Time field

The time field was a body of time energy that spilled from cracks in the fabric of time and space. The cracks were created by the Silence when they blew up the Doctor's TARDIS on 26 June 2010, as a means of preventing the Doctor from reaching Trenzalore and answering the Time Lords' message which was sent through the very same cracks the Silence created when they blew up the TARDIS. (TV: The Time of the Doctor)

Cracks
The cracks were described by the Eleventh Doctor as "two parts of space and time that should never have touched, pressed together". They were present in the very fabric of spacetime — a crack that appeared to be part of a wall would still be there if the wall were removed. (TV: The Eleventh Hour) They were also described as "cracks in the skin of the universe." (TV: The Pandorica Opens)

According to Rosanna Calvierri, the cracks ranged in size from tiny to "as big as the sky", and some connected to other worlds, while others led only to "silence, and the end of all things". (TV: The Vampires of Venice)

Some cracks acted like wormholes and could be opened to allow a passage between the places on either side. Rosanna Calvierri and her family travelled through a crack of this kind, (TV: The Vampires of Venice) as did Prisoner Zero. (TV: The Eleventh Hour) A sonic screwdriver could widen a crack, and if a crack was open wide enough, the forces would invert, and the crack would snap itself shut. (TV: The Eleventh Hour)

Other cracks released pure time energy able to wipe individuals from time itself and remove events from history. Time travellers such as the Doctor would still remember them, at least so long as the removed event or person did not relate to the time traveller's direct past. (TV: Flesh and Stone, Cold Blood)

Also, when the time energy erased people and events, the consequences would still remain: the Byzantium remained crashed when the Weeping Angels who had caused it were erased; Amelia Pond still existed when her parents were erased from history, as did River Song when her father met the same fate. (TV: Flesh and Stone, Cold Blood, The Big Bang) This time energy was visible as a glow of bright white light, which sometimes extended tendrils from the crack towards nearby people and objects to consume them. Although it would be common sense to run away from this, the Clerics were stupid enough to go right towards it and investigate. (TV: Cold Blood, Flesh and Stone)

The Doctor guessed that the time energy from these kind of cracks had erased events such as the CyberKing walking over London in the Victorian era, and the 2009 Dalek invasion of Earth, the latter being one of Earth's most publicly visible invasions. (TV: Flesh and Stone)



Regardless of the size and what was on the other side, all cracks appeared to be of the same shape and orientation. The Doctor stated that the only way to close such a crack was for it to consume a complicated space-time event, such as himself or a large group of Weeping Angels; all of them together were equivalent to him. River Song volunteered to let herself be consumed, but the Doctor — potentially from a position of ignorance — sneered at the idea and said that she wasn't even as complicated as one Angel. (TV: Flesh and Stone) It's possible the more complicated a space-time event is, the more immunity it has to being absorbed; the Doctor was able to reach into a crack, with his hand covered by a hanky, to pull out a piece of shrapnel from the explosion that created the cracks. Although he didn't get erased, it was painful given his yells. (TV: Cold Blood)

Origin
The cracks in time originated in the destruction of the Doctor's TARDIS when it came under the control of the Silence (TV: The Time of the Doctor) which made it materialise outside Amy Pond's house on 26 June 2010. River Song tried to prevent the explosion, but completely lost control of the TARDIS. (TV: The Pandorica Opens) It exploded, cracking points in time and space, some of which the Eleventh Doctor had been to. This resulted in the majority of the universe never existing, but the TARDIS preserved Earth by putting itself in a time loop at the moment of its death. The heat from the perpetual explosion heated the alternate Earth in place of the sun. (TV: The Big Bang)

Tasha Lem later revealed that a rogue faction of the Church of Silence was behind the attempted destruction of the TARDIS — in an effort to stop the Doctor from bringing the Time Lords and Gallifrey back (thus potentially restarting the Last Great Time War). This action resulted in a "Destiny Trap" by which the renegade Silence faction ended up creating the very cracks through which the Time Lords could return. (TV: The Time of the Doctor) In short, their efforts were pointless.

Closing
Having determined that the Pandorica — designed as the perfect prison — still contained some atoms of the original universe that existed prior to the TARDIS exploding, the Doctor flew it into the heart of the TARDIS explosion. Using the remaining atoms of the original universe inside the Pandorica and the restoration field, he repaired the damage caused by the cracks. The universe and the timeline were reset, all of the cracks began to close and the versions of Amy, Rory, and River that were relevant to the old timeline were restored to their proper places in time. To fully close the cracks, the Doctor allowed himself be absorbed by one and erased from existence.

