Ryan's Working Page

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This revision was by author Sarzadoce and made on 2015-08-21 20:21:08 UTC.
The original revision id was 557147201.
The revision comment was:

The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.

Original Wikitext content:

=Attempt to backwards-engineer a Weil-weighted analog for "Zeta"= 

In Mike's Zeta Function Working Page, we see that zeta can be thought of as a superposition of weighted "cosine accuracy" functions for every unreduced rational:

[[math]]
\displaystyle
\left| \zeta(s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{(nd)^{a}}\right]
[[math]]

The cosines are weighted by 1/(nd)<span style="font-size: 11.6999998092651px; vertical-align: super;">a</span>. However, it is of interest to replace n*d with max(n,d)^2 to see if we can derive a Weil-weighted analog of the Zeta function. I will denote this function by f(s).

[[math]]
\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{\text{max}(n,d)^{2a}}\right]
[[math]]

Let's do a few manipulations, to try to work our way backwards to f(s):

[[math]]
\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{n^{2a}}\right]
[[math]]

[[math]]
\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n > d} \left[\frac{\left({\tfrac{n}{d}}\right)^{-bi} + \left({\tfrac{d}{n}}\right)^{-bi}}{n^{2a}}\right]
[[math]]

[[math]]
\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \text{Re} \left( \sum_{n > d} n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } \right)
[[math]]

[[math]]
\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n > d} \left[ n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } + n^{ - \left(2a-bi \right) } d^{ - \left( bi \right) } \right]
[[math]]

Note that the RHS of this equation can be broken up into a sum of conjugates. However, we ideally want to break it up into a //product// of conjugates, in order to solve for f(s). This is where I get stuck.

Original HTML content:

<html><head><title>Ryan's Working Page</title></head><body><!-- ws:start:WikiTextHeadingRule:6:&lt;h1&gt; --><h1 id="toc0"><a name="Attempt to backwards-engineer a Weil-weighted analog for &quot;Zeta&quot;"></a><!-- ws:end:WikiTextHeadingRule:6 -->Attempt to backwards-engineer a Weil-weighted analog for &quot;Zeta&quot;</h1>
 <br />
In Mike's Zeta Function Working Page, we see that zeta can be thought of as a superposition of weighted &quot;cosine accuracy&quot; functions for every unreduced rational:<br />
<br />
<!-- ws:start:WikiTextMathRule:0:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \zeta(s) \right|^2 = \zeta(2a) + 2 \sum_{n &gt; d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{(nd)^{a}}\right]&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \zeta(s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{(nd)^{a}}\right]</script><!-- ws:end:WikiTextMathRule:0 --><br />
<br />
The cosines are weighted by 1/(nd)<span style="font-size: 11.6999998092651px; vertical-align: super;">a</span>. However, it is of interest to replace n*d with max(n,d)^2 to see if we can derive a Weil-weighted analog of the Zeta function. I will denote this function by f(s).<br />
<br />
<!-- ws:start:WikiTextMathRule:1:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n &gt; d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{\text{max}(n,d)^{2a}}\right]&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{\text{max}(n,d)^{2a}}\right]</script><!-- ws:end:WikiTextMathRule:1 --><br />
<br />
Let's do a few manipulations, to try to work our way backwards to f(s):<br />
<br />
<!-- ws:start:WikiTextMathRule:2:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n &gt; d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{n^{2a}}\right]&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \sum_{n > d} \left[\frac{\cos\left(b\ln\left(\tfrac{n}{d}\right)\right)}{n^{2a}}\right]</script><!-- ws:end:WikiTextMathRule:2 --><br />
<br />
<!-- ws:start:WikiTextMathRule:3:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n &gt; d} \left[\frac{\left({\tfrac{n}{d}}\right)^{-bi} + \left({\tfrac{d}{n}}\right)^{-bi}}{n^{2a}}\right]&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n > d} \left[\frac{\left({\tfrac{n}{d}}\right)^{-bi} + \left({\tfrac{d}{n}}\right)^{-bi}}{n^{2a}}\right]</script><!-- ws:end:WikiTextMathRule:3 --><br />
<br />
<!-- ws:start:WikiTextMathRule:4:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \text{Re} \left( \sum_{n &gt; d} n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } \right)&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + 2 \text{Re} \left( \sum_{n > d} n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } \right)</script><!-- ws:end:WikiTextMathRule:4 --><br />
<br />
<!-- ws:start:WikiTextMathRule:5:
[[math]]&lt;br/&gt;
\displaystyle&lt;br /&gt;
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n &gt; d} \left[ n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } + n^{ - \left(2a-bi \right) } d^{ - \left( bi \right) } \right]&lt;br/&gt;[[math]]
 --><script type="math/tex">\displaystyle
\left| \text{f} (s) \right|^2 = \zeta(2a) + \sum_{n > d} \left[ n^{ - \left(2a+bi \right) } d^{ - \left( -bi \right) } + n^{ - \left(2a-bi \right) } d^{ - \left( bi \right) } \right]</script><!-- ws:end:WikiTextMathRule:5 --><br />
<br />
Note that the RHS of this equation can be broken up into a sum of conjugates. However, we ideally want to break it up into a <em>product</em> of conjugates, in order to solve for f(s). This is where I get stuck.</body></html>