Alistair Cockburn

Alistair Cockburn (born November 19, 1953) is an American computer scientist, primarily for the implementation of agile methodology and use cases in software development. See the page for more information.
==Googological contribution==
Though he is primarily involved in software development, he has coined and explained the fuga- family of prefixes in response to his then-six-year-old son, Kieran Cockburn's response of "gargoogolplex". These prefixes are devised to discuss how kids might create prefixes to indicate (repeated) application of conventional fast-growing arithmetic operations on a given number. This blog can be seen (now deadlinked, but archival links exist) on his blog A Fuga Really Big Numbers.A Fuga Really Big Numbers
The prefixes he devised, in order of growth rate, are:
*gar-: The square of a number, \(n^2\), a backformation of gargoogolplex which turns out to be the square of gargoogolplex.
*fz-: The number raised to itself, \(n^n = n ↑ n\), by increasing the exponent in this polynomial expression \(n^2\).
*fuga-: The number raised to itself, repeated that number of times, \(\underbrace{n ↑ n ↑ n ↑ ... ↑ n}_n\). 
**The non-power associative nature of exponentiation leads to two possible values of fuga.
**If done left associatively, i.e. \(\underbrace{(...((n ↑ n) ↑ n) ↑ ...) ↑ n}_n\), as performed sequentially on a calculator, it reduces to a double-exponential expression \(n^{n^{n-1}}\). He agreed to refer fuga- to this value.
**If done right-associatively, i.e. \(\underbrace{n ↑ (n ↑ (... (n ↑ n))}_n\), it leads to the tetrational expression \(n↑↑n\) or pentational expression \(n↑↑↑2\). He later agreed to refer to such a function as megafuga-.3.2.2 - The Fz, The Fuga & The Megafuga
*He also mentions kids might say “Well my space commander rules fuga-fuga-fuga-fuga-fuga-fuga-fuga-fuga- ...” after learning the meaning of fuga- before they are called for dinner. It leads to pentational growth if all operations are done right-associatively.
**A fugafugagargoogolplex is \((10^{2×10^{100}} ↑↑ 10^{2×10^{100}}) ↑↑ (10^{2×10^{100}} ↑↑ 10^{2×10^{100}})\)\( = (10^{2×10^{100}}↑↑↑2) ↑↑ (10^{2×10^{100}}↑↑↑2) = (10^{2×10^{100}}↑↑↑2)↑↑↑2\) 
**Repeated applications of fuga- indicate raising the number to the second pentation repeatedly, i.e. \((...((10^{2×10^{100}}↑↑↑2)↑↑↑2)↑↑↑2)...)↑↑↑2\). He also mentioned hyperoperators.
He has also devised two more functions after discussing about the Ackermann function in a forum discussion.Really Big Numbers
*gag: The number \(A(n,n)\), the diagonalization of the binary Ackermann function.
*mag: The number \(A^n(n)\), where \(A(n)\) is the gag function and the exponent indicate function iteration.
These prefixes are not as important in googology, but are more for the purpose of discussing how kids might accidentally invent new prefixes, and then invent more after learning new meanings when trying to devise a larger number. Most terms using these prefixes are coined by Sbiis Saibian instead. However, a few numbers are primarily known using these prefixes, notably gargoogolplex over the expression "the square of googolplex", and (mega)fugagargoogolplex over "the second pentation of gargoogolplex".
== Biographyhttps://alistaircockburn.com/Bio == 
In 1993, after two years of interviewing teams around the world on "What makes a successful project?", he wrote for the IBM Consulting Group an early version of what we now call an agile methodology. He and IBM used that methodology successfully in 1994 on a 18-month, $15M, fixed-price, fixed scope Smalltalk project, with Alistair as lead consultant and technical coordinator.
In 1998 he helped the Central Bank of Norway successfully deliver a difficult mainframe project that merged all the bank-to-bank transactions in the country of Norway. He also designed the Crystal family of methodologies while at the Central Bank of Norway.
In 2001, he organized the historic meeting in Snowbird, Utah, in which he and 16 other people from around the world wrote the Agile Manifesto. That manifesto revolutionized the field of software development, and then product management and eventually project management and organizational development in general. The "agile" approach - once considered radical - is now recommended in all industries from startups to government defense contracts, and even to government departments themselves, and social impact projects.
He published books in 1997 (Surviving Object-Oriented Projects), 2000 (Writing Effective Use Cases), 2001 (Agile Software Development), 2003 (his PhD dissertation, "People and Methodologies in Software Development), 2004 (Patterns for Effective Use Cases), 2005 (Crystal Clear), 2006 (Agile Software Development: The Cooperative Game, 2nd ed.).
In 2015, Dr. Cockburn synthesized his advice to just four words: Collaborate, Deliver, Reflect, Improve - what he calls the Heart of Agile. These four words make any initiative more effective and more enjoyable to work on. Dr. Cockburn and his associates at the Heart of Agile Academy apply all the techniques they learn to different project situations.
With his background, Dr. Cockburn is one of the few people in the world who can authoritatively relate agile development to the need for executive control, balancing fiduciary responsibility with the need to stay responsive to a changing world. He stays grounded by consulting, teaching and working with project practitioners in all active roles, particularly project managers, product owners, scrum masters, coaches and programmers. This real-problem contact keeps him in tune with the changing work situations.
== Sources ==
== External links ==
*Official website
*The Fz, The Fuga & The Megafuga
*3.2.2 - The Fz, The Fuga & The Megafuga
Category:People
Category:Fuga-