elements of gamma, bessel and zeta function theory 1...

23
1 Elements of Gamma, Bessel and Zeta function theory 1. Definitions The reference to the below are modified Bessel-Hankel functions ) ( / ) ( arctan : ) ( x J x Y x and 2 ) 1 ( 2 2 2 ) ( 2 ) ( ) ( 2 : ) 2 ( x H x Y x J x , which are linked by the relation x dx d x ) 2 ( 4 1 2 . The functions are used to define and investigate the function ) 1 ( 1 ) 2 ( ) 2 ( 1 : ) ( 2 2 2 2 x x x x x x for 1 ) 2 Re( 1 and 0 ) 2 Re( s with its Mellin transform ) 2 ( ) 2 ( ) 2 ( 2 cos 2 2 cos 2 ) ( 2 0 2 2 2 / 1 s s s s d x x s s .

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Page 1: Elements of Gamma, Bessel and Zeta function theory 1 ...fuchs-braun.com/media/17a5b4ad5552bbd8ffff8076fffffff2.pdf2 2. Gamma function theory An equivalent formulation to Jacobi’s

1

Elements of Gamma, Bessel and Zeta function theory

1. Definitions

The reference to the below are modified Bessel-Hankel functions

)(/)(arctan:)( xJxYx

and

2)1(22

2 )(2)()(2:)2( xHxYxJx ,

which are linked by the relation

x

dxdx )2(

4

12

.

The functions are used to define and investigate the function

)1

(1

)2

()2(1

:)( 2222xxx

xx

x

for 1)2Re(1 and 0)2Re( s with its Mellin transform

)2

()2

()2

(

2cos

22

cos

2)(2

0

22

2/1

sss

s

dxx ss .

Page 2: Elements of Gamma, Bessel and Zeta function theory 1 ...fuchs-braun.com/media/17a5b4ad5552bbd8ffff8076fffffff2.pdf2 2. Gamma function theory An equivalent formulation to Jacobi’s

2

2. Gamma function theory

An equivalent formulation to Jacobi’s theta function for

1

2

)( xnex (see [12] H.

Hamburger, [13] N. Nielsen, chapter 13, §71) is the series

(2.1)

122

1

2 12121cot

nx

x

xexii nx

It further holds (see [13] N. Nielsen, chapter 1,11,13, §4, 60, 68, 71, 73, [1] B. C. Berndt,

chapter 6, example 2, chapter 8, entry 4/5/17(v))

(2.2) x

dx

x

xx

x

x

x

xx

ss

1

0

1

1)(

)(

)1(

)1(cot for 1)Re(0 s

(2.3) and with

)111

)1(

)1(

1 xnnnx

x

xn

(2.4) )21(1

2sin2)1

1

1cot

122

2

11

nx

x

xkx

xnxnx

.

The symmetric Beta function (see [13] N. Nielsen, chapter 11, §60, chapter X, §53)

(2.5) x

dx

x

x

x

dx

x

xx

sssB

sss

0

1

0

1

11sin)1,(

for 1)Re(0 s

with its relations to [25] E. C. Titchmarsh, 2.11)

(2.6)

x

dx

x

x

s

s s

0

2)1(sin

)1(

for 1)Re(0 s

plays a key role in the Mellin’s inverse theorem, with its relation to Ramanujan series ([1] B.

C. Berndt, chapter 4 ff.) in the form

(2.7) x

dxnxxs

s

ns

1

0 0

)()()(sin

and its link to the Zeta function

(see [8] H.M. Edwards 10.10) representations (integration by

parts ss xsxdx

d )1()( 1 )

0

1

2

2 1

)1(

)1()(

sin

)1(dxx

xx

x

dx

ds

s

s s

,

1)Re(0 s

0

1

)1(

)1(log)(

sin x

dxx

x

xx

dx

ds

s

s

, 1)Re(0 s

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3

and its relation to Ramanujan’s infinite series analysis in the form

(2.8)

0

1

0

))(1(log)(sin x

dxxxnxs

s

sn

, 1)Re(0 s ,

leading to the functional equation in the form ([25] E. C. Titchmarsh, 2.9)

)1()1()2()(

2sin

sss

s

s

.

Remark From [13] N. Nielsen, chapter 13, 14 § 68, 78) we recall

1

00

)(logsinlog2

1)

2(log)

2

1(log)

2,

2

1(

2

1log dxxxdx

ssssB

0

32

)1(2

1log)

2,

2

1(

2

1log dt

et

eeeesB

t

txttt

as starting point for Kummer’s series representation of

1

)2sin(log

sinlog2

1log)1()2log)(

2

1()(log nx

n

nxxxx

.

