World Line Theory, Divergence, Loops, and Kurisu's Deaths and Salvation

This blog post was written when Bazingax asked for my opinion on a conversation going on in the anime series page and my answer got too wordy. XD

Okay, I'm going to explain world lines as I understand them and for the sake of completeness of this blog post the divergence meter and number designations, how I think the first and last episodes fit together, what can be presumed to have happened in some world lines before the time loops occurred, e.g. Kurisu's death, and discuss how the change to the Steins Gate world line worked.

To be honest I have always found what Bazingax is asking about to be some of the most confusing but also most interesting parts of SG. I cannot say with surety whether I fully understand this, but I will try to give what answers I have anyway. M.A.D.company made some good points. I'm going to write my answer from the beginning, though, because that will make explaining things easier for me. My apologies if that means I make some points redundantly, but who knows, sometimes the same things explained in a different manner make better sense to some people. For the sake of saving myself time I am going to be quoting from this LParchive of the visual novel. However, it's rather old, so it was made using the old fan translation patch and not the official JAST translation. Please pardon that.

I will also be referencing the Steins;Gate Official Book (ISBN9784047263741)'s Q&A section. I am still very much a beginner in learning Japanese, so please pardon my rough translation. Any corrections will be gratefully received.

The world line theory

The way I understand it, in Steins;Gate the world line theory is that there are countless world lines with all of the infinite possibilities. However, there is only one world line that is "active" at any given moment.

Bazingax mentioned this article by the admin of the ibm5100.net wiki. Except for the writer's choice of using the word "exist" instead of "active", I think it is more or less correct. And, you could say that the past and present get reconstructed from the point of view of the Observer.  It get's kind of confusing, for example even Reading Steiner said something similar here.  If I were to try to describe it, the world lines that are not "active" exist in a sense but are not "in existence" in the same way. -And, now we are getting into crazy philosophical territory, so further and onwards ;P-

A small note: The scenes in which Suzuha's whole explanation about world lines occurred in were different in the original VN and the anime. In the anime and manga she explains with a rope to Okabe and Kurisu in the Radio Building. In the VN she explains with Mayuri's knitting yarn in the lab. Hooray! Color coding! \^^/

To quote from the VN, Suzuha: "The world's structure was clarified in 2036. It's not the many-worlds interpretation."

S: "The world is made of world lines and attractor fields."

Suzuha takes a red yarn ball out of Mayuri's costume sewing set placed on the table. She holds one end of the yarn and drops the ball on the floor. She stretches out about a meter of the yarn in front of her face to show it to us.

S: "The world's structure is like twisted yarn.

"Several possible worlds are superposition, always branching out infinitely.

"The entirety looks like one piece, but at the micro level, the world is organized like thin intertwined threads. And at the end, those fine threads converge into one. The paths are different, but the ends are the same."

Kurisu: "Isn't that determinism?"

S: "It might be close, but it's a little more rough. It sort of cherry-picks from the many-worlds interpretation and the Copenhagen interpretation."

Okabe: "So the divergences end the same, meaning there's only one world in the end?"

S: "Exactly. And so, the bundle of world lines within the range of convergence make up an attractor field. There are also several attractor fields. This twisted yarn is Attractor Field α. In its range are α World Lines."

Suzuha indicates the yarn she's holding while cutting meter lengths of blue, yellow, and white yarn. She creates a multicolored string.

S: "Blue is Attractor Field β, yellow is γ, and white is δ. Each has several of their respective β World Lines, γ World Lines, and δ World Lines. And there are hundreds of millions of these."

She bundles them together and stretches them out again. The several multicolored yarns intertwine into one fat twisted yarn.

S: "Several attractor fields are superpositioned like this. In each attractor field, the converging result of events is different. They don't interfere. Each remains independent. There's only one if you trace it back to the origin. Attractor fields do converge at a very macro level, but that spans hundreds of years. It's best to think of them as large divergences."

This thread represents Attractor Fields; each strand is a separate Attractor Field, which in turn is made up of numerous strands that represent world lines.

Kurisu: "These superpositioned world lines aren't parallel worlds, are they?"

Suzuha: "No. At the very end, they're just possible worlds that exist simultaneously."

Further, in the Boukan no Rebellion manga, chapter two, they describe the world line theory similarly, as consisting of world lines and attractor fields. It is similar to the parallel worlds theory. However, unlike in that theory, the worlds are not simultaneously active. Like a changing switch, one world line is "on" while the other possible world lines are "off".

I believe this is why Reading Steiner déjà vu and dreams can occur in others because those memories do exist in other "inactive" world lines for them to "recall". The whole big theme of the movie is that "omoi" -a kind of bundled concept of memories, thoughts, feelings, weight that exists in Japanese- are strong enough to even surpass world lines. -Very romantic, right? And, Bazingax, you were wondering if you should watch the movie or not, right? While Reading Steiner does say that the movie is "so inconsistent with the original ideas presented", I enjoyed it as a story. My critical opinion is more or less the same as this review on it. And rather than being inconsistent, I have been thinking it might actually make sense in a way… But that's a topic for another discussion.-

Time travel and the divergence meter and numbers

Just in case people are wondering why Okabe does not encounter himself while trying to save Kurisu the second time in episode 24. Some have explained it as world line convergence correcting time paradoxes sort of thing. Because he did not meet himself on the first trip he won't again on the second. The official guide book gives this answer,

Q29: In chapter 11, at the time when Okabe returns for the second time to 7/28, the first time machine was also returning to then, why did they not meet each other?

