Sounds from the Big Bang

What a great article! I've clipped some of the tantalizing parts & added some emphasis:

Have you ever wondered what the "Big Bang" actually sounded like? Surely, you may be thinking, this is a trick question -- didn't it just sound like, well, a really big BANG! Surprisingly, perhaps, the answer is "no, not really". As is often the case with Nature, things are not so simple, and a more accurate description would be something like this: a moment of silence followed by a rapidly descending scream which builds to a deep roar and ends in a deafening hiss.
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Compared to concert pitch A, for which 440 sound waves pass us each second, a typical cosmic sound wave takes more like 50,000 years to pass by, about 50 octaves below the human range! On reflection, this is not too surprising -- something as large as the Universe must surely have an exceedingly deep voice; and indeed it does. Using a musical instrument as metaphor, the cosmic concerto is played on an ultra-ultra-bass piano, the seventh in an ever deeper series extending below the range of a human piano -- a truly GRAND piano of cosmic proportions [Figure 2]. With this in mind, we might now ask: what was the piano made of; who played it; and what music was being played? Here are the answers: the pianist's name was Gravity; his instrument was made of dark matter; and he played a single powerful chord which contained hidden within it both sadness and joy.
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The Universe is actually playing a chord! This bizarre property is tricky to understand, but worth the effort. Most musical instruments generate a harmonic sequence of tones because they have a fixed size. Between their ends (either strings or columns of air) one can fit only a whole number of waves; one, two, three etc; and this sequence of waves generates the sequence of harmonics. Now, although the Universe has no ends or edges, it is bounded in time. At any given moment, there has been a finite time since the Big Bang, and so there are specific region sizes across which exactly one, two, three, etc, full sound waves have passed. The sound waves created from these regions are, in a sense, louder than sound waves from regions of intermediate size, and hence they dominate the sound and create the harmonics. It is even possible to analyze the harmonic sequence and figure out what the chord actually is. Choosing the lowest two harmonics (which are the loudest) we find a slow change across the first million years from a major third (4 semitones) to a minor third (3 semitones).

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Read the rest! My thanks for Mark Whittle, Professor of Astronomy at University of Virginia, for dumbing down some of these concepts for us, so that we can begin to appreciate the meat of the matter!

What I find particularly interesting is the idea of the Universe being defined and bounded by Time. Time is the early key factor in determining pitch. Instead of physical length, such as a string or a tube, the the size of this instrument is based on the lengths of light years!

Al Asr

In the Name of Allah. the Most Compassionate, Most Merciful
By Time!
Man is truly in a state of loss,
save those who believe, and do gooddeeds,
and counsel each other unto the truth,
and counsel each other to be steadfast.