Almost 20 years ago I had a friend Dr Ion Ladea (d. 2001) who worked as a GP.
He was very much interested in Traditional Chinese Medicine, read a lot of books,
and learned the methods of examination and acupuncture.
We had long discussions about this subject, he asking me about some physical interpretation.
We did not done too much, but the Traditional Chinese pulse diagnosis appeared to be
appropriate for a physical interpretation.
My idea was based on an experiment I have seen in the last year of High School,
and the theory of string and air column instruments. The experiment was about the different
flow of a fluid (water) from a pulsating pump through a glass pipe, and a thin rubber pipe.
In fact was about the flow of blood, the heart being the pulsating pump.
Through the glass pipe one can see regions of water and regions of air (discontinuous flow),
while through the rubber pipe the flow is continuous, but the pipe takes a “wavelike shape”
with regions of a bit larger diameter and regions with a smaller diameter.
This explains the continuous flow of blood through the elastic blood vessels
(at least this was what the teacher told us).
Thinking that the heart is placed on the left, this means that the blood vessels from heart
to the left and right wrist are different. To ensure a continuous flow of blood they also “carry”
the signal of the heart rhythm (the pulse). In the Traditional Chinese Medicine there are three
points to take the pulse, and this can be seen as adjusting the length of blood vessel in the
same way as for string and air/fluid column instruments. More precisely, one has to consider
the radial artery pulse as it appears at three spatial locations (inch, gate, and foot) and
three depth locations (superficial, middle, and deep) in the left and right wrist area.
All these make adjustments of the length and type of radial artery (assuming it works like a
vibrating string or a fluid column) for 18 standing waves, or 18 frequencies.
I remember, I read somewhere that initially there were only two depth locations (superficial and deep)
which correspond to an open/closed end fluid column (or a string with a free/fixed end).
In this case the pulse diagnosis is nothing else but a Fourier analysis of heart signals (rhythm)
into 12 basic/fundamental frequencies which correspond to the 12 meridians in Traditional Chinese Medicine.
If the vibrations of one component exhibit some anomalies then the flow of energy through the
associated meridian (and the state of the corresponding internal organ) is abnormal.
That time, we had no chance to check this experimentally (and anyway I am a theoretician).
Now, I searched the Internet: there are a lot of web pages about the Traditional Chinese pulse diagnosis,
but I found nothing like this Fourier analysis interpretation. Thinking about the
differences between individuals (height, weight, arm length etc.) it seems that this set of
frequencies should be a characteristic of an individual or, at most, of a class of
individuals. It is a wonder that the doctors in ancient China managed to master all these.