Quantum Time-Locks (霊子記録固定帯, Reishi Kiroku Kotei-Tai?, lit. "Spiritron Record Anchoring Bands") are a type of "universal" event implicated in the culling and management of Adjacent Worlds (並行世界, Heikou Sekai?). The static course of history locked into place through these Quantum Time-Locks is, in the Thaumaturgical community of the modern world, referred to as the Human Order Foundation (人理定礎, Jinri Teiso?, lit. "Foundations of the Rationality of Man"). The imposition of Quantum Time-Locks is one of the functions performed by the World.
A Quantum Time-Lock is a "universal" event iterated at regular intervals within a domain for the purpose of anchoring "the average expression of phenomena and occurrences" as immutable absolutes within a confirmed History.
In the Prologue of the Altera Route in Fate/EXTELLA, it is stated that the intervals between Time-Locks are a century in scale, but Fate/EXTELLA Material indicates that two Time-Locks in fact manifested between the beginning of the game and the ending of True Nero Route—separated by a bit more than a month in time.
Though the "Universe" (宇宙, Uchuu?) permits the birth of unlimited possibilities, countless Adjacent Worlds, and divergent developments of history, as the unrestricted propagation of this process would quickly exhaust the Universe's lifespan, those extraneous Worlds (世界, sekai?) removed of the category of "timelines characterized by strength and stability" are periodically culled (伐採, basai?) by the existence known as the World (世界という者, Sekai to Iu Mono?, lit. "the thing called the World") so as to prevent the needless expenditure of energy. The facilitation of this process is referred to as the Conservation of Phenomena (事象保存, Jijou Hozon?), effected by way of a heuristic audits (集計, Shukei?) of cumulative timeline survivability (進むと可能性, susumu to kanousei?, lit. "prospects and potential")—judging the persistence of a timeline's Parallel Worlds (平行世界, heikou sekai?) across the subsequent century.
The Moon Cell Automaton has concluded that the means by which the Human "Universe of Awareness" (認識宇宙, Ninshiki Uchuu?)—fundamentally unstable by nature—is stabilized across Past, Present, and Future lies in the execution of "culling" and the formation of "records" (記録帯, Kiroku-tai?, lit. "Recording Bands").
If left alone, the Great Tree Known as Time (時間という大樹, Jikan to Iu Daiju?) will branch without restriction, and the behavior of culling serves to remove those divergences that are unnecessary, leaving only the "trunk" to advance. This is the simplest image by which to comprehend the phenomena. Worlds that lie within the "trunk" are said to be "comparable" (他と同じ世界, hoka to onaji sekai?, lit. "Worlds comparable to the others") of "Foundation" (世界の基盤, Sekai no Kiban?, lit. "Foundation of a World"); the human civilizations extant within them largely resemble one another in expression and format.
As worlds that advance too far into ruin or prosperity can only tend toward immutable outcomes, they are considered to be bankrupt of Parallel Worlds, and therefore culled; consequently, that which is preserved and anchored as absolutes by the manifestation of Time-Locks are described to be "the Average Expression (平均値, heikin-chi?, lit. "Average Values") of phenomena and occurrences"—both because the contents of preserved realities tend to be "commonplace" amongst Adjacent Worlds, and because their outcomes on average aren't biased toward positive or negative valence.
Fate/EXTELLA states that the energy required to account for the ceaseless proliferation of unnecessary worlds exists nowhere within this "Dimension" (次元, Jigen?), and that the Dimension itself may eventually exceed capacity if propagation persists unchecked. Furthermore, absent of culling processes, the Earth can persist at its present level of civilization for only another century before the Solar System dissolves beneath the sheer volume of the data produced by humankind. With culling processes safely in place, however, it's likely that the status quo can be sustained for another hundred million years.
The purview of events to be registered to record in an upcoming Quantum Time-Lock may be dictated only those who live within the era. Intervention from the past or future is incapable of directly influencing the formation of a Time-Lock. In Fate/EXTELLA, the factor that determines the purview of a Time-Lock is referred to as "Observation" (観測, Kansoku?).
