The Time-Lines in
Below is a diagram of the different time-lines that exist throughout the BttF trilogy:
The letters to the left of the time-lines represent the realities of the four critical time periods in Back to the Future. When one of these critical time periods is altered, it will create a new time-line and a new reality for that time period and, thus, be given a new letter. The time periods in the past will be unaffected by these changes, but any time periods ahead of the altered reality will also be given a new letter because the alterations in the previous time period will have rippled into the future.
As indicated, a solid line blue line represent a determined time-line. From this point in the space-time continuum, any line that is solid blue is completely determined and can only be altered by time travel. A light-blue dashed line indicates that the time-line is in flux, meaning that the future is unknown and is constantly changing depending on the actions of the time traveler who is in the past.
Below is a list of the different realities and to the right, the events which spawned them:
|
1885 |
1955 |
1985 |
2015 |
Events |
|
A |
A |
A |
A |
Marty does not time travel |
|
A |
B |
B |
B |
Marty travels to 1955B |
|
A |
B |
C |
C |
Marty returns to 1985C and recognizes changes |
|
A |
B |
C |
D |
Doc travels to 2015D |
|
A |
B |
D |
E |
Doc returns to 1985D to get Marty and Jen |
|
A |
B |
D |
E |
Marty and Doc arrive in 2015F and prevent future family tragedy |
|
A |
C |
E |
F |
Old Biff steals time machine and travels to 1955C to give his past self almanac |
|
A |
C |
E |
F |
Old Biff returns to 2015F. Marty and Doc leave 2015F. |
|
A |
C |
F |
G |
Marty and Doc return to 1985F, and recognize changes. MartyA questions Biff and discovers the truth. |
|
A |
D |
G |
H |
Marty and Doc travel to 1955D and Marty burns the almanac |
|
B |
E |
H |
I |
Doc is sent back to 1885B - Marty gets 1955E Doc’s help to get DeLorean. They discover Doc’s grave. |
|
C |
F |
I |
J |
Marty travels back to 1885C to save Doc. Succeeds and also prevents his own death. |
|
C |
F |
J |
K |
Marty returns to the 1985J without Doc. |
And yet another chart for further clarification:
|
1885 |
1955 |
1985 |
2015 |
|
A (No Time travelers) |
A (No Time travelers) |
A (No Time travelers) |
A (No Time travelers) |
|
A (No Time travelers) |
B (Marty travels to 1955) |
B (resulted from 1955B) |
B (resulted from 1955B) |
|
A (No Time travelers) |
B (Marty travels to 1955) |
C (Marty returns to 1985 early) |
C (resulted from 1985C) |
|
A (No Time travelers) |
B (Marty travels to 1955) |
C (Marty returns to 1985 early) |
D (Doc travels to 2015) |
|
A (No Time travelers) |
B (Marty travels to 1955) |
D (Doc returns to 1985 to get Marty and Jen) |
E (resulted from 1985D) |
|
A (No Time travelers) |
B (Marty travels to 1955) |
D (Doc returns to 1985 to get Marty and Jen) |
E (Marty and Doc travel to 2015) |
|
A (No Time travelers) |
C (Old Biff travels to 1955) |
E (resulted from 1955C) |
F (resulted from 1955C) |
|
A (No Time travelers) |
C (Old Biff travels to 1955) |
E (resulted from 1955C) |
F (Old Biff returns to 2015) |
|
A (No Time travelers) |
C (Old Biff travels to 1955) |
F (Marty and Doc return to 1985) |
G (resulted from 1985F) |
|
A (No Time travelers) |
D (Marty and Doc travel to 1955 and burn the almanac) |
G (resulted from 1955D) |
H (resulted from 1955D) |
|
B (Doc is sent back to 1885) |
E (resulted from 1885B) |
H (resulted from 1885B) |
I (resulted from 1885B) |
|
C (Marty travels back to 1885) |
F (resulted from 1885C) |
I (resulted from 1885C) |
J (resulted from 1885C) |
|
C (Marty travels back to 1885) |
F (resulted from 1885C) |
J (Marty returns to 1885 and chooses not to race with Needles - Doc returns to wish Marty well) |
K (resulted from 1985J) |
The events bold and italicized indicate that
these events are what spawned a change in the reality.
It should also be noted that each event from the previous time-line will have to take place in almost the same fashion in the new time-line to prevent a paradox. This is indicated in the chart below:
|
1885 |
1955 |
1985 |
2015 |
EVENTS |
|
A |
A |
A |
A |
*No time travelers |
|
A |
B |
B |
B |
*Marty travels to 1955B |
|
A |
B |
C |
C |
Marty travels to 1955B |
|
A |
B |
C |
D |
Marty travels to 1955B |
|
A |
B |
D |
E |
Marty travels to 1955B |
|
A |
C |
E |
F |
Marty travels to 1955C |
|
A |
C |
F |
G |
Marty travels to 1955C |
|
A |
D |
G |
H |
Marty travels to 1955D |
|
B |
E |
H |
I |
Marty travels to 1955E |
|
C |
F |
I |
J |
Marty travels to 1955F |
|
C |
F |
J |
K |
Marty travels to 1955F |
Once again, the events which spawned the change in the time-line are indicated in bold and italics. In the final version of the time-line, (time-line CFJK) all of the events from the previous time-lines have occurred in the altered realities. This is not indicated on the first diagram because it becomes too complicated and difficult to follow.
It appears that there were a total of eleven different time-lines created throughout the Back to the Future trilogy, 2015 having the most changes (the only point in the time-line to have an altered reality in all eleven time-lines).