Sudhir Ranjan Jain | |
---|---|
Nationality | Indian |
Alma mater | University of Delhi (B.Sc.) Indian Institute of Technology, Delhi (M.Sc.) University of Mumbai (Ph.D.) |
Scientific career | |
Fields | Nonlinear Dynamics, Nuclear Physics, Semiclassical physics, Dynamical billiards, Random Matrix Theory, Quantum chaos |
Institutions | Bhabha Atomic Research Centre Homi Bhabha National Institute Centre for Excellence in Basic Sciences |
Doctoral advisor | Suresh V. Lawande |
Sudhir Ranjan Jain (born 16 May 1963) is an Indian theoretical physicist [1] [2] [3] at the Bhabha Atomic Research Centre, Mumbai, known for his contributions in complex quantum systems and Nonlinear dynamics. He was a scientist at the nuclear physics division of Bhabha Atomic Research Centre, a professor at Homi Bhabha National Institute and is an adjunct professor and member of the Academic Board at the Centre for Excellence in Basic Sciences. He has authored Mechanics, Waves and Thermodynamics: An Example-based Approach and A Primer on Fluid Mechanics with Applications. [4] [5] His doctoral advisor was Prof. Suresh V. Lawande, [6] who was a student of Edward Teller. [7]
Sudhir Ranjan Jain was born in Mainpuri (Uttar Pradesh, India). He completed his bachelor's degree from Hindu College, Delhi, in 1983 and master's degree from Indian Institute of Technology, Delhi, in 1985. [8] He joined Bhabha Atomic Research Centre in 1986. Subsequently, he obtained his Ph.D. degree from University of Mumbai in 1994 under the guidance of Dr. Suresh V. Lawande. [9] He did post-doctoral research at Centre for Nonlinear Phenomena and Complex Systems, Université libre de Bruxelles, Belgium, with Pierre Gaspard, where he worked on semiclassics of many-body Fermionic systems. [10]
He has been a visiting professor at Feza Gürsey Institute, Istanbul, Turkey (2008), Institut Henri Poincaré, Paris, France (2007), Institute of Theoretical Physics, Utrecht University, Netherlands (2006) and Institute for Physical Science and Technology, University of Maryland, College Park (2005). [8]
Jain's areas of specialization are theoretical nuclear physics, [11] [12] [13] semiclassical physics, [14] and nonlinear dynamics. [15]
He is known for his work on many-body systems, especially for Jain-Khare models [16] [17] [18] which gave exact quantum solutions with connections to random matrix theory, leading to exact eigenfunctions for a class of chaotic systems. The bosonised version of the Jain-Khare model exhibits Bose Einstein condensation. [16]
His notable works include his work on Pseudo Hermitian Random Matrix theory, [19] relation of Random Matrix theory to anyon gases, [20] theorems and statistics for integrable billiards and nodal domains, [21] [22] [23] quantum modes built on chaotic motion, [24] Poincaré recurrence theorem in Kac's ring. [25] His work in neutrino physics pioneered in calculation of geometric phases in neutrinos. [26] [27]
Among other contributions, Jain made significant developments towards the exact semiclassical treatment of deuteron [28] which he further extended to nuclear three body problem of triton. [29] He developed an exact semiclassical trace formula to calculate level densities of spherical nuclei with no adjustable parameters. [30]
He has also worked on quantum computation and quantum information science. In particular, his work with his collaborators has led to an understanding of controlling quantum jump by realising "Dehmelt-like" shelving by employing quantum Zeno effect. [31] His work has contributed a non-topological code with highest encoding rate [32] and established protection of qubits using ideas from classical and quantum nonlinear science [33] [34] [35]
He was scientific secretary of the XXth Solvay Conference on Femtochemistry. [36] He was also the convenor of International conference on complex quantum systems in 2017, [37] 2020 and 2023. [38]
A quantum computer is a computer that exploits quantum mechanical phenomena. On small scales, physical matter exhibits properties of both particles and waves, and quantum computing leverages this behavior using specialized hardware. Classical physics cannot explain the operation of these quantum devices, and a scalable quantum computer could perform some calculations exponentially faster than any modern "classical" computer. Theoretically a large-scale quantum computer could break some widely used encryption schemes and aid physicists in performing physical simulations; however, the current state of the art is largely experimental and impractical, with several obstacles to useful applications.