Any history that has been secured as a Time-Lock (固定帯, kotei-tai?, lit. "anchoring band") become as an existence impervious to interference from the past and future; events or phenomena that exist within the purview of the anchoring band are utterly immovable. Hypothetically, if one were to move to a chronological position in the past of an "anchoring band" to the end of modifying history, as time progresses unto the Time-Lock, history would be forcibly corrected (強引に復元, gouin ni fukugen?, lit. "forcibly restored") to its state of record.
In those universes wherein Quantum Time-Locks are imposed, the "outcomes" that have been registered to anchoring bands are categorically unchangeable. Thus, that which would be open for time travelers to modify would be invariably restricted to "process."
For example, let us presume that the "outcome" that "Britain was destroyed" is secured as a matter of record. In the circumstance that a process wherein "Britain comes to prosper; its wars are concluded; and happiness is granted to its people" is successfully brought about, in the moment that history advances unto the anchoring band, the outcome whereby "even so, Britain came unto its destruction" manifests.
To rephrase, it is potentially possible that by some immense undertaking, the course of the History of Man could be fundamentally denied by the successful revocation (破壊, hakai?, lit. "destruction") of a "Quantum Time-Lock"—but even by this method, that which is denied is restricted to "the History of Man that falls subsequent to the anchoring band." As seen in Fate/Grand Order, interference of this scale requires energy that is at least equivalent to a Holy Grail, and has a catastrophic effect on the History of Man to the extent that it is reduced to a mass of arbitrary possibilities. A total rewrite of history would require more energy than exists on Earth, a limitation which Goetia overcomes by the Incineration of Humanity.
Differences in Localization
In the English localization of Fate/EXTELLA, the explanation of Quantum Time-Locks in the Prologue of the Altera Route subtly differs from the Japanese text. Differences may be roughly summarized as follows:
- "Solitary Otherworlds and / or worlds that advance too far into ruin or prosperity are bankrupt of Parallel Worlds / Branching Potential, tending toward immutable outcomes. Being incapable of guaranteeing survivability, these timelines are culled by the World, as the energy to account for the proliferation of unnecessary worlds exists nowhere within the Dimension. As of the manifestation of a Time-Lock, past histories become immutable."
- Proliferation of branches is a behavior that a timeline automatically engages in, without external input.
- "Worlds that advance too far into ruin or prosperity" lack Branching Potential, and are biased toward singular outcomes (either of positive or negative valence). They are inherently incapable of further branching.
- The Dimension's energy is used to "account" for the proliferation of branching timelines.
- When a Time-Lock manifests, minimum Branching Potential timelines are "culled."
- The agent that enacts Time-Locks is referred to as "the World." The domain in which Time-Locks exist is referred to as "the Dimension."
- As of the manifestation of a Time-Lock, "past histories" become immutable.
- "Worlds where the future cannot be changed and / or evolved too fast / crumbled too quickly are effectively Dead Ends with predetermined outcomes. The Dimension contains a finite amount of energy, and does not hold energy to spare for the creation of further divergences from Dead End worlds. Only outcomes that would not cause undue difficulty in managing the next generation are supported; other futures are closed by the Dimension. As of the manifestation of a Time-Lock, future histories become immutable."
- Proliferation of branches is a behavior that a timeline engages in only when allotted energy by the Dimension.
- "Worlds that evolved too fast or crumbled too quickly" are "Dead Ends" with predetermined outcomes, where the future cannot change. However, they are capable of further proliferating into "new worlds" if continuously allotted energy by the Dimension.
- The creation of worlds expends the Dimension's energy.
- When a Time-Lock manifests, timelines recognized as "Dead Ends" are closed to the future, and cease to be allotted energy for branch proliferation.
- The agent that enacts Time-Locks is referred to as "the Dimension."
- As of the manifestation of a Time-Lock, "future histories" become immutable.
