According to quantum mechanics, every atom is like a miniature solar system, with the nucleus in place of the sun and electrons in place of planets orbiting the nucleus. According to Niels Bohr, electrons revolve around the atomic nucleus along particular and fixed orbits.

   * = electrons (within orbit)
   @ = nucleus (protons & neutrons)

         /         \
        /   _____   \
       |   /     \   |
       *  |   @   *  |    A HTML representation of an atom
       |   \_____/   |    --------------------------------
        \           /

If we bombard an atom with energy we may 'excite' it's electrons to jump from one orbit to another, but they can never be made to reside somewhere in between. In fact, they can't even be said to exist in between. They disappear from one orbit and appear at another. Once we remove such external stimuli, the electrons will jump back to their original orbits releasing energy in the process.

This is the famous quantum leap, and was first described by Bohr in 1913. When an electron jumps from an outer orbit into an inner one, energy is released in the form of a quantum of light called a photon. The abruptness of the change in energy, and the fact that electrons jump instantly from one position to another nonadjacent one, without actually passing physically in between, explains the common use of 'quantum leap' to mean 'radical and sudden change of circumstances'. To my knowledge physicists prefer the term quantum jump when describing this theory.

The problem with Bohr's theory is that, while it does account for a variety of observed phenomena, it can never be proved through observation. What I mean to say by that, is that you can't put an atom under a microscope and watch it's electrons jumping orbit.

Because of this reason a number of rival methods and theories sprang up in response to Bohr's research but since they don't belong in this node, I shall speak of them elsewhere...

Well I hope that this loosely explains the analogy of how Samuel Beckett supposedly jumped around from one universe to another!
Theorizing that one could time travel within his own lifetime, Dr. Sam Beckett stepped into the quantum leap accelerator... and vanished!

He awoke to find himself trapped in the past, facing mirror images that were not his own and driven by an unknown force to change history for the better.

His only guide on this journey is Al, an observer from his own time who appears in the form of a hologram that only Sam can see and hear.

And so Dr. Beckett finds himself leaping from life to life, trying to put right what once went wrong and hoping each time that his next leap will be the leap home....

Quantum Leap was a drama/science fiction TV program introduced in the spring of 1989 and continued until the summer of 1993, for a grand total of 95 episodes. Scott Bakula played Dr. Sam Beckett (no relation to the playwright), a scientist with six doctorates and fluency in eleven languages, living and dead. He also built the quantum leap accelerator chamber, which uses some dodgy applications of superstring theory to let a person travel back and forth through time within their own lifetime. The premiere begins when Sam puts himself into the chamber before it's completely ready, and ends up travelling back to the 1950s, but in someone else's life instead of his own. Worse, he's got no memory of who he's supposed to be; he only knows he's not the person he's "leaped" into.

Then Al shows up. Rear Admiral Albert Calavicci (Dean Stockwell) was Sam's best friend and ally when the accelerator was being built, and due to some more dodgy science is able to communicate with Sam in the past via an imaging chamber which projects him directly into Sam's mind (and past) as a sort of hallucination. Al advises Sam on where he is and what he's up to, aided by an intelligent computer at the accelerator site named Ziggy who sorts through historical documents in order to find out where Sam is and what he's up to.

Nobody really knows why Sam is stuck in the past, or why he keeps leaping from one person to the next, but everyone's best guess is that he substitutes in for someone else, generally in a time of personal crisis, in order to "put right what once went wrong." Once he's set things right, he leaps again into someone else's life and starts the whole process again.

For a while he tried to explain to people he met in the past what was really going on, but they never believed him because he didn't look like Sam. Thanks to some even more dodgy science, Sam switched places in time with his target but each of them would then be surrounded by the "aura" of the other, so that Sam looked like the person he was replacing and vice versa. Only Al could see them for who they really were, a consequence of being wired directly into Sam's neurons as part of the hologram/hallucination process.

From time to time the stories touched on the question as to why Sam kept leaping from person to person, trying to do good in their lives at times when they couldn't do it themselves. God, Fate and Time were the leading responsible candidates, but in the last episode it was learned that it was Sam himself, subconsciously guiding himself through time to help people who needed it most. Once he's made aware of this, he's able to leap through time with his own body instead of switching places with others, and apparently didn't need the accelerator chamber anymore, either. The finale ended with the simple message that Al's own life had been changed forever thanks to Sam's intervention in the past, and that Dr. Sam Beckett never returned home, the one thing he always said he wanted most.

I think that last fact sums up why I loved this series so much. Sure, it was technically science fiction, but only in the premise. The stories themselves were nothing of the sort, except when the occasional bit of technology from the future was needed to help achieve Sam's goal. And Sam was a man to be admired, the ultimate nice guy, brilliant and gentlemanly and helpful and kind to everyone he met. He never took advantage of people, he helped everyone he met, and he never gave up on doing what needed to be done wherever he went. Al would occasionally egg him on to follow his (or at least Al's) baser instincts, especially where women were concerned, but Sam held to his morals. No matter what the cost, he always tried to do the right thing.

I still remember the show fondly for that. In a television world full of sex, violence and duplicity, Sam was a role model people could believe in. The science fiction was just an added bonus.

The phrase "quantum leap" has been generalised in common speech to mean a big step forward. It sounds like impressive scientific jargon, but it is technically incorrect. A quantum in Quantum mechanics is the smallest possible discrete unit. A quantum leap is a change that emits a quantum. It is the smallest possible step forward. It may be discontinuous and sudden; but it is not big, radical change. It is a sub-microscopic increment.

Don't use this phrase to mean "a big change"1. If you feel the need to get pretentious and use big words, say "paradigm shift"2 to mean a fundamental change. At least you'll be making sense.

Or you could just say "a big step forward".

1) It makes you sound ignorant, and makes me wince. It's a pet hate of mine, like very unique, though not as bad.

2) For instance the change of mindset in the advance from Newtonian physics to Quantum mechanics.

Log in or register to write something here or to contact authors.