A29: About the time travel in chapter 11, [in comparison to] before jumping in the path of the jump, a 0.000001-0.000003% degree of fluctuation occurs in the world line. This error/miscalculation also increases with the length of the jump.

For example, Suzuha's point of departure from 2036 [in the Alpha attractor field] was world line rate of fluctuation 0.000000%. However, her point of arrival in 2010 varying by 0.3-0.5 percent was for this reason.

I find it interesting that the Divergence Meter and the line the Alpha Suzuha arrived from is 0.000000%. A world line that the main story's "active/observing" Okabe never went to himself. To quote her from the VN again,

When Okabe arrives in the first Alpha world line after sending the D-mail about seeing Kurisu dead, which is 0.571024%, she writes this on @channel.

689 Name: JOHN TITOR : 07/28/2010 23:31:58

You're talking about the so-called Grandfather Paradox, huh. That's been disproven. This world line has a divergence of 0.571024% compared to the world line I came from.

In other words she is from 0.000000%. Later, she tells Okabe in an email when he is trying to figure out the difference in his memories from everyone else's after sending the Lotto6 D-mail, 

"I've confirmed that the current divergence value is 0.571015%. I cannot tell what the value was before you changed the past. The reason is because I, like your friends, have no memories of the world line before you changed the past. In the case of physical time travel, memories are conserved even if the world line changes. That's been proven by my very own experience."

And later,

Subject: Re: Re: Memory

Sorry, I forgot to mention the divergence numbers. I have a personal meter that measures them. My original world line in 2036 was calibrated to be 0%. It is, after all, a subjective, relative measurement, not an absolute. In the end, this tool can only indicate the current divergence.

To sum it up, she is talking about how she remembers her world line of 0.000000% even though she has physically traveled to 0.571015%.

In Boukan no Rebellion in chapter four, she looks at the divergence meter and contemplates how it now says 0.337187%, that the number changes when you move from one world line to another and that it has changed from where she jumped from the 0% world line.

So, Suzuha traveled from 0.000000% in 2036. Having no control over which world line and only which time period she ends up in and because of world line fluctuation/disturbance she ended up arriving in 0.571024, but every time Okabe changed which world line was active, it also changed which world line was her arrival world line.

Of course, there is/will be a Suzuha in each of those world lines who tries to jump to the past with the Divergence Meter. However, in each of those world lines the Divergence Meter from 0.000000 will already have been brought to the past and exist. So it will just be passed down again, it will not be created anew, or if the Okabe of that world line does create one, he will set the meter's number to the divergence he saw in that world line on the original meter. For example, If he received the divergence meter in 0.337187 and in the future made another one. Then that one he makes in that world line he would also set to 0.337187.

Summary: The world and time are made up of infinite world lines bundled into attractor fields that each converge to their respective field's own major occurrences. There is only one world line active at a time. The rest exist simply as possibilities. The Suzuha from in the Alpha Attractor Field has always been depicted as coming from the world line 0.000000%, which was subjectively given that number by the Okabe in that world line. This should technically be the start of the Divergence Meter loop in the other Alpha world lines. That is why the meter does not end up reading 0.000000% in every world line, because the idea of it is not conceived anew every time.

About time loops and what could have happened in the very start that triggered the time traveling loop?

Now, I'm pretty sure Bazingax was hoping that there were clear explanations and examples that could be given from the VN. I'm sorry to say there aren't really. The creators left a lot for us to puzzle out. I think that due to the nature of the world lines and time travel in SG a fully-closed time loop that overwrites itself probably does not occur. However, it is true that of the world lines we have seen, Suzuha time travels from the future and that creates a loop. That also logically begs that there must be at least a few world lines -0.000000 being arguably one of them- in which her arriving in that world line's past did not occur, so what happens there to make her time travel in which she ends up in the past of other world lines?

I'm going to quote the ibm5100.net wiki,

Q: At what point does the α World line and the β world line diverge?

A: When SERN realizes the existence of the Phone Microwave and creates a Time Machine. Using Eshron SERN picks up the first d-mail from Okabe which leads them to find the lab with the Phone Microwave.

The β world changes to the α world when the first d-mail gets picked up by Eshron and SERN notices it.

The α world changes to the β world when the mail is deleted from Eshrons database before it is noticed by SERN.

Detailed events showing the divergence to each world line.

Episode 1 ( β -> α world line )

Okabe unexpectedly sends the first d-mail which is picked up by Eshron and stored in SERN’s database.

SERN becomes aware of the first d-mail and finds out about Okabe’s time machine project. SERN captures the laboratory members and seize the Phone Microwave.

SERN analyzes the Time Machine at the lab which enables them to complete their time machine. They use it to create a dystopian future within 2 years.

Daru builds a time machine (Future Gadget 204) based on SERN’s model but dies before making it able to travel back to the future. Suzuha travels back to the year 2010 and crashes the time machine into the radio hall. This causes a chain reaction leading to the α world line. The crash leads to the cancelation of the Nakabachi seminar, Kurisu is no longer able to meet her father and survives. The world diverges to the α world line at this point.

So at the start of that description Kurisu is dead and that leads to Suzuha time traveling, which causes the chain reaction where the attractor fields diverge from each other, …I think? In this hypothetical set of transitionary world lines -they have never been depicted (yet)-, I guess Russia probably gets the Nakabachi thesis at the same time that SERN gets the phone microwave and SERN wins the race…?