In the Avant Title of the Fate/Grand Order - Accel Zero Order event, Lord El-Melloi II makes references to certain terminology pertaining to the cosmology of Adjacent Worlds and Quantum Time-Locks, available to his comprehension as a consequence of temporarily becoming one with a Heroic Spirit. It is unclear if these terms are in general parlance within the Thaumaturgical community.
In Fate/EXTELLA Material, Items Permissible to Revision (編纂事象, Hensan Jijyou?) and Items Designated for Removal (剪定事象, Sentei Jijyou?) are collectively referred to as concepts implicated in the Operation of Adjacent Worlds (並行世界の運営概念, Heikou Sekai no Unei Gainen?). However, their relationship with the 2nd Magic (第二魔法, Dai Ni Mahou?) is unclear.
- Adjacent Worlds (並行世界, Heikou Sekai?) refer to divergent timelines that advance in adjacence to one another. In Fate/EXTELLA, it is stated that a World qualifies for culling if it entirely lacks the potential to diverge into Adjacent Worlds. Incidentally, Archimedes' capacity to travel between Adjacent Worlds is referred to as Sliding (並行移動, Heikou Idou?).
- "Adjacent Worlds" are terminologically distinct within the canon from Parallel Worlds (平行世界, Heikou Sekai?), which appear to refer to timelines that advance in perfect parallel with no relationship of divergence.
- The Primary Branch (大幹, Daikan?) or Trunk refers to the cluster of Adjacent Worlds (並行世界群, Heikou Sekai-Gun?) that form the central axis of the Great Tree Known as Time (時間という大樹, Jikan to Iu Daiju?) -- comprising of the confirmed (確定, kakutei?) pathways of the History of Man; that which remains as of the completion of culling (伐採, basai?) processes. The worlds of Fate/Zero and Fate/Grand Order are stated by Romani Archaman to "lie near the center" of this cluster -- amongst many that closely approach one another in their historical course. Worlds within the Primary Branch are said to exist along their "proper axis" (正しい軸, Tadashii Jiku?), representing "the Average Expression (平均値, heikin-chi?, lit. "Average Values") of phenomena and occurrences" across the timelines of humanity.
Items Permissible to Revision
- Items Permissible to Revision (編纂事象, Hensan Jijyou?, lit. "Editable Items / Phenomena") is a category name applied to the set of worlds within the Primary Branch. Refers to timelines wherein, outside of the Outcomes (結果, Kekka?) confirmed by a Quantum Time-Lock, the Processes (過程, Katei?) leading up to an outcome may still be modified by time travelers. Beyond the circumstance that an "immense undertaking" overturns a Quantum Time-Lock, however, confirmed Outcomes within these timelines are immutable, regardless of interference from the past or future. Prior to the manifestation of a Quantum Time-Lock, all open and unculled timelines fall under this category.
Items Designated for Removal
- Items Designated for Removal (剪定事象, Sentei Jijyou?, lit. "Items / Phenomenon for Removal") is a category name applied to divergent timelines that have come to exist as realities entirely distinct from others (完全に別世界になり, kanzen ni betsu-sekai ni nari?) -- that is to say, Otherworlds (異世界, Isekai?) wherein the "Foundation" (世界の基盤, Sekai no Kiban?, lit. "Foundation of a World") is sufficiently deviant that its civilization no longer resembles those within the timelines of the Primary Branch. Pruning can also occur if the divergence between branches is so small as to be irrelevant. As the name implies, these realities are designated for culling.
- In Chapter 11 of the Shinjuku Singularity of Fate/Grand Order, Leonardo da Vinci explains that within timelines removed of the established History of Man, Human Order is inactive, and defensive measures of the planet normally rendered by the Counter Force are therefore non-extant. It is as a consequence of this that James Moriarty is able to -- within the context of a timeline designated for culling -- implement his plan to physically annihilate the planet.
- In Fate/EXTELLA, a set of overlapping criteria is outlined for the culling of Items Designated for Removal as of the manifestation of a Quantum Time-Lock:
- The choices of a timeline's inhabitants can no longer effectively impact its future; possibilities no longer exist.
