I've always been fascinated by the possibility of traveling backwards and forwards in time, and scientific opinion is still divided on whether or not such a thing is even theoretically possible. Noted physicist Stephen Hawking seems to believe in the possibility of time-travel, but only forward, no backward time travel according to his work on black-holes and cosmological constructs. The worlds that art, literature and science inhabit are joined together by imagination, multiple dimensions and endless possibilities.

"Chronology protection conjecture" is an answer to the potential time causality problems produced by time travel. (Access Credo Reference with your library card.)

In 1916, German astronomer, Karl Schwarzschild used the field equations to calculate gravitational effect of a spherical body, such as a star. If the mass could be extremely dense, then a highly concentrated singularity could form, the gravity would be so strong, anything pulled into it would never be able to escape. This highly dense gravity mass would be the center of a severe time distortion, light would never leave or escape its gravity, and thus the concept of a black-hole was born, out of Einstein's theory of general relativity.

Yet It took writer and poet Edgar Allan Poe to pen his poem, "Eureka" in 1848 where he correctly speculates that the star light we see from earth in an infinite and expanding universe, will take time to travel, thus when we peer into the evening skies, in many ways we are seeing old light, born light years ago, only reaching our grasping minds and eager eyes in our present time, 2013. Since the rise of sentient modern hominids, believed to have originated in East Africa some 200,000 years ago, there probably has always been some form of regret, guilt, maybe a fleeting memory of a familiar place we want to return, but just can't make it there. Perhaps primitive Neanderthals even felt a twinge of existential angst, though what that might look and feel like is anyone's guess.

Some of the first cave drawings were found in the Apollo 11 cave in southern Namibia (named because they were discovered in July 1969 when the spacecraft landed on the moon.) These drawings have been dated 26,500–24,300 B.C.E., making them as old or older than the Paleolithic cave paintings of Western Europe. Humankind creates art, science and culture in order to attempt to preserve, maintain, build, honor, relive and shape our past, present and future.

The cyclical flow of time is sometimes symbolized by the Uroboros, the snake wrapped in a circle bringing its tail to its mouth. Another manifestation is the circular-shaped calendar, of which the Chinese version is among the most widely recognized. Current cyclical measurements of time include not only how we still use the earth's motions for recognition of the passing of days and years, but also how we divide these measurements into smaller portions. We repetitively use the same names for labeling the 12 months of the year, and use the same number of hours in a day, minutes in an hour, and seconds in a minute.

One only needs to think of "daylight savings" time and the advent of the Julian Calendar to understand how our accounting of time's passing is not only a cultural phenomena, there's a psychological component as well. Indeed, one popular belief about the origins of April Fool's day is believed to have started around the slow acceptance of those who initially refused to accept the Gregorian Calendar, which changed New Year's from April 1, to January 1.

Whenever I read or think about time-travel, there seems to be some broad categories and types of time-travel, in both literature and science. First, there's the general acceptance that time-travel is a "natural phenomena." Time-travel in fiction can be the result of a physical affliction, geo-spatial phenomena, drugs or the result of fickle chaotic happenstance, often solely depending upon one's point of view. Often no complex machine is required, just a time portal like-bubble in the back of the diner. In the Stephen King novel 11/22/63, a time traveler attempts to prevent the assassination of President Kennedy, which occurred on November 22, 1963. We all know that diners are the best places for time travel, don't we? But heck, we can build a time-machine if need be, just look to H. G. Wells, who coined the term in his 1895 first extended work of fiction, The Time Machine (e-book).

"Billy Pilgrim has become unstuck in time," as Kurt Vonnegut penned, or in the case of The Time Traveler's Wife by­ Audrey Niffenegger, the mechanism by which time is traveled is revealed to be known as Chrono-Impairment. A condition which is beyond the protagonist's control, so perhaps we all really just end-up becoming unstuck in time, but that's another post...

In physics there's natural and common occurrences, or sometimes not so common lab "enhancements, under certain circumstances, maybe a particle accelerator, or an interstellar wormhole, through a mulit-layered dimension, in an undiscovered or unrevealed universe, time travel has/will/can't happen. Maybe time-vistors walk amongst us, but we just don't know about it.

The natural-unnatural phenomena can be something akin to Mark Twain's "A Connecticut Yankee in King Arthur's Court," or Ambrose Bierce's short story, "The Difficulty of Crossing a Field." In other words, something quite out of the ordinary happens, no real explanation is given, the gist of the story picks-up after the unusual event. In Bierce's case life intersects fiction, when the writer vanishes on a route to Mexico. In one of the last known letters Bierce posts to a friend, "As to me, I leave here tomorrow for an unknown destination," subsequently Bierce then becomes a character in fiction when his disappearance fictionalized in the novel by Carlos Fuente's "The Old Gringo." In Twain's story, a hit on the head transports Twain's protagonist, Hank Morgan to King Arthur's Court. Incidentally, Twain accurately predicted his death would be at the time that Haley's Comet orbited the earth, once every seventy-five years.

"I came in with Halley's comet in 1835. It is coming again next year, and I expect to go out with it. It will be the greatest disappointment of my life if I don't go out with Halley's comet. The Almighty has said, no doubt: 'Now here are these two unaccountable freaks; they came in together, they must go out together.'"

In Ambrose Bierce's story, Mr. Williamson encounters an unnatural event while walking across vacant field. He simply vanishes. His occasional disembodied voice still heard wailing for help to his grief-stricken helpless wife, who eventually goes mad over the mystery of his disappearance. So ok, maybe he didn't travel in time, but vanishing or teleportation is a good indication of time-travel.

In Eric Bress' and J. Mackye Gruber's, Butterfly Effect, Ashton Kutcher's Evan is able transport himself into time, but that notebook seems like an important tool. "Note-to-self, carrying a cool notebook, will not guarantee time travel, but it certainly can't hurt."

Speaking of hurt, not all time travel has to hurt, sometimes it can get you laughs, like Peggy Sue Got Married, Back to the Future, Hot Tub Time Machine, Safety Not Guaranteed,  Happy Accidents and, About Time.

One of the best works I've read on the subject can be found on Project Muse: Time Travel: A Writer's Guide To The Real Science Of Plausible Time Travel by Paul J. Nahin. Project Muse is available from home with a valid library card and onsite at NYPL.

I've come to the conclusion that time travel is possible, and not just forward.

Bring your library card and don't forget your imagination... Time sure can fly at the library!

If you don't like the future you see, build one in its place, and if you don't see a title in our catalog, please suggest it.