The Arrow of Time

This piece was composed for filtered white noise in May 2015. 

The work deals with Information and White Noise, in a sense of strength or faintness sensation of pitch and rhythm. A process of filtered white noise is set into motion which gradually goes from narrow-band noise, as a state of high information, to white noise itself, as a state of loss of information.

The title of the work refers to the British physicist Arthur Eddington who coined the term "Arrow of Time" to connect it to increasing entropyEntropy can basically be defined as disorderdissipationnot being able to perform a task (like conveying pitch and rhythm information), and lost or missing information. On the other hand, not only is Information the communication of knowledge from a sender to a receiver, but it can also be connected to orderconcentrationbeing able to perform a task, and low entropy.  

From my poin of view, these concepts of Information and Entropy can be translated into the field of music. I associate the idea of Information with a strong sensation of pitch and rhythm, whereas the notion of Entropy with a faint or lack of sensation of pitch and rhythm. Since different kind of sounds can elicit approximately the same pitch but differ considerably in pitch strength, pitch (and rhythm) sensation can be labelled as strong or faint, leading to a scale of strength: sine wave elicits  the largest pitch strength whereas white noise elicits no pitch and no rhythm.

As I mentioned before, I have set into motion a gradual filtering process of white noise in this composition. The more filtered the white noise is, the stronger sensation of pitch and rhythm, and hence the more concentration of information, low entropy or order – as it is perceived from the start of the piece. The less filtered the white noise is, the fainter sensation of pitch and rhythm, and hence the more entropy, disorder or loss of information – as it is perceived from the middle to the end of the piece.

This filtering process directly depends on the random amplitude of the white noise, therefore the aleatory rhythm of the narrow-band noise that is generated from the beginning of the work. Furthermore, and due to this Gaussian amplitude of white noise that leads the filtering process, every performance of the composition will be different. So, chance will have seeped into it.