aspuru-list July 2014

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34 participants
56 discussions

[Aspuru-Guzik group list] [qip] Special Seminar Wednesday - David Gross

by Cyril Stark

Hi Everybody, This Wednesday we have an exciting special seminar given by David Gross. Please find title and abstract below. Note that David will be speaking in the seminar room 6-310 (6C-442 is not available). Hope to see you there. Best, Cyril Title: Low-rank methods: From single pixel cameras to quantum state tomography Abstract: Every time the release button of a digital camera is pressed, several megabytes of raw data are recorded. But the size of a typical jpeg output file is only 10% of that. What a waste! Can't we design a process which records only the relevant 10% of the data to begin with? The theory of compressed sensing achieves this trick for sparse signals. A basis-independent notion of "sparsity" for a matrix is its rank. One is thus naturally led to the "low-rank matrix recovery" problem: can one reconstruct an unknown low-rank matrix from few linear measurements? Applications can be found in areas as diverse as face recognition, the analysis of x-ray diffraction images, and quantum state estimation. I will give an introduction to this field and emphasize how methods originally developed in quantum physics proved well-suited to the theory. -- Cyril Stark Center for Theoretical Physics Massachusetts Institute of Technology 77 Massachusetts Ave, 6-304 Cambridge, MA 02139, USA _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

9 years, 9 months

[Aspuru-Guzik group list] FW: Laptop Registration with HUPD

by Guerreschi, Gian

It's happening right now in room Cv233. G ________________________________ From: ccb_postdocs-bounces(a)lists.fas.harvard.edu [ccb_postdocs-bounces(a)lists.fas.harvard.edu] on behalf of Aloise, Allen [aloise(a)chemistry.harvard.edu] Sent: Friday, July 18, 2014 3:28 PM To: #List-CCB-Gradstudents; #List-CCB-PostDocs; #List-CCB-OtherGradStudents Cc: #List-CCB-Staff Subject: Re: [Postdocs] Laptop Registration with HUPD Dear CCB Researchers, Please see below for an explanation of how the new Lojack system will protect your laptop in the event of theft: LoJack for Laptops New this fall the Harvard University Police Department, in partnership with Absolute Software, will be offering LoJack for Laptops, a theft recovery system to students, faculty, and staff at Harvard University. Lo Jack for Laptops is a software-based theft recovery and data security service that is embedded into a computer's basic input/output system (BIOS) and installed onto the hard drive of the computer system. In the event that a laptop is lost or stolen, LoJack for Laptops can track, locate, and recover laptops. Once located Absolute Software will work with the local police department to recover the laptop. In addition to assisting in recovering the laptop, owners have the ability to remotely lock their computer and delete files, providing persons with the ability to protect personal information against identity theft. A four year (4) subscription costs $20. (CCB will cover this cost.) For more information on how to register your laptop or to find out when a registration fair will be held please contact lojackforlaptops(a)harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:lojackforlaptops%4…>. Learn more about Absolute Softwares LoJack for laptops<https://urldefense.proofpoint.com/v1/url?u=http://www3.absolute.com/lojackf…>. Amy Lieutenant Amy Di Virgilio R.A.D. Program Coordinator Harvard University Police Department 1033 Massachusetts Avenue Sixth Floor Cambridge, MA. 02138 617-495-1879 amy_divirgilio(a)hupd.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:amy_divirgilio%40h…> www.hupd.harvard.edu<http://www.hupd.harvard.edu/> From: <Aloise>, Allen Aloise <aloise(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:aloise%40chemistry…>> Date: Friday, July 18, 2014 at 2:13 PM To: #List-CCB-Gradstudents <gradstudents(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:gradstudents%40che…>>, #List-CCB-PostDocs <postdocs(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:postdocs%40chemist…>>, #List-CCB-OtherGradStudents <othergradstudents(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:othergradstudents%…>>, #List-CCB-Faculty <faculty(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:faculty%40chemistr…>> Cc: #List-CCB-Staff <staff(a)chemistry.harvard.edu<https://urldefense.proofpoint.com/v1/url?u=http://mailto:staff%40chemistry.…>> Subject: [CCB_Staff] Laptop Registration with HUPD Dear CCB Researchers, On Monday, July 21 between 10-11AM an officer from HUPD will be here at CCB registering laptop computers with the security Lojack tag for anyone who would like this service. If you would like to have your laptop secured and registered with HUPD, please visit Converse 233 with your laptop and your HUID. CV233 is the conference room located just before the mailroom on the 2nd floor. The Department will cover the cost of this for you! Many thanks to Nicole Minotti for arranging this service for CCB. Best, Allen --------------------------------------------------------------------- Allen Aloise, Ph.D. Director of Laboratories Co-Director of Graduate Studies Department of Chemistry and Chemical Biology (CCB) Harvard University 12 Oxford St. Cambridge, MA 02138 617-495-4283 (office) 617-496-5618 (fax) aloise(a)chemistry.harvard.edu<UrlBlockedError.aspx>

