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<div style=""><font style=""><font style="font-size: 12pt;"><font style=""><span style="color: rgb(255, 0, 0); font-size: 18pt;" data-mce-style="color: #ff0000; font-size: 18pt;"><strong><font face="Times New Roman, Times, serif">THIS SEMINAR HAS BEEN CANCELLED AND WILL BE RESCHEDULED</font></strong></span><u style=""><br><br></u></font></font> </font>
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</u><font face="Times New Roman, Times, serif"><b>Monday</b></font></font><font face="Times New Roman, Times, serif"><b style="color:rgb( 0 , 0 , 0 );font-size:12pt">,
March 27, 2023 - IAS High Energy Theory
Seminar </b><b style="color:rgb( 0 , 0 , 0 );font-size:12pt"><font color="#0563c1"><u><br>
</u></font></b><br>
"The Cosmic Neutrino Background (CνB): Its
Distribution on the Surface of the Earth and its
Manipulation by Laboratory-Scale Diffraction
Gratings"<br>
<br>
<span style="font-size:12pt"> Location:
Bloomberg Lecture Hall (IAS) & Zoom</span><br>
<br>
<span style="font-size:12pt"> Zoom Link: <a href="https://theias.zoom.us/j/84116605050?pwd=VHV6VkRUM3hkM2dFSlo2QWJiUWtPdz09" rel="nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer nofollow noopener noreferrer" target="_blank">https://theias.zoom.us/j/84116605050?pwd=VHV6VkRUM3hkM2dFSlo2QWJiUWtPdz09</a></span><br>
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<span style="font-size:12pt"> Time: 2:30 PM</span><br>
<span style="font-size:12pt"> </span><br>
<span style="font-size:12pt"> Speaker: </span></font></font><font face="Times New Roman, Times, serif" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif;">Savas
Dimopoulos, SITP, Stanford University<br>
<br>
<span style="color:rgb( 0 , 0 , 0 );font-size:12pt"></span><b>Abstract: </b>The
CνB is a cosmological relic analogous to the CMB,
and contains information about the universe before
it was one-second-old. Reflection of relic
neutrinos from the surface of the Earth creates a
significant local neutrino-antineutrino asymmetry
in a shell seven meters thick around the Earth's
surface. This asymmetry far exceeds the expected
primordial lepton asymmetry. The resulting
gradient of the net neutrino density evades the
forty-year-old “no-go” theorem on the vanishing
of O(G_Fermi) neutrino forces on matter.<br>
<br>
These forces can be further enhanced by using
1-100 meter structures with shape reminiscent of a
sea-urchin: they consist of rods of width w and
length L>>w periodically arranged on the
surface of the sphere of radius R~L. Such a
structure functions as a diffraction grating for
relic neutrinos and the induced
neutrino-antineutrino asymmetry at its center may
point to a new class of experiments to detect the
CνB in a laboratory setting. At the same time,
such structures can be used to similarly
manipulate dark matter. <br>
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<pre class="moz-signature" style="color: rgb(0, 0, 0); font-family: arial, helvetica, sans-serif; font-size: 12pt;"><font face="Times New Roman, Times, serif">---------------------
Lisa Fleischer
Academic Assistant
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 nofollow noopener noreferrer" target="_blank">lisa@ias.edu</a></font></pre>
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