(************** Content-type: application/mathematica ************** CreatedBy='Mathematica 5.0' Mathematica-Compatible Notebook This notebook can be used with any Mathematica-compatible application, such as Mathematica, MathReader or Publicon. The data for the notebook starts with the line containing stars above. To get the notebook into a Mathematica-compatible application, do one of the following: * Save the data starting with the line of stars above into a file with a name ending in .nb, then open the file inside the application; * Copy the data starting with the line of stars above to the clipboard, then use the Paste menu command inside the application. Data for notebooks contains only printable 7-bit ASCII and can be sent directly in email or through ftp in text mode. Newlines can be CR, LF or CRLF (Unix, Macintosh or MS-DOS style). 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Fixed other variables. D = 12 \ \>", "Text"], Cell[CellGroupData[{ Cell[BoxData[ \(\(\(\[IndentingNewLine]\)\(GeneratingSum[10, \ 12, \ 0.5, \ 0.3]\[IndentingNewLine] GeneratingIntegral[10, \ 12, \ 0.5, \ 0.3]\)\)\)], "Input"], Cell[BoxData[ \(\(\(1024.0000000006082`\)\(\[InvisibleSpace]\)\) + 5.3870274039105206`*^-48\ \[ImaginaryI]\)], "Output"], Cell[BoxData[ \(337.9398107606481`\)], "Output"] }, Open ]], Cell["I see agreement is improving in large N.", "SmallText"], Cell[CellGroupData[{ Cell[BoxData[{ \(GeneratingSum[60, \ 12, \ 0.5, \ 0.3]\), "\[IndentingNewLine]", \(GeneratingIntegral[60, \ 12, \ 0.5, \ 0.3]\), "\[IndentingNewLine]", \(\)}], "Input"], Cell[BoxData[ \(1.171050460713214`*^18 - 0.09680571230488141`\ \[ImaginaryI]\)], "Output"], Cell[BoxData[ \(9.28364023575655`*^17\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[{ \(GeneratingSum[600, \ 12, \ 0.5, \ 0.3]\), "\[IndentingNewLine]", \(GeneratingIntegral[600, \ 12, \ 0.5, \ 0.3]\)}], "Input"], Cell[BoxData[ \(1.01296436104000673593847351`12.303046000383846*^181 - 3.5035447483788744396241205269`12.303046000383846*^163\ \ \[ImaginaryI]\)], "Output"], Cell[BoxData[ \(1.0129643523907122`*^181\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[{ \(GeneratingSum[600, \ 12, \ 0.5, \ 3]\), "\[IndentingNewLine]", \(GeneratingIntegral[600, \ 12, \ 0.5, \ 3]\)}], "Input"], Cell[BoxData[ \(1.36469266868107132496392`12.303046000383844*^179 - 1.0532537241882731887856522062`12.303046000383844*^163\ \ \[ImaginaryI]\)], "Output"], Cell[BoxData[ \(9.77679101855015`*^178\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[{ \(GeneratingSum[1200, \ 12, \ 0.5, \ 3]\), "\[IndentingNewLine]", \(GeneratingIntegral[1200, \ 12, \ 0.5, 3]\)}], "Input"], Cell[BoxData[ \(6.11185190816697742142843274832`11.932297057481106*^357 - 3.403244679181817653465498`11.932297057481106*^342\ \[ImaginaryI]\)], \ "Output"], Cell[BoxData[ \(5.28388484780692976821488847493`11.932317686183826*^357\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[{ \(GeneratingSum[8000000, \ 12, \ 0.5, \ 3]\), "\[IndentingNewLine]", \(GeneratingIntegral[8000000, \ 12, \ 0.5, \ 3]\)}], "Input"], Cell[BoxData[ \(\(-5.98479949165585253`7.483685545588577*^2408238\) + 0``-2408230.9153634966\ \[ImaginaryI]\)], "Output"], Cell[BoxData[ \(1.07304165267541395014116`7.716283714026401*^2381099\)], "Output"] }, Open ]], Cell["\<\ At this size, the agreement is off by many, many orders of magnitude. I \ wonder if the convergence is sufficiently fast based on that, or if I must \ include the Bernoulli numbers. \ \>", "Text"] }, Open ]], Cell[CellGroupData[{ Cell["\<\ Part 2--Evaluate Integral \ \>", "Subsection"], Cell[CellGroupData[{ Cell[BoxData[ \(IntegralResult[\[Alpha]_, \ Num_, \ Dst_]\ = \ \(1\/\(2\ \[Pi]\)\) \(\[Integral]\_\(-\[Pi]\)\%\[Pi] Log[\(\((\[Alpha]\ Num)\)\^\(\(-2\)\ \[Alpha]\ Num\)\) \ \(Num\^Num\) \(\[ExponentialE]\^\(\(-\ \[Lambda]\^2\)\/\(\(\ \)\(4 \ \((Dst\^2\/\(\[Alpha]\ Num\))\)\)\)\)\) \@\(\[Pi]\/\((Dst\^2\/\(\[Alpha]\ Num\ \))\)\)] \[DifferentialD]\[Lambda]\)\)], "Input"], Cell[BoxData[ \(\(\(Num\ \[Pi]\^3\ \[Alpha]\)\/\(3\ Dst\^2\) + \[Pi]\ Log[\[Pi]] + 2\ \ \[Pi]\ Log[\[ExponentialE]\^\(-\(\(Num\ \[Pi]\^2\ \[Alpha]\)\/\(4\ Dst\^2\)\)\ \)\ Num\^Num\ \((Num\ \[Alpha])\)\^\(\(-2\)\ Num\ \[Alpha]\)\ \@\(\(Num\ \ \[Alpha]\)\/Dst\^2\)]\)\/\(2\ \[Pi]\)\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[ \(\(\(\[IndentingNewLine]\)\(IntegralResult[0.5, \ 100, \ 10]\)\)\)], "Input"], Cell[BoxData[ \(69.1292758919272`\)], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[{ \(Clear[Num, \ Dst]\), "\[IndentingNewLine]", \(Apart[ Limit[\(1\/\(\(Num\)\(\ \)\(Dst\)\(\ \)\)\) IntegralResult[1\/2, \ Num, \ Dst], \ Num\ \[Rule] \ \[Infinity]]\ ]\)}], "Input"], Cell[BoxData[ \(\(-\(\[Pi]\^2\/\(24\ Dst\^3\)\)\) + Log[4]\/\(2\ Dst\)\)], "Output"] }, Open ]], Cell["\<\ At this point, nothing else really needs to be said--this is the result we \ were looking for. I wonder what additional corrections can be gleaned from \ the Bernoulli numbers.\ \>", "Text"] }, Open ]], Cell[CellGroupData[{ Cell["Part 3--Higher order corrections?", "Subsection"], Cell["\<\ The first step would be to determine in what approximation I lost the \ higher-order corrections. These are speculated on in the accompanying \ progress report. I believe that simply taking another element in the \ expansion of the logarithms will be sufficient for higher-order terms.