![]() But this doesn't mean that string theory is "replacing point particles by strings". It is from this picture that one derives the intuition that it is the "extended nature" of the string that resolves the infinities of QFT - these 2D diagrams are smooth and do not lead to the same kind of infinities that we would need to renormalize as the ordinary Feynman diagrams, which are often thought of as the world lines of a point particle. However, there is additional data on this worldsheet that carries the information about the actual state we are scattering (a vertex operator), the string itself does not represent the scattered state while the particles in QFT certainly are the scattered states. Here, one might start to think that the string becomes analogous to the particle because the diagrams simply are two-dimensional manifolds that look like "fattened Feynman diagrams", with string interaction corresponding to higher-genus 2D manifolds. However, string theory is not a quantum field theory, and this shows in the "stringy Feynman diagrams" it uses to compute perturbative string amplitudes. The strings of string theory therefore are much more analogous to the fields of quantum field theory than to particles in this technical sense. ![]() Quantizing the movement of string in the target space then gives us quanta, which we interpret as excitations of the string and which we believe to correspond to the usual QFT particles in a low-energy effective regime. In string theory, the classical model from which we start is the one of string moving freely in some high-dimensional target space. The classical field theory corresponding to a QFT doesn't know anything about particles. In quantum field theory, particles only appear in the theory once it is quantized. They are not excitations of something, they are the fundamental objects from which standard string theory starts building its model. Keb' Mo' - Guitar, Arranger, Composer, Vocalsī.B.Strings are not quanta. Guthrie Govan - Guitar, Arranger, Composer Larry Goldings - Organ, Clavinet, Fender Rhodes Also featured on vocals are BB King, Robert Cray, Vince Gill, Keb’ Mo’, Taj Majal, Joe Bonamassa and Jonny Lang. ![]() Blending rock, blues, jazz, acoustic, country and classical, they come together for a seamless project that promises to take the listener on a musical journey and exploration of the guitar. Joining him in this tribute to the guitar, the all-star line-up includes: George Benson, BB King, Slash, Steve Lukather, John Scofield, Robert Cray and Vince Gill among many other superstars. Set for release on Concord Records /Monster Music on June 29, 2010, for 6 String Theory, Ritenour is also among the twenty legendary world class guitarists starring on the recording, which he produced along with John Burk of the Concord Music Group. On his latest endeavor, 6 String Theory, Ritenour celebrates the instrument that has allowed him this blessing, the guitar -by producing and assembling a star-studded tribute with the greatest and soon- to- be greatest guitarists of our time. As a young guitarist his diverse musical style became the foundation of over 3,000 sessions, covering a broad spectrum of artists ranging from his first session at 16 with the Mamas and Papas, to Pink Floyd, Steely Dan, Dizzy Gillespie, Sonny Rollins, Simon & Garfunkel and Frank Sinatra. During his career, he has recorded over 40 albums, with 35 chart songs and was a founding member of the group Fourplay, considered the most successful group in contemporary jazz. A career that has earned him 19 GRAMMY® nominations, a GRAMMY Award, numerous #1 spots on guitar polls, a Lifetime Achievement Award from the Canadian SJ Awards, and the prestigious “Alumnus of the Year” award from USC. ![]() 2010 marks 50 years since Lee Ritenour starting playing the guitar, setting in motion a career that legends are made of. ![]()
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