Back to quoting the ibm5100.net wiki,

Episode 22 ( α -> β world line )

Before SERN notices the d-mail, Okabe and Daru hack into the database using the IBN5100 and delete all traces of the d-mail.

SERN never finds the lab, and FB does not report about Okabe. The time machine is never finished by SERN at this point.

The SERN Dystopia is no longer a reality and the world line begins to diverge away from the α line.

Suzuha arrives in 2010 from 2036 at the Radio Hall building without crashing the time machine. The world line changes to β at this point

The Nakabachi time machine seminar is never cancelled, Kurisu meets her father. She is killed and her time machine thesis is stolen.

And, thus begins the time loop of β Suzuha time traveling now to prevent WWIII by helping Okabe to prevent Kurisu's death and destroying the thesis. But what about the world lines in which Okabe and Kurisu never meet and he doesn't interfere with her death?

-Note: I just spent some time reasoning about the time loops and about Suzuha's travels in the Alpha attractor field, but in the Linear Bounded Phenogram story focusing on Suzuha, which is arguably noncanonical in some ways but given the divergence 0.337337%, she does reason in her head that loops exist with her father having met her in 2010 and that is why he built the time machine for her to travel in in the future. So, I guess that that is what happens to the world lines in which she lands in the past once the loop has been started. She and Daru meet. She leaves for 1975. Daru in the future builds the time machine and her young self in the future time travels all over again, and so the loop continues until that world line is "deactivated".-

Back to what I was talking about before that long tangent. Are you still with me? ^^; 
Bazingax, wanted to know what caused Kurisu to die before Okabe tried to time travel and accidentally stabbed her -let's say at the very cause-and-effect-beginning of the time loops' forming-, right? Well, the answer is we don't know. Her death is a matter of world line convergence. Even if Okabe did not kill her, her father could have killed her with his knife or something else could have happened -like how Mayuri died in many ways-; example, Kurisu is so shaken up by her father's attack or she is trying to chase after him that she falls down the stairs and breaks her neck. If Okabe saw her dead body, he would have sent an accidental D-mail about it, setting off the beginning of the Alpha time loop, which eventually leads us back to the Beta. If he didn't see it -or if he did but the D-mail was deleted as the main story goes-, then Nakabachi would get away to Russia with the thesis paper and the WWIII of the Beta Attractor Field would occur. Somewhat about this from the official book: 

Q30: About chapter 11, without the existence of the Okabe who killed Kurisu, the Okabe who completes the time machine should not exist. At the same time, without the Okabe who developed the time machine, sending Suzuha to the past Okabe, the result would not be Okabe killing Kurisu, is what I am thinking. Is that not a paradox, a contradiction?

A30: Regarding chapter 11's death of Kurisu and the "Okabe who killed her", it is ultimately only "one possibility". The most dramatic given the way that development formed, but take, for example, time traveling to that scene repeatedly without Okabe killing Kurisu. Just like with Mayuri in chapter 6, the future is converging, even without "Okabe killing her, Kurisu will die in another way". Possibly the Okabe in 2025, while time traveling over and over would face this despair.

Concerning the time machine, because the Nakabachi Thesis, which is the time machine theory thought of by Kurisu, exists, Okabe referenced/used that. In order to avoid the Third World War. To the time machine itself "Okabe's persistence" is irrelevant. In actuality, the one who finally completed the time machine was Daru and no one else.

So, I guess that answer means that no matter how she died, and even if Okabe had not witnessed Kurisu's death scene and gone on his harrowing journey through the Alpha world lines, Daru for some reason or another as an effect of convergence would end up making a time machine...? And, of course, that Kurisu's death is still the first domino falling in causing WWIII.

Summary: Whenever time travel occurs, or even time leaping, it does form a loop. However, unlike in some other time travel stories, I think one could say that every loop in Steins;Gate does have a point of origin even if that point is in another world line. Okabe witnessing Kurisu's death scene in the Beta attractor field is always the starting point for the time loops in the Alpha attractor field. Kurisu's death and her father stealing the paper is always the starting point for the loops in the Beta, and Kurisu's death in Beta will occur regardless of whether Okabe is involved or not.

About how the first and last episode fit together

The first episode starts in divergence 1.130426% the last depicts 1.130205% -and divergences thereabouts-. Most notable is at the start of the story we are already within the time loop. Suzuha has traveled back and lands on the roof. Okabe gets a video D-mail, though this time it seems it was unsuccessful and scrambled. We hear someone, who is very likely a time traveling Okabe, give off an anguished cry. Kurisu is seen in a pool of blood. -Did the time travelling Okabe cry because he was gutting himself or because Kurisu died? The answer is unknown.-

Why did we start the story within the loop? Following the SG logic, it's because 1.130426% was the "active" world line at the time, and narratively it is because this Okabe is our Observer and the one who succeeds in breaking out of the loop, therefore he is the most interesting.

Was the Okabe who time traveled in episodes 23 and 24 the same Okabe as the one who must have time traveled in episode 1? I think probably not, because there is a 0.000221% difference between the two world lines, and the guide book answer #29 I mentioned earlier said it was a "0.000001-0.000003%" difference for the time trips in chapter 11/episodes 23-24. So, that must have been an Okabe with a very similar set of experiences but the main story's Okabe, our Observer, probably did not travel back to 1.130426% himself...?