9 years, 9 months

[Aspuru-Guzik group list] [qip] Umesh Vazirani's talks

by Ramis Movassagh

Hi all, During the group meeting there was a confusion about when is Umesh Vazirani's talk. So there are two talks that were forwarded by Eddie and Aram before: Talk 1: --------- How "Quantum" is the D-Wave Machine? Umesh Vazirani (Berkeley) Tuesday, July 22, 2014 from 1:30-3pm, Microsoft Research (Barton room, 1st floor), One Memorial Drive. Talk 2: --------- Area Laws and the complexity of quantum states Umesh Vazirani (Berkeley) Thursday, July 24, 2014 from 3pm-4:30pm, Microsoft Research (Barton Room, 1st floor), One Memorial Drive. Best, -- Ramis _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

9 years, 9 months

[Aspuru-Guzik group list] Thursday Meeting with FAS RC

by Martin Blood-Forsythe

Dear colleagues, I have arranged a meeting with a few members of FAS RC for Thursday, July 24th during our usual group meeting slot in the Division Room to discuss best practices for the apsuru-guzik SLURM partition and what we can do to improve the compute experience. Unfortunately this timing is in direct conflict with Dmitrij's discussion session, but I wanted to make use of the existing booking of the division room and the knowledge that this day & time works for most of the group. Resolving poor performance and poor usage of our compute queue is a pretty important issue! I hope that many of you can attend. Best, -Martin

9 years, 9 months

[Aspuru-Guzik group list] Queue in Odyssey

by Guerreschi, Gian

Dear all, I forgot to discuss this topic in yesterday's group meeting, so I opted for a brief email. I sent a couple of (pretty light) jobs in Odyssey (in the Aspru-Guzik queue) and they are still pending since 1 week. Do you also experienced similar problems? Is there something wrong or is our partition of Odyssey massively overloaded? Further info: In the reason of the pending it is written "priority". Perhaps a solution is increasing the priority of my jobs? All the best, Giangi

