aspuru-list February 2015

aspuru-list@lists.fas.harvard.edu

19 participants
48 discussions

[Aspuru-Guzik group list] [IACS-events] IACS Seminar on "Connectomics: extracting neural connectivity from very large data sets"------ FRIDAY 2/13 @1pm

by Baker, Natasha

Date: Friday, February 13, 2015 Location: Maxwell Dworkin G115, 33 Oxford Street, Cambridge MA 02138 Speakers: Ray Jones, IACS Lecturer Time: Lunch 12:30pm; talk 1:00pm Title: Connectomics: extracting neural connectivity from very large data sets Abstract: Connectomics is the study of neural connectivity. Using images from electron microscopes, we automatically identify nanometer-scale structures in microtomed brain tissue. We work with slices and images at a resolution where a cubic sample one millimeter on a side produces more than one petabyte of image data. To deal with such large datasets requires a mostly-automated approach. Our analysis pipeline uses computer vision, machine learning, and cluster computing to produce an initial version of the connectome within a sample. We then use a web-based proofreading and annotation tool to allow multiple simultaneous users to explore and correct the data within the volume. Free and open to the public. No registration required. *********************** UPCOMING SEMINARS 2/20 Delaney Granizo-Mackenzie (Quantopian) on "Free Software in Finance" 3/13 Alan Aspuru-Guzik (Harvard University) 3/27 Jeff Bilmes (University of Washington) 4/10 Budhendra Bhaduri (Oak Ridge National Laboratory--- Geographic Information Science and Technology) 4/24 Christian Rudder (OkCupid) Click here<https://lists.seas.harvard.edu/mailman/listinfo/iacs-events> to subscribe to our events list. _______________________________________________ Iacs-events mailing list Iacs-events(a)seas.harvard.edu https://lists.seas.harvard.edu/mailman/listinfo/iacs-events

9 years, 2 months

[Aspuru-Guzik group list] TODAY at 4:00 PM! Eugene Polzik - HQOC/ITAMP Joint Quantum Sciences Seminar

by Coleman, Karl

HQOC/ITAMP Joint Quantum Sciences Seminar Wednesday, February 11, 2015 4:00 PM, Jefferson 250 Eugene Polzik – Niels Bohr Institute, University of Copenhagen Measurements Beyond the Heisenberg Uncertainties Some operations on quantum states are not restricted by the Heisenberg uncertainty principle. One example is teleportation, which allows for both the position and the momentum be transferred without added noise [1]. Perhaps even more surprisingly, a trajectory of an oscillator can be measured with an accuracy exceeding the Heisenberg uncertainty in both position and momentum following the approach we have recently developed [2]. The key feature is to monitor the oscillator trajectory in a quantized reference frame with a negative mass with which the oscillator is entangled. In the talk I will first present a magnetic spin oscillator with an effective negative mass and report the results of tracing the oscillator trajectory and entanglement- assisted measurements of magnetic field [3]. I will then describe experimental progress towards tracing a trajectory of a mechanical oscillator with the precision not restricted by the Heisenberg uncertainty principle following the proposal [4]. 1. H. Krauter et al. Nature Phys., 9, 400 (2013). 2. E.S. Polzik and K. Hammerer, Ann. Phys. (Berlin) 527, No. 1–2, A15–A20 (2015). 3. G. Vasilakis et al, to appear in Nature Phys.; W. Wasilewski et al. Phys. Rev. Lett., 104, 133601 (2010). 4. K. Hammerer, M. Aspelmeyer, E.S. Polzik, P. Zoller. Phys. Rev. Lett. 102, 020501 (2009). Peter Komar, 10-Minute Speaker Entangling Optical Clocks via Rydberg Blockade Postdoc Presentation begins at 4:00 PM Refreshments are served from 4:10-4:30 PM Guest Presentation begins at 4:30 PM Karl Coleman HQOC Laboratory Administrator Faculty Assistant to Profs. Greiner and Lukin Harvard University Department of Physics 17 Oxford Street Cambridge, MA 02138 P: (617) 496-2544 F: (617) 496-2545