Not that it really matters for Okabe's reasoning in thinking that he has already seen the time machine on July 28th so he must have gone back then, so it is inevitable to go with Suzuha when she asks him to the first time. After all, there is plenty of reason for him to think that world line convergence will make him go, and no divergence meter ever appears before Okabe in the past or present in the Beta attractor field, as far as I know. Okabe would not know the difference between were he was on August 21st and where he had been on July 28th. He only hears from Suzuha that he needs to go -0.081609% further.

Some more on Kurisu's death in Beta and the need for it

As mentioned earlier, Kurisu's death is a matter of "world line convergence" in the Beta Attractor Field. I think the important thing to the world in the Beta world lines is not whether Okabe witnesses her death or not, but the fact that she dies, her father gets his hands on her printed time machine thesis and defects with it to Russia and this sparks an international arms race to build a time machine with other groups, including SERN, fighting to get a hold of the digital copies of her thesis, eventually leading to WWIII breaking out. -This is explored in the Epigraph Trilogy and will probably also be the main subject of the upcoming Steins;Gate 0 VN and anime.-

However, why does Okabe need to make her appear dead and why does that save her? I'm going to quote from the ibm5100.net wiki because I think the writer did a good job of explaining it. http://ibm5100.net/steinswiki/2011/09/19/steinsgate-episode-23-open-the-steinsgate-qa/

Q: Why can Kurisu only be saved by making her look dead?

A: The Okabe from episode 1 needs to witness Kurisu covered in blood and made to think she is dead. If the past Okabe isn’t made to think she is dead, all the events that lead up to where the future Okabe is (The Okabe in episode 23) would cease to exist.

I think just like how Suzuha's act of traveling to the past could not change the world's attractor field in the Alpha world lines, because even her act has a cause and effect and is caught in the convergence. To change it the very "cause" has to be changed and that cannot be done by the "effect". Okabe had to create a cause that still led to the effect, his journey, that still led to a different result overall.

So, why does this cause the world to change to the Steins Gate world line? The world line changes not only when Kurisu is saved but when the thesis paper burns. As a result of Okabe changing the metal upa to a plastic one. Once again quoting from the ibm5100.net wiki, http://ibm5100.net/steinswiki/2011/09/23/steinsgate-episode-24-acheivementpoint-qa/

Q:At what point does the β world line change to the Steins;Gate world line?

A:When Okabe and Suzuha are returning with the time machine to August 21st (After saving Kurisu).

The time machine returns almost a minute after it departs. After the first attempt to save Kurisu, Okabe and Suzuha return and see the news report about Nakabachi exiling to Russia with the thesis safe in his hands.

The requirements that need to be met to jump to the Steins;Gate world line is to 1)Save Kurisu, 2)Burn Nakabachi thesis that was stolen from Kurisu. When these requirements are fulfilled the world line changes.

Knowing that Nakabachi appears on the news almost a few minutes after the time machine returns, the thesis would have burned a few minutes before which is probably during the same time Okabe and Suzuha were making the trip back.

In case someone's confused, Nakabachi flies to Russia on the 21st.

In the VN, Suzuha explains that the Steins Gate -despite having a Beta Attractor Field divergence number 1.048596%- is like a "valley between attractor fields" and therefore unaffected by any of them. Why this is and how they were able to calculate the existence of this world line, I know of no clue, and I bet we never will be given one, but it will be very interesting if that is discussed in Steins;Gate 0. Ah well, I'm willing to keep suspending disbelief here. ;) I think that perhaps it could be the world line where another attractor field splits off from the Beta attractor field and that is why it is free from following the WWIII route. Then I guess within that new budding attractor field -It probably won't fully split off then until after 2036...?- are the other close world lines like 1.048599, depicted in the Robotics;Notes Legacy Revival manga, and the "R" line from the SG movie, which is described in the movie as having a 0.000001% difference and being entwined with the Steins Gate line but in the Gen Sonzai no A Posteriori  drama CD as not really being a separate world line but that it and the SG line are in a layered state.

One thing I try to remember is that the characters giving the explanations themselves do not know everything, so what they say can be proved wrong at the story's creator's whims.

Summary: The important thing to the Beta world line convergence is that Kurisu dies and her father gains the thesis and is unrestrained in reclaiming his academic glory by becoming the "Father of the Time Machine". That is why Okabe saving Kurisu helps to change the world line. However, Okabe cannot change what he witnessed for that is his past that has put him in this position to save her. That's why a set of events where the paper burns and she only seemed dead is the one world line he can reach outside of the Beta attractor field's pull.

Two Okabe's in the Steins Gate?

Bazingax asked why there are not two Okabe's in the Steins;Gate world line, the one who traveled back to the past, got wounded and therefore ends up in the hospital and a hale one who originally belongs to that world line, since that is a world line where the time machine should never have been built at anytime, right? -Let's ignore the movie for now.- I am also unclear about this part. I think we are supposed to forgive a large part of it as being a story and happy endings coming with miracles, but I suppose some possible answers go back to the world line changes when the thesis burns up and Nakabachi is deemed a sham by the Russians, which means that the international arms race does not occur, which must be just a few short moments after Okabe returns to August 21st. Because of that he is already back in the present while the world line is in process of changing. Therefore he would "overwrite" any Okabe who was already there. And, due to the unique construction of the Steins Gate world line the prior Okabe from before the SG world line was activated must have also had reason to time travel and get stabbed, which is why his wound does not disappear as if by magic, etc.

From the VN, "And right after we got back to August 21st... Right before my eyes, the time machine was enveloped in rainbow light, and disappeared. Suzuha disappeared along with her last smile. That was evidence. Proof that I had reached the Steins Gate. So, I shouldn't be sad that she disappeared."