Asymptotically it holds (see [8] H.M. Edwards 10.10, [13] N. Nielsen, chapter 13, §73, [25] E.

C. Titchmarsh, 2.15.8)

0log2

1

log)1(loglog1

)(

)(log

)1(

)1(

x

x

xxxxx

xx

xx

x

x .

1

0

1

1

1

)(

)()(glo dt

t

t

x

xx

x

With reference to (1.20) we further mention (see [13] N. Nielsen, chapter 9, §51)

x

dx

x

xxs

ss

1

0

1

1cot

for 1)Re(0 s

x

dx

x

xx

s

s ss

1

0

1

log1log for 1)Re(0 s

x

dxxxarc

ss

s

1

0

)cot(

2cos

for 1)Re(0 s

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4

x

dxx

xss

s)1

1log(

2sin

2

1

0

for 2)Re(0 s

xx

dx

x

xxs

ss

log1)

2tan(log

1

0

1

p. 153

1

1

0

2/31 )2cos(2log

log)1(

2)sin(log

n

ns

t

dt

tt

xxxs

ss

10 s

1

)cos()

2sin(2log

n

nss

see [13] N. Nielsen, Integrallogarithmus, chapter 1, §7 .

Using the abbreviation

(2.9) )()1(:)( xfxfxf

n

nsss

n

s

........*2*1

))....(2)(1(:

1

, 1:

0

1

s

we recall Mellin’s inverse formula from [13] N. Nielsen, chapter 9, §45-53, chapter 16, §86-

92, with its relation to Ramanujan’s Master Theorem ([1] B. C. Berndt, The first quarterly

report, 1.2 Theorem I (Ramanujan’s Master Theorem) and Theorem (Hardy)) in the form

)()()( 1

0

nndxxxF n

for kxk

kxF )(

!

)()(

0

in the neighborhood of 0x .

Lemma 2.1 (Mellin inverse formula):

For a function

(2.10)

0

1)1(:)(

n

sWsW n for 0)Re( s

fulfilling 0)(

lim kn

nW for n

the following series define analytical functions for 2/1)Re( s resp. 2/1)Re( s

(2.11)

0

)1()1(:)( nnn xWsf

and

0

)1()1(:)( nn xnWsg .

If )(sW can be represented in the form

1

0

1)()( dxxxsW s it further holds

(2.12)

1

0)1(1

)()(

sx

dxxsf

and

1

01

)()(

xs

dxxsg

,

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5

whereby both functions (1.28) are analytical (probably with the exception on the x-axis for

1x resp. 1x ). With respect to (1.27) it further holds (with variable substitution

t

tx

x

xt

11)

dxxx

gx

dtxt

tf

x

dx

x

xxsW

s

st

s

s1

0

1

0

1

0

)1

(1

1

)1

1(

)1(

)1()(

sin

for

1)Re(0 s

(2.13) dsxs

sW

ix

xf

xg

x

ia

ia

s

sin

)(

2

1

1

)1

1(

)1

(1

for

10 a and )( with iexx

Corollary 2.2 For

0

))(2

1(:)( nxnxg it holds

(2.14)

0 0

1)()1

(1

)2

1(

sin x

dxxxg

x

dxx

xg

xs

s

ss

and it holds ?)(0

divergentdttg

and dtxtt

x

0

22)(sinh

1

sinh

12)(

)

(2.15) x

dxdttg

xnxgxs

ss s

010

1 )(1

)()2

1(

sin)1(

Remark 2.3 From [26] G.N. Watson 13-2 we recall

(2.16) x

dxebxJx

ba

sbax

s

s

s

s

)(

)(

)2

1()2(

1

02

1

22

1

From (2.16) it follows

i) x

dxexJxs x

s

s

)(2)2

1( 1

0

for 0)Re( s

ii) Riemann’s duality equation can be proven by a self-reciprocal function argument (see [25]

E. C. Titchmarsh, 2.7), i.e.

0

)sin()(2

)( dyxyyfxf

which holds for

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6

2

1

1

1)(

2 xexf

x

.

