The Matrix


 * For the novel, see Matrix (novel).

The Matrix or the Matrix was a domain within the APC Net (for Amplified Panatropic Computer Network). The terms APC Net and Matrix are often used interchangeably. The APC Net served as a supercomputer used by the Time Lords. The Time Lords, specifically the High Council, used the Matrix both as a storehouse of knowledge and to predict future events.

Characteristics
The Matrix, specifically, contained a simulated reality environment, once described as a "micro-universe" (DW: The Ultimate Foe) which served as storage for the personalites of Time Lords now without physical bodies. Living beings could also access the Matrix. The terms Matrix and APC Net, however, have sometimes gotten used interchangeably.

Physically, the Matrix stored the memories of dead Time Lords, storing them in a framework electrochemical cells. (DW: The Deadly Assasin) It also receives input from sensors contained within TARDISes. (source?) The Matrix is not only a record of the past but can actually predict the future as well. The amount of knowledge in the Matrix, though vast, is not complete, and can be tampered with if given the right amount of access. The unauthorised extraction of a Time Lord's bio-data from the Matrix is an offence tantamount to treason (DW: Arc of Infinity). In fact, a particularly skilled person such as the Valeyard, could create images of false events that never had and never would happen. (DW: Mindwarp, Terror of the Vervoids, The Ultimate Foe)

The environment of the Matrix
To living beings, the Matrix could appear relatively like conventional reality (DW: The Deadly Assassin, The Ultimate Foe) or like a dream-like place of surreality (DWM: The Tides of Time) or a simple dark void (DW: Arc of Infinity) or often first in one state, giving way to another. Basic physical laws remain malleable, able to bend or break, according to the will of the inhabitant. The more experience with the Matrix and the greater the will of the occupant, the greater the control over the local "reality".

Beings known as the Matrix Lords, including Rassilon himself "lived" here and could direct actions from within it. They created, for example, a physical agent, Shayde, to act for them in the outside world. (DWM: The Tides of Time)

Physical access
Access to the Matrix is obtained through an apparatus connected to or enclosing the head of the user. (DW: The Deadly Assasin) The Crown of Rassillon worn by the Lord or Lady President provides to them instant access. (DW: The Invasion of Time) The Keeper of the Matrix, who held the Key of Rassilon that granted access to the Seventh Door, which was thought legendary until the Doctor used the Key to access to it. The Seventh Door allowed physical access to the Matrix by living persons. (DW: The Ultimate Foe)

Conflicting accounts of the fate of the Matrix
An ancient Gallifreyan evil named Pandora also survives and emerges from a special partition within the Matrix. Lady President Romana was eventually able to destroy the entity by destroying the Matrix itself. (BFG)

Another account says that Gallifrey was destroyed by the Eighth Doctor to prevent the voodoo cult Faction Paradox from starting a time war between the Time Lords and an unspecified Enemy. (EDA: The Ancestor Cell) It was later revealed that the Time Lords had survived within the Matrix, which had then been downloaded into the Doctor's mind, although he had to sacrifice much of his memory to make space for it. Their reconstruction was possible, but would require a sufficiently advanced computer. The question of whether or not the Time Lords would be restored remains unanswered. (EDA: The Gallifrey Chronicles)


 * This event may take place in an alternative timeline or in the future, relative to the other event, given that by this time, Romana had regenerated into a third incarnation.


 * Possibly both they and the planet are restored at some point before Gallifrey's later destruction.