This is a timeline of quantum computing.
Quantum chaos is a branch of physics focused on how chaotic classical dynamical systems can be described in terms of quantum theory. The primary question that quantum chaos seeks to answer is: "What is the relationship between quantum mechanics and classical chaos?" The correspondence principle states that classical mechanics is the classical limit of quantum mechanics, specifically in the limit as the ratio of the Planck constant to the action of the system tends to zero. If this is true, then there must be quantum mechanisms underlying classical chaos. If quantum mechanics does not demonstrate an exponential sensitivity to initial conditions, how can exponential sensitivity to initial conditions arise in classical chaos, which must be the correspondence principle limit of quantum mechanics?
Pieter Kok is a Dutch physicist and one of the co-developers of quantum interferometric optical lithography. His research specializations include linear optical implementations of quantum communication and computation protocols, quantum teleportation and the interpretation of quantum theory. He is a Professor of Theoretical Physics at the University of Sheffield.
Leonard Mlodinow is an American theoretical physicist and mathematician, screenwriter and author. In physics, he is known for his work on the large N expansion, a method of approximating the spectrum of atoms based on the consideration of an infinite-dimensional version of the problem, and for his work on the quantum theory of light inside dielectrics.
A trapped-ion quantum computer is one proposed approach to a large-scale quantum computer. Ions, or charged atomic particles, can be confined and suspended in free space using electromagnetic fields. Qubits are stored in stable electronic states of each ion, and quantum information can be transferred through the collective quantized motion of the ions in a shared trap. Lasers are applied to induce coupling between the qubit states or coupling between the internal qubit states and the external motional states.
Physics beyond the Standard Model (BSM) refers to the theoretical developments needed to explain the deficiencies of the Standard Model, such as the inability to explain the fundamental parameters of the standard model, the strong CP problem, neutrino oscillations, matter–antimatter asymmetry, and the nature of dark matter and dark energy. Another problem lies within the mathematical framework of the Standard Model itself: the Standard Model is inconsistent with that of general relativity, and one or both theories break down under certain conditions, such as spacetime singularities like the Big Bang and black hole event horizons.
A topological quantum computer is a theoretical type of quantum computer proposed by Russian-American physicist Alexei Kitaev in 1997. It utilizes quasiparticles, known as anyons, in two-dimensional systems. These anyons' world lines intertwine to form braids in a three-dimensional spacetime. These braids act as the logic gates of the computer. The primary advantage of using quantum braids over trapped quantum particles is enhanced stability. While small, cumulative perturbations can cause quantum states to decohere and introduce errors in traditional quantum computations, such perturbations do not alter the topological properties of the braids. This stability is akin to the difference between cutting and reattaching a string to form a different braid versus a ball colliding with a wall.
In quantum chaos, a branch of mathematical physics, quantum ergodicity is a property of the quantization of classical mechanical systems that are chaotic in the sense of exponential sensitivity to initial conditions. Quantum ergodicity states, roughly, that in the high-energy limit, the probability distributions associated to energy eigenstates of a quantized ergodic Hamiltonian tend to a uniform distribution in the classical phase space. This is consistent with the intuition that the flows of ergodic systems are equidistributed in phase space. By contrast, classical completely integrable systems generally have periodic orbits in phase space, and this is exhibited in a variety of ways in the high-energy limit of the eigenstates: typically, some form of concentration occurs in the semiclassical limit .
Vladimir E. Korepin is a professor at the C. N. Yang Institute of Theoretical Physics of the Stony Brook University. Korepin made research contributions in several areas of mathematics and physics.
