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My memory is that the idea is related to the smoothness of the metric/gauge terms: these should be C^2, so are sufficiently differentiable to be "best" approximated (at the second order that Whisky/GRHydro worked to) by the midpoint rule. However, if included
within the fluxes then they would implicitly go through the reconstruction/Riemann solve stage, so would - in places - be limited to lower accuracy.</div>
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I would not do this now - keeping the fully densitized terms together is cleaner and a better way to extend to high order.</div>
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Ian</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Roland Haas <rhaas@illinois.edu><br>
<b>Sent:</b> 31 October 2021 20:28<br>
<b>To:</b> Ian Hawke <I.Hawke@soton.ac.uk><br>
<b>Cc:</b> carpetx-developers@einsteintoolkit.org <carpetx-developers@einsteintoolkit.org><br>
<b>Subject:</b> Re: lapse terms in Whisky's fluxes</font>
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<div class="PlainText">CAUTION: This e-mail originated outside the University of Southampton.<br>
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