\ \>", "Text"], Cell[CellGroupData[{ Cell[BoxData[ \(\(\(\[IndentingNewLine]\)\(Simplify[ Series[\((1\ + \ x)\)\ Log[1\ + \ x]\ + \ \((1\ - \ x)\)\ Log[ 1\ - \ x], \ {x, \ 0, \ 8}]]\)\)\)], "Input"], Cell[BoxData[ InterpretationBox[ RowBox[{\(x\^2\), "+", \(x\^4\/6\), "+", \(x\^6\/15\), "+", \(x\^8\/28\), "+", InterpretationBox[\(O[x]\^9\), SeriesData[ x, 0, {}, 2, 9, 1], Editable->False]}], SeriesData[ x, 0, {1, 0, Rational[ 1, 6], 0, Rational[ 1, 15], 0, Rational[ 1, 28]}, 2, 9, 1], Editable->False]], "Output"] }, Open ]], Cell[CellGroupData[{ Cell[BoxData[ \(\[Integral]\_\(-\[Infinity]\)\%\[Infinity]\( \[ExponentialE]\^\(\(-a\) \ \((b\ x)\)\^2\)\) \(\[ExponentialE]\^\(\(-\[ImaginaryI]\)\ x\ \[Lambda]\)\) \ \[DifferentialD]x\)], "Input"], Cell[BoxData[ \(If[Re[a\ b\^2] > 0, \(\[ExponentialE]\^\(-\(\[Lambda]\^2\/\(4\ a\ b\^2\)\)\)\ \ \@\[Pi]\)\/\@\(a\ b\^2\), Integrate[\[ExponentialE]\^\(\(-x\)\ \((a\ b\^2\ x + \[ImaginaryI]\ \ \[Lambda])\)\), {x, \(-\[Infinity]\), \[Infinity]}, Assumptions \[Rule] Re[a\ b\^2] \[LessEqual] 0]]\)], "Output"] }, Open ]], Cell["\<\ The Fourier transform of the pair of these, however, is more difficult.\ \>", "Text"], Cell[CellGroupData[{ Cell[BoxData[ \(\[Integral]\_\(-\[Infinity]\)\%\[Infinity]\( \[ExponentialE]\^\(\(-a\) \ \((b\ x)\)\^2\)\) \(\[ExponentialE]\^\(\(-a\) \((b\ x)\)\^4\)\) \(\ \[ExponentialE]\^\(\(-\[ImaginaryI]\)\ x\ \[Lambda]\)\) \[DifferentialD]x\)], \ "Input"], Cell[BoxData[ \(\[Integral]\_\(-\[Infinity]\)\%\[Infinity]\( \[ExponentialE]\^\(\(-a\)\ \ b\^2\ x\^2 - a\ b\^4\ x\^4 - \[ImaginaryI]\ x\ \[Lambda]\)\) \ \[DifferentialD]x\)], "Output"] }, Open ]], Cell["\<\ So the issue seems to be that the integral for higher-order terms is more \ difficult. In fact, taking one of these exponentials alone returns me to the \ hypergeometric functions!: \ \>", "Text"], Cell[CellGroupData[{ Cell[BoxData[ \(\[Integral]\_\(-\[Infinity]\)\%\[Infinity]\( \[ExponentialE]\^\(\(-a\) \ \((b\ x)\)\^4\)\) \(\[ExponentialE]\^\(\(-\[ImaginaryI]\)\ x\ \[Lambda]\)\) \ \[DifferentialD]x\)], "Input"], Cell[BoxData[ \(If[Re[a\ b\^4] > 0 && Im[\[Lambda]] < 0, \(\[ImaginaryI]\ \((\(-32\)\ \((\[Lambda]\^4\/\(a\ \ b\^4\))\)\^\(1/4\)\ Gamma[5\/4]\ HypergeometricPFQ[{}, {1\/2, 3\/4}, \ \[Lambda]\^4\/\(256\ a\ b\^4\)] + \((\[Lambda]\^4\/\(a\ b\^4\))\)\^\(3/4\)\ \ Gamma[\(-\(1\/4\)\)]\ HypergeometricPFQ[{}, {5\/4, 3\/2}, \[Lambda]\^4\/\(256\ \ a\ b\^4\)])\)\)\/\(16\ \[Lambda]\), Integrate[\[ExponentialE]\^\(\(-a\)\ b\^4\ x\^4 - \[ImaginaryI]\ x\ \ \[Lambda]\), {x, \(-\[Infinity]\), \[Infinity]}, Assumptions \[Rule] Im[\[Lambda]] \[GreaterEqual] 0 || Re[a\ b\^4] \[LessEqual] 0]]\)], "Output"] }, Open ]] }, Open ]] }, FrontEndVersion->"5.0 for Microsoft Windows", ScreenRectangle->{{0, 1600}, {0, 1127}}, WindowSize->{1388, 1073}, WindowMargins->{{52, Automatic}, {Automatic, -30}} ] (******************************************************************* Cached data follows. 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