October 21st, 2015. We're back to the future

​Thirty years after the release of the film “Back to the future“, we finally reach October, 21st, 2015. This is the day when Marty McFly, with Doc. Emmet Brown, come to visit from the year 1985. Most of us have been waiting for this day, and have wondered how similar the real 2015 will be with respect to the 2015 in the movie. Now we can compare.

It is highly surprising how science fiction writers, from the great H.G.Wells or Jules Verne, to Isaac Asimov, Arthur C. Clarke, or Philip K. Dick, didn’t predict the rise of the telecommunications and the smart devices that rule our daily lives. Many sci-fi books talk about flying cars, colonies in Mars, which needs a push in controlling high quantities of energy on demand . This is not here yet, and energy is one of the most important problem that our society faces, so it will not be here for a while.
In the movie Back to the future II, we see traffic jams in flying motorways, but we also see hoover-boards. This fun transportation media for the young ones could be closer than flying cars, although not yet, and with some restrictions. It is not new to see in some laboratories that do research with superconducting materials, some sort of levitating toy train. This is based in the magnetic properties of superconducting materials. These materials can reject the magnetic field to enter in them, creating an effective repulsion that can make them levitate. Unluckily, up to date, we only know materials that have these properties at very low temperatures (~200C below zero). Also, in case of having one hoover-board today, we would need it to operate at those very cold temperatures, and it should work over magnets.
Another cool idea showed in the movie is the highly precision of the weather forecast, which can predict the end of a storm at the level of seconds. We have to know that weather forecast has made a huge improvement with respect to the twentieth century. Nowadays, mathematical models and powerful computers are great tools to provide us with good predictions. We can know with low error margin the weather of the next two to three days, and with reasonable accuracy the weather of the next week. But that level of precision is not going to be in our hands for many years. The knowledge of the initial conditions to do that is beyond our reach, and maybe it wouldn’t really be that useful. Even though we could know with high accuracy the position and velocity of all the molecules in the atmosphere, chaos theory predict that small variations in that information could lead to very different results after a time, and the computational effort would increase exponentially.

On the other side, they show video-conferences, tactile keys, devices that responds to the voice,  some short of smart phone that Doc. uses, smart glasses too, and tactile money. There are already among us: Skype, Google glass, i-phone, ... Even the drone that takes the dog for a walk is not far from been used, or at least we have the technology.
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Maybe the key element of these movies is the time leap that they take to travel through time. Time travel is allowed by the laws of physics. Indeed, we are currently time traveling to the future at a speed of one second per second. Well, this might not sound thrilling but Einstein’s theory of relativity also tells us how to time-travel to the future faster. To do it we only need a very fast ship. This theory predicts that the faster we move in space, the slower time elapses for us. This way, the faster we travel in space, the faster time will fly, and Marty could travel from 1985 to 2015 in a few hours. But the way he would do it is not by a leap as we see in the movie, but ti would be continuous. For example, having a spaceship that travel through space at relativistic speeds (near 300,000km/s) would make Marty experience a few hours while for the whole Earth time moves 30 years.

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