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                  <div><b><font face="Times New Roman, Times, serif">High
                        Energy Theory Seminar -- Monday, May 17, 2021</font></b><font face="Times New Roman, Times, serif"><br>
                      <br>
                      "Superstring Amplitudes in Genus 0 and Double
                      Copy"<br>
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                      Location: via ZOOM -- Time: 2:30 PM<br>
                      <br>
                      Francis Brown, Oxford University<br>
                      <br>
                      <b><font color="#0000ff">To connect to the HET
                          Seminar via Zoom, please click the following
                          link:<br>
                          <br>
                        </font></b><font color="#0000ff"><font color="#000000"><a href="https://theias.zoom.us/j/83432499354?pwd=TkhMZWFJK2E1UzRyeUppU01pZVQwUT09" rel="nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer" target="_blank">https://theias.zoom.us/j/83432499354?pwd=TkhMZWFJK2E1UzRyeUppU01pZVQwUT09</a><br>
                          <br>
                          Abstract: This is joint work with ClĂ©ment
                          Dupont. Motivated by double-copy&nbsp;
                          (Kawai-Lewellen-Tye) formulae relating open
                          and closed superstring amplitudes at
                          tree-level, I will explain a general
                          double-copy formula for period integrals on
                          algebraic varieties and its relation to
                          single-valued functions. As an application, we
                          deduce a conjecture of Stieberger which states
                          that the passage from open to closed
                          amplitudes in string perturbation theory at
                          genus zero is given by the so-called
                          single-valued map. </font></font><b><font color="#0000ff"><br>
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                    <pre class="moz-signature">---------
Lisa Fleischer
School of Natural Sciences
Institute for Advanced Study
1 Einstein Drive
Princeton, NJ 08540
<a href="mailto:lisa@ias.edu" rel="nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer" target="_blank">lisa@ias.edu</a></pre>
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