Sanjoy Nath's Qhenomenology reasoning for Waves Topology presents a radical departure from
conventional signal processing, proposing a novel, time-domain, and
topology-centric framework for wave analysis. This abstract outlines its core
tenets, suggests mathematical formalizations, and compares it to related fields
like Topological Data Analysis, signal grammars, and symbolic dynamics.
Research Abstract: Qhenomenology: A
Topological-Combinatorial Framework for Waveform Analysis
Abstract: Conventional digital signal processing, heavily reliant on
Fourier analysis, often focuses on spectral content, potentially obscuring
time-domain morphological features critical for certain information extraction
tasks. This paper introduces Qhenomenology,
a novel axiomatic framework for waveform analysis that fundamentally redefines
signal interpretation. Diverging from sinusoidal decomposition, Qhenomenology
treats waveforms as ordered sequences of topologically classified Axis-Aligned Bounding Box (AABB)
objects: "Crest AABBs," "Trough AABBs," and "Silence
AABBs."
The core innovation lies in: (1) a precise methodology for
normalizing signals via a median-centered baseline, yielding "crisp
zero-crossing points"; (2) the extraction and intrinsic topological numbering of individual
AABBs based on scale-invariant properties (e.g., local extrema counts,
monotonic segment lengths, and percentile ranks of boundary amplitudes),
encapsulated in a "Sensitiveness Number"; (3) a novel classification
and topological numbering system for zero-crossing
"junctions" (e.g., Crest-to-Trough, Trough-to-Silence),
incorporating neighborhood rank information; and (4) the identification and
topological categorization of "Container AABBs" representing complete
wave cycles or meaningful segments, derived from specific combinatorial
patterns of constituent AABBs and junctions. Qhenomenology asserts that
information critical for perception (e.g., musical tonality, percussions)
resides in these topological-geometric arrangements rather than exact amplitude
values or harmonic superpositions. This framework transforms time-series
analysis into a "stringology" or "grammar parsing" problem,
enabling pattern matching and algebraic reasoning on sequences of topologically
numbered symbols. This approach promises to uncover distinct waveform features
essential for applications where conventional methods fall short, without
recourse to Fourier transforms or statistical machine learning for core
classification.
Mathematical Formalizations for Peer-Reviewed
Publication
To formalize Sanjoy Nath's Qhenomenology for peer-reviewed
publication, a precise mathematical language is essential. Here are proposed
formalizations:
1. Signal Representation and Baseline
Normalization
Let S={s[n]}n=0N−1 be a discrete-time signal of length N, where
s[n] is the amplitude at sample index n.
Axiom (Median
Baseline): The fundamental zero-amplitude reference line is established by the
global median of the signal.
Definition 1.1
(Median-Centered Signal):
Let
smed=median(S). The normalized signal S′={s′[n]}n=0N−1 is defined as:
s′[n]=s[n]−smed
2. AABB Object Definition and Properties
Definition 2.1
(Amplitude Type Function): Given a silence threshold δ>0:
AmpType(x)=⎩⎨⎧CrestTroughSilenceif x>δif x<−δif −δ≤x≤δ
Definition 2.2 (AABB
Object): An AABB object Ak is a contiguous segment
of the normalized signal S′ defined by indices [nkstart,nkend] such that:
1.
All samples s′[n] for
nkstart≤n≤nkend have the same AmpType(s′[n]) (ignoring boundary transitions
for definition of the AABB itself).
2.
It is maximally
extended, meaning s′[nkstart−1] (if exists) and s′[nkend+1] (if exists) have
a different AmpType than samples within Ak.
3.
Each Ak is assigned its
Type(Ak)∈{Crest, Trough, Silence}.
Definition 2.3 (AABB Properties for
Ak):
Let Ak={s′[n]}n=nkstartnkend
be an AABB with Wk=nkend−nkstart+1 samples.
●
Width: Wk=nkend−nkstart+1
(in samples). Can be converted to microseconds: Wkµs=Wk/SampleRate×106.
●
Area Under Curve:
Area(Ak)=∑n=nkstartnkends′[n].
●
Monotonicity Counts:
○
MI(Ak)=∑n=nkstart+1nkend1s′[n]>s′[n−1]
○
MD(Ak)=∑n=nkstart+1nkend1s′[n]<s′[n−1]
○
where 1condition is the
indicator function (1 if condition is true, 0 otherwise).
●
Local Extrema Counts: Lmin(Ak), Lmax(Ak)
(number of local minima/maxima within Ak).
●
Absolute Amplitude
Percentile Ranks:
Let Sabs(Ak)={∣s′[n]∣}n=nkstartnkend be the set of absolute
amplitudes within Ak. Let Sabssorted(Ak) be this set sorted in ascending
order.
○
PRL(Ak)=percentile_rank(∣s′[nkstart]∣,Sabssorted(Ak)).