- The past of a timeline can no longer be undone.
- Continuous advancement unto ruin or prosperity has occurred, to the extent that the World has been bankrupted of Parallel Worlds (平行世界, heikou sekai?), and its future has been consequently rendered immutable -- inevitably approaching utopia or destruction without deviation.
- As of a heuristic audit of cumulative survivability prior to the fall of a Quantum Time-Lock, a given World fails to meet the qualifications to ensure "the operation of the subsequent era" (次の時代の運営, Tsugi no Jidai no Unei?) within a century's time.
- Refers to a domain that encompasses space and time. In the world of Fate/EXTRA CCC and Fate/EXTELLA, two varieties of existence are referred to as "Universe":
- "Universe of Observation" (観測宇宙, Kansoku Uchuu?) refers to a domain of reality wherein the Concept of Time (時間の概念, Jikan no Gainen?) is expressed as "Time Within Conscious Recognition" (認識される時間, Ninshiki-sareru Jikan?); also referred to as "Universe of Awareness" (認識宇宙, Ninshiki Uchuu?). Per the circumstances of human consciousness, the events of the Past, Present, and Future cannot in this expression of time be distinguished as categorically discrete, as the Future continuously passes unto the Present, and the Present into the Past. In exchange for an incapacity to perceive that which lies beyond the Present, one whose awareness is attuned to the "Universe of Observation" obtains the capacity to alter the Present referred to as Tomorrow.
- "Universe of Record" (記録宇宙, Kiroku Uchuu?) refers to a domain of reality wherein the Concept of Time is expressed as "Time Submitted to Record" (記録される時間, Kiroku-sareru Jikan?) -- such that the Past, Present, and Future can be distinguished as categorically discrete entities per a chronological record of proceedings. The timelines represented within the Adjacent World Simulator (並行世界シミュレーター, Heikou Sekai Shimyure-ta-?) of the Moon Cell Automaton may be collectively considered a "Universe of Record."
- Per Fate/EXTELLA Material, the "Universe" discussed within the context of Quantum Time-Locks refers to Humanity's "Universe of Awareness." It is however unclear if this phrase is synonymous to the term "Dimension" (次元, Jigen?) referenced in Fate/EXTELLA; or how indeed the "capacity" or "energy limitations" inherent to the "Universe" restricts the propagation of timelines.
Fate/Prototype: Fragments of Sky Silver
- If Manaka Sajyou had succeeded in fulfilling Saber's wish of an eternal Britain, the Human Order Foundation would have collapsed and the modern world would have been destroyed.
- By way of the establishment of Singularities (特異点, Tokuiten?), Goetia overturns seven of the most significant Quantum Time-Locks within the History of Man so as to facilitate his plan.
- In the context of Fate/Grand Order as a whole, Quantum Time-Locks are referred to as Human Order Foundations (人理定礎, Jinri Teiso?, lit. "Foundations of the Rationality of Man") as they form the premises upon which the rationality of humanity necessarily operates. In their absence, the History of Man is itself reduced to chaos of arbitrary possibilities. The Lostbelts function similarly, albeit on a much more drastic scale such that their revised versions of the History of Man are all but unrecognizable. Only the presence of the Fantasy Trees keeps them from being immediately culled.
- In Fate/EXTELLA, the objective of Archimedes was to manufacture an outcome whereby "Moon Cell is destroyed" prior to the manifestation of the coming Quantum Time-Lock -- establishing a reality premised upon this condition.
- Whereas originally, such a development could not occur, Archimedes repeatedly shifted between realities to the end of achieving his goal. From Archimedes' perspective, so long as the operation of Moon Cell could be entirely brought to a halt prior to the fall of the subsequent Quantum Time-Lock, victory would be his.
- However, even if there were outcomes in which Archimedes was victorious, a route in which the complete termination of Moon Cell's processes occurred could not be reached. In the meantime, the Protagonist was able to confirm "an average world that bears the greatest potential" -- establishing the purview of the coming Quantum Time-Lock. Archimedes' machinations were consequently brought to ruin.
