(Originally written March 24, 2010)
Nostalgia is defined in the Merriam-Webster dictionary as "a wistful or excessively sentimental yearning for return to or of some past period or irrecoverable condition." I think it's interesting that nothing of "happiness" is mentioned, although I think in most cases it would naturally apply. I find myself, however, with this certain longing for almost any given point of my past. Of course, the best-remembered times are the ones I have most nostalgia for. Yet there are certainly time periods that I know were rather unpleasant and I long for them anyway. There must be reasons for this so that it makes sense. For instance, I know for a fact that I was unhappy during my 7th and 8th grade years. Possibly more unhappy than I've ever been, save for one other time. We moved for the third time in three years before my 7th grade year, and I was lucky to recognize one person at the school. I was horrendously shy and awkward, and at home I didn't really do much except play video games, read, and write. Thank goodness my siblings and I have always been close (save for a few brief issues). Yet when I think back to this time period there is an undeniable longing for it. Of course, a significant part of this must be for the memory of my dad, regardless of how unhappy everything else seemed. But still… I have always been able to see him since, however rarely, and I was not blind to the "problems" at home. There must be more.
The other obvious low-point I hinted at was immediately following our final move, away from Cheyenne and the wonderful friends that helped to finally peel the thick, broken shell from my insecure, timid self. I still shudder at the thought of where I'd be now if things had happened differently. And the ones most immediately responsible surely know who they are. So my family moved, and there was no sign that things would have otherwise changed in the foreseeable future. It tore me up. I was terrified of the thought that I might never make such friends again. In some ways, of course, I was right, but I managed to hold on to enough confidence to make a feeble attempt once school started here in Belton. And thankfully it did not take long at all. Otherwise I'd have been in deep trouble. The point is, I even have a certain longing for this time. This summer, the summer of 2004, whose memory I swore I'd curse for all time, I can't help but… miss. This is a pitifully feeble longing compared to the rest, mind you, but it's there.
Almost as far back as I can remember I lived in a situation which, upon reflection now, I would not be totally against somehow returning to. I do not seem to have this sense of nostalgia for my very early life, however. I have quite a few memories of the ages of three and four, and I certainly have no yearning for them back. The emotion seems to kick in around, roughly, the age of ten. I think this must be a result of the developing personality and perceptions of the world which provide a powerful, deeper sense of our views of the past, possibly even more powerful than the specific good experiences themselves.
Unless I am an anomaly, it seems we are in a sense wired for this yearning of the past. Perhaps this is due to a comfort we find in what is familiar to us. Obviously the past is familiar, simply because we remember living it. Maybe this subconsciously seems like an easier, safer life for us. Certainly at the time, especially for me during my junior high years, they were neither comfortable nor easy. But looking back today I would know exactly what to expect and, as evidenced by my life today, I made it out alright. So there is a sense of security in the past which we can't really get from the present, and especially not from the future. Is this a driving force behind this "nostalgia?"
This isn't to say that the more positively regarded past isn't responsible for nostalgia, or that it's equally responsible. It is most definitely to blame for the much more powerful nostalgic urges. I still have reminiscences of my last years in Cheyenne (2002-2004) that brings my emotional mind to its knees. Into a puddle of tears. It is by far the most extreme longing of all. I'd rip a wormhole with my bare hands in the space/time continuum right here in front of me now if I had the means to navigate myself properly through it.
I'd rather say instead, therefore, that nostalgia is "an excessively sentimental yearning for times past not necessarily because they were so great, but simply because they are gone."
The sun is about 390 times farther from the earth than the moon is, and its diameter is about 400 times as large as the moon's, and this ratio is what makes a solar eclipse possible. They appear almost the same size in the sky, and on those occasional meetings, the moon can completely block the sunlight. This beautiful occurrence (which I'd love to actually witness) is due to a pretty extreme "coincidence." If the earth were somewhat farther away from the sun, or closer to it, the ratio would be different. Similarly, if the moon were slightly larger or smaller, or closer or farther, the ratio would be different. If the sun were either smaller or larger, the ratio would be different. In any of these cases an eclipse would be much less interesting, because if the moon appeared much larger it would easily block everything, including the corona, and if the moon appeared much smaller it would only ever block a lame portion of the center of the sun. Still cool, but much less so.
This near-perfect set of coincidences boggles my mind. It could have been so many other ways. Some planets, like Venus, have no moons. Some planets, like Mars, have tiny moons which could never hope to rival the sun. But ours is large enough, and situated just right, to provide us this feast for the eyes. Of course, a coincidence (even one so mighty as this) may be just a coincidence--there's no way to tell, in this case, but I like to wonder whether this is a neat little perk incorporated into an intelligently designed Universe.
There is an interesting theory in physics called the many-worlds interpretation, which (to summarize rather simply) views reality as analogous to a many-branched tree where every possible outcome is realized. This is supposed to resolve all possible paradoxes, especially those concerning time travel, because there is supposedly an infinite number of universes--one for every possible outcome of every single event in history. So for every time you swallowed a blue pill instead of a red pill, there is an alternate universe where you actually swallowed the red pill. And every time you activate your time machine you are creating a new universe and are free to kill your grandfather without worrying about impossibilities. I guess, in a way, it just seems to come across as "too easy" a solution to all of these problems. Which doesn't prove its invalidity, sure, but to me casts serious doubt.
This theory has a major flaw, however, as I see it, simply because by definition it is utterly impossible to verify. If there is an alternate universe where I woke up this morning ten minutes later than I did in this one, when is that ever going to matter? Can it ever have any relevance whatsoever? So arguably, only if a way to tap into some kind of energy source or… something between them is ever discovered will this actually be of any significance. But it's an interesting thought, at least.