Frank Verstraete is a Belgian quantum physicist who is working on the interface between quantum information theory and quantum many-body physics. He pioneered the use of tensor networks and entanglement theory in quantum many body systems. He holds the Leigh Trapnell Professorship of Quantum Physics at the Faculty of Mathematics, University of Cambridge, and is professor at the Faculty of Physics at Ghent University.
Circuit quantum electrodynamics provides a means of studying the fundamental interaction between light and matter. As in the field of cavity quantum electrodynamics, a single photon within a single mode cavity coherently couples to a quantum object (atom). In contrast to cavity QED, the photon is stored in a one-dimensional on-chip resonator and the quantum object is no natural atom but an artificial one. These artificial atoms usually are mesoscopic devices which exhibit an atom-like energy spectrum. The field of circuit QED is a prominent example for quantum information processing and a promising candidate for future quantum computation.
In quantum mechanics, quantum scarring is a phenomenon where the eigenstates of a classically chaotic quantum system have enhanced probability density around the paths of unstable classical periodic orbits. The instability of the periodic orbit is a decisive point that differentiates quantum scars from the more trivial observation that the probability density is enhanced in the neighborhood of stable periodic orbits. The latter can be understood as a purely classical phenomenon, a manifestation of the Bohr correspondence principle, whereas in the former, quantum interference is essential. As such, scarring is both a visual example of quantum-classical correspondence, and simultaneously an example of a (local) quantum suppression of chaos.
Quantum simulators permit the study of a quantum system in a programmable fashion. In this instance, simulators are special purpose devices designed to provide insight about specific physics problems. Quantum simulators may be contrasted with generally programmable "digital" quantum computers, which would be capable of solving a wider class of quantum problems.
Linear optical quantum computing or linear optics quantum computation (LOQC), also photonic quantum computing (PQC), is a paradigm of quantum computation, allowing (under certain conditions, described below) universal quantum computation. LOQC uses photons as information carriers, mainly uses linear optical elements, or optical instruments (including reciprocal mirrors and waveplates) to process quantum information, and uses photon detectors and quantum memories to detect and store quantum information.
The KLM scheme or KLM protocol is an implementation of linear optical quantum computing (LOQC) developed in 2000 by Emanuel Knill, Raymond Laflamme and Gerard J. Milburn. This protocol allows for the creation of universal quantum computers using solely linear optical tools. The KLM protocol uses linear optical elements, single-photon sources and photon detectors as resources to construct a quantum computation scheme involving only ancilla resources, quantum teleportations and error corrections.
Continuous-variable (CV) quantum information is the area of quantum information science that makes use of physical observables, like the strength of an electromagnetic field, whose numerical values belong to continuous intervals. One primary application is quantum computing. In a sense, continuous-variable quantum computation is "analog", while quantum computation using qubits is "digital." In more technical terms, the former makes use of Hilbert spaces that are infinite-dimensional, while the Hilbert spaces for systems comprising collections of qubits are finite-dimensional. One motivation for studying continuous-variable quantum computation is to understand what resources are necessary to make quantum computers more powerful than classical ones.
Randomized benchmarking is an experimental method for measuring the average error rates of quantum computing hardware platforms. The protocol estimates the average error rates by implementing long sequences of randomly sampled quantum gate operations. Randomized benchmarking is the industry-standard protocol used by quantum hardware developers such as IBM and Google to test the performance of the quantum operations.
Hamiltonian simulation is a problem in quantum information science that attempts to find the computational complexity and quantum algorithms needed for simulating quantum systems. Hamiltonian simulation is a problem that demands algorithms which implement the evolution of a quantum state efficiently. The Hamiltonian simulation problem was proposed by Richard Feynman in 1982, where he proposed a quantum computer as a possible solution since the simulation of general Hamiltonians seem to grow exponentially with respect to the system size.