Abc, high quality commas, and epimericity: Difference between revisions

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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2012-09-07 14:10:32 UTC</tt>.<br>
: This revision was by author [[User:guest|guest]] and made on <tt>2012-09-07 15:16:55 UTC</tt>.<br>
: The original revision id was <tt>362891216</tt>.<br>
: The original revision id was <tt>362907958</tt>.<br>
: The revision comment was: <tt></tt><br>
: The revision comment was: <tt></tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
<h4>Original Wikitext content:</h4>
<h4>Original Wikitext content:</h4>
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;white-space: pre-wrap ! important" class="old-revision-html">If n/d &gt; 1 is a rational number with positive integers n and d relatively prime, we may define the //epimericity// of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that [[http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem|Størmer's theorem]] generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than any constant c less than one. Hence "interesting" commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;white-space: pre-wrap ! important" class="old-revision-html">If n/d &gt; 1 is a rational number with positive integers n and d relatively prime, we may define the //epimericity// of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that [[http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem|Størmer's theorem]] generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than or equal to any constant c less than one. Hence "interesting" commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.


This conjecture is related to the [[http://en.wikipedia.org/wiki/Abc_conjecture|abc conjecture]], and a related claim is in fact precisely the abc conjecture, which defines what we may call a //high quality comma//. Define the //radical// rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the //quality// q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ &gt; 0 there are only finitely many commas such that q(n/d) &gt; 1+ϵ. Any comma with q(n/d) &gt; 1 we may call "high quality"; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... .
This conjecture is related to the [[http://en.wikipedia.org/wiki/Abc_conjecture|abc conjecture]], and a related claim is in fact precisely the abc conjecture, which defines what we may call a //high quality comma//. Define the //radical// rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the //quality// q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ &gt; 0 there are only finitely many commas such that q(n/d) &gt; 1+ϵ. Any comma with q(n/d) &gt; 1 we may call "high quality"; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... .


=Links=
=Links=  
[[http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&amp;l=1|Seven and eleven limit comma lists]]
[[http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&amp;l=1|Seven and eleven limit comma lists]]
[[http://tech.groups.yahoo.com/group/tuning-math/message/5556|An 11-limit linear temperament top 100 list]]
[[http://tech.groups.yahoo.com/group/tuning-math/message/5556|An 11-limit linear temperament top 100 list]]
</pre></div>
[[Superpartient|Degree of Epimericity]]</pre></div>
<h4>Original HTML content:</h4>
<h4>Original HTML content:</h4>
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;ABC, High Quality Commas, and Epimericity&lt;/title&gt;&lt;/head&gt;&lt;body&gt;If n/d &amp;gt; 1 is a rational number with positive integers n and d relatively prime, we may define the &lt;em&gt;epimericity&lt;/em&gt; of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem" rel="nofollow"&gt;Størmer's theorem&lt;/a&gt; generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than any constant c less than one. Hence &amp;quot;interesting&amp;quot; commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.&lt;br /&gt;
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;ABC, High Quality Commas, and Epimericity&lt;/title&gt;&lt;/head&gt;&lt;body&gt;If n/d &amp;gt; 1 is a rational number with positive integers n and d relatively prime, we may define the &lt;em&gt;epimericity&lt;/em&gt; of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem" rel="nofollow"&gt;Størmer's theorem&lt;/a&gt; generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than or equal to any constant c less than one. Hence &amp;quot;interesting&amp;quot; commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
This conjecture is related to the &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Abc_conjecture" rel="nofollow"&gt;abc conjecture&lt;/a&gt;, and a related claim is in fact precisely the abc conjecture, which defines what we may call a &lt;em&gt;high quality comma&lt;/em&gt;. Define the &lt;em&gt;radical&lt;/em&gt; rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the &lt;em&gt;quality&lt;/em&gt; q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ &amp;gt; 0 there are only finitely many commas such that q(n/d) &amp;gt; 1+ϵ. Any comma with q(n/d) &amp;gt; 1 we may call &amp;quot;high quality&amp;quot;; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... . &lt;br /&gt;
This conjecture is related to the &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Abc_conjecture" rel="nofollow"&gt;abc conjecture&lt;/a&gt;, and a related claim is in fact precisely the abc conjecture, which defines what we may call a &lt;em&gt;high quality comma&lt;/em&gt;. Define the &lt;em&gt;radical&lt;/em&gt; rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the &lt;em&gt;quality&lt;/em&gt; q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ &amp;gt; 0 there are only finitely many commas such that q(n/d) &amp;gt; 1+ϵ. Any comma with q(n/d) &amp;gt; 1 we may call &amp;quot;high quality&amp;quot;; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... .&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="Links"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Links&lt;/h1&gt;
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h1&amp;gt; --&gt;&lt;h1 id="toc0"&gt;&lt;a name="Links"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt;Links&lt;/h1&gt;
&lt;a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&amp;amp;l=1" rel="nofollow"&gt;Seven and eleven limit comma lists&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&amp;amp;l=1" rel="nofollow"&gt;Seven and eleven limit comma lists&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/5556" rel="nofollow"&gt;An 11-limit linear temperament top 100 list&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
&lt;a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/5556" rel="nofollow"&gt;An 11-limit linear temperament top 100 list&lt;/a&gt;&lt;br /&gt;
&lt;a class="wiki_link" href="/Superpartient"&gt;Degree of Epimericity&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>

