There is no such thing as time, except as a perceptual extrapolation of repetition and counting. This fact may be difficult to grasp for those accustomed to the modern commonplace of time as a fourth dimension on a real number axis, but even science continues to discover that there is simply no such thing as a continuum, as one model repeatedly gives way in layers to a finer model. For the ancients, time was something to be measured directly by counting, whether counting the motions of the celestial bodies, or counting one's own heartbeat. Of course, this remains true in our own lives, despite the convenience of a theoretical continuum, as the days and years pass. Even at its most advanced and scientific today, time is calibrated by measuring atomic vibrations. So there it is, repetition and counting again, in the guise of waves and their peaks & valleys. Of course, the most natural vibration in human perception is sound, the vibration of a body making a musical note. The musical note is the central vibration of perception, extending directly to rhythm & tempo at somewhat lower speeds, and timbre at somewhat higher speeds. The idea of vibration even extends naturally into the electromagnetic spectrum, to light and radiation at the high end, and also downward to the physical cycles of the planets. If there is to be a theoretical continuum, it exists in the translation of vibration, from one model to an adjacent one, yet vibration itself is necessarily a discrete phenomenon built on repetition and counting.
The idea of a Universe in vibration — as vibration — is certainly not a new one. This is the idea of Nada-Brahma, of the Universe as sound. Music is then the perceptually canonical example of vibration as a manifestation of reality in layers of vibration. If, as the cliché goes, time is what keeps everything from happening at once, and time is merely an extrapolation of repetition and counting, then why not perceive everything at once? This is the motivation for the Hindu cosmological iconography of bubbles within bubbles, as simultaneous perception of vibration enclosed within itself again & again. It is a meaty concept, to be sure, but again what of science? First of all, let me note the mathematical "consistency relations" which dictate an equivalence between redundant instantaneous analog sampling and the correspondingly "redundant" extension of that sample in time. This is a basic fact of signal processing, and has its correspondence in consistency relations for thermodynamic aggregates of statistical collections. Furthermore, thermodynamic entropy meets its precise mathematical analog in the "information function" of ergodic and information theory, and consequently the entropy-time correspondence of nonequilibrium physical processes is reflected precisely by an information-based interpretation. In other words, an entropy-time transformation to linearize a sequence of hypothetical events for the Big Bang, based upon background measurements which are already taken in the present and throughout the Universe, not only removes time from the equation and views everything as hypothetically simultaneous, but is expressed ultimately as a limit on information, on what we know, on perception. Hawking does not see it as such, but that is his loss.
Well, the above is a rather far-flung paragraph, and I hope you will forgive the indulgence. I wanted to suggest not only that the Universe-as-vibration model is virtually indisputable, but that the bubble-in-bubble-of-perception idea makes a great deal of sense as well, at least when considered properly. In another life (i.e. ten years ago), I was an expert on nonequilibrium thermodynamics and ergodic theory. We look through all of these simultaneous bubbles, and where they become too cloudy to distinguish what is farther inside we call the beginning of "time." Now, as for music.... The analogy between this slant on physics and my so-called retrospective view in aesthetics is fairly clear, as is the danger it implies. It is extension in time, or its Italian "tempo," which makes music; it is performed forward of course, but also remembered. So music orders time in myriad ways, and in the process manipulates our perception of reality, a perception which may be closer to "reality itself" than sometimes described. As far-ranging as these ideas may appear, they have already been gathered together by such modern composers as Stockhausen. When dealing with the medium of the magnetic tape in the 1950s, relations such as the equivalence of oversampling & extension in time, as well as the gradation between note & rhythm & timbre, became evident to composers, and they were forced to take notice of these facts. This view of time was alloyed to a fascination with other cultures and ultimately, for some, an obsession with space and cosmology.
What these relationships serve to reinvigorate is the knowledge that music is potent, that it affects one's perception of time. In the most basic sense of whether one is mentally occupied, it is virtually a truism that time passes more or less quickly, even for supposedly equal nominal quantities. There is the saying that "time flies" and also a feeling that the greatest moments of one's life are so large that one can literally be swallowed inside them. Similarly, there has been a suggestion that familiar pieces of music are performed more slowly in order to satisfy the audience's desire to let the moments linger. Recalling the earlier discussion on relative vs. absolute tempo, one might suggest that a great work's perceptual bubble expands over time, much like the Universe. Indeed such a repetition in performance can take on not only the quality of time itself, but an air of ritual. In that sense, one aspect of HIP has been to divest music of this accumulated ritual. Just as measuring the radiation of the farthest reaches of the Universe in an effort to discover the smallest kernel of its initial existence suggests a correspondence between the largest and smallest elements (and ultimately a circular conception of spatial simultaneity which accompanies a negation of time), it is an ability to invest "the moment" with the greatest possible weight and significance which can conceivably synchronize & open oneself to the largest expanses. Consequently it is styles of pointillism which have frequently replaced melodic continuity in postmodern music. The extent to which cosmology enters contemporary composition is a tangible link to the medieval era, even if its expression has been rather different.