For

0

sinh

sinh)( dt

tx

ex

tx

it holds

dtdyxyJeyt

dyxy

xydt

t

eydyxyyx ty

ty

0 0

2/1

sinh

0 0

sinh

0

)(sinh

1)sin(2

sinh)sin()()(

and therefore

dtxtt

xdyxyy

0

22

0)(sinh

1

sinh

12)sin()(

with dyexyJyxt

x ty sinh

2/1

0

2/1

22

2/1

)()(sinh

)2(

and

x

xxJ

sin2)(2/1

.

iii) for nx

ss enxJxh

1

1 )(:)( a Dirichlet type series can be defined in the form

(2.17) x

dxxhxss s

s )(2)()2

1(

0

for

1)Re( s

Proof of corollary 2.2 It holds

1

0

2/1

1

0

2/1

1)1(1

)2

1(:)(

tt

dt

t

te

x

dxxessW

s

t

t

sx

leads to

0

))(2

1()( nxnxg with

0

)1

(1

)2

1(

sin x

dxx

xg

xs

s

s

Examples 2.4

i)

n

s

ndxxxdxx

ssW

nss

1

1

)1()(

1:)(

1

0 0

1

0

11

1 , 0)Re( s ,

ii)

0

1

0

1

1

0

11

2 )(11sin

)1,(:)( dxxxx

dx

x

xxdx

x

x

sssBsW s

sss

ii)

1

0

1

1

0

1

3 )(1sin

coscot:)( dxxx

x

dx

x

xx

x

xxsW s

ss

for 1)Re(0 s

iii)

1

0

1

0

1

0

1

4 )(1

1

1

)1(

1

1

)(

)(:)( dxxx

n

s

ndx

x

x

s

ssW s

ns

, 0)Re( s ,

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7

1

0

1

)1(

log

)(

)(

sindxx

x

x

s

s

s

s

s

iv) ??)()(:)(

1

0

1

5 dxxxssW s

0

1

0

5 )()1

(1

?)(sin x

dxxxg

x

dxx

xg

xsW

s

ss

with

0 1

4 ))(1()1())(1(?)( nn xnxnWxg .

3. Bessel function theory

The Bessel functions (see [26] G.N. Watson 13-74) in the form

(3.1)

)

2()

2(2)(:)( 2

2

2

22

xY

xJxxNxN with

2

1:

can be used to define an appropriate new measure dxxNxdN )(:)( .

From (3.2) below it’s being deduced (see [26] G.N. Watson 13-74) that )(2

xN is an

increasing function when 1 , using the fact that t tanh is an increasing function of ,

when 0 and therefore the last term in (2.3) below is negative or positive according to

1 or 10 . The analysis below is applicable for 10 ; we restrict ourselves to

the critical value 2

1: .

)(2

xN has a representation in the form (see [26] G.N. Watson 6-22, 6-3, 7-31, 13-74, 13-

75)

(3.2) dttttttxKxN

tanhtanhcoshtanh)sinh(32

)(0

0

2

with

(3.3)

t

dt

t

eedtedt

t

xtdtexK

txxtixtx

21

22

1

1

)cos()( sinh

02

0

cosh

0

from which it’s being deduced (see [26] G.N. Watson 13-74) that )(2

xN is an increasing

function when 1 , using the fact that t tanh is an increasing function of , when

0 and therefore the last term in (2.3) below is negative or positive according to 1 or

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8

10 . The analysis below is applicable for 10 ; we restrict ourselves to the critical

value 2

1: .

Lemma 3.1 The function )(xN can be represented as infinite integral in the form

0

sinh

sinh)(

t

dte

xxN tx

Proof of lemma 3.1 We recall from [11] I.S. Gradshteyn, I.M. Ryzhik (6.518) the formula

(3.4)

0

2

222

)sinh2()()(cos

dttxKxYxJ

for

2

1)Re(

2

1 .

Putting 4

1: , using

2

1

4sin

4cos

and

x

exK

x

2

)(2/1

leads to

0

sinh

20 2

12sinh22

12)sinh(4

cos

2)( dttx

exdttxKxxN

tx

(3.5) i.e.

0

sinh

sinh

1)(

t

dtexxN tx

Corollary 3.1 The function

(3.6)

0

sinh2

4

14

12

4

14

1

sinh)

2()()

2()(2:)(

t

dtexYx

xJxx

tx

and its Fourier transform

can be represented as infinite integral

(3.7)

0

sinh

sinh)( dt

t

ex

tx

,

0

sinhsinh)( dtetx tx

(3.8)

0

sinh4

sinh

1

4

1)(ˆ

2

1dte

tx t

x

,

0

2

sinh4

sinh224

1)(ˆ

2

1

t

dtex t

x

.