Using the ability given to her by the crack in her room, Amy's remembrance of her parents and Rory undid their erasure in the rebooted universe. The Doctor, however, remained erased until Amy remembered him and their adventures and brought him and the TARDIS back. Despite everything being repaired, the Doctor remained clueless as to what was responsible for the destruction of the TARDIS in the first place. (TV: The Big Bang)

Notable cracks
Around Easter of 1996, a crack in Amy Pond's bedroom wall connected it to an Atraxi prison. This crack also erased Amy's parents from existence, and Prisoner Zero was able to escape through it to Earth from the Atraxi prison. The Eleventh Doctor closed this crack by widening it with his sonic screwdriver. (TV: The Eleventh Hour, The Big Bang) Cracks also appeared on the side of Starship UK in the 33rd century (TV: The Beast Below) and in the Cabinet War Rooms in 1941. (TV: Victory of the Daleks)

Another crack opened to a vast size aboard the spaceship Byzantium in the 51st century. It erased Crispin, Marco, Pedro, Phillip and many Weeping Angels from existence, then closed. The Weeping Angels had feared it and attempted to escape, only to be dropped into it after they had absorbed all of the Byzantium's energy, disabling the ship's artificial gravity. The Angels, combined, were a sufficiently complex space-time event to seal the crack for a while. (TV: Flesh and Stone)

According to Rosanna Calvierri, she and the other Saturnynians fled Saturnyne because of the "silence" they saw through some of the cracks. They fled through one of the cracks to "an ocean like ours" on Earth, after which the crack closed behind them. Just before the Doctor left Venice, the Doctor heard an abrupt silence; the previously busy market had suddenly become empty. (TV: The Vampires of Venice)

There was a crack in the Silurian base beneath the Earth in 2020. The Doctor, Amy and Rory found it while leaving the base. Examining it, the Doctor reached inside the crack for "shrapnel" from the original explosion, and retrieved a burnt piece of the TARDIS. Before leaving, Rory was fatally shot by Restac, and his corpse came in contact with the light from the crack. Despite Amy's protests, the Doctor left Rory behind. The crack subsequently absorbed Rory and erased him from existence. The Doctor still remembered him and mentioned him later, (TV: Vincent and the Doctor) and the engagement ring which he had bought Amy still existed in the TARDIS. Amy lost all recollection of Rory due to the crack directly affecting her past. (TV: Cold Blood)

There was a crack in Craig Owens' flat in 2010 in the kitchen wall, next to the fridge. Shortly after the Doctor left the flat, the Time Field energy began to emit from the crack and it began to expand. (TV: The Lodger) Craig and his girlfriend Sophie were later revealed to still exist. (TV: Closing Time)

Another crack appeared in the TARDIS itself whilst it was parked next to Amy's house on 26 June 2010. The TARDIS monitor read the time and place, and the glass cracked into the shape of the cracks. This was followed by a sinister voice rasping, "Silence will fall". (TV: The Pandorica Opens)

A crack appeared on one of the walls in the temple of Artemis in 1929. (AUDIO: The Hounds of Artemis)

Some time in the 41st century, a crack appeared on a tank that held a Dalek Mutant. (COMIC: The Only Good Dalek)

On the Minotaur's prison ship, the ship generated a series of rooms, one for each person who got transported inside, containing their worst fear. While he was on board the ship, the Doctor discovered a room of his own, (TV: The God Complex) which contained the illusion of a crack in time. He intuitively dreaded that his business with the cracks in time was not over yet, since they had weakened the integrity of the entire universe and left "scar tissue". His fear was justified and later confirmed. (TV: The Time of the Doctor)

A residual crack on the planet Trenzalore was used by the Time Lords to reach out to the universe from where they were trapped in a pocket dimension in an attempt to return. The Doctor spent hundreds of years defending the planet and crack as he refused to restore the Time Lords as it would cause the Last Great Time War to restart — but also refused to abandon the people of the town of Christmas to the armies of his enemies surrounding the planet. Eventually Clara Oswald used the crack to implore the Time Lords to save the Doctor who was dying of extreme old age due to having no more regenerations. They were able to move the crack and use it to grant the Doctor a new cycle of regeneration before closing it, changing the future of the Doctor and Trenzalore. (TV: The Time of the Doctor)

Other time fields and cracks
The phrase "time field," as well as "cracks in time," was used in relation to a number of temporal phenomenon that had different properties in different situations.

