Academic literature on the topic 'Abraham's formula'

The concept of self-force on a moving charge is introduced along with the idea of electromagnetic mass. Lorentz’s calculation of the self-force is presented that yields an analytical form of the self-force on an accelerating sphere of charge. The equations of motion for a charge including self-force are derived, known as the Abraham–Lorentz formula. This formula is applied to sinusoidal motion and constant acceleration and its general solution is shown to result in runaway and pre-acceleration. The Landau–Lifshitz approximation alleviates these issues and the self-force is shown to act only over an experimentally extremely short characteristic time. Additionally, issues include the problem that the dynamically calculated electromagnetic mass is 4/3 the statically calculated one; the introduction of Poincare stresses reconciles this difference. Finally, the infinite electromagnetic mass problem of a point-like particle is shown to be manageable by considering advanced as well as retarded waves in the potentials.

This chapter focuses on Dublin, Trinity College, MS 432, a miscellany often neglected in criticism, with the exception of two texts within it, a romance, King Robert of Sicily, and a play, the Northampton Abraham and Isaac. Although clearly missing parts of its original contents, the manuscript displays more coherence than previously thought, and deserves a re-examination, both of the label previously given to it (miscellany; commonplace book) and of its contents. I examine formal features, such as the presentation of all the verse narratives, in what resembles a dramatic/debate format, and the association of rhyme royal with the authority figure of a ‘Doctor’. These choices were possibly informed by its compiler’s choice to record or produce dramatic pieces performed in his region/locality, perhaps for educational purposes. The compiler might have been a schoolmaster, or someone who had an interest in presenting materials of interest to one.

This chapter discusses how Leo Wharton got into the film industry. Leo's earliest documented stage appearance was in 1893, in the play The Fairies' Well. After a few years of itinerant acting, Leo was able to secure steadier employment at the Hopkins Grand Opera in Saint Louis, where his brother Ted was already performing. As part of Colonel Hopkins's theatrical company, Leo assumed various stage roles in the popular daylong “continuous performance” programs that Hopkins pioneered, which combined live drama and between-the-acts vaudeville. Leo's first known (and first credited) film appearance was in the title role of Lincoln in Abraham Lincoln's Clemency (1910), a photoplay produced by Ted Wharton for Pathé. The role not only garnered good reviews for his sympathetic performance and even for his resemblance to the revered figure whom he was portraying; it also led to an offer as a director for Pathé, the studio for which Ted was then working. There, Leo began directing similar shorts, such as the period historical drama The Rival Brothers' Patriotism (1911). Since early movie audiences seemed especially fond of marital comedies, Leo produced several shorts in 1913 that revolved around wedding-day complications. While these and other short pictures that Leo produced for Pathé were often predictable in their plotting and formulaic in their execution, they were nonetheless popular with audiences and profitable for Pathé. Moreover, they established his reputation in the industry.

Jeopardy! is a popular game show that, in various incarnations, has been on television for more than 50 years. The show is a test of general knowledge with the twist that the clues are answers and the contestants respond with questions that fit the answers. For example, the clue, “16th President of the United States,” would be answered correctly with “Who is Abraham Lincoln?” There are three contestants, and the first person to push his or her button is given the first chance to answer the question orally (with the exception of the Final Jeopardy clue, when all three contestants are given 30 seconds to write down their answers). In many ways, the show is ideally suited for computers because computers can store and retrieve vast amounts of information without error. (At a teen Jeopardy tournament, a boy lost the championship because he wrote “Who Is Annie Frank?” instead of “Who is Anne Frank.”A computer would not make such an error.) On the other hand, the clues are not always straightforward, and sometimes obscure. One clue was “Sink it and you’ve scratched.” It is difficult for a computer that is nothing more than an encyclopedia of facts to come up with the correct answer: “What is the cue ball?” Another challenging clue was, “When translated, the full name of this major league baseball team gets you a double redundancy.” (Answer: “What is the Los Angeles Angels?”) In 2005 a team of 15 IBM engineers set out to design a computer that could compete with the best Jeopardy players. They named it Watson, after IBM’s first CEO, Thomas J. Watson, who expanded IBM from 1,300 employees and less than $5 million in revenue in 1914 to 72,500 employees and $900 million in revenue when he died in 1956. The Watson program stored the equivalent of 200 million pages of information and could process the equivalent of a million books per second. Beyond its massive memory and processing speed, Watson can understand natural spoken language and use synthesized speech to communicate. Unlike search engines that provide a list of relevant documents or web sites, Watson was programmed to find specific answers to clues. Watson used hundreds of software programs to identify the keywords and phrases in a clue, match these to keywords and phrases in its massive data base, and then formulate possible responses.

Increasingly, the notion of manager is confronted with that of leader. The literature written on this subject is considerable (John P. Kotter and Abraham Zaleznik being only two of the sound names that can be mentioned in this endeavor). Zaleznik proposed that managers were results driven and leaders were creative artists. Kotter proposed that leaders navigated change and managers navigated complexity. John P. Kotter says that today's managers need to know how to lead, be managers and leaders. The differences are: 1. Management is more formal and scientific than leadership. Management is an ex