Skip to main content

back to the future - Why did Doc need to use a moving car to achieve 88mph?


88mph is an important speed to screw the space-time continuum. But, motion is relative...


Hey doc, can you please explain 88mph relative to what?


What we see in the movie: it was the speedometer reading which matters. So, place the car on a conveyor belt moving in opposite direction of the car having the car's speed and acceleration. The car will reach 88mph without resultant displacement and will go time warp.


To confirm, the speedometer was normal without any modification to record absolute speed (which is impossible). You can see in the first time travel (of Einstein) that the remote-controlled car was slipping on road initially but still Doc was recording increasing speed.


This means it's clear that the time circuit needed only a revolving thing in space with a tangential speed of 88mph (w.r.t. the axel which is, at rest, relative to the time circuit). In the case of the flying car from 2015, a similar setup in rocket exhaust can be assumed (motion is relative, after all).



My question: why didn't Doc use a time machine at rest with revolving parts? It would be less risky. (Note: Marty crashed twice.) Plus... instead of pushing the car with a steam train, the revolving parts could be revolved easily with a steam engine.



Answer



One theory is that the flux capacitor generated a portal through which the De Lorean traveled, and it could only remain open for a brief moment with the power available; by Doc's calculations, the length of that moment was exactly the amount of time it took for a De Lorean to travel its own length at 88 mph (that is, to enter the portal completely). A stationary machine would be able to generate the portal, but not enter it.


Comments

Popular posts from this blog

futurama - How much time is lost in 'Time Keeps on Slippin''

In time Keeps on Slippin' , Farnsworth creates a basketball team which he matures by abusing Chronitons. This leads to time skipping forward by random, but ever increasing amounts. How much time was skipped in this way? Answer Unfortunately, I don't think a good estimate can be made for this, for two reasons: Many of the time skips move forward by an indeterminate amount of time. At one point, the Professor mentions localized regions of space skipping forward much more than others. We then see two young boys on the street below complaining about having to pay social security, only to suddenly become senior citizens and start complaining about wanting their money. Thus, each individual could have experienced a different amount of time skippage.

What is Tolkien trying to say in this letter?

In a draft of a letter, later recorded as #246, Tolkien makes a strange statement. I am interested in the first few sentences of the letter, but I will include the remainder for the sake of context. In the 'Mirror of Galadriel', 1381, it appears that Galadriel conceived of herself as capable of wielding the Ring and supplanting the Dark Lord. If so, so also were the other guardians of the Three, especially Elrond . But this is another matter. It was part of the essential deceit of the Ring to fill minds with imaginations of supreme power . But this the Great had well considered and had rejected, as is seen in Elrond's words at the Council. Galadriel's rejection of the temptation was founded upon previous thought and resolve. In any case Elrond or Galadriel would have proceeded in the policy now adopted by Sauron: they would have built up an empire with great and absolutely subservient generals and armies and engines of war, until they could challenge Sauron and destroy ...

tolkiens legendarium - Was Galadriel's temptation of Boromir instrumental to his fall?

We know Galadriel tempted the members of the Fellowship, did she tempt Boromir with visions of taking the Ring and saving Gondor? In the books, Boromir willingly accepts the judgement of the council that the Ring should be destroyed, but after the meeting with Celeborn and Galadriel his personality seems to change. Was the temptation offered by Galadriel in some way responsible for Boromir's fall? Answer It's likely, but not certain I believe it is likely Galadriel tempted him with the ring, and in doing so re-ignited a pre-existing idea to take the ring, but to be clear lets break this down into three parts. Boromir at the Council of Elrond Boromir after setting off Boromir after being tempted Boromir at the Council of Elrond Boromir pleas for the ring to go to Minas Tirith, to help Gondor in its defense against Mordor. “ Why should we not think that the Great Ring has come into our hands to serve us in the very hour of need? Wielding it the Free Lords of the Free may surely...

harry potter - What is the difference between Diffindo and Sectumsempra?

In the Harry Potter books, Diffindo is called the 'Severing Charm' and it’s most commonly used to cut ropes and the like. However, in the last book Hermione uses it on Ron but misses, creating a 'slash in his jeans' and his knee gets cut, causing him to 'roar in pain'. We've only seen Sectumsempra used once on screen when Harry directly uses it on Malfoy in the sixth book, but there it's mentioned that he is 'waving his wand wildly'. Wouldn't Diffindo, if used in such a fashion also cause a similar effect? Similarly, if it was able to cut Ron, it would also be able to, say, chop off an ear (George's)? In that case, how are these two spells different, except for Sectumsempra seemingly used exclusively to hurt humans? Answer While Diffindo and Sectumsempra both can be countered by other spells, Diffindo is far more easily countered. Reparo, a relatively common spell, can completely reverse its effect when used once. “He pulled the old cop...