[…] "When I arrived at this world line, right after seeing Suzuha disappear, the first thing I asked Mayuri and Daru was "Was there any recent murder incident at Radio Kaikan?" While panicking upon seeing me drenched in blood, they answered that no such incident had occurred.

While waiting there for an ambulance, Daru lent me his shoulder and I saw it on my phone through 1 SEG. News that Doctor Nakabachi emigrated to Russia and, during the flight, a fire broke out on the jumbo jet he was riding. On the other side of the LCD screen, Nakabachi was terribly agitated. His appearance of bloodshot eyes, splattering spit whenever he yelled, surprised me with its resemblance to his appearance in Radio Kaikan's passage. To me, his unintelligible rambling was the sign of Operation Skuld's success."

[…] "Now nobody will listen to Nakabachi. For argument's sake, let's say even if Nakabachi still remembers the contents of the Nakabachi Thesis, and writes down another thesis... the person known as Makise Kurisu wouldn't allow it. Since the scientific society undoubtedly trusts the daughter more than the father, she has the ability to deter Nakabachi. At the very least, World War III won't break out over the Nakabachi Thesis."

[…] "Apparently Kurisu reported that I was stabbed to the police, but currently, it doesn't seem the search for the 'missing victim' has progressed any. I heard from Daru that no other murder cases occurred at Radio Kaikan, and after doing some research, I couldn't find any deadly incidents in the Akiba area on that day. […]"

So, Okabe gets back as the world line changes, but it is still a world line in which his time traveling self went back and interfered to save her and in which Mayuri and Daru were on the Radio Kaikan Building's rooftop to meet Okabe. So, I guess perhaps:

-Suzuha travels back in time from 2036, because of the displacement she ended up even there, just like she ended up in many world lines in the Alpha attractor field. -...Yeah, I know that doesn't flow quite right.-

-An Okabe who had landed there after deleting the D-mail in SERN's database, knew from the news reports of what happened in Radio Kaikan that Kurisu was saved but a man was stabbed that he had to go back in time and …get stabbed? In order to let Kurisu being saved happen, since he is the cause even if the effect is already in the past.

-So, when Suzuha appears he goes with her to the past. However, this is all happening in an "inactive" world line. So, when the main story's Okabe returns to Aug 21st and the world line changes moments after, Okabe having the Reading Steiner still has his memories from making that last time travel trip within the Beta attractor field proper.

Or:

Maybe it's just an inherent property of the "valley between attractor fields" world line that it's start is within another world line and it just stems off from there, so it can have that sort of weird stuff like only having one Okabe and Suzuha having stopped there with her time machine and then disappearing when she was no longer needed to create the start of the world line.

Similar to how Okabe exists in the Steins Gate world line in the movie up until a certain day and time and after that he disappears and is wiped from everyone's memory. Perhaps time traveling Suzuha exists in that point of time in the world line up til the moment that she disappears as the futures of 1.130205% and 1.048596% diverge from each other. Yes, that seems like a loophole and may be a contradiction. I'm just throwing it out there. Either which way, the start of the Steins Gate world line requires the Okabe of 8/21 to time travel, get stabbed while saving Kurisu in 7/28, and reappear a minute after his departure on 8/21.

However, back to one of the very first ideas mentioned at the start of this post that the world can reconstruct the past or the present reconstruct itself to correct errors whether by convergence or memory overwrite is apparently also true. Suzuha at one point in the Arc Light at the Point of Infinity drama CD mentions that world line convergence would probably get rid of a distortion like her if she failed after jumping from 2011 and was stuck without fuel in 2010 when there is already a version of her in 2010. Also, when Okabe disappears from the Steins Gate world line in the movie everyone's "active" memories of him are erased as well. Though notably they are only erased from that point on. When Kurisu time leaps back a short time Okabe is still there and everyone's memories are intact.

Summary: The world line seems to have changed after Okabe already just arrived back in 8/21, which is why there is only one Okabe in the Steins Gate world line, because the Okabe from the priorly active world line "overwrites" the former Okabe of the Steins Gate at the moment the active world line changes. Similar to how the world line changed to them having never hacked SERN after they deleted the final D-mail from SERN's database, but the fact that the D-mail was deleted must remain, I think, even in the Steins Gate world line in which Okabe and Daru do not build a time machine for Suzuha to travel back to August 21, 2010 in, the fact that Okabe time traveled back to July 28th remains as evidenced by the fact that Kurisu reported his stabbing and his wound did not disappear when 1.130205/1.130212% "deactivated" and 1.048596% became the "active" world line. How exactly this all works I am unsure.

I feel like I have thought myself into a puddle now. Did any of that make sense? Was my reasoning somewhat sound? I know I rambled, but I hope this was somewhat helpful to someone. ^^;

Further reading

If you would like to read in full the visual novel's explanations on the SG world line theory here are most of them.

Suzuha as John Titor writing about world lines in the VN

• @channel
• @channel1
• @channel2
• @channel3
• Mail1
• Mail2

Click the tabs for content. I figured I would put it this way, to keep the page length shorter. Note: Not all of what Suzuha says on @channel is true, so keep reading. If something doesn't make sense, it probably will later.

http://lparchive.org/SteinsGate/Update%2009/

528 Name: Anonymous : 07/28/2010 22:47:41 Anyway, if you become a time traveler, could you go and meet up with your past self? What would happen if you did?

