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List Of Laws
This is a list of "laws" applied to various disciplines. These are often adages or predictions with the appellation 'Law', although they do not apply in the legal sense, cannot be scientifically tested, or are intended only as rough descriptions (rather than applying in each case). These 'laws' are sometimes called rules of thumb. See List of legal topics for 'laws' in the legal sense. See List of scientific laws for falsifiable laws that are said to apply universally and literally. General * Benford's law * Hilt's law * Stigler's law of eponymy * Goodhart's law Astronomy and cosmology * Hubble's law * Titius–Bode law * Dermott's law Technology * Amdahl's law (maximum possible speed-up to a parallel program when adding more computing power) * Bell's law of computer classes (corollary to Moore's law for computer class formation) * Brooks's law * Conway's law * Dennard scaling * Engelbart's law * Eroom's law * Godwin's law (Prediction of internet debating patterns) * Grosch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adage
An adage (; Latin: adagium) is a memorable and usually philosophical aphorism that communicates an important truth derived from experience, custom, or both, and that many people consider true and credible because of its longeval tradition, i.e. being handed down generation to generation, or memetic replication. Variations and nature An adage may warn against a failure to plan, be interesting observations, ethical rules, or skeptical comments on life in general, such as "do not count your chickens before they hatch", "do not burn your bridges", and . Some adages are products of folk wisdom that attempt to summarize a basic truth; these are generally known as " proverbs" or "bywords". An adage that describes a general moral rule is a " maxim". A pithy expression that has not necessarily gained credibility by tradition, but is distinguished by especial depth or excellent style is denominated an " aphorism", while one distinguished by wit or irony is often denominated an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conway's Law
Conway's law is an adage that states organizations design systems that mirror their own communication structure. It is named after the computer programmer Melvin Conway, who introduced the idea in 1967. His original wording was: The law is based on the reasoning that in order for a product to function, the authors and designers of its component parts must communicate with each other in order to ensure compatibility between the components. Therefore, the technical structure of a system will reflect the social boundaries of the organizations that produced it, across which communication is more difficult. In colloquial terms, it means complex products end up "shaped like" the organizational structure they are designed in or designed for. The law is applied primarily in the field of software architecture, though Conway directed it more broadly and its assumptions and conclusions apply to most technical fields. Variations Eric S. Raymond, an open-source advocate, restated Conway's la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metcalfe's Law
Metcalfe's law states that the value of a telecommunications network is proportional to the square of the number of connected users of the system (''n''2). First formulated in this form by George Gilder in 1993, and attributed to Robert Metcalfe in regard to Ethernet, Metcalfe's law was originally presented, c. 1980, not in terms of users, but rather of "compatible communicating devices" (e.g., fax machines, telephones). Only later with the globalization of the Internet did this law carry over to users and networks as its original intent was to describe Ethernet connections. Network effects Metcalfe's law characterizes many of the network effects of communication technologies and networks such as the Internet, social networking and the World Wide Web. Former Chairman of the U.S. Federal Communications Commission Reed Hundt said that this law gives the most understanding to the workings of the Internet. Metcalfe's Law is related to the fact that the number of unique possibl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linus's Law
In software development, Linus's law is the assertion that "given enough eyeballs, all bugs are shallow". The law was formulated by Eric S. Raymond in his essay and book '' The Cathedral and the Bazaar'' (1999), and was named in honor of Linus Torvalds. A more formal statement is: "Given a large enough beta-tester and co- developer base, almost every problem will be characterized quickly and the fix obvious to someone." Presenting the code to multiple developers with the purpose of reaching consensus about its acceptance is a simple form of software reviewing. Researchers and practitioners have repeatedly shown the effectiveness of reviewing processes in finding bugs and security issues. Validity In ''Facts and Fallacies about Software Engineering,'' Robert Glass refers to the law as a "mantra" of the open source movement, but calls it a fallacy due to the lack of supporting evidence and because research has indicated that the rate at which additional bugs are uncovered do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landauer's Principle
Landauer's principle is a physical principle pertaining to the lower theoretical limit of energy consumption of computation. It holds that "any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information-bearing degrees of freedom of the information-processing apparatus or its environment".. Another way of phrasing Landauer's principle is that if an observer loses information about a physical system, heat is generated and the observer loses the ability to extract useful work from that system. A so-called logically reversible computation, in which no information is erased, may in principle be carried out without releasing any heat. This has led to considerable interest in the study of reversible computing. Indeed, without reversible computing, increases in the number of computations per joule of energy dissipated must eventually come to a halt. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koomey's Law