9 years, 9 months

[Aspuru-Guzik group list] Fwd: Re: Queue in Odyssey

by Jarrod

Okay I know this thread is longer than most people's interest(and I promise this is my last email), but Salvatore has done some excellent sleuthing and determined the exact formula(including our particular parameters) by which our jobs are given priority. Anyone who runs on the cluster should find this extremely relevant, and it can form the basis for in-person discussions (as suggested by Tim) on cluster refinements for general satisfaction: -------- Original Message -------- Subject: Re: [Aspuru-Guzik group list] Queue in Odyssey Date: Fri, 18 Jul 2014 12:30:18 -0400 From: Salvatore Mandrà <salvatore.mandra(a)gmail.com> To: Jarrod <jarrod.mcc(a)gmail.com> Backfill functionality is a separate issue from the primary scheduler being FIFO(basic) vs fairshare(multifactor), are you able to check that as well? Sure! You were right, multifactor option is activated: $ cat /etc/slurm/slurm.conf | grep PriorityType PriorityType=priority/multifactor Looking at the documentation, the ranking of a job is defined as: Job_priority = (PriorityWeightAge) * (age_factor) + (PriorityWeightFairshare) * (fair-share_factor) + (PriorityWeightJobSize) * (job_size_factor) + (PriorityWeightPartition) * (partition_factor) + (PriorityWeightQOS) * (QOS_factor) All of the factors in this formula are floating point numbers that range from 0.0 to 1.0. In our case: PriorityWeightAge=1000 PriorityWeightFairshare=20000000 PriorityWeightJobSize=0 PriorityWeightPartition=100000000 PriorityWeightQOS=1000000000 where (https://computing.llnl.gov/linux/slurm/priority_multifactor.html#mfjppintro) *Age:* the length of time a job has been waiting in the queue, eligible to be scheduled *Fair-share:* the difference between the portion of the computing resource that has been promised and the amount of resources that has been consumed *Job size:* the number of nodes a job is allocated *Partition:* a factor associated with each node partition *QOS:* a factor associated with each Quality Of Service I guess that the job-dependent factors are: age, fair-share and job size (while partition and qos factors are jobs independent). As you can see, age seems to be not so important and it's dominated by the fair-share factor. --------------------------------------------------------- _Some analysis:_ *Age Factor* The age factor represents the length of time a job has been sitting in the queue and eligible to run. In general, the longer a job waits in the queue, the larger its age factor grows. However, the age factor for a dependent job will not change while it waits for the job it depends on to complete. Also, the age factor will not change when scheduling is withheld for a job whose node or time limits exceed the cluster's current limits. At some configurable length of time (PriorityMaxAge), the age factor will max out to 1.0. In our case, *PriorityMaxAge = 7-0*. This means that after 7 days (Am I right?), a job get a factor 1.0 in AgeFactor. *Fair-share Factor* The fair-share component to a job's priority influences the order in which a user's queued jobs are scheduled to run based on the portion of the computing resources they have been allocated and the resources their jobs have already consumed. The fair-share factor does not involve a fixed allotment, whereby a user's access to a machine is cut off once that allotment is reached. Instead, *the fair-share factor serves to prioritize queued jobs such that those jobs charging accounts that are under-serviced are scheduled first, while jobs charging accounts that are over-serviced are scheduled when the machine would otherwise go idle*. SLURM's fair-share factor is a floating point number between 0.0 and 1.0 that reflects the shares of a computing resource that a user has been allocated and the amount of computing resources the user's jobs have consumed. The higher the value, the higher is the placement in the queue of jobs waiting to be scheduled. The *computing resource* is currently defined to be computing cycles delivered by a machine in the units of *processor*seconds*. Future versions of the fair-share factor may additionally include a memory integral component. --------------------------------------------------------- Since the age_factor is really small compared to the fair-share factor, it is possible that jobs with a large fair-share factor could be served before than older jobs. Cheers! S

9 years, 9 months

[Aspuru-Guzik group list] AAG Lab Construction - Walk-About - 7/24/14

by Marlon Cummings

Dear friends: Next Thursday at 2:30PM, members of FAS and construction managers will take a tour of all our offices to look at the project spaces. They will be poking into each space, probably not spending more than 10-15 minutes. Hopefully they will conclude by the time the group meeting is over. Thanks, Marlon. ----------- Marlon G. Cummings Lab Manager, Aspuru-Guzik Group Mallinckrodt M112 Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge, MA 02138 617-496-9964 617-496-9411 (fax) http://aspuru.chem.harvard.edu/

9 years, 9 months

[Aspuru-Guzik group list] Fwd: Job opportunity

by Rafa Gómez Bombarelli

Hi All, An amazingly long 5-year postdoc on the other side of the pond for the more quantum-oriented. Maybe you know someone who could be interested. Cheers Rafa ---------- Forwarded message ---------- From: Brendon Lovett <bwl4(a)st-andrews.ac.uk> Date: 2014-07-17 11:54 GMT-04:00 Subject: Job opportunity To: Dear Colleagues, I am advertising a five year post-doc position here in St Andrews and I would greatly appreciate it if you could pass it to anyone who might be interested in applying for it. Details can be found here: https://www.vacancies.st-andrews.ac.uk/ViewVacancy.aspx?enc=mEgrBL4XQK0+ld8… best wishes, Brendon Group website: http://www.st-andrews.ac.uk/~bwl4 ============================================== Dr Brendon Lovett Royal Society University Research Fellow SUPA School of Physics and Astronomy University of St Andrews KY16 9SS tel: ++44 1334 463107 email: bwl4(a)st-andrews.ac.uk ==============================================

