Tag Archives: quantum

Postdoctoral Research Fellowship in Quantum Foundations

General Information

The Institute for Quantum Studies within Schmid College of Science and Technology at Chapman University invites applications for a Postdoctoral Research Fellow in the Foundations of Quantum Theory, beginning August 2018.

Chapman University, located in the heart of Orange County, California, is ranked in the top tier of western universities by U.S. News and World Report, and has gained national recognition for its commitment to excellence through innovative research and teaching. Schmid College of Science and Technology embodies Chapman’s commitment to interdisciplinarity, fostering an outstanding community of teacher-scholars across a broad range of undergraduate and graduate programs. More information on the College and its future 140,000 square foot home, the Keck Center for Science and Engineering, can be found here: www.chapman.edu/science.

Qualifications

Postdoctoral Fellow must hold a Ph.D. or an equivalent of a doctoral degree by the beginning of employment at Chapman University. The doctorate or equivalent must have been awarded within the last five years and candidate has not exceeded five years of prior postdoctoral experience.

A publication record showing a strong promise for future independent research is highly desirable.

Responsibilities

The postdoc will work in the group of Dr. Matthew Leifer on the project “Fine Tunings and the Nature of Quantum Reality”.

A “fine tuning” refers to a property of the operational predictions of quantum theory that cannot hold at the level of reality. Fine tunings are exposed by the various no-go theorems for realist accounts of quantum theory, such as Bell’s theorem, the Kochen-Specker theorem, and recent results on the reality of the quantum state. The project encompasses: rigorously defining the notion of a fine tuning, characterizing and quantifying fine-tunings in a resource theoretic framework, exploiting fine tunings for information processing advantages, developing ontological frameworks for quantum theory that are free of fine tunings, and explaining fine tunings as emergent.

The postdoc is expected to work with Dr. Leifer on this project, but may also pursue their own independent research.

The postdoc is expected to publish their findings in academic journals and present their work at academic conferences and workshops. The postdoc is also expected to contribute to the research culture of the institute and university. Examples of ways of doing this include: giving seminars, helping to organize conferences and workshops, helping to organize seminars and talks, and discussing research with undergraduate and graduate students who are working on research projects.

Contact Information

Applicants should send electronic copies of their CV, research statement, list of publications, and three references to Dr. Matthew Leifer at leifer@chapman.edu.

Applications should be received before December 7, 2017 in order to receive full consideration, but the position will remain open until filled.

Fellows are offered a competitive salary, benefits, research support, and personalized professional development in research.
Chapman University is an equal opportunity employer committed to fostering a diverse and inclusive academic global community. The University is dedicated to enhancing diversity and inclusion in all aspects of recruitment and employment. All qualified applicants will receive consideration for employment without regard to race, color, religion, age, sex, sexual orientation, gender identity, gender expression, national origin, ancestry, citizenship status, physical disability, mental disability, medical condition, military and veteran status, marital status, pregnancy, genetic information or any other characteristic protected by state or federal law. The University is committed to achieving a diverse faculty and staff and encourages members of underrepresented groups to apply.

Chapman University, One University Drive, Orange, CA 92866 Human Resources Department

Quantum Foundations at the APS March Meeting

The March Meeting of the American Physical Society is taking place March 5-9 2017 in Los Angeles. There will be sessions on Quantum Foundations, Quantum Resource Theories, and Quantum Thermodynamics. You can submit an abstract for a contributed talk at http://www.aps.org/meetings/march/. The deadline is November 3 at 11:59pm EST.

The APS March Meeting is a great opportunity to advertise recent work in quantum foundations to the wider physics community. I hope you will consider contributing a talk so that we can showcase our research in the strongest possible way.

Q+ Hangout: Howard Wiseman

Here are the details of the next Q+ hangout.

Date/time: Wed. 26th Nov. 2014 10pm GMT/UTC

Speaker: Howard Wiseman (Griffith University)

Title: After 50 years, Bell’s Theorem Still Reverberates

Abstract:
Fifty years ago this month, Belfast-born physicist John Bell submitted for publication a paper [1] which has been described as “the most profound discovery in science” [2]. However, its significance is still much disputed by physicists and philosophers [3, 4].
I will explain what is so puzzling about the types of correlations Bell introduced, by a specific example based on [5]. (For those well-versed in Bell inequalities this may still be of pedagogical interest.)
But what exactly do these Bell-type correlations violate? Bell’s original answer [1] was the joint assumptions of determinism and locality. His later answer [6] was the single assumption of local causality (which, confusingly, he sometimes also called locality). Different ‘camps’ of physicists – operationalists and realists respectively – prefer the different versions of Bell’s theorem.

Which of Bell’s notions, locality or local causality, expresses the causal structure of Einstein’s theory of relativity? I will argue for the answer: neither [3,4]. Both notions require an additional causal assumption, and the one required for local causality is a stronger one. I will discuss how the different assumptions fit with the ideologies of the two camps, and how they can best be reconciled.

[1]  J. S. Bell, “On the Einstein-Podolsky-Rosen paradox”, Physics 1, 195-200 (1964).
[2]  H. P. Stapp, “Are superluminal connections necessary?”, Nuovo Cim. 40B, 191 (1977).
[3]  H. M. Wiseman, “The two Bell’s theorems of John Bell”, J. Phys. A 47, 424001 (2014) (Invited Review for Special Issue, 50 years of Bell’s theorem)
[4]  H. M. Wiseman, “Bell’s theorem still reverberates”, Nature 510, 467-9 (2014).
[5] P. K. Aravind, “Bell’s theorem without inequalities and only two distant observers”,  Found. Phys. Lett. 15, 397 (2002).
[6]  J. S. Bell, “The Theory of Local Beables”, Epistemological Lett. 9, 11-24 (1976).

