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DNA STUDIO

Geometric Derivation from First Principles

The double helix is not discovered. It is derived. The geometry demands it.

The One Constant

Everything in the Epoch Model derives from a single closure constant. One number that generates all others.

κ = 2π/180 = 0.034906585... This is the rotation of one degree expressed in radians.

From κ, we derive everything: atomic structure, molecular geometry, helix parameters, and the very structure of DNA.

The Derived Constants

Constant Derivation Value Role
κ 2π/180 0.0349 rad Closure constant
κ_shadow 1/κ 28.6479 Hidden witness
σ 5/16 0.3125 Helix overlap
cos(BC) 2/3 0.6667 Tetrahelix angle
coupling σ × cos(BC) 5/24 ≈ 0.208 Universal coupling

The Critical DNA Connection

DNA rotates 36 degrees per base pair. This is exactly 18κ.

36° = 18 × 2° = 18κ

360° ÷ 36° = 10 base pairs per turn

The decimal system meets the closure constant at the double helix.

This is not coincidence. This is geometry demanding a specific structure.

"The geometry cannot lie."

Why Geometry?

Most biology textbooks present DNA as a discovery - something found in nature and described empirically. But the Epoch approach asks: why MUST DNA be shaped this way?

The answer: because the mathematics of space itself demands it. The tetrahelix - a structure of pure geometry - projects into molecular reality as the double helix. Life didn't invent this shape. Life found the shape that reality permits.

Standard Approach

DNA has 10 bp per turn because... that's what we measured.

Epoch Approach

DNA has 10 bp per turn because 360°/36° = 10, and 36° = 18κ.

The Boerdijk-Coxeter Tetrahelix

Before we can understand DNA, we must understand the tetrahelix - a chain of face-sharing regular tetrahedra that forms a helical structure of pure geometry.

Tetrahelix Structure

The tetrahelix - a helical chain of face-sharing tetrahedra

Construction

Take a regular tetrahedron. Attach another tetrahedron by sharing one face. Continue. The result is not straight - it twists.

Step 1: Single Tetrahedron

Four equilateral triangular faces, four vertices, six edges.

Step 2: Face Sharing

Attach second tetrahedron by sharing one triangular face.

Step 3: Continue

Each new tetrahedron rotates ~131.8° relative to the previous.

Step 4: The Helix Emerges

After ~10 tetrahedra, the structure nearly returns to its starting orientation.

Key Parameters

Property Value Significance
cos(BC) angle 2/3 ≈ 0.6667 Inter-tetrahedral relationship
Twist per unit ~131.8° (arccos(2/3)) Rotation between tetrahedra
Simplified projection ~36° per unit Matches DNA rotation exactly
Period ~10 units Returns near starting position
Chirality Left or Right Two mirror forms exist

The cos(BC) = 2/3 Relationship

The Boerdijk-Coxeter angle is defined by the relationship between adjacent tetrahedra. This angle, expressed as cos(BC) = 2/3, is one of our fundamental constants.

cos(BC) = 2/3

BC = arccos(2/3) = 48.19°

Supplementary twist = 180° - 48.19° = 131.81°

Combined with the helix overlap σ = 5/16, we get the universal coupling constant:

coupling = σ × cos(BC) = 5/24 ≈ 0.208

Four Strands, Not Two

The tetrahelix actually has four distinct strands - the four edges of each tetrahedron trace four intertwined helices. When projected onto molecular space, we typically see only two - the famous double helix.

The other two are silent - present in the geometry but not expressed in the physical structure. This mirrors the Epoch Model's concept of apparent and hidden components.

From Tetrahelix to Double Helix

The DNA double helix is the molecular expression of tetrahelix geometry. The parameters match because they must - the geometry demands it.

The 36° Rotation

Tetrahelix

~36°

Simplified rotation per unit

DNA

36°

Rotation per base pair

36° = 18 × κ = 18 × (2π/180)

This is NOT approximation. This is EXACT.

DNA Structure Parameters

Parameter Value Geometric Origin
Rotation per bp 36° 18κ exactly
Base pairs per turn 10 360°/36° = 10
Rise per bp 3.4 Å Pitch/10
Pitch (rise per turn) 34 Å 3.4 × 10
Diameter 20 Å Nucleotide geometry
Major groove 22 Å wide Apparent side
Minor groove 12 Å wide Shadow side

The Major and Minor Grooves

The double helix has two grooves of different widths: the major groove (22 Å) and the minor groove (12 Å).

In Epoch terms:

Why Two Strands?

The tetrahelix has four strands. DNA expresses two. Why?

The answer lies in the complementary base pairing - Adenine with Thymine, Guanine with Cytosine. This pairing represents the apparent/shadow duality.

A ↔ T (2 hydrogen bonds)
G ↔ C (3 hydrogen bonds)

Each base has its complement.
Each strand has its partner.
[1 = -1]

Chirality: Right-Handed Helix

DNA (in its common B-form) is right-handed. The tetrahelix can be left or right-handed. Why did life choose right?

The answer involves the chirality of the sugar-phosphate backbone. L-amino acids and D-sugars dominate biology, creating a consistent handedness throughout molecular machinery.

