Jonathan Oppenheim | |
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Born | |
Alma mater | University of Toronto (BSc, 1993) University of British Columbia (PhD, 2000) |
Awards | Royal Society Wolfson Research Merit Award EPSRC Established Career Fellowship [2] |
Scientific career | |
Fields | quantum information theory quantum gravity |
Institutions | University College London University of Cambridge Racah Institute of Physics, The Hebrew University University of Alberta [2] |
Thesis | Quantum Time (2000) |
Doctoral advisor | Bill Unruh |
Website | www |
Jonathan Oppenheim is a professor of physics at University College London. He is an expert in quantum information theory and quantum gravity.
Oppenheim obtained a bachelor's degree at the University of Toronto in 1993 and PhD at the University of British Columbia in 2001. His PhD thesis titled Quantum Time, focused on time ordering in quantum mechanics and was supervised by Bill Unruh.
In 2004, he was a postdoctoral researcher under Jacob Bekenstein and a Royal Society University Fellow at the University of Cambridge before moving to University College London.
In 2005, together with Michał Horodecki and Andreas Winter, Oppenheim discovered quantum state-merging and used this primitive to show that quantum information could be negative. [3] Following on this work, Oppenheim and collaborators have developed a resource theory for thermodynamics on the nano and quantum scale. [4] [5]
In 2017, Oppenheim and Lluis Masanes derived the third law of thermodynamics using quantum information arguments and set a bound to the speed at which information can be erased. [6] [7]
Oppenheim published a proposal in 2023 for a hybrid theory that couples classical general relativity with quantum field theory. According to this proposal, spacetime is not quantized but smooth and continuous, and is subject to random fluctuations. [8] [9]
As a student, Oppenheim was involved in the Edible Ballot Society which satirically advanced eating ballots to highlight the democracy gap in electoral politics. [10] He was arrested at the 1997 APEC protests on University of British Columbia campus. [11] He withdrew from the Commission for Public Complaints Against the RCMP following the refusal of the Prime Minister to testify. [12] [13] His group was responsible for smuggling a siege catapult [14] into the medieval city of Quebec during the Summit of Americas, 2001. It was used to lob teddy bears. [15] [16] [17]
Quantum entanglement is the phenomenon of a group of particles being generated, interacting, or sharing spatial proximity in such a way that the quantum state of each particle of the group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics not present in classical mechanics.
In physics, black hole thermodynamics is the area of study that seeks to reconcile the laws of thermodynamics with the existence of black hole event horizons. As the study of the statistical mechanics of black-body radiation led to the development of the theory of quantum mechanics, the effort to understand the statistical mechanics of black holes has had a deep impact upon the understanding of quantum gravity, leading to the formulation of the holographic principle.
The conditional quantum entropy is an entropy measure used in quantum information theory. It is a generalization of the conditional entropy of classical information theory. For a bipartite state , the conditional entropy is written , or , depending on the notation being used for the von Neumann entropy. The quantum conditional entropy was defined in terms of a conditional density operator by Nicolas Cerf and Chris Adami, who showed that quantum conditional entropies can be negative, something that is forbidden in classical physics. The negativity of quantum conditional entropy is a sufficient criterion for quantum non-separability.
Pieter Kok is a Dutch physicist and one of the co-developers of quantum interferometric optical lithography.
An atom interferometer uses the wave-like nature of atoms in order to produce interference. In atom interferometers, the roles of matter and light are reversed compared to the laser based interferometers, i.e. the beam splitter and mirrors are lasers while the source emits matter waves rather than light. Atom interferometers measure the difference in phase between atomic matter waves along different paths. Matter waves are controlled an manipulated using systems of lasers. Atom interferometers have been used in tests of fundamental physics, including measurements of the gravitational constant, the fine-structure constant, and universality of free fall. Applied uses of atom interferometers include accelerometers, rotation sensors, and gravity gradiometers.
The Peres–Horodecki criterion is a necessary condition, for the joint density matrix of two quantum mechanical systems and , to be separable. It is also called the PPT criterion, for positive partial transpose. In the 2×2 and 2×3 dimensional cases the condition is also sufficient. It is used to decide the separability of mixed states, where the Schmidt decomposition does not apply. The theorem was discovered in 1996 by Asher Peres and the Horodecki family
The Born rule is a postulate of quantum mechanics that gives the probability that a measurement of a quantum system will yield a given result. In its simplest form, it states that the probability density of finding a system in a given state, when measured, is proportional to the square of the amplitude of the system's wavefunction at that state. It was formulated and published by German physicist Max Born in July, 1926.
Michał Horodecki is a Polish physicist at the University of Gdańsk working in the field of quantum information theory, notable for his work on entanglement theory.
Andreas J. Winter is a German mathematician and mathematical physicist at the Universitat Autònoma de Barcelona (UAB) in Spain. He received his Ph.D. in 1999 under Rudolf Ahlswede and Friedrich Götze at the Universität Bielefeld in Germany before moving to the University of Bristol and then to the Centre for Quantum Technologies (CQT) at the National University of Singapore. In 2013 he was appointed ICREA Research Professor at UAB.
In quantum information theory, quantum state merging is the transfer of a quantum state when the receiver already has part of the state. The process optimally transfers partial information using entanglement and classical communication. It allows for sending information using an amount of entanglement given by the conditional quantum entropy, with the Von Neumann entropy, . It thus provides an operational meaning to this quantity.
Paweł Horodecki is a Polish professor of physics at the Gdańsk University of Technology working in the field of quantum information theory. He is best known for introducing the Peres-Horodecki criterion for testing whether a quantum state is entangled. Moreover, Paweł Horodecki demonstrated that there exist states which are entangled whereas no pure entangled states can be obtained from them by means of local operations and classical communication (LOCC). Such states are called bound entangled states. He also showed that even bound entanglement can lead to quantum teleportation with a fidelity impossible to achieve with only separable states.
In quantum information theory, quantum discord is a measure of nonclassical correlations between two subsystems of a quantum system. It includes correlations that are due to quantum physical effects but do not necessarily involve quantum entanglement.
Stephanie Dorothea Christine Wehner is a German physicist and computer scientist.
Sandu Popescu is a Romanian-British physicist working in the foundations of quantum mechanics and quantum information.
Stochastic thermodynamics is an emergent field of research in statistical mechanics that uses stochastic variables to better understand the non-equilibrium dynamics present in many microscopic systems such as colloidal particles, biopolymers, enzymes, and molecular motors.
The Eastin–Knill theorem is a no-go theorem that states: "No quantum error correcting code can have a continuous symmetry which acts transversely on physical qubits". In other words, no quantum error correcting code can transversely implement a universal gate set, where a transversal logical gate is one that can be implemented on a logical qubit by the independent action of separate physical gates on corresponding physical qubits.
Bound entanglement is a weak form of quantum entanglement, from which no singlets can be distilled with local operations and classical communication (LOCC).
Gravitational decoherence is a term for hypothetical mechanisms by which gravitation can act on quantum mechanical systems to produce decoherence. Advocates of gravitational decoherence include Frigyes Károlyházy, Roger Penrose and Lajos Diósi.
The entanglement of formation is a quantity that measures the entanglement of a bipartite quantum state.
Robert W. Spekkens is a Canadian theoretical quantum physicist working in the fields of quantum foundations and quantum information.