# Coming Events

## Seminar

Date/Time:
Monday, December 23, 2019 - 11:00
Venue:
SMS Seminar Hall
Speaker:
Dr Arpita Patra
Affiliation:
Department of Computer Science & Automation, Indian Institute of Science Bangalore, Bengaluru 560012, India
Title:
Secure Multi-party Computation over the Internet

Abstract: Secure Multi-party Computation (MPC), the standard-bearer and holy-grail problem in Cryptography, permits a collection of data-owners to compute a collaborative result, without any of them gaining any knowledge about the data provided by the other, except what is derivable from the final result of the computation. The first half of the talk will discuss garbled circuits and Yao's two-party computation. in the second half, if time permits, then I will discuss one of our recent works on MPC with small population and honest majority that builds on garbled circuits.-----Brief Bio: Dr Arpita Patra is an Assistant Professor at Indian Institute of Science. Her area of interest is Cryptography, focusing on theoretical and practical aspects of secure multiparty computation protocols. She received her PhD from Indian Institute of Technology (IIT), Madras and held post-doctoral positions at University of Bristol, UK, ETH Zurich, Switzerland and Aarhus University, Denmark. Her research has been recognized with an NASI Young Scientist Platinum Jubilee Award, a SERB Women Excellence award, an INAE Young Engineer award and associateships with various scientific bodies such as Indian Academy of Sciences (IAS), National Academy of Engineering (INAE ), The World Academy of Sciences (TWAS). She is a council member of Indian Association for Research in Computing Science (IARCS) since December 2017.

## Seminar

Date/Time:
Monday, December 23, 2019 - 14:30 to 15:30
Venue:
Mathematics Seminar Room
Speaker:
Amit Kumar
Affiliation:
NISER
Title:
Partial isometries in absolute matrix order unit spaces

In this talk, we shall introduce the notions of absolutely matrix ordered spaces and absolute matrix order unit spaces in the context of matrix ordered spaces. We shall prove that a unital, bijective $\ast$-linear map between absolute matrix order unit spaces is a complete isometry if, and only if, it is a completely absolute value preserving. From here, we deduce that on (unital) C$^*$-algebras such maps are precisely C$^*$-algebra isomorphisms. We shall extend the notion of orthogonality to the general elements of an absolute matrix order unit space and relate it to the orthogonality among positive elements. We shall introduce the notion of a partial isometry in an absolute matrix order unit space to describe the comparison of order projections. We shall also discuss direct limit of absolute matrix order unit spaces to show the existence of Grothendieck group" through order projections and prove that Grothendieck group" is a functor from category of absolute matrix order unit spaces with morphisms as unital completely absolute preserving maps" to category of abelian groups". Later, we define orthogonality of complete absolute preserving maps and prove that Grothendieck group" functor is additive on orthogonal unital completely absolute preserving maps.