Do you mean the Theravadin Abhidhamma's theory of momentariness?
That is not related to Madhyamaka's Shunyata (where all things are empty of substance or essence, including emptiness itself) or the nature of matter, or the universe. It however, relates to Theravadin Shunyata (i.e. all phenomena is empty of a self).
The Abhidhamma's theory of momentariness is applied only to the mind and mental processes. I don't fully understand it, but I see it as a quantization or discretization of mental processes into thought-moments or cittas.
This actually sounds very similar to how a computer CPU runs based on clock cycles, and its processes are quantized or discretized into processing of individual instructions (so-called instruction cycles), each taking a number of clock cycles. Each instruction has to be fetched, decoded, executed, and completed, before the next instruction can be fetched.
It is not far fetched to say that the Abhidhamma's model of mind and body is similar to the model of software and hardware in a computer. Both do not require a self or soul to function or run. And exactly, this is the point of Theravadin Shunyata i.e. sabbe dhamma anatta - all phenomena is not self.
Apparently, this is supported by scientific research. Please see "Consciousness Arises In Discrete Time Slices, Suggests Study" and "A time slice theory of consciousness suggests we’re not continually aware of our surroundings".
I quote below from The Abhidhamma in Practice by N.K.G. Mendis:
Awareness is the process of cittas experiencing objects. For a citta
to arise it must have an object (aaramma.na). The object may be a
color, sound, smell, taste, something tangible, or a mental object.
These are the six external objects. Strictly speaking a mental object
can be an internal phenomenon, such as a feeling, a thought, or an
idea, but as forming the objective sphere of experience they are all
classed as external. Corresponding to these external objects there are
six internal sense faculties, called "doors" since they are the
portals through which the objects enter the field of cognition. These
are the eye, ear, nose, tongue, body and mind. Each of the five
physical sense faculties can receive only its appropriate object; the
mind door, however, can receive both its own proper mental objects as
well as the objects of the five physical senses. When a door receives
its object, there arises a corresponding state of consciousness, such
as eye-consciousness, ear-consciousness, etc. The union of the object,
the door or sense faculty, and the consciousness is called "contact"
(phassa). There can be no awareness without contact. For contact to
occur all three components must be present — object, door, and
consciousness. If one is missing there will be no contact. The process
of the arising of consciousness and the subsequent train of events is
analyzed in detail in the Abhidhamma. A study of this analysis will
show that only "bare phenomena" are taking place and that there is no
"self" involved in this process. This is the no-self characteristic of
Mind in its passive and active forms
The mind occurs in both passive and active modes. The passive gives
way to the active when a stimulus is received through one of the sense
doors. The passive state of mind is called bhava"nga, cuti, or
paa.tisandhi, according to the occasion.
Bhava"nga. The bhava"nga citta, mentioned earlier, is the primary form
of mind. It flows from conception to death except when interrupted by
a stimulus through one of the sense doors. When a stimulus enters,
consciousness becomes active, launching into a thought process (citta
viithi). Thought processes have been analyzed in great detail in the
A complete thought process, occurring through the physical sense
doors, is made up of seventeen thought moments (citta kha.na). These
- A bhava"nga that flows by in a passive state when one of the five physical sense organs comes in contact with its object (atiita
- A bhava"nga that vibrates for one thought moment (bhava"nga calana).
- A bhava"nga that cuts off the flow (bhava"nga upaccheda).
- A citta that turns towards the object through the sense door that has been stimulated (pañcadvaara-vajjana).
- The appropriate sense consciousness; in the case of the eye, for example, eye consciousness (cakkhu viññaa.na).
- Next a thought moment — the sampa.ticchana citta — which has the function of receiving the object.
- When the object has been received another thought moment, called the santiirana citta, arises, performing the function of investigating
- The act (kamma) itself, especially if it was a weighty one.
9 to 15.
The object having been determined, the most important stage from an ethical standpoint follows. This stage, called javana, consists of
seven consecutive thought moments all having an identical nature. It
is at this stage that good or evil is done, depending on whether the
cittas have wholesome or unwholesome roots. Therefore, these javana
thought moments have roots and also produce new kamma.
16 and 17.
Following the seventh javana the registering stage occurs, composed of two thought moments called tadaalambane. When the second
registering citta has perished, the bhava"nga follows, flowing on
until interrupted by another thought process.
These thought moments follow one another in extremely rapid
succession; each depends on the previous one and all share the same
object. There is no self or soul directing this process. The process
occurs so rapidly that mindfulness has to be alert and brisk to
recognize at least the determining thought moment — the vottapana — so
that one can govern the javana thought moments by wholesome volition.
When the mind-door receives a mind-object, the sequence of events is a
little different from that occurring through the physical senses. The
mind-door-adverting citta is the same type of citta as the determining
moment — the votthapana — that arises in a sensory process. This
mind-door-adverting thought moment can cognize an object previously
seen, heard, smelt, tasted or touched, thus making memories possible.
Since the mind-object here has already been received and investigated,
these functions need not be performed again and the
mind-door-adverting thought moment gives way immediately to the
javanas. These are, again, of great ethical significance. For example,
unpleasant words previously heard can suddenly come to mind and,
unless proper mindfulness (sammaa sati) is practiced, call up javana
cittas rooted in hatred, i.e., unwholesome kamma.