9 years, 9 months

[Aspuru-Guzik group list] Away July 18-28

by Cynthia M. Chew

Hi Group, I'll be away on vacation from July 18-28 and will not be checking e-mail. Please talk to Marlon if you have any requests in the meantime. See you in a bit! Cheers, Cynthia Cynthia M. Chew Faculty Assistant | Aspuru-Guzik Research Group Department of Chemistry and Chemical Biology | Harvard University 12 Oxford Street | Mallinckrodt 112 | Cambridge, MA 02138 617.496.1716 office | 617.496.9411 fax http://aspuru.chem.harvard.edu/

9 years, 9 months

[Aspuru-Guzik group list] [qip] Fwd: [Theory-reading-group] Fwd: [Toc-faculty] (2nd) Seminar at MSR: Umesh Vazirani on Area Laws and the complexity of quantum states

by aram harrow

See below for another talk by Vazirani, partly similar to the one he gave in our quantum info seminar, plus part on some work that I'm involved in. ---------- Forwarded message ---------- From: Madhu Sudan <madhu(a)mit.edu> Date: Wed, Jul 16, 2014 at 10:48 PM Subject: [Theory-reading-group] Fwd: [Toc-faculty] (2nd) Seminar at MSR: Umesh Vazirani on Area Laws and the complexity of quantum states To: theory-reading-group(a)csail.mit.edu Another talk by Umesh Vazirani next week. Madhu -------- Original Message -------- Subject: [Toc-faculty] (2nd) Seminar at MSR: Umesh Vazirani on Area Laws and the complexity of quantum states Date: Wed, 16 Jul 2014 17:48:10 -0400 From: Madhu Sudan <madhu(a)MIT.EDU> <madhu(a)MIT.EDU> To: toc-faculty <toc-faculty(a)csail.mit.edu> <toc-faculty(a)csail.mit.edu>, toc-students(a)csail.mit.edu, toc-visitors(a)csail.mit.edu Hi All Below is are the details of the second talk by Umesh Vazirani. This talk is aimed as a TCS audience. Madhu -------------------------------------------------------------------- Area Laws and the complexity of quantum states Umesh Vazirani (Berkeley) Thursday, July 24, 2014 from 3pm-4:30pm, Microsoft Research (Barton Room, 1st floor), One Memorial Drive. One of the great challenges posed by the laws of quantum mechanics is that the complexity of quantum states in general grows exponentially in the number of particles. This complexity is directly related to the phenomenon of quantum entanglement, the quantum analog of correlations. Finding an effective and succinct description for a quantum state may be compared to the analogous problem in machine learning of finding succinct and effective descriptions for probability distributions. Are there large classes of quantum states that do not suffer from exponential complexity? A sweeping conjecture, called the area law, asserts that states of special interest in condensed matter physics, ground states of gapped local Hamiltonians have limited entanglement. One might even very roughly say that this is what makes it possible to do quantum many body physics. Whereas the area law is rigorously proved for a one dimensional chain of particles, establishing it for two and three dimensional systems remains a central open question in quantum Hamiltonian complexity. At the other end of the spectrum is the generalized area law, where the interaction graph of the local Hamiltonian can be arbitrary - the generalized area law asserts that the entanglement entropy for a subset of vertices scales as its edge cut-set (the area) rather than the cardinality of the subset (volume). I will outline a recently discovered counter-example to the generalized area law. The construction is based on quantum expanders, and has a beautiful alternate description in terms of a very efficient communication complexity protocol. It is insightful to view the construction in the context of the proof of the area law in one dimension, which I will briefly sketch, leading to a discussion of prospects for two dimensional systems. I will aim to make the talk accessible to a computer science audience. Based on joint work with Itai Arad, Alexei Kitaev and Zeph Landau, and with Dorit Aharonov, Aram Harrow, Zeph Landau, Daniel Nagaj and Mario Szegedy. _______________________________________________ Toc-faculty mailing listToc-faculty@lists.csail.mit.eduhttps://lists.csail.mit.edu/mailman/listinfo/toc-faculty _______________________________________________ Theory-reading-group mailing list -http://theory.csail.mit.edu/reading-group Theory-reading-group(a)lists.csail.mit.edu <http://theory.csail.mit.edu/reading-groupTheory-reading-group@lists.csail.m…> Manage subscriptions at https://lists.csail.mit.edu/mailman/listinfo/theory-reading-group _______________________________________________ qip mailing list qip(a)mit.edu http://mailman.mit.edu/mailman/listinfo/qip

9 years, 9 months

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aspuru-list July 2014