There is such a thing as historical memory. But, as Kirkegaard tells us, there’s nothing to guide the individual soul. For us time starts where memory goes back to. In a recent story, the writer, Dan Jacobson, imagines a man dropping a stone into a pit and waiting for a reverberation which never comes back to him. "That is what the past is like," he says, "echoless and bottomless. Only its shallowest levels, those closest to us, have recognizable colors and forms. So we fix our gaze there. Below them is a darkness that gives back nothing."

For an individual time is bounded by memory, or by his birth and death. Memory speaks to him as nothing else can; that forms his private universe. He finds it hard to believe that there was a time when he was absent, or there will be one in the absence to come—Nabokov’s two eternities of darkness. Nabokov relates the experience of a ‘chronophobiac’ seeing movies of his family taken in his absence, that is, a few weeks before his birth. He was frightened by the sight of his pregnant mother, and the baby-less carriage. No one mourned his absence. The world didn’t exist for him then.

The nature of memory is such that it affects our perception of time—that is, psychological time; it can play tricks with our mind. Going back in time with your memory, or retrieving memory as it were, is a form of time travel. In a more profound sense, memory is identity, an identity constantly redefining itself as memory accumulates over time.

So memory shapes a man’s perception of time. We might well ask, "What causes the illusion of the passage of time?" The mathematician, Kurt Gödel gave this answer:

"The illusion of the passage of time arises from the confusing of the given with the real. Passage of time arises because we think of occupying different realities. In fact, we occupy only different givens. There is only one reality."

Since reality never changes, we suffer from the illusion of feeling like prisoners of time.

We speak of being in a ‘time-warp’ in the sense of occupying a world that is out of tune with a supposed ‘present’. In a sense that is the ‘given’ in Gödel’s interpretation.

Arguably, the last true frontier is the human mind, not the observable universe 'out there' which we perceive and make sense of with that mind. We are for the most part where our minds are. To that extent we live in a symbolic universe, in a time and space of our own choosing. Time and space are constantly being distorted to fit our perceptions. We think back, we think ahead, forever avoiding the present, which is too real, too close for comfort. All our records and chronicles are tinged with the virtual—that's how we represent the supposedly real. Our concern, first and foremost, is how we think and feel, what we imagine. As Gödel might have said, the real is confused with the given, and so illusion reigns.

Nostalgia is the prism through which we write our revisionist histories—the way we think things were at that time but really weren't, but the way we would like them to be like now, which they can't be. And of course there will come a time when we are nostalgic about this present, though we can't imagine how or why. That is the nature of time as the mind experiences it. Time never stands still, though as Godel said, the real never changes--we only confuse the given with the real--the givens change and so time is perceived as passing.

Any real time travel would mean a physical undoing to inhabit past states. But for whom, from whose point of view? Gödel’s notion of the given vs. the real sheds some light on this question. The idea of a parallel universe seems to make time travel possible at least in principle: the classic Young double-slit experiment, performed with light reduced to a single photon, somehow yielded another photon. Where did it come from? Wave-like objects, in contrast, are smeared out. A particle behaving like a wave can, for example, seem to pass through two slits in a barrier simultaneously. When this happens, the two waves emerging from the slits may interfere with each other.

This thought, however, nags: would the time traveler be an observer or a participant? One can’t imagine a selective journey by one conscious soul who witnesses the undoing of everything but himself. To actually re-live or re-witness a past event means that cause-effect would have to be entirely reversed, as in a grand, all-encompassing film of the entire human race run backwards. Gödel might have pointed out that we are already there since there is only one reality, and the ‘past’ is but an illusion.

Our concept of time was altered forever when Einstein’s thought experiments led him to his Principle of Relativity. Time is relative, meaning that its measurement depends on the observer’s frame of reference. The speed of light, however, is independent of that frame and is thus a universal constant. Einstein imagined a rider on a tram moving away from a clock at the speed of light. Since the rider must read the clock by the light reflecting from it, its hands appear not to have moved at all. At that speed time comes to a standstill for the rider. This is the ‘apparent’ slowing down of time with increasing speed. But what can this really mean for an observer at rest who reads that clock?