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9

Proof of corollary 3.1: It holds

(3.9)

00

sinh2 ))(,(

sinh2

1)(

2

12

dttxfdtt

ex

tx

whereby 2)(

)(2

1:))(,( yte

ttyf

with tt sinh:)( and its Fourier transform

(3.10) )(4

2

4)(

1),(ˆ te

tf

.

It follows

(3.11)

0

sinh42

2

sinh

1

4

1)(ˆ

2

1dte

tx t

From [26] G.N. Watson 6-22, 13-72 and 13-75 we note

dttexK tix

2

cosh2

1)(

4cos sinh

2

resp.

dttexK tx

0

cosh

22

cosh)(

dttxKxK )cosh2(2:)(0

2

2

.

From [11] I.S. Gradshteyn, I.M. Ryzhik (6.518), (6.544) we note

0

2

2

2

2

2

)sinh2()()(

2cos

dttxKxYxJ

for 1)Re(1

0

sinh2

2

0

2

2

2

2

2 22

sinh

2

1)sinh()(

1)sinh2(

de

x

tdtK

xK

xtxK

tx

From [26] G.N. Watson 15-61 we note for 2

:

)()(4

)( 222

2

2 rYrJreK

i

.

From [26] G.N. Watson 7-15 we further note for 2

1:

mxm

mm

x

xY

xJ 2

222222

0

22

!

))12()...(3)(1()12...(*3*1

4)

2()

2(

.

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10

Remark 3.4 An alternative representation of the function )(xN (see [26] G.N. Watson 7-31,

15-5, 15-53) is given by

(3.12)

dx

dxYxJx

1)()(

2

22

resp. )(1

8

)(

8)2(

xxxN

whereby

)(

)(arctan:)(

xJ

xYx

with

0)()(

)/(222

xYxJ

x

dx

d

and

)(

)(arctan:)(

0

0

xP

xQx with

)()(

)/(222

0 0xQxP

x

dx

d

with .......16384

3417

512

33

8

1)(tan)(

53 xxxxx

and )(0 xP and )(0 xQ appropriate polynomials related to )(0 xJ , )(0 xY defined by

(3.13)

)()

4sin()()

4cos(

2)(0 xQxxPx

xxJ

)()

4cos()()

4sin(

2)(0 xQxxPx

xxY

It holds (see [26] G.N. Watson 15-52)

(3.14) )(42

)( xxx

and

0)(

)()(1

)(

)(2

22

0

0

0

0

0

xP

xQxP

xP

xQ

dx

d

with link to e.g. Euler’s investigations of the zeros of

(3.15)

1

00 )1()02()2(n n

xJxJ

and to e.g. the measure

(3.16) xdxQxPxd log)()(:)( 22 .

With reference to (1.31) and (2.2) above we mention (see [26] G.N. Watson 13-21)

(3.17)

xx

t

t

dttK

t

dte )(0 .

With reference to remark 1.1 we mention Hadamard’s formula ([8] H.M. Edwards 2.1)

(3.18)

)1()0()(s

s .

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11

We note that for

)(

)(arctan:)(

4/1

4/1

xJ

xYx it holds

(3.19) x

dx

x

dxN

)(

8

1

))(8

1(

x

dx

x

dxN

which leads with proposition 1.3 to the following formula

(3.20) )2

1()

2()

2

1()

1()(

20

1

sss

x

d

xNxNx s

()(

8:)(

xNdx

dxQ

!??!!!!).

Remark A

From [26] G.N. Watson 14-4, 14-42 we recall Hankel’s repeated integral and its inversion, i.e.

Let )(RF be an arbitrary function of the real variable R subject to the condition that

0

)( dRRRF exists and is absolutely convergent; and let the order of of the Bessel

functions be not less than 2/1 . Then

)0()0(2

1)()()()()()(

0 00 0

rFrFRdRuduurJuRJRFRdRurJuRJRFudu

provided that the positive number r lies inside an interval in which )(RF has limited

total fluctuation.

From [26] G.N. Watson 18-24 we recall the sum of the Fourier-Bessel expansion for a given

function, i.e.

Let )(tf be a function defined arbitrarily in the interval )1,0( ; and let

0

)( dtttf exists

and let it be absolutely convergent. Let

01

2)()(

)(

2dttjJttf

jJa m

m

m

where 02

1 . Let x be any interval point of an interval ),( ba such that 10 ba

and such that )(tf has limited total fluctuation in ),( ba . Then the series

1

)( xjJa mm

is convergent and its sum is given by

1

)0()0(2

1)( rfrfxjJa mm

.

