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<div class="moz-text-html" lang="x-unicode"> Theory Center Seminar <br>
Monday, February 5, 2018<br>
1:00 p.m. (coffee at 12:45 p.m.)<br>
CEBAF Center, Room L102 <br>
<br>
Mithat Unsal <br>
North Carolina State University<br>
<br>
<b>Aspects of Resurgence and Picard-Lefchetz Theory in QFT <br>
<br>
</b> Recent works show that there may indeed exist a
non-perturbative continuum definition of quantum field theory
(QFT), <br>
at least in some interesting regimes. I will describe some new
ideas from mathematics and physics, in particular, the <br>
resurgence theory, the trans-series framework from mathematics and
the idea of adiabatic continuity from physics to <br>
provide new insights into the structure of general QFTs. The new
techniques allow us to determine new saddle points <br>
which play important dynamical roles, e.g. in confinement,
theta-dependence in semi-classically calculable domains. <br>
It also provides new insights into the nature of IR-renormalon
problem. In a wide class of quantum mechanical systems, <br>
these techniques show that all non-perturbative data is secretly
encoded in perturbation theory. <br>
<br>
<br>
The link to remotely connect via bluejeans is available at <a
class="moz-txt-link-freetext"
href="https://www.jlab.org/div_dept/theory/seminars/2018-spring-theory-seminar.html">https://www.jlab.org/div_dept/theory/seminars/2018-spring-theory-seminar.html</a>
<br>
The (partial) schedule for the next seminars is available at the
same page. </div>
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