Koomey's law describes a trend in the history of computing hardware: for about a half-century, the number of computations per joule of energy dissipated doubled about every 1.57 years. Professor Jonathan Koomey described the trend in a 2010 paper in which he wrote that "at a fixed computing load, the amount of battery you need will fall by a factor of two every year and a half.". This trend had been remarkably stable since the 1950s ( ''R''2 of over 98%). But in 2011, Koomey re-examined this data and found that after 2000, the doubling slowed to about once every 2.6 years. This is related to the slowing of Moore's law, the ability to build smaller transistors; and the end around 2005 of Dennard scaling, the ability to build smaller transistors with constant power density. "The difference between these two growth rates is substantial. A doubling every year and a half results in a 100-fold increase in efficiency every decade. A doubling every two and a half years yields just a 16 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kryder's Law
Mark Howard Kryder (born October 7, 1943 in Portland, Oregon) was Seagate Corp.'s senior vice president of research and chief technology officer. Kryder holds a Bachelor of Science degree in electrical engineering from Stanford University and a Ph.D. in electrical engineering and physics from the California Institute of Technology. Kryder was elected a member of the National Academy of Engineering in 1994 for contributions to the understanding of magnetic domain behavior and for leadership in information storage research. He is known for "Kryder's law", an observation from the mid-2000s about the increasing capacity of magnetic hard drives. Kryder's law projection A 2005 ''Scientific American'' article, titled "Kryder's Law", described Kryder's observation that magnetic disk areal storage density was then increasing at a rate exceeding Moore's Law. The pace was then much faster than the two-year doubling time of semiconductor chip density posited by Moore's law. In 2005, comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haitz's Law
Haitz's law is an observation and forecast about the steady improvement, over many years, of light-emitting diodes (LEDs). It claims that every decade, the cost per lumen (unit of useful light emitted) falls by a factor of 10, and the amount of light generated per LED package increases by a factor of 20, for a given wavelength (color) of light. It is considered the LED counterpart to Moore's law, which states that the number of transistors in a given integrated circuit doubles every 18 to 24 months. Both laws rely on the process optimization of the production of semiconductor devices. Haitz's law is named after Roland Haitz (1935–2015), a scientist at Agilent Technologies among others. It was first presented to the larger public at Strategies in Light 2000, the first of a series of annual conferences organized by Strategies Unlimited. Besides the forecast of exponential development of cost per lumen and amount of light per package, the publication also forecast that the luminous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gustafson's Law
In computer architecture, Gustafson's law (or Gustafson–Barsis's law) gives the speedup in the execution time of a task that theoretically gains from parallel computing, using a hypothetical run of ''the task'' on a single-core machine as the baseline. To put it another way, it is the theoretical "slowdown" of an ''already parallelized'' task if running on a serial machine. It is named after computer scientist John L. Gustafson and his colleague Edwin H. Barsis, and was presented in the article ''Reevaluating Amdahl's Law'' in 1988. Definition Gustafson estimated the speedup S of a program gained by using parallel computing as follows: : \begin S &= s + p \times N \\ &= s + (1 - s) \times N \\ &= N + (1 - N) \times s \end where * S is the theoretical speedup of the program with parallelism (scaled speedup); *N is the number of processors; * s and p are the fractions of time spent executing the serial parts and the parallel parts of the program on the ''parallel' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grosch's Law
Grosch's law is the following observation of computer performance, made by Herb Grosch in 1953: I believe that there is a fundamental rule, which I modestly call ''Grosch's law'', giving added economy only as the square root of the increase in speed — that is, to do a calculation ten times as cheaply you must do it hundred times as fast. This adage is more commonly stated as Computer performance increases as the square of the cost. If computer A costs twice as much as computer B, you should expect computer A to be four times as fast as computer B. Two years before Grosch's statement, Seymour Cray was quoted in ''Business Week'' (August 1963) expressing this very same thought: Computers should obey a square law — when the price doubles, you should get at least four times as much speed. The law can also be interpreted as meaning that computers present economies of scale: the more costly is the computer, the price–performance ratio linearly becomes better. This implies tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Godwin's Law
Godwin's law, short for Godwin's law (or rule) of Nazi analogies, is an Internet adage asserting that as an online discussion grows longer (regardless of topic or scope), the probability of a comparison to Nazis or Adolf Hitler approaches 1. Promulgated by the American attorney and author Mike Godwin in 1990, Godwin's law originally referred specifically to Usenet newsgroup discussions. He stated that he introduced Godwin's law in 1990 as an experiment in memetics. Later it was applied to any threaded online discussion, such as Internet forums, chat rooms, and comment threads, as well as to speeches, articles, and other rhetoric where ''reductio ad Hitlerum'' occurs. In 2012, "Godwin's law" became an entry in the third edition of the ''Oxford English Dictionary''. In 2021, Harvard researchers published an article showing the phenomenon does not occur with statistically meaningful frequency in Reddit discussions. Generalization, corollaries, and usage There are many corollaries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