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12

4. Zeta function theory

The Zeta function )(s can be defined in the critical stripe 1)Re(0 s as a complex-

valued transform of an integral operator with normal distribution measure, i.e. for

(4.1)

1

:)( nxexR

it holds (see [25] E.C. Titchmarsh, 2.11)

(4.2) x

dxdte

xxRxss ts

00

1)()()( for 1)Re(0 s .

Müntz’ formula (see [25] E.C. Titchmarsh, 2.11) gives the Zeta function )(s as Mellin

transform of an integral operator in a more general form, i.e. it holds

Lemma 4.1 (Müntz’ formula) For )(),( xx continuous and bounded in any finite interval

with )()( xox and )()( xox for x and 1, it holds

(4.3)

x

dxdtt

xnxx

x

dxxxs ss

0100

)(1

)()(

)(

for 1)Re(0 s .

Proof:

i) because )(x is continuous and bounded in any finite interval with )()( xox it holds

1 0

1 )(1

dxxxn

s

s exists for 1

i.e. the inversion leading to the left hand side of (4.3) is justified.

ii) )1())(()1()()()()(/1

/1

0001

OdtxtOxdtOxdttttxdtxtnxx

x

The first summand is justified, because )(x is continuous and bounded in any finite interval

the second summand is justified, because )()( xox , i.e. it holds

x

cOnx

)1()(1

with dttc

0

)( .

Hence

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13

1)()()(

111

1

010

s

c

x

dxnxx

x

dx

x

cnxx

x

dxnxx sss

for 0 except 1s . Also

11

2

s

cdxxc s

for 1

and therefore (4.3) for 1)Re(0 s

Remark 4.2

concerning an application of Polya’s criterion in combination with an application of Müntz

formula it holds from [19] G. Polya, p. 365:

Polya's criterion cannot be applied to Muentz's formula.

Polya's criterion is for an integral over a finite interval and to extend it to an infinite interval it

needs certain conditions, see the notes by R.P. Boas in the second volume of Polya's

collected works.

In order to apply Polya's criterion to Muentz's formula one needs to show that the function

xnxxG

1)(:)(

1

*

is positive and increasing for 0x . It does not suffice to show this only for 1x , because

)(* xG is not the same as )1

(*

xG . However, )(* xG cannot be positive and increasing in the

whole range for x, because otherwise its value at infinity would be positive and not 0, as is

the case. Muentz's formula requires )(x to vanish at infinity to order x with 1 , hence

the corresponding function

dttx

nx

01

)(1

)(

has the value 0 at infinity. Therefore, this expression cannot be both positive and increasing

near infinity and Polya's criterion never applies to a formula of Muentz's type.

Remark 4.3 The standard “measure” in current Zeta function theory is

(4.4)

x

t

t

dtexEix )(:)(

with

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14

(4.5) x

dxexd

x

)(

, xx

dxxd

log)(log

,

0

)()( xdxs s .

(3.5) plays a key role in the analysis of Euler, Gauss and Riemann, e.g. Gauss’ Li-function is

defined by

(4.6)

x

xtx

x

xOttddt

exEi

t

dtxLi

log 00

)ln

()(logt

)(loglog

:)(

,

1x .

Euler’s )log(logx divergence (see [8] H.M. Edwards 1.1) can be stated by

(4.7) x

e

x

e

x

tdtt

dt

u

dux

p)(log

log)log(log

1log

11

and Riemann’s estimate of )()( xRx (see remark 3.xx below) is given by

(4.8)

xt

tdxRx

1

)(log)()(

2

(

xt

tdxRx

1

)(log)()(

2

).

Remark 4.4

This remark is about putting the new measure with its underlying Hilbert space in a Hilbert

scale context with reference to Riemann’s duality equation:

Basically the isometric property )(ˆ)( xfxf of the Gauss-Weierstrass density function is

used to prove Riemann’s duality (see [8] H.M. Edwards)

(4.9) )1()2

(2

)1)((:)( 2/ sss

sss s ,

which can be written in the form

(4.10)

0

1

0

)()1()()1)(()( dxxfxssdxxfxsss ss

.

