Definitions of quantum computers
Since the world is quantum, any computer is a quantum computer. Conventional computers are just weak quantum computers, since they don’t exploit intrinsically quantum effects, such as superposition and entanglement.
A quantum computer is a computer that uses intrinsically quantum effects that cannot naturally be modeled by classical physics. Classical computers may be able to mathematically simulate instances of such computers, but they are not implementing the same kinds of quantum operations.
Definition 2, where there are strong tests or proofs of the quantum effects at play (e.g. by doing Bell tests).
A quantum computer is a computer that uses intrinsically quantum effects to gain some advantage over the best known classical algorithms for some problem.
A quantum computer is a computer that uses intrinsically quantum effects to gain an asymptotic speed-up over the best known classical algorithms for some problem. (The difference with definition 3 is that the advantage is a fundamental algorithmic one that grows for larger instances of the problem; versus advantages more closely tied to hardware or restricted to instances of some bounded size.)
A quantum computer is a computer that is able to capture the full computational power of quantum mechanics, just as conventional computers are believed to capture the full computational power of classical physics. This means, e.g. that it could implement any quantum algorithm specified in any of the standard quantum computation models. It also means that the device is in principle scalable to large sizes so that larger instances of computational problems may be tackled.
by Michele Mosca
Grant Morrison about Multiversity
'The Multiversity' has been a labor of love almost eight years in the making, and brings together an unstoppable supergroup of artists — Reis, Sprouse, Oliver, Quitely, Stewart and more — with a cast of unforgettable characters from the 52 alternative Earths of the known DC Multiverse!
Prepare to meet the Vampire Justice League of Earth-43, the Justice Riders of Earth-18, Superdemon, Doc Fate, the super-sons of Superman and Batman, the rampaging Retaliators of Earth-8, the Atomic Knights of Justice, Dino-Cop, Sister Miracle, Lady Quark, the legion of Sivanas, the Nazi New Reichsmen of Earth-10 and the LATEST, greatest superhero of Earth-Prime — YOU!
Comprising seven complete adventures — each set in a different parallel universe — a two part framing story, and comprehensive guidebook to the many worlds of the Multiverse, ‘The Multiversity’ is more than just a multi-part comic book series, it’s a cosmos-spanning, soul-shaking experience that puts YOU on the front line in the Battle For All Creation against the demonic destroyers known as the Gentry!
But beware! Power has a cost, and at the heart of this epic tale waits the cursed and malignant comic book called ‘Ultra Comics’…
How safe is YOUR head?
Join us, if you dare, for ‘The Multiversity!
Image credit: Ivan Reis, Joe Prado
Mickey Mouse: The World to Come, unused cover by Jonathan Gray
Generator Venice, Venice
Venice is known for its pricey accommodation and even the budget options are relatively expensive. Fortunately, Generator Venice in Venice, Italy helps cushion the budget blow with several dorms, trendy decor, a cafe and reception area open 24 hours, and what is probably the best hostel bed I’ve ever slept in. The whole place has a fresh, clean feeling to it and looks like it was decorated by Urban Outfitters.
Alana of Paperplanesblog via eTramping
A new way to see the stars
Space Ghost #2, February 2005, cover by Alex Ross
Portrait of a small boy reading by Gluyas Williams