- Incidentally, Quantum Time-Lock A manifested as of the start of the primary story-arc in Extella, when "the Protagonist enters the Stone Chamber of the Titan with Archimedes, and is split into parts"; Quantum Time-Lock B manifested as of the ending of the True Nero Route.
- Regardless of the actions taken by Archimedes between these two points in time, the "Outcome" was already decided.
 Fate/EXTELLA Material - Quantum Time-Lock
Quantum Time-lock [Existence]
Spiritron Record Anchoring Bands (霊子記録固定帯, Reishi Kiroku Kotei-tai).
An event that manifests at regular intervals for the purpose of anchoring the Average Expression (平均値, heikin-chi?, lit. "Average Values") of phenomena as absolutes.
This universe permits the birth of unlimited possibilities, numerous adjacent worlds, and divergent developments of history.
However, as the unrestricted propagation of this process would exhaust the lifespan of the universe, at set intervals, those extraneous worlds (世界, sekai?) removed of the category of "routes characterized by survivability and stability" are culled (伐採, basai, lit. "cull" / "prune"), so as to prevent the needless expenditure of energy.
The Mooncell has concluded that the means by which our Universe of Awareness (認識宇宙) -- fundamentally unstable by nature -- is stabilized across the Past, Present, and Future lie in the execution of "culling" and the formation of "records" (記録帯, Kiroku-tai, lit. "Recording Bands").
If left alone, the Great Tree Known as Time (時間という大樹, Jikan to Iu Daiju?) will branch without restriction, and the behavior of culling serves to remove those divergences that are unnecessary, leaving only the "trunk" to advance. This is the simplest image by which to comprehend the phenomena.
Any history that has been secured as an anchoring band (固定帯, kotei-tai) become as an existence impervious to interference from the past and future; events or phenomena that exist within the purview of the anchoring band are utterly immovable.
Hypothetically, if one were to move to a chronological position in the past of an "anchoring band" to the purpose of modifying history, as time progresses unto the position of the "anchoring band," history would be forcibly corrected (強引に復元, gouin ni fukugen?, lit. "forcibly restored") to its state of record.
In those universes wherein Quantum Time-Locks are imposed, the "outcomes" that have been registered to anchoring bands are categorically unchangeable. Thus, that which would be open for time travelers to modify would be invariably restricted to "process."
For example, let us presume that the "outcome" that "Britain was destroyed" is secured as a matter of record.
In the circumstance that a process wherein "Britain comes to prosper; its wars are concluded; and happiness is granted to its people" is successfully brought about, in the moment that history advances unto the anchoring band, the outcome whereby "even so, Britain came unto its destruction" manifests.
One or two -- or any number of lives might be saved.
However, modification to the overall course of the History of Man (人類史, Jinrui-shi) is decisively beyond possibility.
These are the Quantum Time-Locks -- those existences referred to within Thaumaturgical Society as Human Order Foundations (人理定礎, Jinri Teiso?, lit. "Foundations of the Rationality of Man").
To rephrase, it is potentially possible that by some immense undertaking, the course of the History of Man could be fundamentally denied by successful revocation (破壊, hakai, destruction) of a "Quantum Time-Lock," but even by this method, that which is denied is restricted to "the History of Man that falls subsequent to the anchoring band."
The purview of a "Quantum Time-Lock" due to manifest may be dictated only those who live within the era. Intervention from the past or future is incapable of directly influencing the formation of a Quantum Time-Lock.
 Fate/EXTELLA - Chapter Altera - Prologue
Upon the Earth, there is exists the hypothesis of "Adjacent Worlds."
The World is not one; rather, like a reflection in a pair of opposing mirrors, it infinitely unfolds. Consequently, there cannot exist only a single future -- or so it's thought. In other words --
Let's explain it like this. The you that exists right now can be described as a you that exists somewhere within this flow of time.
It's probably difficult for you to envision. After all, it's impossible for humans to even perceive "the Boundaries Between Worlds" (世界の壁, Sekai no Kabe?) -- much less what lies beyond.
