<html>#963: Improve McLachlan accuracy
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<tr><td style='text-align:right'> Reporter:</td><td>Erik Schnetter</td></tr>
<tr><td style='text-align:right'> Status:</td><td>open</td></tr>
<tr><td style='text-align:right'>Milestone:</td><td></td></tr>
<tr><td style='text-align:right'> Version:</td><td></td></tr>
<tr><td style='text-align:right'> Type:</td><td>enhancement</td></tr>
<tr><td style='text-align:right'> Priority:</td><td>minor</td></tr>
<tr><td style='text-align:right'>Component:</td><td>EinsteinToolkit thorn</td></tr>
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<p>Comment (by Zach Etienne):</p>
<p>The “Duez et al” trick is quite powerful – I implemented this trick in Baikal a few months ago and found H constraint violations drop by about an order of magnitude compared to when it’s not enabled, for binary black hole simulations (e.g., a ET BBH gallery example - like simulation).</p>
<p>The trick dates back to Yoneda & Shinkai <a data-is-external-link="true" href="https://arxiv.org/abs/gr-qc/0204002" rel="nofollow">https://arxiv.org/abs/gr-qc/0204002</a> , who did an analytical (non-numerical) investigation</p>
<p>… and Duez et al I think were the first to report its use in NR simulations: <a data-is-external-link="true" href="https://arxiv.org/abs/gr-qc/0209102" rel="nofollow">https://arxiv.org/abs/gr-qc/0209102</a></p>
<p>In addition Raithel & Paschalidis recently found that this trick improves H constraint convergence behavior in the context of binary neutron star simulations: <a data-is-external-link="true" href="https://arxiv.org/abs/2204.00698" rel="nofollow">https://arxiv.org/abs/2204.00698</a></p>
<p>Future versions of Baikal/BaikalVacuum will have this trick enabled by default – I’m now calibrating the magnitude and scaling of the coefficient.</p>
<p>--<br/>
Ticket URL: <a href='https://bitbucket.org/einsteintoolkit/tickets/issues/963/improve-mclachlan-accuracy'>https://bitbucket.org/einsteintoolkit/tickets/issues/963/improve-mclachlan-accuracy</a></p>
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