Friday, January 1, 2016

In with a Flash

'When I was your age, I always did it for half-an-hour a day. Why, sometimes I've believed as many as six impossible things before breakfast.' - Lewis Carroll, Through the Looking Glass
In that spirit, I thought I'd dwell upon an impossibility to bring in the new year: Faster-Than-Light travel.

Now, I know nothing about the physics of FTL travel, about the increasing amounts of resistance that accrues, even with the vacuum of space, but what interests me is the ability of the human body to cope. You see, to move at the speed of light would be to move at 3x10^8 meters each second. That's 300 000 km or roughly 186 500 miles. The human eye is able to see objects up to a distance of 3 km with good resolution, according to LiveScience and at a pulsatile frequency of 0.044 seconds, according to Stanford (Sorry, this is all quick research and figuring - nothing empirically substantive). So, the first problem is that anything seen at light speed will already be collided with in 0.00001 seconds and repeat stimuli or changes in stimuli may only be processed over a distance of 13 000 km.

The next question, then, is whether the eye can process and the body can react, by reflex or conscious action within that time frame. According to Stanford, a stimulus can produce a response in as little as 0.05 seconds. At light speed, then, what a human sees is actually 15 997 km behind him or her.

And with that, I'm afraid that humans will not be able to successfully attempt FTL travel without some kind of artificial assistance.

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Post Script:

I was doing some additional thinking: Literally traveling faster than the speed of light isn't the only means of FTL travel. There are a couple other ways of theoretical, Sci-Fi travel that have a net displacement greater than lightspeed, but whose actual movement speed relative to space is not as fast.

"Warp" speed. To my mind, given the name, warp speed gets it speed more from the manipulation of space itself, not for the velocity of the traveling object. To picture how warp would work, lay a towel out flat and run your finger from one end to the other. Now, fold the towel like an accordion and run your finger at the same speed from the same start to the same finish. Your finger is traveling at the same speed, but the overall travel time is faster. Now, what would "warping" look like in a space travel concept? I kinda visualise it as a series of regular, consecutive microjumps, ranging in size from multiple kilometres per kilometre to 1 mm/mm or smaller. Obviously, the larger jumps are faster for gross travel, but, to my mind, they would be less smooth and more difficult to maneuvre.

Wormholes. Arguably even more theoretical than warp speed, wormhole theory, in essence, seeks to create a direct "tunnel" from one point in space to another. Think of it as a larger, more stable cousin of the microjumps described above. The benefit of a wormhole is that it, in theory, could be created in any place of any size, allowing for mass transport even of terrestrial vehicles.

So, technologically, wormholes would be more likely to be the first of the two methods to be devised in real life, though the initial wormholes are unlikely, in my mind, to be stable for long periods of time or even of a very large size. From this initial base, we could see either warp or wormhole technology develop, depending on whether we figure out how to make a stable wormhole to an unknown co-ordinate or set distance away, how large the wormhole/warp apparatus would need to be, and how much energy would be required.

The last, I think, would be the biggest limiting factor. For both warp and wormhole technologies, we would need to force space to work and exist in a manner contrary to normal. This would that mean that the diameter, length, and duration of a wormhole would be in some manner directly proportional to energy cost, as resistance by space would increase proportionally and probably exponentially (hence warp technology as a usable theory between the discovery of the creation of wormholes and the development of stable, long-distance wormholes).

Now, all this being said, my knowledge of astrophysics rests at a very basic level. I only read half of A Brief History of Time when I was in high school, so there are many developments I am unaware of as well as nuances to astrophysics and space-time theory that are beyond my grasp. Nevertheless it is a fun fantasy to indulge and is worth pondering even for a momentary contribution to the society of the future.