Chennai Mathematical Institute


Today's Seminar
  • 21-01-21
    Thursday, 21 January 2021, 9 pm (IST)
    Partha Mukhopadhyay is inviting you to a scheduled Zoom meeting.
    Topic: Partha Mukhopadhyay's Zoom Meeting Time: Jan 21, 2021 08:30 PM Mumbai, Kolkata, New Delhi
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    Meeting ID: 860 6182 8564
    Passcode: 350528
    Quantum Logspace Algorithm for Powering Matrices with Bounded Norm
    Uma Girish
    Princeton University (USA).
    We give a quantum logspace algorithm for powering matrices with spectral norm at most 1. The algorithm gets as input an arbitrary n by n matrix A with spectral norm at most 1 and a parameter k <= poly(n) and outputs the entries of A^k up to (arbitrary) polynomially small additive error. We give several applications of this result to quantum computation without classical memory.

    Our results apply to quantum algorithms with purely quantum memory. We show that the class of quantum logspace algorithms with intermediate measurements is equivalent to the class of quantum logspace algorithms without intermediate measurements. This shows that the deferred-measurement principle, a fundamental principle in quantum computing also applies for quantum logspace algorithms. Since unitary transformations are reversible, while measurements are irreversible, an interesting aspect of this result is that any quantum logspace algorithm can be simulated by a reversible quantum logspace algorithm. Since the process of tossing random coins can be simulated using intermediate measurements, our result can also be viewed as a derandomization of quantum logspace algorithms.

    This is a joint work with Ran Raz and Wei Zhan.

Forthcoming Seminars
  • 22-01-21
    Date: 22-Jan-2021
    Time: 2:00 pm - 3:30 pm
    Data Science Seminar
    Venue: Zoom platform
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    Meeting ID: 836 0708 1074
    Passcode: 975169
    Role of statistics in the era of BigData, Analytics, Data Science(Abstract)
    Rajeeva L Karandikar
    Chennai Mathematical Institute.

  • 26-01-21
    Date: 26 Jan; Time : 9 pm.
    Topic: A talk by Ramya C.
    Time: Jan 26, 2021 9:00 PM Mumbai, Kolkata, New Delhi
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    Meeting ID: 860 6182 8564
    Passcode: 350528
    Algebraic Complexity Theory: A gripping tale of two polynomials(Abstract)
    Ramya C.

  • 28-01-21
    Thursday, January 28, 2021
    Time: 3:30 PM.
    Topic: CMI Mathematics Seminar
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    Meeting ID: 874 1459 3183
    Passcode: 486077
    positive cones of cycles on products of projective bundles over curves(Abstract)
    Rupam Karmakar
    Chennai Mathematical Institute.

Past Seminars (this year)
  • 08-01-21
    Data Science Seminar
    2:00 - 3:00 pm
    Join Zoom Meeting
    Meeting ID: 717 383 3479
    Passcode: 2377
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    Predictions, Role of Interventions and the Crisis of Virus in India: A Data Science Call to Arms(Abstract)
    Bhramar Mukherjee
    University of Michigan.