Tag: physics

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Prediction of Emerging Technologies Based on Analysis of the U.S. Patent Citation Network [ via Peter Erdi and UMich EECS ]

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Dr. Peter Erdi is one of the leading scholars studying the path of innovation as revealed through the U.S. Patent Citation network.  Above is his most recent talk – Prediction of Emerging Technologies Based on Analysis of the U.S. Patent Citation Network

For some of his additional work please see:
Patent Citation Networks Revisited: Signs of a Twenty-First Century Change?, North Carolina Law Review (2009).
Modeling Innovation by a Kinetic Description of the Patent Citation System, Physica A (2007)
Law and the Science of Networks: An Overview and an Application to the ‘Patent Explosion’, Berkeley Technology Law Journal (2007).

[Note: Load Time for the Video above is a bit slow]

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Physicist Cuts Plane Boarding Time in Half [via CNet & Hacker News]

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“… Steffen considered various methods, such as boarding people in blocks, at random, and in window seats first. He set up a model using an algorithm based on the Monte Carlo optimization method used in statistics and mathematics. He found that the most efficient boarding method is to board alternate rows at a time, beginning with the window seats on one side, then the other, minimizing aisle interference. The window seats are followed by alternate rows of middle seats, then aisle seats. He also found that boarding at random is faster that boarding by blocks.” Coverage over at C-Net

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Information Efficiency and Financial Stability

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From the abstract: “The authors study a simple model of an asset market with informed and non-informed agents. In the absence of non-informed agents, the market becomes information efficient when the number of traders with different private information is large enough. Upon introducing non-informed agents, the authors find that the latter contribute significantly to the trading activity if and only if the market is (nearly) information efficient. This suggests that information efficiency might be a necessary condition for bubble phenomena—induced by the behavior of non-informed traders—or conversely that throwing some sands in the gears of financial markets may curb the occurrence of bubbles.”  [ HT: Paul Kedrosky ]

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Controllability of Complex Networks [via Nature]

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Abstract: “The ultimate proof of our understanding of natural or technological systems is reflected in our ability to control them. Although control theory offers mathematical tools for steering engineered and natural systems towards a desired state, a framework to control complex self-organized systems is lacking. Here we develop analytical tools to study the controllability of an arbitrary complex directed network, identifying the set of driver nodes with time-dependent control that can guide the system’s entire dynamics. We apply these tools to several real networks, finding that the number of driver nodes is determined mainly by the network’s degree distribution. We show that sparse inhomogeneous networks, which emerge in many real complex systems, are the most difficult to control, but that dense and homogeneous networks can be controlled using a few driver nodes. Counterintuitively, we find that in both model and real systems the driver nodes tend to avoid the high-degree nodes.”

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“Peak Data” or “The Capacity Crunch” [From Science]

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From this week’s issue of Science comes Filling the Light Pipe by David J. Richardson. This is an important article highlighting a serious challenge facing the both the scientific and policy community.

From the abstract: “It has been a landmark year for the field of optical telecommunications, with the award of the 2009 Nobel Prize to Charles Kao for his insight in the mid-1960s that the future of communications lay in single-mode silica-based optical fibers (1) as well as the 50th anniversary of the first demonstration of the laser—both key technologies responsible for the development of the global-scale communications networks of today (2). Recently, however, a growing realization has emerged within the telecommunications industry that the end of the phenomenal growth in optical fiber communication capacity is within sight. At this year’s Optical Fiber Communication Conference (OFC 2010), several groups reported results within a factor of ~2 of the ultimate capacity limits of existing optical fiber technology. Without radical innovation in our physical network infrastructure—that is, improvements in the key physical properties of transmission fibers and the optical amplifiers that we rely on to transmit data over long distances—we face what has been widely referred to as a “capacity crunch” that could severely constrain future Internet growth, as well as having social and political ramifications.”

[HT to Paul Kedrosky]

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“A Taxonomy of Networks” New Paper on the Physics arXiv

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An exciting new paper entitled “A Taxonomy of Networks” by Jukka-Pekka Onnela, Daniel J. Fenn, Stephen Reid, Mason A. Porter, Peter J. Mucha, Mark D. Fricker & Nick S. Jones just hit the Physics arXiv.  I wanted to flag it for anyone who might be interested.

Here is the abstract: “The study of networks has grown into a substantial interdisciplinary endeavor across the natural, social, and information sciences. Yet there have been very few attempts to investigate the interrelatedness of the different classes of networks studied by different disciplines. Here, we introduced a framework to establish a taxonomy of networks from various origins. The provision of this family tree not only helps understand the kinship of networks, but also facilitates the transfer of empirical analysis, theoretical modeling, and conceptual developments across disciplinary boundaries. The framework is based on probing the mesoscopic properties of networks, an important source of heterogeneity for their structure and function. Using our method, we computed a taxonomy for 752 individual networks and a separate taxonomy for 12 network classes. We also computed three within-class taxonomies for political, fungal, and financial networks, and found them to be insightful in each case.”