The Third Doctor's time sensor detected disturbances in the time field, serving as a means of locating the Master's TARDIS. (TV: The Time Monster) The Sixth Doctor used his TARDIS to create a competing time field to prevent a Dalek time machine from dematerializing, which constituted the TARDIS and Dalek ship trying to materialize at the same co-ordinates in the Time Vortex. (AUDIO: Patient Zero) The Eighth Doctor was sensitive to disturbances in time-fields. (COMIC: Ophidius)

The temporal manipulation achieved by Whitaker involved the use of a time field for the reversal of time. (TV: Invasion of the Dinosaurs) Folly's prison had a time field that made would-be escapees experience time longer: one minute outside the field was a week within the field. Elliptical warp drives would spasm within the field. (AUDIO: Doing Time)

Sacrificing his life, Jamie McCrimmon destroyed a worldshaper, creating a time field that fast-evolved Marinus into Mondas with aeons passing in minutes across the planet. (COMIC: The World Shapers) Disruptions in Earth's temporal field threw off a series of parallel Earths, also helped by an attempt to mask the planet with a time-field. (COMIC: 4-Dimensional Vistas) Monan was caught in a rupture of temporal radiation and split into multiple variations all occupying the same co-ordinates. The most advanced of the various Monan civilisations was able to control the shifting time fields and conquer/rehabilitate their ancestors. (AUDIO: Square One) Jodafra believed the Horde had manipulated the temporal fields around Oblivion, erasing it from the memory of the universe. (COMIC: Oblivion)

The Library on Kar-Charrat was protected by a time barrier projected by a time field generator; (AUDIO: The Genocide Machine) the perimeter of a time loop was interchangeably referred to as a time field, time threshold, and time barrier. (AUDIO: The Feast of Axos) The Garvond hoped to feed on and ravage the "field of times." (PROSE: The Dimension Riders)

The skull of Vilus Krull existed in a para-chronic time field, meaning it existed partially outside of the continuum. (AUDIO: The Dark Flame) The Windigo, described as a "Time Manipulator," was able to paralyse time-fields with its scream, effectively freezing people between seconds. (COMIC: Bad Blood)

The time fields of Skaro were out of alignment when the planet was put into a time lock, causing various time jumps between the different times. (AUDIO: The Lights of Skaro)

The time field was among the various defenses employed by the Time Lords to protect Gallifrey. Bennus noted that none of Gallifrey's defenses, including the time field, would be able to withstand the impact of the Thousand Worlds which the Daleks planned to forcibly crash into Gallifrey at fifty times the speed of light. (AUDIO: The Heart of the Battle) The Time Lords had earlier used time-fields around Skaro to control the timeline during the Fourth Doctor's interference in the creation of the Daleks. (TV: Genesis of the Daleks, PROSE: A Device of Death)

Charley Pollard described a time fissure as a crack in time, (AUDIO: The Time of the Daleks) with the Tenth Doctor's TARDIS falling through a "crack in time" which led to Pete's World. (TV: Rise of the Cybermen) Skak's attempts to release Ephnol from his temporal imprisonment caused a crack in time. The crack caused the temporal displacement of both the house of John O'Brian in 2009 and a Victorian house from 1884, swapping them. The Bannerman Road gang helped Deathy to close it before it spread all over the world. (AUDIO: The Ghost House)

Behind the scenes

 * The time crack was inspired by a crack Steven Moffat saw in his son's bedroom. It resembled a smiling mouth.
 * In 2010, NASA found what appears to be a crack shaped similar to the one in Doctor Who in the middle of the Milky Way.
 * According to Russell T Davies, the Doctor's closing of the cracks also closed the Cardiff Rift.
 * In TV: The Vampires of Venice, when the Doctor saves Venice, there is a sliver of sunlight on one of the clouds in the sky, which is a very similar shape to the cracks in time. This has led some fans to believe that it really was a crack, while others believe that the shape of the sliver of light was just a coincidence. The latter is supported by the fact that the sliver of light moves with the clouds, and slightly changes shape and orientation as it moves, like an ordinary sliver of light.
 * In TV: Journey to the Centre of the TARDIS, the time rift aboard the TARDIS bore a resemblance to the cracks in time caused by the explosion of the TARDIS.
 * In TV: The Witch's Familiar, when the Dalek city collapsed, due to the decaying Daleks of the Dalek Sewers being affected by regeneration energy, the floor below the Red Supreme Dalek broke apart in the shape of a crack in time.