This is chirality selection - one of the silent fourth becomes expressed, the other remains silent. The choice was made once, early in life's history, and propagated ever since.

DNA Helicase: The Molecular Motor

DNA helicase is an enzyme that unwinds the double helix during replication and transcription. It is a molecular motor that rotates at approximately 10,000 RPM.

DNA Helicase

DNA helicase - a hexameric ring motor that unwinds the double helix

The Hexameric Ring

Most DNA helicases form a ring of six subunits - a hexamer. This is not random. The hexamer is geometrically optimal.

Hexameric Ring Motor

Top view of a hexameric ring motor - six subunits with 60° symmetry

Subunits

6

Hexameric structure

Angle

60°

360°/6 per subunit

Symmetry

C6

Six-fold rotational

60° = 30κ

6 × 60° = 360° (complete rotation)

60° is the internal angle of an equilateral triangle.
Six triangles tile a plane → hexagonal symmetry.

The Apparent Speed Paradox

Here is where our geometric derivation connects to the macroscopic world. DNA helicase demonstrates the exact same paradox we see in vinyl records, gears, and propellers.

💿

Vinyl Record

Outer edge faster than center

Gears

Same at contact point

🧬

DNA Helicase

Radial velocity gradient

At 10,000 RPM (167 Hz), the angular velocity is constant: ω = 1047 rad/s

But linear velocity varies with radius: v = ω × r

Speed at Different Radii

Location Radius Linear Velocity
Central pore 6.5 Å 6,806 Å/s
Mid-ring 25 Å 26,175 Å/s
Outer edge 50 Å 52,350 Å/s

The DNA passing through the central pore moves at a different speed than the outer edge of the helicase ring. Same rotation, different speeds. The geometry cannot lie.

Unwinding Rates

Helicase Type Rate (bp/s) Conditions
E. coli DnaB 35 - 500 In vitro / In vivo
T7 gp4 ~130 Optimal
Human MCM 15 - 30 Cell cycle dependent
Viral helicases 100 - 300 Variable

The κ-Limited Rate

Can we predict unwinding rates from geometry?

Rate_max = (1/κ) × step_size = 28.65 × 6 bp ≈ 172 bp/s

This theoretical limit from κ matches observed rates remarkably well. The T7 helicase at 130 bp/s is ~76% of this limit - close to our coupling constant (5/24 ≈ 21% loss expected).

Universal Molecular Motors

DNA helicase is not unique. Across biology, hexameric ring motors appear again and again. The geometry that makes helicase work makes ALL rotary motors work.

DNA Unwinding

DNA helicase unwinding the double helix - the molecular motor in action

The Hexamer Family

Motor Function Ring Size Rotation Rate
DNA Helicase Unwind DNA Hexamer (6) ~167 Hz
F₁-ATPase ATP synthesis Hexamer (α₃β₃) ~130 Hz
Bacterial Flagellum Cell propulsion Ring motor ~300 Hz
Viral Portal DNA packaging Dodecamer (12) Variable
AAA+ ATPases Protein unfolding Hexamer (6) Variable

Why Hexamers Dominate

Geometric Stability

60° sectors = equilateral triangular symmetry. Maximum stability with minimum components.

Force Distribution

Six points of contact distribute mechanical load evenly around the ring.

Helix Processing

6 steps ≈ 60% of a DNA turn. Efficient for tracking helical substrates.

Protein Domains

Standard protein domain sizes fit 6x around a functional pore.

F₁-ATPase: The Smallest Motor

F₁-ATPase is the rotary motor portion of ATP synthase - the enzyme that produces most of the ATP in cells. It is the smallest known rotary motor.

Diameter

~10 nm

Nanoscale

Speed

~130 Hz

7,800 RPM

Efficiency

~100%

Near perfect

The motor rotates in 120° steps (3 per revolution) as it synthesizes ATP. Each step corresponds to one ATP molecule. The geometry is inescapable.

The Bacterial Flagellum

Bacteria swim using rotating flagella powered by molecular motors embedded in their cell membrane. These motors can spin at up to 300 Hz (18,000 RPM).

The flagellar motor is more complex than helicase - it has multiple ring components - but the fundamental principle is the same: rotary motion powered by sequential conformational changes around a ring.

The Universal Coupling

Across all these motors, we see similar efficiency limits:

coupling = σ × cos(BC) = 5/24 ≈ 0.208

This ~20% "loss" appears in:

The geometry sets the limit. The motors approach it but cannot exceed it.

"Life discovered the geometry. The geometry was always there."

DNA Geometry Calculator

Explore the geometric relationships yourself. All calculations derive from the fundamental constant κ = 2π/180.

Helicase Velocity Calculator

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DNA Turn Calculator

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κ Derivation Calculator

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Unwinding Rate Predictor

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Reference Values

Constant Value Expression
κ 0.0349066... 2π/180
κ_shadow (1/κ) 28.6478897... 180/2π
σ 0.3125 5/16
cos(BC) 0.6667... 2/3
coupling 0.2083... 5/24