9 years, 2 months

[Aspuru-Guzik group list] Prof. Pablo Debenedetti Visiting

by Sawaya, Nicolas

Hi friends, Prof. Pablo Debenedetti (say it four times fast!) of Princeton will be giving the Theochem talk on Wednesday, February 11 (at MIT). He'll be visiting Harvard in the afternoon on Tuesday Feb 10. His research (http://www.princeton.edu/cbe/people/faculty/debenedetti/) involves the following topics: * Modeling sustainable energy technology (fuel cells, gas hydrates, fusion energy) * Water and aqueous solutions * Thermodynamics and stat mech of liquids, mixtures, and glasses (supercooled liquids/glasses) * Origins of life (origins of biological homochirality) Please let me know if you would like to meet with him. If you meet with him, you get a priority spot for dinner that night in H Sq. There are fewer spots than usual, because he won't arrive at Harvard until mid-afternoon. There may be additional meeting spots at MIT on Wednesday though. Cheers, Nicolas

9 years, 2 months

[Aspuru-Guzik group list] An interesting twist for photosynthetic life

by Semion Saikin

en.wikipedia.org/wiki/Elysia_chlorotica -- ******************************************** Semion K. Saikin, PhD Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street, Cambridge, MA 02138 email: saykin(a)fas.harvard.edu phone: (619)212-6649 ********************************************

9 years, 2 months

[Aspuru-Guzik group list] 02/11/2015 Eugene Polzik - HQOC/ITAMP Joint Quantum Sciences Seminar, 4PM

by Coleman, Karl

HQOC/ITAMP Joint Quantum Sciences Seminar Wednesday, February 11, 2015 4:00 PM, Jefferson 250 Prof. Eugene Polzik, University of Copenhagen Measurements Beyond The Heisenberg Uncertainties Some operations on quantum states are not restricted by the Heisenberg uncertainty principle. One example is teleportation, which allows for both the position and the momentum be transferred without added noise [1]. Perhaps even more surprisingly, a trajectory of an oscillator can be measured with an accuracy exceeding the Heisenberg uncertainty in both position and momentum following the approach we have recently developed [2]. The key feature is to monitor the oscillator trajectory in a quantized reference frame with a negative mass with which the oscillator is entangled. In the talk I will first present a magnetic spin oscillator with an effective negative mass and report the results of tracing the oscillator trajectory and entanglement assisted measurements of magnetic field [3]. I will then describe experimental progress towards tracing a trajectory of a mechanical oscillator with the precision not restricted by the Heisenberg uncertainty principle following the proposal [4]. 1. H. Krauter et al. Nature Phys., 9, 400 (2013). 2. E.S. Polzik and K. Hammerer, Ann. Phys. (Berlin) 527, No. 1–2, A15–A20 (2015). 3. G. Vasilakis et al, to appear in Nature Phys.; W. Wasilewski et al. Phys. Rev. Lett., 104, 133601 (2010). 4. K. Hammerer, M. Aspelmeyer, E.S. Polzik, P. Zoller. Phys. Rev. Lett. 102, 020501 (2009). Peter Komar, Lukin Lab Entangling optical clocks via Rydberg blockade Postdoc Presentation begins at 4:00 PM Refreshments are served from 4:10-4:30 PM Guest Presentation begins at 4:30 PM Karl Coleman HQOC Laboratory Administrator Faculty Assistant to Profs. Greiner and Lukin Harvard University Department of Physics 17 Oxford Street Cambridge, MA 02138 P: (617) 496-2544 F: (617) 496-2545

9 years, 2 months

[Aspuru-Guzik group list] Special Group Meeting Today at 1:30: Dr James Shepherd

by Thomas Markovich

Hi Everyone, As some of you may know, Dr James Shepherd has been spending some time with us over the last week. He will be giving us a group meeting at 130 in the Division Room, where he'll tell us a little about what he's recently been working on. I've attached his abstract below. Best, Thomas Abstract: Will coupled cluster theory work for correlated electrons in metals? The outcome of chemical reactions, such as those on the surface of metal catalysts, can depend on competition between electronic energies that differ by 1 mHa - 1/1000th the electron binding energy in a hydrogen atom. An approach commonly taken by quantum chemists is the use of coupled cluster theory - a wave function approach that goes beyond mean field theories in its treatment of electron correlation. Pioneering work has recently shown that high accuracy calculations are already possible for molecular crystals and insulators. However, as band gaps close, many approximate electronic structure methods are known to fail. This talk discusses how we might make coupled cluster theory work for metals.