○
PRR(Ak)=percentile_rank(∣s′[nkend]∣,Sabssorted(Ak)).
(The percentile_rank(value, sorted_list) function returns the
proportion of values in sorted_list less than or equal to value).
3. Topological Sensitiveness Number for AABBs
Definition 3.1
(AABB Topological Sensitiveness Number, TS(Ak)):
This metric
quantifies the topological "shape" of an AABB, designed to be largely
scale-invariant and to "forget" exact amplitude details.
TS(Ak)=⌊∑j=nkstartnkend∣s′[j]∣+ϵArea(Ak)⋅105⌋(Normalized
Area Term)+⌊WkMI(Ak)⋅104⌋(Normalized Monotonic Increase
Term)+⌊WkMD(Ak)⋅103⌋(Normalized Monotonic Decrease
Term)+PRL(Ak)⋅102(Leftmost Sample Percentile Rank
Term)+PRR(Ak)⋅101(Rightmost Sample Percentile Rank Term)+103Wk(Normalized
Width Term)
where ϵ is a small
positive constant to prevent division by zero, and floor ⌊⋅⌋ operations
discretize the contributions. (Note: The TotalArea_ofThisAABB in the original
text is interpreted as sum of absolute samples for normalization, making the
area term a ratio reflecting general amplitude distribution, insensitive to
scale).
Definition 3.2
(AABB Global Rank): AABB objects are ranked globally based on their TS(Ak)
values.
Rank(Ak)=position
of Ak when all Aj are sorted by TS(Aj).
Definition 3.3 (AABB
Scale Factors): For each topological
class (AABBs with the same Rank(Ak)), identify the widest AABB, Awidest.
●
SFX(Ak)=Wk/Wwidest
●
SFY(Ak)=(MaxAmp(Ak)−MinAmp(Ak))/(MaxAmp(Awidest)−MinAmp(Awidest))
4. Zero-Crossing Junction Classification
Definition 4.1
(Zero-Crossing Junction): A zero-crossing
junction Jm occurs at sample index m where AmpType(s′[m−1])=AmpType(s′[m])
(or equivalent, between AABB Ak and Ak+1).
Definition 4.2
(Junction Type, Type(Jm)): Categorized based on the types of adjacent AABBs:
Type(Jm)∈{CT, TC,
TT, CC, SS, ST, TS, SC, CS, Undefined}
Definition 4.3
(Junction Topological Number, TJ(Jm)): A unique, scale-invariant identifier
for a junction based on its type and the topological properties of its
neighboring AABBs.
TJ(Jm)=Hash(Type(Jm),PRR(Ak),PRL(Ak+1),Type(Ak),Type(Ak+1))
This hash captures
the local topological context of the crossing.
5. Container AABB (Cycle) Definition and Classification
Definition 5.1
(Container AABB, Cp): A Container AABB Cp is a sequence of contiguous AABB objects
{Ai,Ai+1,…,Aj} that represents a "complete cycle" or a
perceptually meaningful segment of the waveform. In this framework, such a
container is typically delimited by specific topological junction types (e.g.,
a cycle starting with a TC junction and ending just before the next TC junction
of a specific type).
Definition 5.2
(Container AABB Topological Sensitiveness Number, TS(Cp)): A composite metric
reflecting the topological "essence" of the entire container, derived
from its aggregated internal properties.
TS(Cp)=AggregatedFunction(Count(Ak∈Cp),Count(Jm∈Cp),Sum(Lmin(Ak)),Sum(Lmax(Ak)),…)
This function needs
to be explicitly defined, but it would combine the scale-invariant properties
of its contained AABBs and junctions.
Definition 5.3
(Container AABB Global Rank): Containers are ranked
globally based on their TS(Cp) values.
Definition 5.4
(Container AABB Scale Factors): Similar to AABBs, but
for containers. Identify the widest container Cwidest within the same
topological class (same Rank(Cp)).
●
SFX(Cp)=Width(Cp)/Width(Cwidest)
●
SFY(Cp)=(MaxAmp(Cp)−MinAmp(Cp))/(MaxAmp(Cwidest)−MinAmp(Cwidest))
(where MaxAmp/MinAmp of container means global max/min of samples within it).
6. Waveform as a Formal Language
Proposition 6.1
(Symbolic Waveform Representation): The timeline of a wave can be represented
as a formal string of symbols Σ∗, where Σ is the alphabet of topologically
numbered AABB objects and zero-crossing junctions.
Example:
Σ={(AType,TS(A)),(JType,TJ(J))}.