Time travel, by the way, is such a headache. When considering the grandfather's paradox (that is, traveling back in time and somehow preventing your grandfather from ever meeting your grandmother) the only logical conclusion that seems acceptable to me is that it's simply impossible to travel back in time. However, there is another theory I've come across called the Novikov self-consistency principle, which claims that "the only possible timelines are those which are entirely self-consistent, so that anything a time traveler does in the past must have been part of history all along." I imagine a peaceful scene, 100 million years in the past, with a group of dinosaurs calmly drinking from a stream. As I activate my time machine I suddenly emerge into existence in front of them, hurl a stick at the closest one, and then vanish back to my own time. I didn't change history because 100 million years ago on this single timeline I appeared out of nowhere, for whatever length of time I spent time traveling, and then vanished. Here in the present I disappeared for this same length of time, then returned. But an unchangeable past seems to deny the notion of free-will. So, again, it seems an unacceptable solution.
And the list goes on. Time travel is clearly a deeply considered idea. I've tried to look into the matter as far as I can with any easily accessible means, and while none of these theories can be undeniably disproven (or proven) at this point, they all seem pretty far-fetched from an intuitive sense.
Time travel into the future, however, (if you would call it that) clearly seems to be possible. From my understanding, time slows down relative to a quickly traveling object. As an object approaches the speed of light, its flow of time is likewise reduced. I once read this described in a very nice, simple way: we are moving through both space and time, simultaneously. But our "combined" speed through both is a sum of each, and they must keep the same ratio. So imagine a quadrant on a graph, with an x and y axis. The x axis is movement through time, and the y axis is movement through space. Anybody on Earth is traveling at, on a meaningful scale, next to no speed. So time is flowing at practically 100%. As an object (such as a spacecraft) gains velocity, it is moving faster through space and likewise slower through time. The implications of this are that if an object actually reached the speed of light, its relative flow of time would stop completely. And if this object's velocity surpassed the speed of light, its relative flow of time would reverse. The problem with this is that the energy required to accelerate an object of any mass to the speed of light is infinite, thus impossible. By any known means...
So if I stepped into a powerful spaceship and flew to the nearest star (4.2 light years away) and back, less time would have elapsed for me than for everyone else here on Earth (the precise details would depend on exactly how fast I was traveling at every point of the trip). I've come across and enjoy the term "time debt." So I may step out of the spaceship a mere one year older than when I had left, yet everyone who remained stationary here on Earth could be, say, twenty years older. But this is a wildly impractical method of "time travel" even if it is has been verified by all experiments. Very, very intriguing, though.
There are as many possibilities for the existence, location, definition, behavior, etc. of extraterrestrial life as our minds are capable of fantasizing. But there is a critical flaw in such runaway dreams. As far as has been made known to the public (choice of words to appease any Roswell "fans"), no extraterrestrial contact has ever been made. There has not even been strong evidence that any life whatsoever has ever existed outside Earth. Despite the profound disappointment this causes me, I'm glad the scientists are remaining skeptical. This is very, very important. If the claim is ever made, it needs to be beyond all doubt. Like in Independence Day.
"The apparent size and age of the universe suggest that many technologically advanced extraterrestrial civilizations ought to exist. However, this hypothesis seems inconsistent with the lack of observational evidence to support it." There is a term for this flaw in logic--the Fermi paradox.
There are many proposed reasons why this apparent fact may be true, some much more depressing (and some much more frightening) than others. There are a few that seem most reasonable to me. Any combination of these following propositions could explain the lack of extraterrestrial contact:
--No other civilizations have arisen. This is, simply, the proposal that life on Earth is utterly alone in the universe, and obviously is never going to encounter any other form of life. Very tragic, indeed.
--It is the nature of intelligent life to destroy itself. Perhaps it is an inevitable consequence of intelligent life to destroy itself either before or shortly following its rise to technological "superiority." Not an encouraging thought…
--It is the nature of intelligent life to destroy others. Yikes. We may not have had any contact with another race because, if we had, they would have obliterated us. If so, stay away, please.
--It is the nature of intelligent life to remain silent. Any civilization of significant intelligence may naturally choose not to make their presence known (perhaps to avoid some of the JERKS?). This is depressing because it means they could be around, anywhere, but this fact will never be made known. Which isn't much different to us than not existing in the first place, eh? Just come talk to us!!
--Communication is impossible due to problems of scale. What if there are any number of intelligent civilizations out there, but none of them happen to be within 200 light years from us? Or 1,000? It would take a ridiculous amount of time for any kind of communication to take place. 400 years for a round trip of light, and an unfathomable amount of time for physical travel by any conventional means. It's depressing, but at least accounts for their isolated existence. This seems to be one of the most likely scenarios to me. Everything beyond our solar system is just too far away.
--It is too expensive to spread physically throughout the galaxy. We've only been to our moon a small number of times, and it was wildly expensive (and dangerous). Unless some fundamental breakthrough occurs in the science of space travel, it doesn't seem at all likely that we'll ever have the ability to travel outside our own solar system. Our fastest spacecraft is taking 9 years to reach Pluto, and it cost like $650 million. And that was just a measuring instrument. No people to support. Going to Alpha Centauri, even by extremely generous estimates, would take 20,000 years and a godforsaken amount of money to implement. This is the other scenario that seems most reasonable to me. It may just be too difficult. Ugh. The disappointment this brings is not lessened by the thought that this means that, not only is it inconceivable, but it probably never will be any other way.
But I will never stop hoping and dreaming of the day we finally find something, or are found. Let's just hope any extraterrestrials advanced enough to contact us are fully capable of accepting our coexistence and are much further along in their "moral evolution" than we humans seem to be.
(Originally written March 24, 2010)