Jacobi’s relation (see also [8] H.M. Edwards 10.3)

(4.11) )1

(1

)(21:21)(ˆ:)( 2

1

222

xG

xxenxfexG xnxn

implies, that the invariant operator is formally self-adjoint (see also [12] H. Hamburger and

[9] D. Gaier for relations to conformal mappings and singular integral operators). But the

operator has no transform at all, because the integral

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15

(4.12)

00

1 )()(

nxdFxx

dxxGx ss

does not converge for any s. The integral would converge at if the constant term of (1.27)

above, which is basically )0(f , is absent. Roughly speaking the measure dxxf )( solves

the issue, but the prize to be paid is a scale of higher regularly, jeopardizing adequate self-

adjoint properties.

Riemann’s duality can be derived from the representation

0

2/

1

2/)1(2/2/)1(2/ )()1(

1)()

2

1()1()

2()(

x

dxxx

ssx

dxxxx

ss

ss sssss

with x

ex xn

2

1:)(

1

2

whereby

)1

(1

)(

4/1

4/1

xxxx

.

Remark 4.5

Referring to Tauberian Theorems the integrals

0

)(xdx s and

0

)(xdx s show the same

divergence behavior for 0s

as )1( , which can be seen from

(4.13)

)2

2/1()

2

)2/1(

2

11)(

)(

0

sssdx

x

xex

xs

We note the relations ([26] G.N. Watson 13.6)

i

i

s

xs

dsx

ss

s

idt

t

tJ

)2

1(

)2

1(

2

1)(0

and

2

1

)!

11(

!

)1(

t

)t(2:)(

kk

x

kdt

Jex

kk

x

o

t

with

.…0.57721566)1

log(log(log)1()0(

1

00

dtt

tdte x .

The Mellin transforms of )(0 xJ , )(0 xY , )(xKo are given in [26] G.N. Watson 13.21, 13-24,

13-3). We mention the formulas

2loglog)(0

0

tdttJ

,

0

2

2log dtt

ee tt

,

0)(0

0

dttY .

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16

Remark 4.6

We mention the following equivalent formulation for the Riemann conjecture (see [8]

Edwards, chapter 5)

(4.14) )()()ln()()( 2

1

xOxLixxOxLix

and Euler’s formula

(4.15) )(log!

)1()(

1

1

x

eOx

k

x

kt

dtex

xkk

x

t

resp. )ln

()(x

xOxLi ,

see [1] B. C. Berndt, Ramanujan’s corollary 2, chapter 4 . Riemann’s estimate is essentially

based on the analysis of the function:

0)Re(

0)Re(

.....

....

)(log

)(log

)1log(1

2

1)(

for

for

tdt

tdt

dsxs

siH

x

o

x

ia

ia

s

The new “measure” (x.y) motivates the alternative function

0)Re(

0)Re(

.....

....

)(log

)(log

:)(*

for

for

tdt

tdt

Hx

o

x

to be put into the context of Gauss’ Li-function (1.22) and Riemann’s formula (see [8] H.M.

Edwards 1.14)

(4.16) s

dsxs

idt

t

txLixLixLixJ s

ia

ian x

n

)(log2

1)0(log

log)()()()(

121

0)Im(

Analyzing analogue convergence behavior to

(4.17) )(11

0 0

log)1(1

xLidrr

edr

r

x xrr

(4.18)

0)Im(

1

0

log

)()(

xLixLidt

t

edr

r

xx tr

,

and to the density

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17

(4.19)

0

log

1drx

x

r .

(3.19) is roughly speaking the density of the primes. Note that due to Euler it holds

0

)(logt

dteex txt for 0)Re( x .

Riemann analyzed the expression

(4.20) dsxs

s

ds

d

xis

dsxs

ixJ

ia

ia

s

ia

ia

s

)(log

log

1

2

1)(log

2

1)(

for 1a

to prove the convergence estimate

(4.21)

x

n

xt

tdt

ttt

dtxRx

log

log

log)1()()(

1

2

2

applying the Fourier inverse technique (see [8] H.M. Edwards 1.14 ff.). He used the following

Lemma: For dsxs

sds

d

xiH

ia

ia

s

)1log(

1

log

1

2

1:)(

with C

it holds

0)Re(

0)Re(

.....

....

)(log

)(log

)1log(1

2

1)(

for

for

tdt

tdt

dsxs

siH

x

o

x

ia

ia

s

For )1,( it follows

(4.22) )1log(log)()(0)Im(

1

sxLixLi

(4.22) is only conditionally convergent, it must be summed in order of increasing )Im( .

(4.23) is the critical term concerning an appropriate convergence behavior like (x.y), due to

its oscillating behavior. Using the new measure with the alternative Li-function (x.y) the

(convergence) damping behavior of Bessel functions first and second kind to infinite and to

zero should provide significant contribution to overcome this issue.