9 years, 2 months

[Aspuru-Guzik group list] [IACS-events] REMINDER: IACS Seminar on "Orderly Randomness: Quasirandom Numbers and Quasi–Monte Carlo"------ TODAY, FRIDAY 2/6 @1pm

by Baker, Natasha

Date: Friday, February 6, 2015 Location: Maxwell Dworkin G115, 33 Oxford Street, Cambridge MA 02138 Speakers: Brian Hayes, IACS Associate Time: Lunch 12:30pm; talk 1:00pm Title: Orderly Randomness: Quasirandom Numbers and Quasi–Monte Carlo Abstract: Modern computing has an insatiable appetite for randomness. Cryptography and other kinds of adversarial computation demand “true” random numbers, which have three key properties: They are unpredictable, uncorrelated, and unbiased. Most other applications rely on pseudorandom numbers, which give up unpredictability but are still uncorrelated and unbiased. A third kind of randomness is even weaker. Quasirandom numbers are neither unpredictable nor uncorrelated; they claim only to be unbiased. They don’t even “look” random. Nevertheless, in some circumstances quasirandom numbers seem to be superior to pseudorandom ones. For example, they allow faster convergence or better error bounds in certain Monte Carlo simulations. Although quasirandom numbers have been known since the 1950s, some of their useful properties have been recognized only in the past few years, and they are not yet fully understood. Free and open to the public. No registration required. Speaker Bio: Brian Hayes is Senior Writer and columnist for American Scientist magazine and an Associate of SEAS. He writes mainly on mathematical and computational themes both for American Scientist and for his weblog bit-player.org<http://bit-player.org/>. In the 1970s and 80s he was an editor of Scientific American, and later he edited American Scientist. He has been a visitor at the Mathematical Sciences Research Institute in Berkeley and at the International Centre for Theoretical Physics in Trieste. A collection of Hayes’s columns, titled Group Theory in the Bedroom, and Other Mathematical Diversions<http://grouptheoryinthebedroom.com/>, was published by Hill and Wang in 2008. He is also the author of Infrastructure: A Guide to the Industrial Landscape<http://industrial-landscape.com/index.html> (W. W. Norton, 2005; second edition 2014). *********************** UPCOMING SEMINARS 2/13 Ray Jones (IACS Lecturer) on "Connectomics: extracting neural connectivity from very large data sets" Click here<https://lists.seas.harvard.edu/mailman/listinfo/iacs-events> to subscribe to our events list. _______________________________________________ Iacs-events mailing list Iacs-events(a)seas.harvard.edu https://lists.seas.harvard.edu/mailman/listinfo/iacs-events

9 years, 2 months

[Aspuru-Guzik group list] ITAMP lunch seminar: Kristin Beck (2/6)

