In other words, not all actions that change history will completely change the timeline, only some key events will lead to great changes in the world horizon (such as the publication of the first D-MAIL and the publication of doctoral thesis on the time machine). There is also a change, that is, individual changes, but the overall world line is still changing in one direction (male to female). There is only one thing that distinguishes the key world line in the whole article, and that is whether the time machine was invented.

In the 23rd episode, Yu Ling didn't say "to stop the war is to save Li Hong's habitat", but the original words should be "the way to avoid World War III is to save Li Hong's habitat". In other words, the landlord reversed the meaning, and the original intention was to stop the world war while saving Li Hong's habitat, not to stop the war. This may be related to the translation of egg pain that the landlord saw.

Mayumi's death is unavoidable as Hong Liqi;

It turns out that the first D-MAIL was sent by accident, and the world line moved to the alpha line. This key point is that time and opportunity were invented because of this event, and another key point that this key point leads to is that truth will inevitably die of fierce truth. So, why is this inevitable? That's because as long as we don't change the point of inventing the time machine (leading β to α), it will inevitably lead to the death of Makoto Beauty. So first of all, eliminate all D-mails, that is, skip the key point of Mayumi's death, avoid the key point of inventing the time machine, avoid Mayumi's death and return to the original world line β. Moreover, Mayumi's death happened at that time, that is, the whole process happened in front of the fierce truth, which is inevitable.

Hong Liqi's situation is different. His death on the original world line is not the point. The key is whether her paper on the time machine will be published. The fierce truth can't change the fact that I had to see Li Hong lying in a pool of blood in the past, because only in this way can the condition of "canceling the unintentional D-MAIL that caused the change of the world line" from the Alpha world line to the Beta world line continue to take effect, that is, the world line will not be changed again to the Alpha line. If we can't see the scene where Hong Liqi fell, the past fierce behavior will change and may change the world line again. Fortunately, it is precisely because the past fierce really only saw "Hong Liqi fell in a pool of blood", but in fact the death was not determined. This is an established process, so the way to keep the world line unchanged and let Hong Liqi continue to live was born under such extremely complicated conditions. Whether the paper as the key point continues to exist is changed by an unimportant point, that is, the material of Wupa, which changes the future.

Correct logic line (key point):

The first D-MAIL exists (Meng Zhen depends on Li Hong's life and death)-the time machine must have been born because of Meng Zhen-Mayumi must have died because of Meng Zhen-the dystopia of the rebels and SERN.

Cancel the first D-mail-the existence of paper-the time machine was born because of Hong Liqi-the fierce man and the world war

Cancel the first D-mail-the paper does not exist-the time machine will not be born because of Hong Liqi-the unknown future

The above are the key points and corresponding chain results. One thing is clear, the time machine can't be born, otherwise someone will definitely die. Born of murder, Mayumi died; Born because of Hongli, Hongli died. The fierce truth leads to the alpha world line, and the red plum habitat leads to the beta world line.

The first purpose is to return from the alpha line to the beta line; The second purpose is to save Hongliqi and change the future within the beta line. Using a time machine to stop the birth of a time machine is basically what it means.