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<p class="MsoNormal">I think there is a quote from Heinlein along the lines of “Never worry about theory as long as the machinery does what it's supposed to do.” When do we have to worry about first principles?<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Friam <friam-bounces@redfish.com> on behalf of Frank Wimberly <wimberly3@gmail.com><br>
<b>Reply-To: </b>The Friday Morning Applied Complexity Coffee Group <friam@redfish.com><br>
<b>Date: </b>Wednesday, May 13, 2020 at 8:31 PM<br>
<b>To: </b>The Friday Morning Applied Complexity Coffee Group <friam@redfish.com><br>
<b>Subject: </b>Re: [FRIAM] PSC Tornado Visualization (2008) [720p] - YouTube<o:p></o:p></span></p>
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<p class="MsoNormal">The fluid dynamics model used for that visualization is based on first principles. Many years ago Nick was trying to figure out how tornadoes develop. I told him I thought this was pretty well understood and I asked Droegemeier for a
paper. He sent one which I forwarded to Nick. It was full of advanced math. <o:p>
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<p class="MsoNormal">Frank<o:p></o:p></p>
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<p class="MsoNormal">---<br>
Frank C. Wimberly<br>
140 Calle Ojo Feliz, <br>
Santa Fe, NM 87505<br>
<br>
505 670-9918<br>
Santa Fe, NM<o:p></o:p></p>
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<p class="MsoNormal">On Wed, May 13, 2020, 9:23 PM Marcus Daniels <<a href="mailto:marcus@snoutfarm.com">marcus@snoutfarm.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Nick writes:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">“The result looks so much like iconic tornado vids that we wannabee tornado chasers idolize that one suspects that the video was back constructed from that film, rather than developing
organically from the physics.”<o:p></o:p></p>
<p>Suppose the equations were extracted, or the behavior re-generated, from a deep neural net (or whatever automated machine learning thing), but nonetheless were predictive of other tornados. One might reasonably ask, “Who cares?”<o:p></o:p></p>
<p>Marcus<o:p></o:p></p>
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