Common sense tells us that time must be linked to space; otherwise what would the relativity of time mean? We perceive or become aware of the passage of time because of change, because of event. And an event is inherently spatial in nature. It is a kind of perturbation. Indeed, the measurement of time, the standard reference for our clocks, is the regular perturbation, or vibration frequency, of the cesium atom. Writing in the magazine Discover, Tim Folger puts it another way: "We live, Hermann Minkowski (one of Einstein's teachers) said, in a four-dimensional world: three of space and one of time. When we see the sun, for example, we're looking not just at an object in space but at a time as well. We see the sun not as it is but as it was eight minutes ago, the time it takes the sun's light to reach Earth. Space does not exist separately from time. Or as Minkowski himself put it, "Nobody has ever noticed a place except at a time, or a time except at a place."'

The relativity of time refutes the universal flow of time postulated by Newton.

Time and space are intimately connected according to relativity theory, and form a four-dimensional continuum. The beginning of time was also the beginning of space. Both are bound by matter, which was created from a singularity a finite time ago—the Big Bang which began our expanding universe. But Indian thought embraces eternal time, without beginning or end; an infinity of time. Shaivism posits a belief in ‘spontaneous being’—that is, the universe as we know it has always existed: it never came into being, nor will it ever cease to be. Timelessness implies a world beyond the ambit of measured time. Ideas of the ‘given’ and ‘relative-apparent’ seem to bring Gödel’s and Einstein’s scientific thinking closer to the multiple expressions of ‘spontaneous being’. The cosmos is indeterminate with regard to time and space.

The idea of a rhythmically expanding and contracting universe was a part of ancient Indian mythology: the Hindus experienced the universe as an organic, rhythmically moving cosmos, and could develop cosmologies which come very close to modern science. One of these is based on the Hindu myth of lila in which Brahman transforms himself into the world. Lila is a rhythmic play that goes on in endless cycles. This rhythmic divine play served as a metaphor for the evolution of the cosmos as a whole. The Hindu sages perceived a universe expanding and contracting periodically, and called the vast time between the beginning and end of one creation kalpa.

The well-known Marathi saying bears repeating: Kaal ala pun wel ali nahi (The time has come but not the moment). This suggests a unified concept of time and space where extended space is extended time, and a point is an instant as in the word ‘avakaash’ , which means a while or an interval of time; and akaash means, literally, sky, which in turn implies stretched space. So avakaash subsumes both time and space, and thus has an in-built compound meaning. It expands the concept of time itself.

Indian culture adheres to the idea of cyclical time; the history of a race mimics the life of an individual—endless cycles of birth and death overlap and follow one another. In contrast, the linear time implicit in Christian doctrine and the Western concept of history insists that the race as a whole continues to grow, develop and progress, without turning back. There’s an irony here. Many in the West are turning to the study of Eastern civilizations, that is, coming back to the beginnings of civilization. Is this not a kind of cyclical movement in itself? As though mankind strayed from the centre or origin only to come back to it?

The rhythm or taal in Indian classical music is cyclical in nature; an aavartan, or an improvisation in a raga recital, may stretch over several cycles but is resolved upon arrival at the sam or first beat of the time cycle. The 4/4 time of Western classical music, or jazz, is in theory cyclical (as any cycle of beats obviously is) but the duration is so short that one gets the impression of a musical progression along an indefinite linear path. It is the idea of movement or development over longer time cycles which distinguishes the Indian classical system. For instance, in teentaal, a cycle of 16 beats, the division into four equal parts of stressed and unstressed beats, with an emphatic absence of stress, or khali, in the third part, serves to stretch out the basic four-beat time cycle while at the same time avoiding repetition, thus giving the overall impression of time delayed. By its use of off-beats or syncopation, it has some affinities with jazz, also an improvised music. The theka in some film or folk music, borrowed from punjabi geets, is a kind of 4/4 time.

Naad, or resonance, carries with it the notion of movement; an andolan, or in Western terms, dance; hence music becomes song and dance. In the Natyashastra, sangeet, or music, encompasses singing, the playing of an instrument and dancing.

Musical time is in essence ‘dream’ time—it hints at an ‘alternative’ time; it gives one the experience of being in another, more congenial world—it transports you into an imaginary realm, allowing you to temporarily forget the real world and real time, as indeed fiction does. Nabokov was a shamanstvo, an enchanter. His idea of fiction is best told in his own words: "For me a work of fiction exists only insofar as it affords me what I shall bluntly call aesthetic bliss, that is a sense of being somehow, somewhere, connected with other states of being where art (curiosity, tenderness, kindness, ecstasy) is the norm".