Lately, I had been hearing a lot of buzz around the new movie Interstellar so I decided to see the movie to see what all the rave reviews were about. First of all, if you are not into sci-fi, or you really couldn't be bothered to watch movies with an overwhelming science background, then this movie is not for you. Please watch something else. If you watched Gravity, and you loved the movie, then Interstellar is another movie that explores the subject of space travel. It was brilliantly written, and the dialogues in the movie were faithful, to a great extent, to the true and current state of astrophysics and cosmology. So I'll definitely recommend it.
However, there were certain aspects of the movie that are scientifically inaccurate. I'll attempt to point out just a few instances where the movie took too much liberty with their presentation and thus presented something more akin to fantasy. Now, there is a possibility that what I am going to state here, based on what I was able to hear and understand, may not reflect what the script writers had in mind. There is also the possibility that upon watching the movie again later on, and having the benefit of understanding everything that was said, some of these faux pas may be forgiven and written off simply as a movie director's "artistic license". At any rate, for those who have seen the movie, let's examine some of the assumptions and false leaps that were found in the movie:
A) In the movie, just as you might expect, there is an exploration of the concept of a wormhole. Because of the vastness of each individual galaxy, human deep space exploration is not going to be physically possible. Light travels at an incredibly high speed—299,792,458 meters per second. As a matter of fact, nothing in this physical universe travels faster; it is the fastest speed at which matter can travel. Now, let's do some math. If light travels at 299,792,458 m/s, can you imagine the distance in miles that light might travel in a year? That's a whopping 5,878,499,817 miles. Yup, almost 6 trillion miles! That is an astounding distance. However, here's a more startling fact: our own Milky Way galaxy (one out of billions of other planets in the universe and by no means one of the biggest) is so vast that traveling at the speed of light in a year, it will take you 100,000-120,000 years! Let that sink in for a moment. Our space travel shuttles are not flying anywhere close to the speed of light. They are not even flying at up to 10% of that speed. But assuming we pretend that they are indeed blazing at the very speed of light, it is going to take a manned rocket over 100,000 years to traverse our galaxy alone! That is simply stupendous.
In the movie, the crew have to fly to a different galaxy. So, there has to be a means to achieve this on a manageable time scale. That is where the concept of a wormhole comes in. A wormhole is a hypothetical space-time bridge or tunnel. The idea was that for these space explorers to get to a different galaxy they had to pass through a wormhole which would in effect patch them through to the other side of the universe. It is necessary to point out though that wormholes are still very much speculations and have no basis in empirically verifiable science. In other words, there is absolutely no observational evidence for wormholes. I think too many times, people accept the concept of wormholes a little too easily as though they are brute facts of nature but they are not. Yes, the physics of a wormhole is neat and the equations of the theory of general relativity may hold true in hypothetical wormholes, but the larger point is still that they are useful fictions and have no empirical substantiation. It is needed to make a movie like Interstellar—they can get to the interesting parts of the universe they want to get to and not be stuck on a flight that will literally take about 100,000 years to complete (longer than the humans flying them can ever hope to live even if they had a hundred lifetimes).