So, how about I rephrase? Worlds that run adjacent are essentially as "possibilities."
Conclusions that may be possible.
Bonds that were abandoned.
Options that went unnoticed.
Divergent futures, wherein "what ifs" such as these were permitted. It is indeed these "realities in which the future was altered" that are referred to as Adjacent Worlds.
The you who is now alive --
By the actions of the you who exists here and now, the course of the World can shift in any number of ways.
This is proof that "possibility" (可能性, kanousei?) is itself still alive; positive evidence that your World still lies upon its "proper axis" (正しい軸, Tadashii Jiku?).
In converse: For those Worlds wherein the act of choice can no longer impact the future, Parallel Worlds cannot exist.
Such timelines merely advance.
Losing even the possibility of undoing the past, they become distinct, solitary Worlds.
Their manifestation is a necessary evil, structurally mandated.
In those worlds where choiceless choices incessantly persist, the form of the "World" familiar to you cannot endure.
There should exist worlds ruined by the repetition of choices in mortal error, yes?
There should exist worlds that excessively advanced their civilization by way of continuous innovation, yes?
But once a World arrives at such a state, it can no longer be counted as "a World comparable to the others" (他と同じ世界, hoka to onaji sekai?). If the Foundation of a World (世界の基盤, Sekai no Kiban?) has deviated, it becomes that which is known as an Otherworld (別世界, Betsu-Sekai?, lit. "distinct reality").
But why do such realities become solitary? Shouldn't it be that whatever the future, the possibility of adjacent advancement persists?
Unfortunately, this isn't the case. The energy to account for the proliferation of unnecessary worlds, exists nowhere within this Dimension (次元, Jigen?).
That is to say, the ceaseless proliferation of Parallel Worlds may eventually exceed the capacity of the Dimension as a whole.
Parallel Worlds are a necessary existence, but they cannot be let to freely multiply.
It's a very rough estimation, but should the Earth persist at its present level of civilization for another century, it's likely that the Solar System will collapse.
However, the reality is that we live and multiply. The Solar System hasn't yet dissolved (緩和, kanwa?, lit. "loosen / relax / alleviate") before the sheer volume of data that we produce, and it's likely that the status quo (今の方式, ima no houshiki, lit. "the present formulation / system"?) can be sustained for another hundred million years.
And the principle behind it is simple. To a certain extent, the existence known as the World (世界という者, Sekai to Iu Mono?, lit. "the thing called the World") conducts a hueristic analysis (統計, toukei?) of timeline survivability (進むと可能性, susumu to kanousei?, lit. "prospects and potential"), preserving only those Outcomes wherein "the operation of the subsequent era" (次の時代の運営, Tsugi no Jidai no Unei?) isn't impossible.
For those Parallel Worlds judged to be unnecessary -- the future is closed.
In more concrete terms, cumulative audits (集計, Shukei?) are conducted at intervals of a century in scale (百年単位, hyakunen tan'i?, lit. "units of a century"), to the end of identifying and preserving only the possibilities (可能性, kanousei?) of those Worlds capable of guaranteeing "the preservation of capacity for advancement in yet a subsequent century, at bare minimum."
Per the systematic demands (法則, housoku?, lit. "laws") that facilitate the Conservation of Mass (質量保存, Shitsuryou Hozon?), this process could be termed the Conservation of Phenomena (事象保存, Jijou Hozon?).
Thusly, the civilizations of the many extant Parallel Worlds largely refrain from divergence. You can imagine it as a great tree. The worlds permitted to advance are restricted to the center -- comprising the trunk. Those branches that diverge grow and multiply, but eventually succumb to their limitations (限界, genkai?), falling to ruin without reaching a future.
You understand, yes?
Those worlds that advance too far into ruin or prosperity are bankrupt of Parallel Worlds (平行世界, heikou sekai?). Otherworlds (異世界, Isekai?) such as these are little more than blind alleys (袋小路, fukurou-kouji?) whose outcomes are foreordained.