To watch the talk live, visit the event page at the appointed hour.

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Q+ Hangout: Marco Piani

Here are the details of the next Q+ hangout:

Date: Monday 27th October 2pm GMT/UTC

Spekaer: Marco Piani (University of Strathclyde)

Title: Usefulness of entanglement and steering in the discrimination of physical processes

Abstract: Not all entangled states are created equal: they are all special, but some are more special than others. In particular, this is true in an operational characterization of quantum correlations based on their usefulness in the discrimination of physical processes. We will discuss how every entangled state of a probe-ancilla composite system is useful as a resource for the problem of minimum-error channel discrimination. We will then focus on the subset of entangled states that exhibit steering. The latter is the entanglement-based quantum effect that embodies the “spooky action at a distance” disliked by Einstein and scrutinized by Einstein, Podolsky, and Rosen. We prove that, for any fixed steerable state, there are instances of a generalization of the channel discrimination problem, which we dub quantum subchannel discrimination, where such a state allows a correct discrimination with strictly higher probability than in absence of entanglement, even when measurements are restricted to local measurements aided by one-way communication. On the other hand, unsteerable states are useless under such a restriction, even when entangled. We also prove that the above steering advantage can be exactly quantified in terms of the steering robustness, which is a natural measure of the steerability exhibited by the state.
This talk is based on joint work with J. Watrous, arXiv:1406.0530.

To watch live, visit the hangout page at the appointed hour.

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Q+ Hangout: Daniel Gottesman

Here are the details of the next Q+ hangout. To watch live, visit this link at the appointed hour.

Date/time: Tue. May 20th 2014 2pm BST/UTC+1

Speaker: Daniel Gottesman (Perimeter Institute)

Title: Fault-tolerant quantum computation with constant overhead

Abstract: The threshold theorem for fault tolerance tells us that it is possible to build arbitrarily large reliable quantum computers provided the error rate per physical gate or time step is below some threshold value. Most research on the threshold theorem so far has gone into optimizing the tolerable error rate under various assumptions, with other considerations being secondary. However, for the foreseeable future, the number of qubits may be an even greater restriction than error rates. The overhead, the ratio of physical qubits to logical qubits, determines how expensive (in qubits) a fault-tolerant computation is. Earlier results on fault tolerance used a large overhead which grows even larger (albeit slowly) with the size of the computation. I show that it is possible in principle to do fault-tolerant quantum computation with the overhead constant in the size of the computation, and with a low constant at that. The result depends on recent progress on quantum low-density parity check codes.

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Q+ hangout: Chris Richardson

Here are the details of the next Q+ hangout.

Date/time: 22nd April 2014 2pm BST/UTC+1

Speaker: Chris Richardson (University of Liege)

Title: On the Uncertainty of the Ordering of Nonlocal Wavefunction Collapse when Relativity is Considered

Abstract: The temporal measurement order and therefore the originator of the instantaneous collapse of the wavefunction of a spatiality entangled particle pair can change depending on the reference frame of an observer. This can lead to a paradox in which its seems that both measurements collapsed the wavefunction before the other. We resolve this paradox by demonstrating how attempting to determine the order of measurement of the entangled pair introduces uncertainty which makes the measurement order impossible to know.

To watch the talk live, go to the event page at the appointed hour.

To keep up to date on the latest news about Q+ hangouts you can follow us on:

or visit our website.

Q+ Hangout: Mark Wilde

Here are the details of the next Q+ hangout.

Date/time: Tue. 26th Nov. 3pm GMT/UTC

Speaker: Mark Wilde (Louisiana State University)

Title: Strong Converse Theorems in Quantum Information Theory

Abstract: One of the main goals in quantum information theory is to establish the capacity of a quantum channel for communicating various kinds of information, whether it be bits or qubits. While several communication capacities of quantum channels are now known, the characterization of capacity in many of these cases is often limited to it being a threshold that determines the rates at which reliable communication is or is not possible. While this characterization might be satisfactory for some purposes, it leaves open the possibility for a trade-off between communication rate and error probability (that is, one might think that it would be possible to send data at a higher rate by allowing for errors to occur some of the time). However, we now know that such a trade-off is not possible for many channels and capacities of interest. That is, many researchers have now established that a strong converse theorem holds for several channels and capacities, so that as soon as the communication rate exceeds capacity, it is guaranteed that the error probability converges to one in the limit of large blocklength, no matter what strategy the sender and receiver employ. These strong converse theorems strengthen the interpretation and our understanding of capacity as a very sharp dividing line between rates for which asymptotically perfect communication is possible and rates for which an error is guaranteed to occur (analogous to a phase transition in statistical physics). This Q+ talk will review much of the progress in establishing strong converse theorems for several channels and their communication capacities in quantum information theory.

Joint work with Bhaskar Roy Bardhan (LSU Baton Rouge), Manish K. Gupta (LSU Baton Rouge), Naresh Sharma (TIFR Mumbai), Dong Yang (UAB Barcelona), and Andreas Winter (UAB Barcelona).

To watch the talk live, go to http://gplus.to/qplus at the appointed hour. To stay up to date on the latest news about Q+ hangouts you can follow us on:

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