<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Yes; the "difference" is that the "num_flux" in the two cases are different (one will contain the lapse, the other not, as undensitized) [I think]. So the implemented case with the explicit averaged lapse at each interface should directly approximate the standard
form, but effectively uses a different reconstruction approach for gauge vs the rest of the flux.</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
I have memories of trying both approaches when playing with WENO reconstruction early on, and it making little difference. There should be no problem with scaling by any term that does not explicitly depend on terms within the hydro state vector.</div>
<div id="appendonsend"></div>
<hr style="display:inline-block;width:98%" tabindex="-1">
<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> 03 November 2021 15:31<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>
<div> </div>
</div>
<div class="BodyFragment"><font size="2"><span style="font-size:11pt;">
<div class="PlainText">CAUTION: This e-mail originated outside the University of Southampton.<br>
</div>
</span></font></div>
</body>
</html>