The time of the culling brings a termination to unnecessary possibilities -- the point at which, by force of Observation (観測, Kansoku?), the mutable Histories of the past solidify as a static course.
This is what the Magi of the Old World (旧世界, Kyuusekai?) referred to as Phenomenon Anchoring Bands (事象固定帯, Jijou Kotei-Tai?) -- the Foundations of the Rationalities of Man (人理定礎, Jinri Teiso?).
 Fate/EXTELLA - Chapter Altera (Localization) - Prologue
"Earth scientists have hypothesized the so-called 'parallel worlds,' other versions of Earth and its surroundings, expanding indefinitely like mirrored reflections. If true, that would mean that Earth has not only one future, but many. In other words ..."
"Think of it like this. The 'you' that you are aware of exists somewhere upon this timeline."
"It might sound unreal. Humans aren't equipped to perceive, let alone traverse, the 'wall between worlds.' But what if I put it another way? Think of these parallel worlds as other possibilities."
"Imagine what might have been in your life. Think of the connections that were cut off and thrown away. Options you see now, in retrospect, that yu would never have considered at the time. Picture how your life today might be different had those 'what ifs' come to pass. All those variant futures, in everyone's lives, make up the vast array of parallel worlds."
"Your actions, those of the 'you' in this present moment on this particular timeline, can change the world in any number of ways. That proves such possibilities are alive, and that your world exists on the 'proper axis.'"
"Conversely, a world where the future cannot be changed, regardless of your choices, can have no parallel worlds. Such a world is nothing but a dead end, solitary and singular, with a past as immutable as its future."
"This is a necessary evil, a byproduct of the way parallel worlds are structured together. After all, a world where humanity made radically different choices would bear very little resemblance to the world you know."
"Some worlds may have crumbled by making all the worse choices. Others may have made all the right ones, and rocketed ahead, perhaps too far ahead. In either case, that world can no longer be said to resemble ours, and once a world moves out of sync, it is no longer 'parallel.'"
"'Why would those worlds become solitary,' you ask? 'Could the people in those worlds not still make different choices?'"
"Unfortunately, no. This dimension contains a finite amount of energy, and has none to spare for creating new worlds from the worlds gone so far astray."
"If parallel worlds continued to increase in this manner, their number would eventuallky exceed the capacity of this dimension. Parallel worlds must exust, but in a manageable quantity. By my own rough calculations, and judging by the civilization of Earth alone, this solar system would collapse within 100 years if parallel worlds expanded without limits."
"Seeing as how we do, in fact, live and multiply, the solar system is clearly not oversaturated with possibilities at this time, I extrapolate that this dimension can sustain our existence for the next 100,000,000 years."
"The system works thusly: At regular intervals, the dimension takes stock of the possibilities it contains, and only allows certain outcomes, those that would not cause undue difficulty in managing the next generation, to remain. As for the unneeded parallel worlds, the system closes off their futures."
"Specifically, every 100 years, it calculates how many worlds will last another 100 years, and supports those worlds only. Have you heard of the Law of Conservation of Mass? This could be called the Law of Conservation of Events."
"And so, the civilization in these numerous parallel worlds line up with one another. Think of it all as a giant tree. Only the trunk at the center can grow tall. The branches may bear fruit, but eventually they reach their limit, and fall without reaching the future."
"You understand, yes? There are no parallel worlds for a world that has evolved too fast or crumbled too quickly. Such worlds are merely dead ends whose outcomes are predetermined."
"And so, there is a set time frame in which these branches are trimmed, extra possibilities are removed, and future histories, once fluid, turn to stone. The mages of the old world called this time frame 'the Foundation of Humanity.'"
 Fate/EXTELLA Material - Quantum Time-Lock - Archimedes
In the present work, the objective of Archimedes was to manufacture an Outcome whereby "Moon Cell is Destroyed" prior to the manifestation of the coming Quantum Time-Lock -- establishing a reality premised upon this condition.
Whereas originally, such a development could not occur, Archimedes repeatedly shifted between realities to the end of achieving his goal.