A waveform might be
represented as: (ACrest,TS(A1))(JCT,TJ(J1))(ATrough,TS(A2))(JTC,TJ(J2))…
Proposition 6.2 (Grammar
and Pattern Matching): Specific wave
"patterns" (e.g., musical phrases, distinct vibrations) can be
recognized and categorized by defining a formal grammar G over Σ∗. Regular
expressions or more complex parsing algorithms can be applied to identify
occurrences of these patterns, allowing for "compilability checking"
of wave structures.
Comparison to Specific TDA, Signal Grammar, or
Symbolic Dynamics Models
Sanjoy Nath's Qhenomenology is unique due to its foundational
axioms and explicit rejection of Fourier. However, it shares conceptual
commonalities with several advanced analytical paradigms:
1. Comparison to Topological Data Analysis (TDA)
●
Similarities:
○
Focus on Shape/Structure: Both TDA and
Qhenomenology prioritize the underlying shape and structure of data over
precise numerical values. Both seek "invariant properties."
○
Abstraction and Feature Extraction: Both aim to extract meaningful, low-dimensional features that
describe complex high-dimensional data.
●
Differences:
○
Fundamental Primitives: TDA typically
constructs abstract topological spaces (e.g., simplicial complexes,
Vietoris-Rips complexes) from point clouds or metric spaces. Features are then
derived using algebraic topology (e.g., Betti numbers from persistent homology,
which count "holes" of different dimensions). Qhenomenology,
conversely, uses concrete, geometric
AABBs directly on the time series as its fundamental building blocks. Its
"topology" is defined by specific arithmetic combinations of derived
AABB properties rather than abstract homological invariants.
○
Metric Definition: TDA relies on metric
spaces to define proximity and build complexes. Qhenomenology's
"Sensitiveness Number" is a custom, composite metric for AABBs
themselves, not directly for a point cloud representation of the wave.
○
Zero-Crossing Emphasis: While TDA can reveal
features related to "loops" or "cycles" in data, it does
not have an inherent mechanism for "zero-crossing point
classification" with specific semantic labels like CT/TC based on signal
sign changes as a primary topological feature.
2. Comparison to Signal Grammar and Formal
Languages
●
Similarities:
○
Symbolic Representation: Qhenomenology's
transformation of the continuous waveform into a "strict queue of
symbols" (AABBs and classified junctions) aligns perfectly with the core
idea of symbolic representation in signal processing and formal languages.
○
Pattern Recognition: The use of
"regular expressions" and "grammar parsing" to identify
patterns in these symbolic sequences is a direct application of formal language
theory.
○
Compositionality: Both allow complex
signals/messages to be understood as compositions of simpler, meaningful units
according to defined rules.
●
Differences:
○
Symbol Granularity and Richness: In typical signal grammars (e.g., for speech, music), symbols
are often derived from simpler features like amplitude thresholds, frequency
bands, or short-time spectral characteristics. Qhenomenology's
"symbols" (AABBs and Junctions) are inherently richer, carrying internal topological "sensitiveness
numbers" and other complex morphological properties that are
scale-invariant. This provides a much deeper semantic content for each symbol
than a simple categorical label.
○
Axiomatic Basis: The "compilability
as existence" axiom and the derivation of "dictionary order"
from class dependencies are unique meta-level philosophical constructs not
found in standard signal grammar frameworks.
3. Comparison to Symbolic Dynamics Models
●
Similarities:
○
Discretization and Sequence Analysis: Both symbolic dynamics and Qhenomenology convert
continuous-time dynamics (or signals) into discrete sequences of symbols for
analysis.
○
Focus on Patterns and Complexity: Both fields aim to understand the underlying patterns,
structure, and complexity within these symbolic sequences.
●
Differences:
○
State Space Partitioning: In symbolic dynamics,
the continuous state space of a dynamical system is partitioned into a finite
number of regions, and each time the system enters a region, a corresponding
symbol is emitted. Qhenomenology's "partitioning" is explicitly based
on the segments of the waveform determined by zero-crossings and silence,
creating the AABB objects directly from the time domain signal.
○
Symbol Definition: While symbolic dynamics
symbols are typically simple labels (e.g., '0' or '1'), Qhenomenology's AABB
symbols encapsulate rich, multi-dimensional topological information (the
sensitiveness number and other derived properties).
○
Reconstruction and Meaning:
Symbolic dynamics focuses on properties of the symbolic sequence that reflect
the original dynamics. Qhenomenology explicitly claims that altering amplitude
details while preserving CG geometry can generate "same spectral
behaviors," suggesting a unique perspective on information and
reconstruction.
In conclusion, while
Qhenomenology shares a family resemblance with time-domain morphological
analysis, symbolic representation, and topological thinking in data analysis,
its specific axiomatic foundation, the definition of AABB primitives with their
unique topological metrics, and the ambitious claim of replacing Fourier
analysis make it a distinct and novel
theoretical framework. Further research would be needed to rigorously
validate its claims and explore its full potential across various signal
domains.
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