689 Name: JOHN TITOR : 07/28/2010 23:31:58 You're talking about the so-called Grandfather Paradox, huh. That's been disproven. This world line has a divergence of 0.571024% compared to the world line I came from. Killing my father would warp the divergence of the world line. It would create the possible world where my father is killed, but it's not like it would erase the world where he isn't.

SERN is a particle physics research institution. That hasn't changed in 2036.

[…]

712 Name: Anonymous : 07/28/2010 23:49:45 What are "world lines?" what would happen if you meet yourself on another world line?

[…]

807 Name: JOHN TITOR♦f8VuYnoyWU : 07/29/2010 : 00:50:57 World lines are like an infinite number of rivers flowing parallel. Along the way, many of them diverge. For example, whether or not you post on this message board has no effect on this world line's divergence. But, if you were to be killed by a random attacker, then the world line's divergence would change. However, it probably wouldn't change any more than about 0.000002%. So that nobody misunderstands, I'd like to add that tht means a human is only worth tht much. That value skyrockets in the face of war, major acts of terrorism, etc.

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http://lparchive.org/SteinsGate/Update%2017/

229 JOHN TITOR♦f8VuYnoyWU : 07/30/2010 17:36:29 The Everett Wheeler model is correct. Refer to that for more details. It seems like everyone has a fixed idea about the concept of time itself. It's not like the flow of time is restricted to one-way traffic from past to future. To be more accurate, the law of cause and effect doesn't allow any contradictions. In the case that the effect portion is changed, the accompanying cause is changed so it doesn't fail. That's the reason why there are few people who can recognize the changes in divergence. (Divergence being the ration of divergence of the world line.

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311 JOHN TITOR♦f8VuYnoyWU 07/30/2010 18:09:37 It seems nobody especially felt anything when I said that time does not flow in one direction. That is evidence that people are stuck on a fixed idea. And, as far as I can see, not destroying that fixed idea could become a serious issue. Somehow or other, it seems you understand the reason why the dystopia was constructed. Whenever a momentous incident occurs that would cause divergence to change, the past is reconstructed to prevent contradictions, in accordance with the law of cause and effect. For example, if in this world line, a certain momentous incident were to occur, causing a significant change in divergence, we would be transferred to World Line B. In this world line, this online bulletin board, @channel, unfortunately never came into existence. In this case, all of your memories up until now of reading and posting on @channel would disappear, to be overwritten by memories of you doing something else. This is, in short, proof that by changing the present, you can change the past. I explained SERN's situation yesterday. If you want to supplement that explanation, then you have no choice but to believe what they say. They have already succeeded at the creation of micro-black holes.

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320 TITOR♦f8VuYnoyWU : 07/30/2010 18:15:19 > > 314 I see, so you're questioning how I've been designating numbers. Reconstruction of the world and alteration of people's memories I think they're essentially the same thing, but why do you seem so intent on saying they're different? With a few exceptions, people who can recognize the change of world lines don't exist. Reconstruction is over at the exact point the world line changes.

[…]

http://lparchive.org/SteinsGate/Update%2018/

649 Anonymous : 07/31/2010 07:25:46 More importantly, I want to hear more about the many-worlds interpretation. In 2036, it's been proven, right? How did they prove it?

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654 Hououin Kyouma : 07/31/2010 07:37:53 > > 650 Doing that would make you no better than Titor. If you're prepared to do that, then go ahead. Titor, I want to ask you, but did World War III take place? What was your reason for coming to this time in the first place? Did you get an IBN 5100?

[…]

659 JOHN TITOR♦f8VuYnoyWU : 07/31/2010 07:50:00 My objective for coming to this time is, as I've already explained, to change the future. I'm posting on this bulletin board like this to sound the alarm. Perhaps it won't have any meaning due to the convergence of world lines, but it's okay if it works without anyone noticing. > > 654 What's this about World War III? Could that also be something you've seen me saying in a different world line? I would like to talk to you once at your own pace. I'll write a reply if you give me your mail address. Of course, if anyone else besides Hououin wants to mail me up front, I'll be waiting. Because, as of now, I've only been getting hate mail. Here's my contact address once more:

john&titor@egweb.ne.jp

http://lparchive.org/SteinsGate/Update%2019/

In the mail, I question the differences in his posts from 10 years ago and now. He doesn't seem to be in contact with the Titor who posted 10 years ago. I only vaguely remember it, but it went primarily like this: 2015, World War III breaks out, many people die. 2036, the world is contaminated from nuclear warfare. He time traveled from 2036 to 1975 to obtain an IBN 5100. Its purpose was to revive technology lost in World War III. The IBN 5100 has a hidden function: The ability to debut IBN's special proprietary computer language from before APL and BASIC. The only ones who know that fact are certain IBN engineers, so this function does not appear in the manual. In 1998, Titor met his young self and his parents from his early life in America. Titor aspired to be a time traveler as a soldier. Titor is an American. Furthermore, several future events that Titor posted about in 2000 came true. The Peruvian coast earthquake in 2001, the election of a new pope, the outbreak of the Iraq War, China's advances in space, and so forth. Though he talked about all of them vaguely, they all came true. On the other hand, others failed to come true. For example, the Year 2000 Problem, civil war in America, the cancellation of the Beijing Olympics, the inauguration of America's first female president in 2009, and so forth. Let's ask him why those predictions didn't come true.

http://lparchive.org/SteinsGate/Update%2021/ Subject: Are you being honest?

