![]() |
| If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|||||||
| Tags: derivatives, distribution, gaussian, generalized, little, math, multiple, physics, puzzle, seeking |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
|
I have been trying to find a generalized expression for the multiple
derivatives of a Gaussian. Gaussian functions of course have many application in physics and math, and high order derivatives of this Gaussian typically are involved in generating Green functions. I posted this "puzzle" at the link below along with some hints. http://jayryablon.files.wordpress.co.../02/puzzle.pdf It seems to me that there should be a way to do this, and that there should be a general technique for this sort of thing, besides guesswork and pattern matching, by using the series expansion. Can anyone solve this, obtaining a generalized expression for any order of derivative? Thanks, Jay ____________________________ Jay R. Yablon Email: co-moderator: sci.physics.foundations Weblog: http://jayryablon.wordpress.com/ Web Site: http://home.roadrunner.com/~jry/FermionMass.htm |
| Ads |
|
#2
|
|||
|
|||
|
Jay R. Yablon wrote:
[...] Can anyone solve this, obtaining a generalized expression for any order of derivative? Yeah, exactly as you've done. Slap the term with an arbitrary derivative, and carry through the math. The cyclical nature of exp() promises a return of the function, which you can already see in the x^2j component. Substitute i = 2j - d, pull the x^d terms out of the summation if you can, and hope there's a double factorial identity that will help. Thanks, Jay ____________________________ Jay R. Yablon Email: co-moderator: sci.physics.foundations Weblog: http://jayryablon.wordpress.com/ Web Site: http://home.roadrunner.com/~jry/FermionMass.htm |
|
#3
|
|||
|
|||
|
On Feb 7, 10:41 pm, "Jay R. Yablon" wrote:
I have been trying to find a generalized expression for the multiple derivatives of a Gaussian. Gaussian functions of course have many application in physics and math, and high order derivatives of this Gaussian typically are involved in generating Green functions. I posted this "puzzle" at the link below along with some hints. http://jayryablon.files.wordpress.co.../02/puzzle.pdf It seems to me that there should be a way to do this, and that there should be a general technique for this sort of thing, besides guesswork and pattern matching, by using the series expansion. Can anyone solve this, obtaining a generalized expression for any order of derivative? Thanks, Jay ____________________________ Jay R. Yablon Email: co-moderator: sci.physics.foundations Weblog:http://jayryablon.wordpress.com/ Web Site:http://home.roadrunner.com/~jry/FermionMass.htm Yoour puzzle has no solution. Let's make the problem a little simpler, assume A/2=1, so, you are being asked to find the n-th derivative of exp(x^2) df/dx=2x*exp(x^2) Let's assume that: (d^n)f/df^n=P(x)*exp(x^2) where P(x) is a plynimial in x Then, the derivative of order n+1 is: d^(n+1)f/df^(n+1)=(2xP(x)+P'(x))*exp(x^2) There is no real correlation between the n-th and the n-th+1 derivatives. |
|
#4
|
|||
|
|||
|
Jay R. Yablon schrieb:
I have been trying to find a generalized expression for the multiple derivatives of a Gaussian. Gaussian functions of course have many application in physics and math, and high order derivatives of this Gaussian typically are involved in generating Green functions. I posted this "puzzle" at the link below along with some hints. http://jayryablon.files.wordpress.co.../02/puzzle.pdf It seems to me that there should be a way to do this, and that there should be a general technique for this sort of thing, besides guesswork and pattern matching, by using the series expansion. Can anyone solve this, obtaining a generalized expression for any order of derivative? Thanks, Jay ____________________________ Jay R. Yablon Email: co-moderator: sci.physics.foundations Weblog: http://jayryablon.wordpress.com/ Web Site: http://home.roadrunner.com/~jry/FermionMass.htm http://en.wikipedia.org/wiki/Hermite_polynomials Ciao Karl |
|
#5
|
|||
|
|||
|
"karl" wrote in message ... Jay R. Yablon schrieb: I have been trying to find a generalized expression for the multiple derivatives of a Gaussian. Gaussian functions of course have many application in physics and math, and high order derivatives of this Gaussian typically are involved in generating Green functions. I posted this "puzzle" at the link below along with some hints. http://jayryablon.files.wordpress.co.../02/puzzle.pdf It seems to me that there should be a way to do this, and that there should be a general technique for this sort of thing, besides guesswork and pattern matching, by using the series expansion. Can anyone solve this, obtaining a generalized expression for any order of derivative? Thanks, Jay ____________________________ Jay R. Yablon Email: co-moderator: sci.physics.foundations Weblog: http://jayryablon.wordpress.com/ Web Site: http://home.roadrunner.com/~jry/FermionMass.htm http://en.wikipedia.org/wiki/Hermite_polynomials Ciao Karl Thank you Karl, that was most helpful. Jay |
|
#6
|
|||
|
|||
|
On Mon, 08 Feb 2010 09:14:42 +0100, karl
wrote: http://en.wikipedia.org/wiki/Hermite_polynomials Ciao Karl [Hammond] I'll be a sonofagun! So THATS where the famous Hermite Polynomials come from! Leave it to Jay to discover a new derivation? Thanks Karl for keeping your eyes open! |
|
#7
|
|||
|
|||
|
Hi Jay et al.
