The general-parameter Gaussian Laplace identity
Abstract
Original Mills normalization and complete classification.
Theorem 1.1 (General-parameter Gaussian convolution kernel identity).
Lean statement: D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_identity
Proof. Machine-checked in Lean as D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_identity (✓ std3). ∎
Source. Repository-derived.
Commentary.
For every real a and t, the source kernel G_a(t) equals t^3/4 times the integral from zero to one of (1+(2a-1)v^2) exp(-(1+v^2)t^2/4). Integrating the derivative of v exp(-(1+v^2)t^2/4) gives exp(-t^2/2) as the integral of (1-t^2 v^2/2) times the same exponential. Substitution in G and linearity of the integral give the stated identity. This is the source’s pointwise identity (2.3).
Theorem 1.2 (The negative-parameter Gaussian kernel is the original K kernel).
Lean statement: D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_eq_K
Proof. Machine-checked in Lean as D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_eq_K (✓ std3). ∎
Source. Repository-derived.
Commentary.
A second interval integration by parts gives G_(-1)(t)=K(t), preserving the original Gaussian convolution normalization and the exact K supplier.
Theorem 1.3 (The exact general-parameter Gaussian Laplace identity).
Lean statement: D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_laplace_identity
Proof. Machine-checked in Lean as D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_laplace_identity (✓ std3). ∎
Source. Repository-derived.
Commentary.
The original Mills Laplace formula and square convolution are combined with the original kernelLaplace identity at parameter -1. A direct integration by parts gives the t times Gaussian integral, and linearity in a then yields Y_(a,a-2)(x)-(a-1)=integral exp(-xt) G_a(t) for every x>0.
References
- Truth anchor:
D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_eq_K - Truth anchor:
D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_kernel_identity - Truth anchor:
D5/S3/Analytic/XuYangMillsRemainder/GaussianLaplace.gaussian_laplace_identity - Dependency: D5/S3/Analytic/XuYangMillsRemainder/Result