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18

Remark 4.7

In [5] D. Bump et.al. it’s shown that the zeros of the transforms of the Hermite polynomials lie

all on the critical line. The Hermite polynomials are the orthogonal polynomial system related

to the normal distribution, building the eigenfunctions )(xn of the quantum harmonic

oscillator with its ground state )()( 210 xcfcx .

The relation of the Hermite polynomials to the density )(xdF in relation to the concept of

convolution operators is given in [6] D.A. Cardon.

Both analysis’ could be applied replacing )(xdF by )(xdN .

The Bessel function )(0 xK plays a key role in the analysis of the next section. The analysis

technique of [10] G. Gasper might be applicable using the Mellin transform of )(0 xK (see

[25] G. N. Watson 13-21), which is

(4.24)

)2

(4

1)2( 2

0

0

1 sdxxKx s

for )Re(0 s .

or the relation (2.2) ff. below.

Remark 4.8

A famous usage of Dirichlet’s series is in the context of Planck’s black-body radiation

function

(4.25)

1

/

5

1

/5

1 2

2 1

1),( Tnc

Tce

c

e

c

d

TdR

with 2

1 2 hcc and khcc /2 . The relation to the Zeta function

(4.26)

01

)()(x

dx

e

xss

x

s

is given by

(4.27)

0 1

4

0 1

44

)()()4()4(90 x

dxex

x

dxex x

n

nx

.

(4.42) describes the total radiation and its spectral density at the same time, i.e.

(4.28) dxx

gx

dx

e

x

x

dx

e

xdxxg

xx)

1(

11)(

4

/1

4

.

The new measure dxxN )( resp. the “measure” )(xd allows a modified definition of this

radiation function.

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19

Referring to the probability model of the location of an electron we recall Parseval’s equation

(see [8] Edwards 10.7), which G.H. Hardy used (see [8] H.M. Edwards 11.1), to prove that

there are infinitely many roots of 0)( on the line 2/1)Re( s . With lemma 1.2 and

lemma 2.6 it holds

dsss

ssi

dxxNx

i

i

2/1

2/1

2

0

2)

2

2/1()

2

)2/3()1()

2

1(

2

1)(2

(4.29)

dsss

sssi

dxxNx

i

i

s

2/1

2/1

223

0

2

)2

2/1()

2

)2/3()

2

1()

2

3)(

2

1(

2

2)(ˆ2

.

Remark 4.9

A modified norm to the standard inner product

0

2)()(),( dxxfxffff

can be defined in the form

(4.30) dxdtt

tt

td

edxxNxfft

x

0 0 0

sinh4

0

22

2tanh

2

1tanh

2coshtanh

16)()(:

22

where

02

tanh2

1tanh

tt .

The above might be seen as a step forwards “The Road to Reality”, as it’s about complex

number systems in combination with “real” duality (see [15] R. Penrose 34.8) in the context

of location and frequency probability.

The Helmholtz equation with space dimension n

is given by

inuui

0

2

where i represents the Dirac delta function at the source point i corresponding to the

fundamental solution. The domain can be unbounded or bounded with or without

boundary conditions; x denotes the n-dimensional coordinate variable and kk xxr :

The kernel wavelet basis functions are

)()2(4

:)( )2(

12/

2/12/1

kn

n

k

n

kn rHri

rh

, 2n

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20

where nh comply with the divergence (conservation) theorem

1)1(lim 1

k

n

n

n

kr

gSr

,

0kr

and nh satisfy the Sommerfeld radiation condition at infinity

0lim

n

k

n gir

gr , kr

The link to the density function (2.1) below is given by

)()()()()( 2

2

2

2

2

2

)2(

12/

)1(

12/

2)1(

12/ rYrJrrHrrHrHr nnnnn

With reference to fractional mathematics we note that 4

1: in (2.1) would correspond to a

fractional dimension of space of 5.2n .

Using the Hankel functions

)()(:)()1( xiYxJxH resp. )()(:)()2( xiYxJxH

and

2)1()2()1(222 )()()()()(:)( xHxHxHxYxJxR

it follows

iexRxH )()()1( resp.

iexRxH )()()2( .

Putting )(:)(4

1 xx ...... can be re-formulated to

x

dxdxR

)(

2

2

resp. x

dxdixKd

x

xN

2

4

1 )(2

8

)2(

With reference to (x.y) and remark x.y below we mention

)(22)1( )()()()()(ri

erYrJriYrJrH

resp. )(1

2

)(

2

4)2()(

)()()()1(

r

e

r

eerNrH

ririri

with 4

1:

which might motivate an alternative or additional “polar” coordinate transformation in the

context of Riemann manifolds.

