We present an information-theoretic analysis of Darwin’s theory of evolution, modeled as a hill-climbing algorithm on a fitness landscape. Our space of possible organisms consists of computer programs, which are subjected to random mutations. We study the random walk of increasing fitness made by a single mutating organism. In two different models we are able to show that evolution will occur a...

W. Gao, H. Zhu, K. Giovanello, K. Smith, D. Shen, J. Gilmore, and W. Lin Department of Biomedical Engineering, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, United States, Department of Biostatistics and BRIC, University of North Carolina-Chapel Hill, Department of Psychology and BRIC, University of North Carolina-Chapel Hill, Department of Radiology, University of Nort...

W. Gao, H. Zhu, K. Giovanello, K. Smith, D. Shen, J. Gilmore, and W. Lin Department of Biomedical Engineering, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, United States, Department of Biostatistics and BRIC, University of North Carolina-Chapel Hill, Department of Psychology and BRIC, University of North Carolina-Chapel Hill, Department of Radiology, University of Nort...

We show that there exists an infinite tower of fermionic symmetries in pure d=4, N=1 supergravity on an asymptotically flat background. The Ward identities associated with these symmetries are equivalent to the soft limit of the gravitino and to the statement of supersymmetry at every angle. Additionally, we show that these charges commute into charges associated with the (unextended) Bondi-Met...

Many learning tasks involve searching through a discrete space of performance elements, seeking an element whose future utility is expected to be high. As the task of nding the global optimum is often intractable, many practical learning systems use simple forms of hill-climbing to nd a locally optimal element. However, hill-climbing can be complicated by the fact that the utility value of a pe...

When Jim Lyons-Weiler and I discussed what we might do with an Open Access journal on Cancer Informatics, we both felt that it was important to avoid loosing focus on what the end-point of both the research and its dissemination is. In all its forms cancer is inevitably an unpleasant affl iction that harms every aspect of the lives of sufferers and those who love them. Jim and I want this journ...

BACKGROUND A Hill-Sachs lesion of the humeral head after a shoulder dislocation is clinically insignificant in most cases. However, a sizable defect will engage with the anterior rim of the glenoid and cause instability even after anterior glenoid reconstruction. The purpose of this study was to evaluate the outcome of arthroscopic capsulotenodesis of the posterior capsule and infraspinatus ten...