by Singh, Swati

Dear colleagues, This week we are looking forward to a talk by Kristin Beck, who is currently a graduate student in Vuletić group. Kind regards, Richard and Swati *--------------* *ITAMP Topical Lunch Discussion* Date: Friday, Feb. 6th Time: 12:00-1:30 pm Pizza will be served. Location: B-106 @ Center for Astrophysics (60 Garden Street) Directions: after entering the lobby of the CfA, turn right to enter the hallway of the B building. In the hallway, turn right again, and B-106 is there. *Speaker: *Kristin Beck- Friday, 2/4 *Title: *Cross Modulation and Nondestructive Detection of Individual Photons *Abstract: *Deterministic interactions between individual photons are a building block for optical quantum information, simulation and communication schemes. In this talk, I will present two recent experiments in which we create and study such interactions. In our system, we send photons ('EIT photons') through an ensemble of cesium atoms, where they travel as slow-light polaritons. These atoms are, in turn, coupled to a high finesse optical cavity. The atomic component of the polariton changes the transmission of light through the cavity ('cavity photons'). In the first experiment, we demonstrate the mutual cross modulation of EIT and cavity photons. Here, the polariton's presence blocks cavity light. We observe that the two initially uncorrelated beams become anticorrelated with an equal-time cross-correlation function g2(0)=0.89(1). One photon extinguishes another with a probability of 11(1)% [1]. In the second experiment, we show that the system can be used to continuously detect photons without destroying them. The polariton's presence now changes the polarization of the light transmitted through the cavity. In the correct polarization basis, the EIT and cavity photons become correlated and we measure g2(0)=6(1). [1] K. Beck, W. Chen, Q. Lin, M. Gullans, M. D. Lukin, V. Vuletic, Phys. Rev. Lett. 113, 113603 (2014) -- Dr. Swati Singh Institute for Theoretical Atomic, Molecular, and Optical Physics (ITAMP), Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-14, Cambridge, MA 02138 https://www.cfa.harvard.edu/~ssingh/

9 years, 2 months

[Aspuru-Guzik group list] [qip] talks on Thursday (4pm) and Friday (1:30pm)

by aram harrow

Dear quanta, These two talks should be of interest to many of us. -------------- Thurs 2/5, 4pm in 10-250 Markus Oberthaler (University of Heidelberg) Quantum metrology with Bose Einstein Condensates One aspect of metrology, the science of measurement, is the exploration of the ultimate precision limit. It is known for quite some time that the new possibilities in quantum mechanics allow the surpassing of the ultimate classical precision limit given by counting statistics. Quantum metrology is about the exploration of these new limits. The goal is the generation and characterization of useful quantum mechanical resources for going beyond the classical precision limits. Since the gain in precision is intimately connected to quantum entanglement in many particle systems these investigations are also interesting from the fundamental point of view. In this colloquium I will discuss in detail how Bose Einstein condensates can be used to generate entangled many particle states which push atom interferometry beyond the classical limits. I will use the system of two component atomic condensates as a model system for explaining how quantum correlations arise and how they can be used for improved estimation of a phase shift in an atom interferometer. The simplest form of useful many particle quantum states are spin squeezed states which can be classified as Gaussian states. I will also report on the latest results revealing that Bose Einstein condensates make it possible to generate deterministically non-gaussian states. The experimental extraction of a bound of the quantum Fisher information implies that these states also surpass the classical limits of the phase estimation precision. ------------------- Fri 2/6, 1:30 in 6C-442 Brian Swingle (Stanford University) Einstein's Equations From Entanglement I will propose a mechanism whereby a dynamical geometry obeying Einstein's equations emerges holographically from entanglement in certain quantum many-body systems. As part of this broader story I will discuss in particular two crucial results: one establishing a geometric representation of entanglement in the vacuum state of a wide class of (lattice regulated) quantum field theories and one showing how the equivalence principle of gravity is encoded in the universality of entanglement. I will also briefly indicate how the first result opens the door to solving previously intractable strongly interacting models of relevance for experiments in the solid state and elsewhere. Thus I will argue that the fundamental physics of entanglement provides a window into non-perturbative quantum field theory and quantum gravity. ----------------- _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

9 years, 2 months

[Aspuru-Guzik group list] [qip] Friday the 6th

by Edward Farhi

Hi Quanta We will have our first meeting of the term on Friday the 6th at 11:00 in 6-310. I will be there! All of you who went to Sydney should come prepared to report on what you learned. Best, Eddie *********************************************** Edward Farhi Cecil and Ida Green Professor of Physics Director Center for Theoretical Physics Massachusetts Institute of Technology 6-300 Cambridge MA 02139 617 253 4871 *********************************************** _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

9 years, 2 months

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aspuru-list February 2015