Flux Capacitors are so overrated

The concept of time has fascinated mankind for a long… time. Our lives are focused on its flow: when to grow food, when to sleep, when to mate, when to bundle up. We reminisce and anticipate. The flow of time is not only part of our lives, it is our lives, and our deaths, and everything in between. This all-encompassing feel to time is what makes it remarkable. Yet, until the turn of the century (excluding big thinkers like H.G. Wells) time was realistically seen as an immovable force that could never be manipulated or changed. It was Albert Einstein himself who put an end to that notion when he published his Theories of Relativity.

Now, though this blog does not have the time to go into his thought process in detail*, Einstein’s basic message was that the three dimensions of space, as well as the singular dimension of time, were not separate entities, but rather woven into one another, creating what we now call: ‘space-time’. 

Stay with me, now. 

The fact that these dimensions were all one entity meant that when space was affected, time was affected as well. Moreover, the faster an object traveled, the slower time flowed in its frame of reference. This is where the ‘relativity’ part of Einstein’s relativity theory comes in; time, in addition to space, is always relative to the observer’s position and speed. Einstein also proved that no matter how hard something tried, it could never go faster than the speed of light. This was a big departure from Newtonian mechanics, which didn’t provide a limit on the speed one traveled. 

Fast-forward to today**. Now that Einstein has shown that time is not forever constant, physicists are able to experiment with relativity in really neat ways, like, say, going into the future. Even getting up to a fraction of the speed of light can change the flow of time dramatically; The difference between my time flow when I’m going close to the speed of light and what someone else feels at near 0% light speed is called the Lorentz factor. 

The [1] at the end of the graph is the speed of light. The faster you get,
the greater the time warp. 

If the Lorentz factor is high enough (that is, if I’m going fast enough) time slows down. Once my speed drops, I find that compared to everyone else’s clock, I’ve been somewhat suspended in time. Thus, I have successfully traveled into the future. 

Going into the past is a bit more tricky. If, through sheer speed, I made time go so slow that it started moving backwards, I would theoretically be going faster than the speed of light. As Einstein showed us, this just cannot be. The faster I go, the more my mass resists; by the time I'm 99.99% close to reaching light speed, I would be an infinitely-massive object. However, physicists don't like it when things are impossible. So, they've come up with a couple of theories to get around the universe's can't-do attitude:

Wormholes

The way wormholes work is pretty easy to conceptualize, but that doesn’t mean they’re easy to find. Picture, if you will, a bed sheet. When something heavy is put on this sheet, the sheet bends to accommodate the weight; the same thing happens to space-time when something massive moves through it, like a planet or star. Now flip the sheet in half, and put two heavy things on opposite sides of the fabric. In space-time, these opposing masses would both dip down until the pockets of space-time they created touch and merge into a portal:

Theoretically, having a link between two pieces of space-time could get you back into a point in the past. However, even theoretical wormholes are only open for the briefest of moments, and controlling where you landed when you went through is next to impossible. Hmm... on to more theories!

White Holes

If black holes are the vacuums of the universe, white holes would be the power washers. They are defined as the other end of a unique type of black hole, one that has enough centrifugal force in its center to create a safe gravity passage through the middle; without this spinning motion, anything going into the black hole would end up crushed, having no chance of escape. This centrifugal force could only come from incredibly dense matter, such as an unbelievably massive star or a cluster of neutron stars, spinning in perfect time. This means that, instead of a singular point of mass in the middle, there’s more of a pipe shape going through and out the other side of the black hole, i.e. the white hole. Going through this dense field would undoubtedly distort time, taking you back a long time ago, and possibly to a galaxy far, far away. The astronomical conditions that have to happen make this a reality are much too incredible to make this a viable system of time travel, but... hey, we can dream. 

Besides, even if one person managed to follow through with this dream and go back in time, he would violate the Law of Causality, creating an alternate timeline, or possibly annihilating him- or herself in the process. We all know what happens then...

Awesome Guitar Solos.

*Get it? Time? Not enough time? ...yeah.

**More time references! Hilarious.

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