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21

The simplest version of the harmonic oscillator is the Hamiltonian system with Hamiltonian

)(2

1),( 222 qpqpH

and pq , qp , qq 2

Identifying CR 2 by putting qipz a solution to 2

2

1),( zqpH

is given in the form

tiCetz )( .

Remark 4.10 (just to kick off a next level of brainstorming --> linkage hyperbolic functions

and strings)

With respect to Lemma 1.2 we mention the somehow “birthday” of the Superstring theory. In

1968 Gabriel Veneziano and Mahiko Suzuki came across using the Euler beta function to

describe interactions of elementary particles:

Consider an elastic scattering process with 2 incoming spinless particles of transverse

momenta 21, pp , outgoing particles of momenta 43 , pp . With a metric with signature

,...,,, the mass squared of a particle is 22 pm . The conventional Mandelstam

variables are defined as

2

21 )( pps , 2

32 )( ppt , 2

31 )( ppu .

which obey the one identity

imuts .

The largest )(sJ value at given s with 22 )2( pms the square of the energy in the center

of mass frame and the angular momentum prr

pJ 2

2 formed the so-called “leading

trajectory”. Experimentally, it was discovered that the leading trajectories were almost linear

in s.

In the field theory of the weak interactions the simplest model amplitude ),( tsA is constructed

as a sum of s-channel & t-channel input diagrams in the form

)(

1)())(),((

))()((

))(())((),(),(

0 sjj

jttsB

ts

tsstAtsA

j

,

that shows poles, where the resonance of the leading (Regge) trajectories )(s is necessarily

linear in s, i.e. )0()( xx with the “daughter trajectories” nss )0()( , (postulated

by Veneziano), to achieve, that the formula is physically acceptable. )0( depends on the

quantum numbers such as strangeness and baryon number, but appeared to be

universal, approximately, i.e.

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22

tconsGeV

tan1

1

2

Regge slope

)0()( xx linear Regge trajectory.

A resonance occurs at those s values where )(s is a nonnegative integer (mesons) or a

nonnegative integer plus ½ (baryons).

Ns )( mesons

Ns 2/1)( baryons

which gives some relation to our

0

* )(2)2

1(),1()( dxxxsssBs s .

Remark 4.11

A wavelet transform is similar as a Fourier transform, which delivers the frequency spectrum

of a timely signal f(t) without any loss of information, although the Fourier transform itself

gives the frequencies without any information about the points in time, when the frequencies

occur. The wavelet transform delivers this sort of information in a better distinguishing form:

one gets both the frequency analysis and the points in time, when those frequencies happen,

similar like the written notes, which results into the music of an orchestra, which are

described in form of a wavelet transform on a 2-dimensional paper ([23] M. du Sautoy: “the

primes have music in them”)

A wavelet is a function )()( 2 RLx with a Fourier transform which fulfills

dc

2)(ˆ

2:0 .

The wavelet transform of a function )()( 2 RLxf with the wavelet )()( 2 RLx is the function

dt

a

bt

atf

cdtttf

cbafW ab )(

1)(

1)()(

1:),( ,

, RbRa ,0

For a wavelet )()( 1 RLx its Fourier transform is continuous and fulfills

dt)(2

1)0(ˆ0

The wavelet transform to the wavelet )()( 2 RLx

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23

),()(:2

2

22a

dadbRLRLW ,

is isometric and for the adjoint operator

)(),(: 22

2

2

* RLa

dadbRLW

2

* ),()(1

)(1

:),(a

dadbbag

a

bt

atg

cbagW

it holds IdWW

* and

)(

*

Wrange

PWW .

The continuous wavelet transform is known in pure mathematics as Calderón’s reproducing

formula, i.e. for )()( 1

nRLx real and radial with vanishing mean, i.e.

1)(ˆ

0

2

daa

a

It holds for )(1

:)(a

x

ax

na Calderón’s formula, i.e.

a

daff aa

0

** .

Classical Hilbert spaces in complex analysis are examples of wavelets, like Hardy space of

2L functions on the unit circle with analytical continuation inside the unit disk.

We note that )( 2x has a similar structure than the Mexican hut, which is a continuous

wavelet function (see remark 1.16 below) )()1()( 2

2/22/2

22

RLexedx

dx xx

fulfilling

dc

2)(ˆ

2:0 .