BACK TO THE FUTURE!!! – A critique

As promised I wanted to look at Back to the Future from the role of a scientist. Ok, so having studied physics and knowing that many people haven’t studied physics and think it’s strange weird or difficult. However I will try to enlighten you while preventing people from cowering in the corner.

Also let me say firstly, that the Back to the Future trilogy, is probable my favourite movies of all time. So when I give this little critique it is not because I dislike the movie, but want to highlight the discrepancies we as scientists are critical of.


As I have previously discussed time travel is theoretically possible from Einstein’s theory of special relativity however it might require a little more than 1.21 Giga watts and a Deloraine (which is my life time dream to actually own) anyway in this critique let’s ignore the mode of time travel and look at some errors in time travel logic from the movie.

For those who haven’t seen the movies I would strongly encourage you to do so, not only to understand what I am talking about in this post, but because the trilogy is a classic and highly enjoyable.

Ok so let me explain how, back to the future time travel works as discussed by Dr Emmitt ‘Doc’ Brown. According to him the universe travels along one timeline, and if for some reason the time line is changed, it diverges towards a new future, while the old future is erased from existence.


When Marty first travels back in time from 1985 to 1955 he changes the circumstances of which his parents meet and he also meets 1955 Doc brown counterpart informing him about his possible future, he then travels back to 1985 where he sees the doc get shot and himself travel back to 1955. But at home, he sees that his parents are now very successful and not dysfunctional at all. How is it possible that the doc and Marty have the same relationship now even though Marty would have had a startling different upbringing combined with the fact that doc also now knew he would build a time machine in 1985? Coincidence, paradox correction or an error in time travel logic?

Back to the future 2 revolves around the Almanac from 2015 which has all sporting results from the last half of the 20th century. In the film, Old Biff steals the time machine and travels from 2015 back to 1955. Where he gives the book to his young self, this changes the timeline completely however, somehow in contrast to Docs hypothesis, he is able to travel forward to an unchanged 2015. Where Doc, Marty and Jenifer are able to return to an altered 1985. According to Doc the future they were occupying in 2015 should have disappeared when Biff received the almanac in 1955 but that didn’t occur. How was this possible?

Ok now I know that isn’t much of a rant for more ranting from a scientist/mathematician please visit this website.

The Science of Back To The Future [BTTF Week]

I wish to add that this movie was one of the sole reasons I studied physics and in general, science. Although now studying Mechanical Engineering, I hope one day to travel back to the future.

Ps. I believe I still have yet to find a comment claiming the points in regard to Einstein’s famous equation please see my previous post all you physicists out there.

For those who wish to grab the points from this post and watch a great movie I ask:

In Doc Emmitt Brown’s 1955 house which famous scientists’/inventor’s portraits are above his fireplace? (10 points for each one)

Also what are the names of Docs two dogs? One in 1955 and the other 1985(5 points each)

Hope you enjoy my post and please comment



*Please note all images are property of Universal Studios

2 Responses to “BACK TO THE FUTURE!!! – A critique”

  1. Jenny Martin says:

    Awesome post, I am also a big fan. Although I’m ashamed to say that I still haven’t managed to sit and watch all 3 in one go. I know, I’m just not trying hard enough.

    Anyway, thanks for the physicist’s angle on the movies – I must say I had never really thought about the discrepancies. It is obvious now you point it out, but I was always too busy enjoying the rest of the film. so what is your take on ’12 monkeys’ and some of the other time travel films? It’s a big genre. And without question a highly successful way of getting people to think in a scientific way.

    Oh, and I’m hoping I can claim all 50 points………..

    Einstein, Edison, Newton & Franklin
    Copernicus (’55) and Einstein (’85)

  2. Alexa says:

    Ha ha, I knew I would one day see this rant in some written form or another! I must say that now since you’ve plainly highlighted the descrepancies in time travel logic, they all really do not make sense.

    I guess the reasons why I never cared to hear about these errors is because I found it too confusing to follow the story on some sort of continum. Basically, I thought it would be too hard to follow.

    I suppose that highlights why you’re taking this class. Average, un-science-y people find it hard or don’t believe they have the ability to follow perceived complex science such as time travel. I guess the moral is to take that extra minute out to try to understan so we can effectively combat important scientific uncertainties like climate change.

    Well done 🙂