From Archimedes' perspective, so long as the operation of Moon Cell could be entirely brought to a halt prior to the fall of the subsequent Quantum Time-Lock, victory would be his.
However, even if there were outcomes in which Archimedes was victorious, a route in which the complete termination of Moon Cell's processes occurred could not be reached. In the meantime, the Protagonist was able to confirm "an average world that bears the potential greatest" -- establishing the purview of the coming Quantum Time-Lock.
Archimedes' machinations were consequently reduced to little more than seafoam.
Incidentally, Quantum Time-Lock A manifested as of the start of the primary story-arc in Extella, when "the Protagonist enters the Stone Chamber of the Titan with Archimedes, and is split into parts"; Quantum Time-Lock B manifested as of the Ending of the True Nero Route.
Regardless of the actions taken by Archimedes between these two points in time, the "Outcome" was already decided.
 Fate/Grand Order - Accel Zero Order - Avant Title
You're referring to a new Singularity, yes?
But Doctor, aren't those coordinates are identical to that of Singularity F?
Yeah, on the map display of Chaldeas, they are.
But it's at a different location on the Time Axis.
The Singularity that we're currently observing lies ten years prior to the 'Singularity F' that we previously had you investigate.
We haven't yet been able to establish the existence of a Grail on site yet, but observed extremely similar readings.
In the past, is it? But is it really possible that a Grail would appear multiple times in the same location?
Well, this is something that I can't really explain either.
Consequently, I've brought along somebody who seems like they'd be able to.
I see. So that's why I've been called, huh?
Zhuge Kongming ......
No, Lord El-Melloi II-san!
I am indeed familiar with the city of Fuyuki, Japan ......
Or so I'd like to claim.
Unfortunately, the knowledge that I possess is of a history that diverges from that recorded by Chaldea's LAPLACE.
Well, that can't be helped.
Since the incineration of the History of Man, the observations provided by CHALDEAS have been compromised by all sorts of arbitrary 'probabilities.'
Most likely, the timeline that El-Melloi II-kun is a native to just happens not to be viewable.
This world and that .......
It's just about impossible to determine which specific timeline actually represents the proper course of history.
In the end, however, it's fairly clear that our timelines are "worlds that lie near the center, which closely approach one another."
If not for that, I wouldn't have asked for your assistance.
You're referring to the cluster of adjacent worlds (並行世界群, Heikou Sekai-Gun) that fall within a Primary Branch (大幹, Daikan) ......
The "Items Permissible to Revision" (編纂事象, Hensan Jijyou, lit. "Editable Items / Phenomena"), within which the same futures manifest even if some degree of divergence exists, and the adjacent worlds of those Branches fated for destruction, which form as entirely separate realities ...
The "Items Designated for Omission" (剪定事象, Sentei Jijyou, lit. "Items / Phenomenon for Removal").
Sorry to say, but this particular subject is actually outside my area of expertise.
Delving into the matter would entail a discussion of the cosmology of the world that I presently comprehend only as a consequence of becoming one with a Heroic Spirit.
Also, it's largely irrelevant to the subject at hand.
Thus, I'll speak only of matters within my personal realm of experience.
At the least, I'll provide as a premise for discussion an account of "events as they occurred within my reality."
In the records available to you, the city of Fuyuki in the year 2004 is the space-time locale in which very first War of the Holy Grail was fought. However, to my knowledge, the count of the Grail Wars held in the city of Fuyuki numbers at five.
Five times! That many!?
Hm, I see.
In other words, the War of the Holy Grail was held five times.
--- wait. It was held five times!?
A thaumaturgical ritual of that sort of scale, five times!?
How did you people even conceal it!?
You're saying that your reality turned the Grail War into some sort of sports competition, like the Olympics!?
A lovely thought, Doctor, but I'm afraid that isn't how it was.
In our circumstance, it was merely the collaboration of the Association and the Church that permitted the concealment of the War.
(sighing, more calmly)
Y-, Yeah, I thought that'd be the case ......
Sorry about the freakout. Please continue, Professor.
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