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Synopsis: Making Hard Problems for Quantum Computers

Researchers have developed a computer algorithm that doesn’t solve problems but instead creates them for the purpose of evaluating quantum computers.

The desire for quantum computers stems from their potential to solve certain hard problems faster than classical computers. But those bragging rights haven’t actually been earned yet, as no experiment has shown this presumed speedup. Researchers from the University of Southern California, Los Angeles, and the Complutense University of Madrid, Spain, have devised an algorithm that generates extra hard problems that could offer quantum computers the chance to prove their worth.

The problems that the team focused on belong to the general class of optimization problems. The main example is the Ising model, which describes the interaction of a large number of spins within a lattice. The goal is to find the ground state, which is the orientation of spins that minimizes the interaction energy. The problem is computationally hard because there are many local minima (pseudo-ground-states) that can fool a search algorithm.

The Noise at the Bottom of the Universe

Is search of the sound of silence.


To a physicist, perfect quiet is the ultimate noise. Silence your cellphone, still your thoughts, and muffle every kind of vibration, and you would still be left with quantum noise. It represents an indeterminacy deep within nature, bursts of static and inexplicable motions that cannot be gotten rid of, or made sense of. It seems devoid of meaning.

Considering how pervasive this noise is, you might presume that physicists would have a good explanation for it. But it remains one of the great unsolved problems in science. Quantum theory is silent not just on where the noise comes from, but on how exactly it enters the world. The theory’s defining equation, the Schrödinger equation, is completely deterministic. There is no noise in it at all. To explain why we observe quantum particles to be noisy, we need some additional principle.

For physicists in the Niels Bohr tradition, the act of observation itself is decisive. The Schrödinger equation defines a menu of possibilities for what a particle could do, but only when measured does the particle actually do anything, choosing at random from the menu. Identical particles will make different choices, causing the outcomes of fundamental processes to vary in an uncontrollable way. On Bohr’s view, quantum noise cannot be explained further. It is what physicist John Wheeler called “an elementary act of creation,” with no antecedents. Genesis was not a singular event in the distant past, but an ongoing process that we bring about. We create the world by observing it.

Stanford University Researchers Help DARPA Create Mathematical Framework for Network Pattern Discovery

The Defense Advanced Research Projects Agency has demonstrated a new mathematical framework that works to help researchers discover patterns in complex scientific and engineering systems. DARPA said Thursday researchers at Stanford University created algorithms designed to explore patterns in data in order to gain insights into network structure and function under the Simplifying Complexity in Scientific Discovery [ ].

Mathematical framework that prioritizes key patterns in networks aims to accelerate scientific discovery

Nice.


Networks are mathematical representations to explore and understand diverse, complex systems—everything from military logistics and global finance to air traffic, social media, and the biological processes within our bodies. In each of those systems, a hierarchy of recurring, meaningful internal patterns—such as molecules and proteins interacting inside cells, and capacitors and resistors operating within integrated circuits—determines the functions or behaviors of those systems. The larger and more intricate a system is, however, the harder it is for current network modeling techniques to uncover these patterns and represent them in organized, easy-to-understand ways.

Researchers at Stanford University, funded by DARPA’s Simplifying Complexity in Scientific Discovery (SIMPLEX) program, have made progress in overcoming these challenges through a framework they have developed for identifying and clustering what mathematicians call “motifs”: essential but often obscure patterns within systems that are the building blocks of mathematical modeling and that facilitate the computational representation of complex systems.

A research paper describing the team’s achievement was published in Science (“Higher-order organization of complex networks”). At the heart of the team’s success was the creation of algorithms that can automatically explore and prioritize the hidden patterns in data that are fundamental to explaining network structure and function.

a mathematical framework that automatically identifies and prioritizes the patterns that are fundamental to explaining network structure and function

Doctors find link between statins and cancer survival rate

Being treated for high cholesterol with statins is being linked with a reduced risk of death and better survival from four common cancers, a medical conference has heard.

Among the patients in the study, almost 8,000 had lung cancer, 5,500 had breast cancer, 4,600 had prostate cancer and 4,500 had colon cancer, the researchers found. So the researchers think the statin treatment might explain the protective effect, rather than high cholesterol itself.

Data for patients admitted to United Kingdom hospitals between January 1, 2000-March 31, 2013 with the listed cancers were obtained from the Algorithm for Comorbidities, Associations, Length of stay and Mortality (ACALM) clinical database, which also provided data on comorbidities such as high cholesterol; mortality data was obtained from the Office of National Statistics.

Versatile microwave-driven trapped ion spin system for quantum information processing

More steps forward for QC through the discovery of a versatile effective spin system suitable for quantum simulations and universal quantum computation.


Using trapped atomic ions, we demonstrate a tailored and versatile effective spin system suitable for quantum simulations and universal quantum computation. By simply applying microwave pulses, selected spins can be decoupled from the remaining system and, thus, can serve as a quantum memory, while simultaneously, other coupled spins perform conditional quantum dynamics. Also, microwave pulses can change the sign of spin-spin couplings, as well as their effective strength, even during the course of a quantum algorithm. Taking advantage of the simultaneous long-range coupling between three spins, a coherent quantum Fourier transform—an essential building block for many quantum algorithms—is efficiently realized. This approach, which is based on microwave-driven trapped ions and is complementary to laser-based methods, opens a new route to overcoming technical and physical challenges in the quest for a quantum simulator and a quantum computer.

Air Force Seeks Ideas for How Quantum Computing Can Help Warfighters

Listen up all my QC buddies; the air force wants to hear from you. You have QC ideas for fighter jets they want you.

Guess I need to submit them some of mine.


The Air Force wants white papers that describe new ways quantum computing could help achieve its mission, according to an amended Broad Agency Announcement posted Friday. Eventually, the government could provide a test-bed where a contractor might install, develop and test a quantum computing system, according to the announcement.

Last year, the Air Force announced it had about $40 million available to fund research into, and the eventual maintenance and installation of a quantum system — a branch of emerging computing technology that relies on the mechanics of atomic particles to process complex equations.

The Air Force Research Laboratory’s Information Directorate, which focuses on processes such as signal processing, networking technology, cyber research and supercomputing, is collecting those white papers.

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