If what you wrote in your mail is all true, then it's very interesting indeed. Particularly concerning the IBN 5100's hidden ability, which I have not mentioned to anybody as of yet. I am indeed surprised by the fact that you know about it. However, I have not gone to the year 2000, though there is a possibility I may go there after this. There are three possibilities:

First, the possibility that the John Titor who appeared in 2000 is my future self. In other words, I, who have returned to 2010, will go to 2000 from here, and write about the things you have told me. But that would cause a chicken and egg paradox, wouldn't it?

Second, it's all your delusion or fabrication. For the sake of serious discussion of your statements, let's leave this possibility behind.

Third, there is a possibility that you saw something I wrote in a different world line. Basically, that means that 10 years ago, you existed in a different world line than the world line we're at now. However, that explanation brings out an impossibility. When the world line changes, every cause and effect is reconstructed from past to future in order to prevent paradoxes. That theory was proven in 2036. So, essentially, it's not expected for memories of another world line to ever remain unchanged. Not even for time travelers like me... Do you have any knowledge on this point?

http://lparchive.org/SteinsGate/Update%2048/

Rintarou posted: Subject: There's something I'd like to ask

Thanks for the info about the IBN 5100. This program code is from SERN's database. Well, besides that, I've successfully made a machine that sends mails into the past, but when we change the past by sending a mail back, does that change the world line? Some of the events are undone, but does something else influence that? You said that the world exists by the many-worlds interpretation, but I want you to tell me the basis of that.

[…]

John Titor posted:

Subject: Details

Greetings, Kyouma. I want to verify whether or not what you wrote in your mail is true, so can you tell me the details of what you changed in the past?

Rintarou posted:

Subject: Re: Details

We sent a mail today. It was sent 170 hours prior, that is, Tuesday of last week. Its contents were the third class prize winning numbers for the Loto6 chosen on Tuesday of last week. Right after we sent the mail, everything in my surroundings concerning that subject was instantly deleted, including my partners' memories about even having sent the mail into the past. The mail we sent into the past also disappeared from my cellphone's sent history. The mail certainly was sent back 170 hours, as not I, but my friend got a Loto 6 ticket. It was slightly off, though, since one of the numbers was wrong.

John Titor posted:

Subject: Very interesting

That's very, very interesting. Just judging by the phenomenon you described, I would say what you accomplished is indeed changing the past. I suspect that the mail you sent into the past changed the world line's divergence, if just a little. BRAVO! The instant your mail arrived in the past, I think you were moved from your original world line to an ever-so-slightly different one. In this world line, the world's supposed past became this: You learned the Loto6 winning numbers from a mail you got from your future self, told your friend the numbers, and your friend mistook a number upon buying the ticket. So the mail probably disappeared from your sent history when the world line changed. The only point I don't get is why you still have memories from before the past was changed. I just want to get things straight, but this is the truth, right?

Rintarou posted:

Subject: Re: Very interesting

I still have memories from before the past was changed. This is the truth. By the way, this is actually the second time this phenomenon has happened. John, did you not experience something like this when you time traveled back 26 years? Or do you think its occurrence is somehow influenced by how the world line changed by my individual will?

John Titor posted:

Subject: Memory

I've confirmed that the current divergence value is 0.571015%. I cannot tell what the value was before you changed the past. The reason is because I, like your friends, have no memories of the world line before you changed the past. In the case of physical time travel, memories are conserved even if the world line changes. That's been proven by my very own experience. But in the case of that mail, the time traveler (let's just call you that for convenience's sake) changes the past without jumping through time, a situation that hasn't been hypothesized yet in 2036, where I come from. The time machine completed in 2034 is established as a system to physically jump through time and world lines. And so, I do not have the means to explain the phenomenon you are experiencing.

Rintarou posted:

Subject: Re: Memory

John, how exactly do you measure divergence values? What are those numbers based off of in the first place?

John Titor posted:

Subject: Explaining the many-worlds interpretation

Strictly speaking, it's a little misleading when I wrote that the world follows the Everett Wheeler model. More theories that were developed based off of it were popularized. In the two years following 2034, when the time machine was completed, discussion over world explanations progressed dramatically. In 2036, it was clarified that the world was constructed of things called "Attractor Fields", which describe the extent of world line convergence. This theory was originally hypothesized in 2020.

John Titor posted:

Subject: Re: Re: Memory

Sorry, I forgot to mention the divergence numbers. I have a personal meter that measures them. My original world line in 2036 was calibrated to be 0%. It is, after all, a subjective, relative measurement, not an absolute. In the end, this tool can only indicate the current divergence.

Rintarou posted:

Subject: Re: Explaining the many-worlds interpretation

Please give me more details about those Attractor Fields, and how they affect the change of world lines.

John Titor posted:

Subject: Observing convergence

Attractor Fields are, simply put, the focal points of world line divergence. They can also be used to explain things once called "fate" or "change". There is no real meaning to making small changes to the world line. Small changes result in the same conclusion due to convergence, and humans who can observe that convergence rarely exist. I haven't met anybody who holds that sort of ability, so I'm not qualified to accurately judge, but... Kyouma, you could possibly be that rare existence who holds that ability. You might be able to guide the world to the world line beyond 1% divergence. Beyond the Attractor Field wall.

