history edited Tom Copeland CC BY-SA 4.0
Introduced a combinatorial perspective
May 23, 2021 at 17:21 comment added Tom Copeland For more on the heat/diffusion equation, small oscillations, and quadratic relations, see Arnold's "Lectures on Partial Differential Equations."
May 23, 2021 at 2:08 comment added Tom Copeland For a discussion of integral transforms with general quadratic equations in an exponential, see "On self-reciprocal functions under a class of integral transforms" by Kurt Bernardo Wolf.
May 19, 2021 at 1:48 history edited Tom Copeland CC BY-SA 4.0
Corrected variable
May 17, 2021 at 19:54 comment added Tom Copeland See also "On Riemann's zeta function" by Bump and Ng (eudml.org/doc/173728) and the closely related "Binomial Polynomials Mimicking Riemann’s Zeta Function" by Coffey and Lettington (arxiv.org/pdf/1703.09251.pdf).
May 15, 2021 at 0:30 history edited Tom Copeland CC BY-SA 4.0
Added generalization
May 15, 2021 at 0:23 history edited Tom Copeland CC BY-SA 4.0
Added generalization
Apr 9, 2021 at 3:13 history edited Tom Copeland CC BY-SA 4.0
Misplaced t removed.
Apr 8, 2021 at 13:02 comment added Tom Copeland Related: Gauss-Markov theorem.
Apr 1, 2021 at 11:35 comment added Tom Copeland See also the Gauss-Weierstrass operator/transform en.m.wikipedia.org/wiki/Weierstrass_transform
Mar 16, 2021 at 23:01 comment added Tom Copeland Some researchers are exploring extended Heisenberg algebras and categories, such as Khovanov in "Heisenberg algebra and a graphical calculus" (arxiv.org/abs/1009.3295) and Brunden, Savage, and Webster (arxiv.org/abs/2007.01642). For more Hermite integrals and uniqueness of the Hermite polynomials as the only orthogonal Appell family, see Anshelevich see-math.math.tamu.edu/~manshel/papers/Hermite-integrals.pdf.
Mar 14, 2021 at 20:57 history edited Tom Copeland CC BY-SA 4.0
Changed to more accessible link (with additional interesting articles by Hersh).
Mar 1, 2021 at 21:26 comment added Tom Copeland See also "Adelic harmonic oscillator" by Branko Dragovicha arxiv.org/abs/hep-th/0404160
Feb 28, 2021 at 19:15 comment added Tom Copeland On relation to the Heisenberg uncertainty relation, see this Oxford lecture m.youtube.com/watch?v=cz0-HcAtU5U
Feb 26, 2021 at 7:32 history edited Tom Copeland CC BY-SA 4.0
Corrected variable and a link
Feb 25, 2021 at 19:13 history edited Tom Copeland CC BY-SA 4.0
Revamped
Feb 14, 2021 at 17:36 comment added Tom Copeland In another MO-Q Nik Weaver alludes to "Quantum Mechanics in Rigged Hilbert Space Language" by Rafael de la Madrid Modino--a good intro to the Hermite polynomials and the quantum harmonic oscillator and various spaces associated with them.
Feb 12, 2021 at 1:01 comment added Tom Copeland @AbdelmalekAbdesselam, link to your notes? I found "Hermite expansions of some tempered distributions" by Chihara et al., which refs Simon and also Kagawa. Expansion of tempered distributions works as well for the Laguerre polynomials (see mathoverflow.net/questions/382735/…) and should also for similar orthogonal polynomial sequences.
Feb 12, 2021 at 0:40 history edited Tom Copeland CC BY-SA 4.0
Added the classic Cartier paper
Feb 12, 2021 at 0:17 comment added Tom Copeland @AbdelmalekAbdesselam, thanks. Bet you can find the germ of the idea in the convolutional soln. to the Cauchy problem mentioned above as you can for the Schwartz distributions in 19th century classic potential theory as sketched in mathoverflow.net/questions/127601/…. Sato runs with this. Would be interesting to find a good monograph comparing, contrasting the theories and elucidating the historical connections.
Feb 11, 2021 at 23:43 comment added Abdelmalek Abdesselam BTW, Treves in his book on distributions does not mention this. Other authors credit Reed-Simon, but this was well known to Schwartz and Grothendieck (mentioned in Schwartz's book on distributions and A.G. in his thesis in Memoirs of AMS). I don't know who first discovered the result. Wiener?
Feb 11, 2021 at 23:37 comment added Abdelmalek Abdesselam Don't know about nascent delta. For the Schauder basis, I have some notes from a course I taught. Otherwise there is aip.scitation.org/doi/abs/10.1063/… but not well written, it's also in Reed Simon Vol 1, not better, most of the proof punted in the exercises. Simon's new book on analysis is much better.
Feb 11, 2021 at 23:29 comment added Tom Copeland @AbdelmalekAbdesselam, refs? Connected to the use of the Gaussian as a nascent Dirac delta and the Cauchy problem, similar to Sato's theory of hyperfunctions?
Feb 11, 2021 at 22:49 comment added Abdelmalek Abdesselam Also good to know: the Hermite functions give a Schauder basis for the Schwartz space $\mathscr{S}(\mathbb{R})$ and therefore, and more importantly, also for the space of tempered distributions $\mathscr{S}'(\mathbb{R})$. They essentially trivialize lots (but not all) of functional analytic questions about these spaces.
Feb 11, 2021 at 20:18 history edited Tom Copeland CC BY-SA 4.0
Provided links, another ref to CM systems
Feb 8, 2021 at 21:29 history edited Tom Copeland CC BY-SA 4.0
Defined D
Feb 8, 2021 at 2:27 history answered Tom Copeland CC BY-SA 4.0