Untempered Schism

The Untempered Schism was a sacred space-time rift located on Gallifrey.

Nature
Described by the Tenth Doctor as a "gap in the fabric of reality" from which one could "see the whole of the Vortex", (TV: The Sound of Drums) the Schism was located at the heart of the caldera, a cauldron-shaped hollow on the mountainside (PROSE: Tempered) of Solace and Solitude by the Capitol. (TV: The Sound of Drums) As the heart of the caldera, this point was the origin and exact centre of the meta-structure of history. (PROSE: The Book of the War)

Mounted in a metal hoop, with a plaque bearing the Seal of Rassilon set in front of it, the Untempered Schism played a vital part in the initiation of rites of young Time Lords-to-be. (COMIC: The Wishing Well Witch, TV: The Sound of Drums, etc.) While in earlier eras, children were sometimes ritually thrown into the Schism altogether, (COMIC: The Wishing Well Witch) by the time of the Doctor's early life, the novices were simply made to stare directly into the Vortex through the Schism. All children of Gallifrey were taken from their families at the age of 8 to enter the Academy, but had to undergo the rite first; although some would "run away" or "go mad" instead of being "inspired", the Doctor, who was among those who ran away, subsequently attended the Academy, suggesting this was not any kind of entrance test. (TV: The Sound of Drums)

Early Gallifreyan history
The Doctor noted on more than one occasion that it was direct exposure to the Time Vortex through the Untempered Schism that caused Gallifreyans to develop more quickly than other societies. Over "billions of years", it caused them to evolve into Time Lords. (COMIC: Old Girl, TV: A Good Man Goes to War, et al.) This was comparable to the way that having been conceived within the Time Vortex itself allowed the Silence to manipulate Melody Pond's biodata to make her into a proto-Time Lord capable of regeneration. (TV: A Good Man Goes to War) However, after he discovered information about the Timeless Child, suggested that the "noble creation myth" for regeneration that the Time Lords told themselves, according to which they had been "born to rule", had been a fabrication to cover up the sordid truth. (TV: The Timeless Children)

Experiments
When the Tenth Doctor's TARDIS brought him to ancient Gallifrey, billions of years before his time, he and Cindy Wu witnessed young Gallifreyans being forced into the schism by a group of Time Sentinels. (COMIC: Old Girl) During one initiation in the Dark Times, a group of students were thrown into the Schism. Their physical forms were splintered by unprotected travel through the Time Vortex. (COMIC: The Wishing Well Witch)

Initiation ceremony
At any rate, later in their history, the Schism was used by the Time Lords in an initiation ceremony for children entering the Time Lord Academy. At the age of eight, the children would be taken to the Schism and forced to stare into it. (TV: The Sound of Drums) When the children were taken, it was tradition to march to the Schism in complete silence. If a child were to tire out during the walk, they were considered a failure and carried back to live with the shame forever. (PROSE: Tempered) The Doctor and the Master agreed that the experience was traumatic, and both expressed a level of disgust at the idea of forcing a child into such an experience. The process was mandatory, (TV: The Sound of Drums, The End of Time) with one individual later known as "the Corsair" even having had to be taken to the Homeworld in the company of the Monk for "initiation", even though he'd grown up on the colony world of Cartago. The Monk stood over him, squeezing his shoulder, as he prepared to face the Tourbillon, and told him:

He was also made to wear "an initiate's robes", which felt uncomfortable and alien to him. (PROSE: The Bloodletters)

The Doctor said that, when subjected to the terrifying effects of the Schism even in his time, the children would react differently — "some would be inspired, some would run away, and some would go mad". He identified himself as one of the ones who ran away and never stopped running. (TV: The Sound of Drums) One Time Lord historian treated the Doctor's three possibilities as a genuine classification, and suggested that others who ran away included his granddaughter Susan, Romana I, K'anpo Rimpoche, the First Drax, Azmael, the Corsair, and Outsiders such as Nesbin, Ablif, and Presta. (PROSE: A Brief History of Time Lords)

During the Master's initiation, he saw "the raw power of time and space". (TV: The Sound of Drums) It was at this moment that the Drumming, a signal sent back through time by the Time Lords in the final hours of the Last Great Time War, (TV: The End of Time) entered the Master's mind, subsequently plaguing him throughout the rest of his lives. (TV: The Sound of Drums) He interpreted it as a sign of fate, a "call to war", which set him on his bloodthirsty path. (TV: Last of the Time Lords) During the ceremony, the Master observed that the Time Lords who had escorted him refused to stare in the Schism. (PROSE: Tempered)

According to the historian, those who were inspired were Savar, Runcible, Spandrell, Engin, Hilred, Kelner, Rodan, Maxil, Damon, Talor, Jerricho, Thalia, Hedin, Zorac, Flavia, Darkel, the Woman, the Partisan, Andro, Fabian, the General, and Androgar. Meanwhile, the Monk, the War Chief, Goth, the Rani, Morbius, Borusa, Salyavin, and the Visionary, were listed as having gone mad. (PROSE: A Brief History of Time Lords)

The Tenth Doctor described looking into the Schism as the first time any young Time Lord "saw eternity". (TV: The Sound of Drums) The book of A included the quote, "When I was young, I looked through eternity's eye, and eternity created me!" (PROSE: What Keeps Their Lines Alive)

When a temporal crisis rendered TARDIS travel all but impossible, the Twelfth Doctor, stranded on Gallifrey with Bill Potts, acquired a stash of Kyfred Gems and came up with the idea of using them to stabilise the temporal energy by throwing them into the Untempered Schism "like skipping stones". Bill accompanied the Doctor to the Schism, but had to wear a protective shield to avoid the sight of the Schism "melting her brain". (GAME: Lost in Time)

One source stated that the Untempered Schism was destroyed along with the rest of Gallifrey at the end of the Last Great Time War, (PROSE: Doctor Who: The Encyclopedia) whilst another account established that the planet had been saved and relocated to a pocket universe by all incarnations of the Doctor. (TV: The Day of the Doctor) Indeed, even after the Time War, the process of bringing young Gallifreyans from the Drylands to the Schism was still active. (PROSE: A Brief History of Time Lords)

Behind the scenes

 * The "time tunnel" effect seen in the Untempered Schism, and reflected in the eyes of the young Master, is the same technique used in the opening title sequence of the Doctor Who TV series from series 1 to the 2009 specials and during certain episodes from 2005 onwards where the TARDIS is shown in flight through the vortex. It was also used at the opening of The Sound of Drums to represent the transit through the space-time continuum with Jack Harkness's vortex manipulator.
 * The Schism as described by Russell T Davies possessed obvious similarities with the caldera, an element earlier introduced in the Faction Paradox novel The Book of the War: a gap in the fabric of reality on the Homeworld which served as the node point of the Web of Time, into which characters sometimes looked, or even walked, to scry the timelines, despite the experience driving at least one Lord President insane. The short story Tempered later made the connection explicit. However, the caldera was originally described as being buried beneath the Capitol, as opposed to remaining out in the open and its location known; this and other details suggested that it was intended to match accounts of the Eye of Harmony in The Deadly Assassin and later sources, though not necessarily the popular conflation of the Eye with Omega's Star.

Неистовый Разлом