Revision as of 15:16, 7 September 2012

IMPORTED REVISION FROM WIKISPACES

This is an imported revision from Wikispaces. The revision metadata is included below for reference:

This revision was by author guest and made on 2012-09-07 15:16:55 UTC.
The original revision id was 362907958.
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:

If n/d > 1 is a rational number with positive integers n and d relatively prime, we may define the //epimericity// of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that [[http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem|Størmer's theorem]] generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than or equal to any constant c less than one. Hence "interesting" commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.

This conjecture is related to the [[http://en.wikipedia.org/wiki/Abc_conjecture|abc conjecture]], and a related claim is in fact precisely the abc conjecture, which defines what we may call a //high quality comma//. Define the //radical// rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the //quality// q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ > 0 there are only finitely many commas such that q(n/d) > 1+ϵ. Any comma with q(n/d) > 1 we may call "high quality"; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... .

=Links= 
[[http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&l=1|Seven and eleven limit comma lists]]
[[http://tech.groups.yahoo.com/group/tuning-math/message/5556|An 11-limit linear temperament top 100 list]]
[[Superpartient|Degree of Epimericity]]

Original HTML content:

<html><head><title>ABC, High Quality Commas, and Epimericity</title></head><body>If n/d &gt; 1 is a rational number with positive integers n and d relatively prime, we may define the <em>epimericity</em> of n/d as log(n-d)/log(d). Which logarithm we use is irrelevant; we can if we like use cents and so the epimericity is also cents(n-d)/cents(d). Then it appears to be true that <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/St%C3%B8rmer's_theorem" rel="nofollow">Størmer's theorem</a> generalizes to a claim that for any prime p, only finitely many rational numbers in the p-limit exist with epimericity less than or equal to any constant c less than one. Hence &quot;interesting&quot; commas in any p-limit can be defined as those below a given epimericity, such as the 7-limit commas under 0.5 in epimericity, or the 11-limit commas under 0.3.<br />
<br />
This conjecture is related to the <a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Abc_conjecture" rel="nofollow">abc conjecture</a>, and a related claim is in fact precisely the abc conjecture, which defines what we may call a <em>high quality comma</em>. Define the <em>radical</em> rad(n/d) of n/d as the product of all the primes dividing n, d, and n-d; so that rad(128/125) = 2*3*5 = 30. Then define the <em>quality</em> q(n/d) of n/d as log(n)/log(rad(n/d)). Then the abc conjecture, a very powerful conjecture, says that for any ϵ &gt; 0 there are only finitely many commas such that q(n/d) &gt; 1+ϵ. Any comma with q(n/d) &gt; 1 we may call &quot;high quality&quot;; there are an infinite number of these, but the conjecture is that there are only finitely many above any value greater than 1. High quality commas in the 5-limit include 250/243, 128/125, 3125/3072, 81/80 and 2048/2025. It should be noted that while every superparticular ratio has an epimericity of 0, merely being superparticular is by no means enough to make a comma high quality; the list of high-quality superparticulars starts 9/8, 49/48, 64/63, 81/80, 225/224, 243/242 ... .<br />
<br />
<!-- ws:start:WikiTextHeadingRule:0:&lt;h1&gt; --><h1 id="toc0"><a name="Links"></a><!-- ws:end:WikiTextHeadingRule:0 -->Links</h1>
 <a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/4458?threaded=1&amp;l=1" rel="nofollow">Seven and eleven limit comma lists</a><br />
<a class="wiki_link_ext" href="http://tech.groups.yahoo.com/group/tuning-math/message/5556" rel="nofollow">An 11-limit linear temperament top 100 list</a><br />
<a class="wiki_link" href="/Superpartient">Degree of Epimericity</a></body></html>