<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
Dear All,</div>
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
Here are the details of the seminar this week -</div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
<b><br>
</b></div>
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
<b>Speaker: Bruno Alexandre </b>(Imperial College London)</div>
<div style="margin: 0px; max-width: 100%; min-height: 1px;"></div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
<br>
</div>
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif;">
<span style="font-size: 12pt; color: black;"><b><i>Seminar Date: 10th December</i>, Tuesday
</b></span><span style="font-size: 14pt; color: rgb(59, 32, 77);"><b>1.00 pm</b></span></div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
</div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
<b><i>Venue: Seminar</i></b> Room <b><u>A 113 </u>(Cripps North Building)</b></div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
</div>
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; background-color: white; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt;">
<span style="color: rgb(59, 32, 77);"> <b>Title: </b></span><span style="color: black;"><b><i> Higgs Mechanism for the Ashtekar Self-Dual Connection</i></b></span></div>
<div class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; background-color: white; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 15px; color: black;">
<b><br>
</b></div>
<div style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; background-color: white; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 15px; color: rgb(59, 32, 77);">
<b>A</b><span style="background-color: white;"><b><i>bstract:</i></b></span></div>
<p class="elementToProof" style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; background-color: rgb(255, 255, 255); margin: 0px;">
<span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;">We introduce the Higgs mechanism for the self-dual spin connection (also known as the Ashtekar connection), using the Plebanski formulation of gravity. We develop our formalism within
the framework of the chiral action and derive the equations of motion of the theory. One particular test</span></p>
<p style="text-align: left; text-indent: 0px; background-color: rgb(255, 255, 255); margin: 0px;">
<span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;">model is explored: since anisotropy is an intrinsic property of the theory, a modified version of the spatially flat Bianchi I model with two different scale factors is considered.
We apply our formalism and derive the Friedmann equations which regulate the scale factors and the Higgs field. We also</span></p>
<p style="text-align: left; text-indent: 0px; background-color: rgb(255, 255, 255); margin: 0px;">
<span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;">present a Proca-like term for the connection, which when reduced to minisuperspace with a positive Λ yields a De Sitter universe with an effective cosmological constant that depends
on the mass of</span></p>
<p class="elementToProof" style="text-align: left; text-indent: 0px; background-color: rgb(255, 255, 255); margin: 0px;">
<span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;">the gauge fields. We finally investigate the effect of these mass terms on gravitational waves and find that the wave equation remains unchanged relatively to GR; however the Weyl
tensor is scaled by a constant which depends on the mass of the connection components.</span></p>
<div style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; background-color: white; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 15px; color: black;">
<br>
</div>
<div style="direction: ltr; text-align: left; text-indent: 0px; line-height: 1.284; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
<br>
</div>
<div style="direction: ltr; text-align: left; text-indent: 0px; margin: 0px; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: black;">
Link to join: <a href="https://teams.microsoft.com/l/meetup-join/19%3ameeting_OGM3OTk5NzQtZWEwZS00ZmUyLTk3MGUtZjFhY2M5OTU2MjI1%40thread.v2/0?context=%7b%22Tid%22%3a%2267bda7ee-fd80-41ef-ac91-358418290a1e%22%2c%22Oid%22%3a%22f3250584-4b5f-48fa-a897-08e77f2246b7%22%7d" target="_blank" id="OWAf973cb03-40ab-06f4-6162-906b0e6558dc" class="OWAAutoLink" title="https://teams.microsoft.com/l/meetup-join/19%3ameeting_OGM3OTk5NzQtZWEwZS00ZmUyLTk3MGUtZjFhY2M5OTU2MjI1%40thread.v2/0?context=%7b%22Tid%22%3a%2267bda7ee-fd80-41ef-ac91-358418290a1e%22%2c%22Oid%22%3a%22f3250584-4b5f-48fa-a897-08e77f2246b7%22%7d" rel="noopener noreferrer" data-linkindex="0" data-auth="NotApplicable" data-ogsc="" style="margin: 0px;">
https://teams.microsoft.com/l/meetup-join/19%3ameeting_OGM3OTk5NzQtZWEwZS00ZmUyLTk3MGUtZjFhY2M5OTU2MjI1%40thread.v2/0?context=%7b%22Tid%22%3a%2267bda7ee-fd80-41ef-ac91-358418290a1e%22%2c%22Oid%22%3a%22f3250584-4b5f-48fa-a897-08e77f2246b7%22%7d</a></div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
With Regards,</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
-Swagat</div>
<p class="elementToProof" style="text-align: left; text-indent: 0px; margin: 0px;">
<span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;"><br>
</span></p>
<p style="text-align: left; text-indent: 0px; margin: 0px;"><span style="font-family: Aptos, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> </span></p>
<p style="text-align: left; text-indent: 0px; margin: 0px;"><span style="font-family: Aptos, sans-serif; font-size: 12pt; color: black;"><br>
</span></p>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div id="Signature" class="elementToProof" style="color: inherit;">
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(68, 68, 68); line-height: normal;"><b>Swagat Saurav Mishra</b></span><span style="font-size: 10pt; line-height: normal;">,</span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">Postdoctoral Research Associate</span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;"></span><span style="font-size: 11pt; color: rgb(32, 18, 77); line-height: normal;"><br>
</span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">Particle Cosmology Group, </span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">Centre for Astronomy and Particle Theory,</span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">University of Nottingham, Nottingham NG7 2RD, UK.</span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(0, 0, 0); line-height: normal;">Website</span><span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">:
</span><span style="font-size: 10pt; color: rgb(17, 85, 204); line-height: normal;"><a href="https://swagatam18.wordpress.com/" target="_blank" id="OWAf2822e4f-9f51-c30e-4806-51c2ff8c89b5" class="OWAAutoLink" style="color: rgb(17, 85, 204); margin-top: 0px; margin-bottom: 0px;">https://swagatam18.wordpress.com/</a></span><span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;"> </span></p>
<p style="text-align: left; line-height: normal; margin: 0px; font-family: "Helvetica Neue"; color: rgb(34, 34, 34);">
<span style="font-size: 10pt; color: rgb(0, 0, 0); line-height: normal;">Research Link</span><span style="font-size: 10pt; color: rgb(32, 18, 77); line-height: normal;">:</span><span style="font-size: 10pt; color: rgb(17, 85, 204); line-height: normal;"><a href="https://inspirehep.net/authors/1517353" target="_blank" id="OWAc91ab7e2-3c22-c8fd-f343-a0b38a28d7bc" class="OWAAutoLink" style="color: rgb(17, 85, 204); margin-top: 0px; margin-bottom: 0px;">https://inspirehep.net/authors/1517353</a></span></p>
<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><br>
</span></div>
</body>
</html>