On Feb 8, 11:29 am, "Jay R. Yablon" wrote: Thanks to Hans Devries and Karl, I have the answer. It is the Gaussian Hermite series shown in the file below. Jay http://jayryablon.files.wordpress.co...2/puzzle-2.pdf Refering the final equation. 1) We should expect exp(1/2 A x^2) to be dimensionless and thus a scalar that can be divided out on each side, that sends us to a general field. 2) A thought is to convert the factorials to Gamma's to make a continuous function. The hard Sigma really cannot exist in a single particle system, because there is no way to define "x". "x" needs relativity. 3) After (1) a (d/dx)^n operator floats, that may become more physical using (d'dx^u)^n to enable spacetime. (u=1,2,3,4). 4) At this point the Sigma operator obtains control due to the relativity of a 2 particle system. 5) The Hermites are all field, what you want is a couple inter-action, that way you can get spin and system energy. I (we) dabble a bit in couples, http://physics.trak4.com/GR_Charge_Couple.pdf 6) We should expect two interacting particle fields to output radiation and have gravitational and electrical interaction. (That #(6) sounds darn sexy on 2nd read :-). That was fun. Regards Ken S. Tucker |
|
#8
|
|||
|
|||
|
On Feb 9, 12:13 am, "Ken S. Tucker" wrote:
Hi Jay et al. On Feb 8, 11:29 am, "Jay R. Yablon" wrote: Thanks to Hans Devries and Karl, I have the answer. It is the Gaussian Hermite series shown in the file below. Jay http://jayryablon.files.wordpress.co...2/puzzle-2.pdf Refering the final equation. 1) We should expect exp(1/2 A x^2) to be dimensionless and thus a scalar that can be divided out on each side, that sends us to a general field. 2) A thought is to convert the factorials to Gamma's to make a continuous function. The hard Sigma really cannot exist in a single particle system, because there is no way to define "x". "x" needs relativity. 3) After (1) a (d/dx)^n operator floats, that may become more physical using (d'dx^u)^n to enable spacetime. (u=1,2,3,4). 4) At this point the Sigma operator obtains control due to the relativity of a 2 particle system. 5) The Hermites are all field, what you want is a couple inter-action, that way you can get spin and system energy. I (we) dabble a bit in couples,http://physics.trak4.com/GR_Charge_Couple.pdf 6) We should expect two interacting particle fields to output radiation and have gravitational and electrical interaction. (That #(6) sounds darn sexy on 2nd read :-). That was fun. Regards Ken S. Tucker On Feb 9, 5:47 pm, eric gisse wrote: Ken S. Tucker wrote: [...] Thanks for the timely demonstration ... If there was a Nobel Prize for stupidity, Gisse would be front runner. I think Jay has a chance at ascendancy, two is the hardest number, it requires a leap to couple, and the relativity involved in that, furthermore think Jay may create an infinite set of solutions to the coupled EFE's, but gets fixed to a quantized relativity. Ken |
|
#9
|
|||
|
|||
|
Ken S. Tucker wrote:
[...] Thanks for the timely and *repeated* demonstration of the Dunning-Kruger effect, Ken. |
| Thread Tools | |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Quantum Gravity 156.1: More Re Generalized P and P ' PI Via Generalized-Modified Uniform Distribution Weighting | OsherD | Physics - General Discussion | 0 | June 19th 07 07:29 AM |
| Quantum Gravity 156.0: Generalized P and P ' PI Via Generalized-Modified Uniform Distribution Weighting | OsherD | Physics - General Discussion | 0 | June 17th 07 08:50 AM |
| Derivative Products of Form (df/dx)(dg/dx) in Physics 6: Bivariate Normal/Gaussian Distribution | OsherD | Physics - General Discussion | 2 | January 10th 06 03:54 PM |
| Derivative Products of Form (df/dx)(dg/dx) in Physics 6: Bivariate Normal/Gaussian Distribution | OsherD | Physics - General Discussion | 0 | January 7th 06 07:58 AM |
| Normalizing Gaussian Derivatives | ip4ram@yahoo.com | Mathematical Research (Moderated) | 1 | May 7th 04 10:35 AM |