Half-life

Half-life (t_1⁄2) is the amount of time required for the amount of something to fall to half its initial value. The term is very commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay, but it is also used more generally for discussing any type of exponential decay.

The original term, dating to Ernest Rutherford's discovery of the principle in 1907, was "half-life period", which was shortened to "half-life" in the early 1950s. Rutherford applied the principle of a radioactive element's half-life to studies of age determination of rocks by measuring the decay period of radium to lead-206.

Half-life is used to describe a quantity undergoing exponential decay, and is constant over the lifetime of the decaying quantity. It is a characteristic unit for the exponential decay equation. The term "half-life" may generically be used to refer to any period of time in which a quantity falls by half, even if the decay is not exponential. The table on the right shows the reduction of a quantity in the number of half-lives elapsed. For a general introduction and description of exponential decay, see exponential decay. For a general introduction and description of non-exponential decay, see rate law. The converse of half-life is doubling time.

Half-Life 2

Half-Life 2 (stylized as HλLF-LIFE²) is a first-person shooter video game and the sequel to Half-Life (1998). Developed by Valve Corporation, it was released on November 16, 2004, following a five-year $40 million development, during which a substantial part of the project was leaked and distributed on the Internet. The game was developed alongside Valve's Steam software. It introduced the Source game engine and, because of Steam, was the first single-player video game to require online product activation.

Some years after the events of Half-Life, protagonist Gordon Freeman is woken by the enigmatic G-Man to find the world has been taken over by the alien Combine. Joined by allies including resistance fighter Alyx Vance, Gordon searches for a way to free humanity using a variety of weapons, including the object-manipulating gravity gun.

Like its predecessor, Half-Life 2 received critical acclaim. It was praised for its advanced physics, animation, sound, AI, graphics, and narrative. The game won 39 "Game of the Year" awards and the title of "Game Of The Decade" at the 2012 Spike Video Game Awards. Over 6.5 million copies of Half-Life 2 were sold at retail by December 3, 2008, (not including Steam sales); as of February 9, 2011, Half-Life 2 had sold over 12 million copies. Half-Life 2 is considered one of the greatest video games of all time.

Duncan Sheik

Duncan Sheik (born November 18, 1969) is an American singer-songwriter and composer. Initially finding success as a singer, most notably for his 1996 debut single "Barely Breathing", he later expanded to compositions for motion pictures and the Broadway stage, such as the successful musical, Spring Awakening, where he won multiple Tonys and a Grammy. Sheik practices Nichiren Buddhism and is a member of the US branch of the worldwide Buddhist association Soka Gakkai International.

Early career

After being raised by both his parents in Montclair, New Jersey and his grandparents in Hilton Head, South Carolina (of whom his Juilliard-trained grandmother taught him piano), and after graduating from Phillips Academy, Andover in 1988, Sheik studied semiotics at Brown University, and moved to Los Angeles. Playing for other artists, including Liz and Lisa (with Lisa Loeb and Elizabeth Mitchell), Sheik also played on His Boy Elroy's 1993 album through his connections from fellow Brown alum, Tracee Ellis Ross. He is the half brother of Broadway actress Kacie Sheik.

My World

My World may refer to:

Books

Music

Albums

Songs

My World (Bryn Christopher album)

My World is the debut studio album released by Bryn Christopher. It was released in the United Kingdom on 8 September 2008. The first single, "The Quest" was released on 8 June 2008 and peaked at #45 in the UK Singles Chart. The second single was released in September 2008, called "Smilin'" it peaked at #31. The third single, "Fearless" was released on 18 January 2009, but failed to chart, as did the final single "Taken Me Over".

The album peaked at #18 on the UK Albums Chart. After the commercial failure of both album and singles, Christopher parted ways with Polydor.

Track listing

Bonus tracks

My World (EP)

My World is the debut extended play (EP) by Canadian recording artist Justin Bieber. It was released on 17 November 2009, by Island Records. The album is considered the first half of a two-piece project, later being supplemented by his debut studio album My World 2.0 (2010). After signing a recording contract in light of his growing popularity on YouTube, Bieber worked with collaborators including his mentor Usher, in addition to producers Tricky Stewart, The-Dream, and Midi Mafia. Its music incorporates pop and R&B styles, and lyrically discusses teen romance and coming of age situations.

Upon its release, My World received generally favorable reviews from music critics, who complimented its production. It debuted at number six on the US Billboard 200 with first-week sales of 137,000 copies. In doing so, it became the strongest-debuting release for a new artist in 2009, though it was topped the following week by I Dreamed a Dream by Susan Boyle, which moved 701,000 units. Upon the release of My World 2.0 in March 2010, its predecessor peaked at number five. Less than two months after its release, the record was certified platinum by the Recording Industry Association of America (RIAA) for sales exceeding one million copies. Internationally, the extended play attained similar success. It debuted atop the Canadian Albums Chart, where it was later certified double platinum. It additionally attained double platinum recognition in the United Kingdom.