Suzuha explaining about Attractor Fields and convergence to the labmems in the VN

• _
• Part 1
• Part 2

A small note: Once again the scenes in which Suzuha's whole explanation about world lines occurred in were different in the original VN and the anime.

http://lparchive.org/SteinsGate/Update%20110/

Kurisu: "So you mean you understand the structure of the world? You wrote that it can be explained with the Everett-Wheeler model or the many-worlds interpretation."

Suzuha: "That was fake. Camouflage so that SERN wouldn't target me. If I mix one lie into the truth, then the bad apple spoils the barrel."

K: "So you don't understand it, then?"

S: "I do. The world's structure was clarified in 2036. It's not the many-worlds interpretation."

K: "...Really? Tell me the details!"

Okabe: "'Attractor Fields'…"

S: "Correct. I told Okabe Rintarou directly by mail."

K: "What sort of explanation is that?"

S: "The world is made of world lines and attractor fields."

Suzuha takes a red yarn ball out of Mayuri's costume sewing set placed on the table. She holds one end of the yarn and drops the ball on the floor. She stretches out about a meter of the yarn in front of her face to show it to us.

S: "The world's structure is like twisted yarn. "Several possible worlds are superposition, always branching out infinitely. "The entirety looks like one piece, but at the micro level, the world is organized like thin intertwined threads. And at the end, those fine threads converge into one. The paths are different, but the ends are the same."

K "Isn't that determinism?"

S: "It might be close, but it's a little more rough. It sort of cherry-picks from the many-worlds interpretation and the Copenhagen interpretation."

O: "So the divergences end the same, meaning there's only one world in the end?"

S: "Exactly. And so, the bundle of world lines within the range of convergence make up an attractor field. There are also several attractor fields. This twisted yarn is Attractor Field α. In its range are α World Lines."

Suzuha indicates the yarn she's holding while cutting meter lengths of blue, yellow, and white yarn. She creates a multicolored string.

S: "Blue is Attractor Field β, yellow is γ, and white is δ. Each has several of their respective β World Lines, γ World Lines, and δ World Lines. And there are hundreds of millions of these."

She bundles them together and stretches them out again. The several multicolored yarns intertwine into one fat twisted yarn.

S: "Several attractor fields are superpositioned like this. In each attractor field, the converging result of events is different. They don't interfere. Each remains independent. There's only one if you trace it back to the origin. Attractor fields do converge at a very macro level, but that spans hundreds of years. It's best to think of them as large divergences."

Daru: "Can you compare it to an eroge? Tell me, oh erotic one."

K: "Th-There's no erotic one here."

O: "Nah, it's just like an eroge. Each heroine's route is an attractor field, and the small choices within are the individual world lines. But at the end, they all enter the true route for the grand ending."

D: "The problem is if the common route is long or short. By the way, I'd choose the little sister character's attractor field."

O: "Whatever."

K: "...These guys are no good. I need to do something quick."

S: "Umm, I don't really understand those eroge things..."

K: "You don't have to take them seriously."

Basically, the reason I can't save Mayuri no matter how much I struggle is because of the attractor field's special trait - absolute convergence to a single result? Crap... That means Mayuri really is being killed by the world...

D: "But then, isn't it impossible to change the future? It'll converge in the end, right? No matter what you do, the result is the same."

That's right. That's why Mayuri gets killed no matter how many times I leap.

S: "…We're going to escape outside the scope of this Attractor Field α we're in."

http://lparchive.org/SteinsGate/Update%20111/

O: "Outside the scope…?"

S: "Basically, we're going to leap to the β World Line in Attractor Field β."

K: "We won't get interfered with?"

S: "Attractor fields completely diverge. But if we go to the instant they diverge, then..."

K: "The instant they diverge... is that now?"

S: "I was taught that a large crossroads in Divergence exists in 2010. "An earth-shattering divergence, on par with the ones in 2000 and 1991, occurs, causing a branching on the attractor field level."

Mayuri: "Umm, why 2000 and 1991?"

S: "Global scale incidents happened on both years."

M: "Incidents?

O: "1991 was the collapse of the USSR, right? But what was in 2000...? If it were 2001, it would be the simultaneous terrorist attacks..."

S: "2000 had the Y2k problem."

D: "Haah? That wasn't as big a problem as it was hyped out to be, was it?"

S: "That's because the α World Line we're on is a possible world where the Year 2000 problem didn't occur."

So basically, does that mean there are other possible worlds where the Year 2000 problem did occur...?

S: "And 2010."

M: "Did a large event happen this year?"

S: "This year's mysterious event..."

Suzuha looks towards the development room.

S: "Can it be anything other than history's first successful time machine?"

M: "Ah, I see! That's true. Amaaazing."

K: "Another question."

Kurisu keeps plowing ahead. I guess this is one of her scientist traits.

K: "These superpositioned world lines aren't parallel worlds, are they?"

S: "No. At the very end, they're just possible worlds that exist simultaneously."

K: "Then how do you observe the differences between world lines? Isn’t that impossible without the perspective of a god?"

S: "That's usually true, but..."

Suzuha looks at me... don't tell me!

O: "Reading Steiner!?"

S: "Is that what you named it? Okabe Rintarou, you have the special ability to observe the passage of world lines, correct?"

O: "Yeah."

S: "That is the key. Your special ability is the key to release the world from the curse of SERN's rule. Right now, you are an existence rivaling God."

O: "…My ability..."

S: "Outside the scope of Attractor Field α - if you reach the β World Line... the converging result changes, too."

My body trembles. I almost roar from excitement.

O: "…Can she be saved?"

Mayuri. Can she be saved?

Suzuha nods clearly.