Theory

In recent years, quantum computers have lost some of their luster. In the 1990s, it seemed that they might be able to solve a class of difficult but common problems — the so-called NP-complete problems — exponentially faster than classical computers. Now, it seems that they probably can't. In fact, until this week, the only common calculation where quantum computation promised exponential gains was the factoring of large numbers, which isn't that useful outside cryptography. In a paper appearing today in Physical Review Letters, however, MIT researchers present a new algorithm that could bring the same type of efficiency to systems of linear equations — whose solution is crucial to image processing, video processing, signal processing, robot control, weather modeling, genetic analysis and population analysis, to name just a few applications.Quantum computers are computers that exploit the weird properties of matter at extremely small scales. Where a bit in a classical computer can re...

Ulla Matfolk sent to me some interesting material at the web page of Dr. Mae-Wan Ho. The first article is Water electric. The second one is Making Fuel from Water. Both articles relate closely to what might be called the holy grail of artificial photosynthesis. The unreasonable effectiveness of photosynthesis in the sense that the waste of energy during the process is extremely small, makes artificial photosynthesis an excellent candidate for the final solution of energy problems as far energy sources and minimization of wastes are considered. In the following I comment only the first paper in detail from TGD viewpoint.

Excellent and well illustrated article about sound generation in general.

The next class of scan conversion algorithms that we will discuss are the area-filling algorithms. These algorithms operate on a raster while completely unaware of any other primitives previously drawn.

It is a fundamental problem exactly how the intentional and the physical conceptualization are related. If functions are seen primarily as ‘added to’ the physical substrate, or as realized in physical objects, then the question remains how these functions are related to the mental states of human individuals -which, after all, form the core of the intentional conceptualization. If functions are seen primarily as patterns of mental states, on the other hand, and exist, so to speak, in the heads of the designers and users of artifacts only, then it becomes somewhat mysterious how a function relates to the physical substrate in a particular artifact. Given this state of affairs, the general aim of the research program is to develop a coherent conceptual framework for describing technical artifacts, which takes due account of their dual nature.