> Full-text translation from Chinese. The original remains authoritative for its research claims; this translation is not independent mathematical verification.

# Perfect Cuboid TIFV Research Notes for This Round

**Date:** 2026-10-06  
**Research line:** Perfect Cuboid / Trajectory-Information Freedom Verification  
**Status:** Research Notes / Non-proof  
**Context:** Neo.K / EveMissLab

---

## 1. Starting Point of This Round

The initial idea of this round was to use the geometric unfolding degrees of freedom of perfect rectangles or Perfect Cuboids, comparing them with circles, spheres or similar closed structures formed from distances to the center, to search for their overlapping intersection domain.

The preliminary intuition was that:

$$
\Gamma_{\mathrm{metric}}
$$

and:

$$
\Gamma_{\mathrm{unfold}}
$$

should, for genuinely closed candidates, agree, coincide or have a relationship allowing them to lift to the same geometric entity.

An early version considered "a perfect square combined with subtraction", but this was quickly recognized as liable to degenerate into an algebraic restatement of existing Pythagorean identities. The focus therefore shifted to **complete trajectory information**.

---

## 2. First Negative Result: Merely Forming a Circle Has No Discriminative Power

For any two-dimensional rectangle, the radius from its center to a vertex is:

$$
R^2
=
\left(\frac a2\right)^2
+
\left(\frac b2\right)^2.
$$

Rigid rotation naturally gives the circle:

$$
x^2+y^2=R^2.
$$

But this holds for ordinary rectangles and even any fixed vector.

The first important negative result is therefore:

$$
\boxed{
\text{ordinary rotational closure has no discriminative power}
}.
$$

This rules out the mistaken route of "seeing circular closure means seeing a new invariant".

---

## 3. Second Result: Radius Comparison Only Degenerates Back to Pythagorean Conditions

Comparing the trajectory radius with a candidate diagonal allows one to define:

$$
\Delta_{ab}
=
a^2+b^2-d_{ab}^2.
$$

For example, for a $3$-$4$-$5$ rectangle:

$$
\Delta_{34}=3^2+4^2-5^2=0.
$$

This test is correct but gives no new information, since it merely represents the Pythagorean condition as equality of two radii.

The second methodological limitation is therefore:

> If a trajectory invariant immediately reduces to an existing square equation, it can serve only as a sanity check, not as a new obstruction.

---

## 4. Euler brick sanity check

Take:

$$
(a,b,c)=(44,117,240).
$$

The three local face channels all close:

$$
44^2+117^2=125^2,
$$

$$
44^2+240^2=244^2,
$$

$$
117^2+240^2=267^2.
$$

But the global body-diagonal channel is:

$$
44^2+117^2+240^2=73225,
$$

and:

$$
73225=5^2\cdot29\cdot101.
$$

Thus, one can write:

$$
\sigma_{ab}
=
\sigma_{ac}
=
\sigma_{bc}
=1,
$$

but:

$$
\sigma_{abc}
=[2929]
\neq1.
$$

This example shows:

$$
\boxed{
\text{local closure}
\centernot\Rightarrow
\text{global closure}
}.
$$

It is still not a new Perfect Cuboid theorem, but is well suited to testing whether TIFV correctly distinguishes local and global levels.

---

## 5. Key Turning Point: The Question Concerns Information Trajectories, Not Just Trajectories

The most important conceptual correction in this round is:

> The information genuinely supplied by geometric unfolding need not lie at its starting and ending points; it may instead lie in the complete unfolding process itself.

Traditional mathematical representations often compress objects into:

$$
F(X)=0.
$$

whereas dynamic world-model-based observation sees:

$$
X_0
\rightarrow
X_1
\rightarrow
\cdots
\rightarrow
X_n.
$$

If only:

$$
X_0
$$

and:

$$
X_n,
$$

are retained, all intermediate intersections, recombinations, channel switches and information transport may disappear.

Therefore, use a lifted space:

$$
\widetilde{\mathcal M}
$$

with a projection:

$$
\pi:\widetilde{\mathcal M}\rightarrow\mathcal M.
$$

The actual research object becomes:

$$
\widetilde\gamma:[0,1]\rightarrow\widetilde{\mathcal M}.
$$

---

## 6. Path dependence

There may be two trajectories:

$$
\widetilde\gamma_1,
\qquad
\widetilde\gamma_2
$$

whose traditional projections have the same starting and ending points:

$$
\pi(\widetilde\gamma_1(0))
=
\pi(\widetilde\gamma_2(0)),
$$

$$
\pi(\widetilde\gamma_1(1))
=
\pi(\widetilde\gamma_2(1)),
$$

but whose path signatures still differ:

$$
S(\widetilde\gamma_1)
\neq
S(\widetilde\gamma_2).
$$

Finding such a signature within Perfect Cuboid structure would mean that path information genuinely extends beyond the direct expression of traditional pointwise variables.

---

## 7. Candidate Path Functionals

This round proposes the simplest general form:

$$
I[\widetilde\gamma]
=
\int_{\widetilde\gamma}\omega.
$$

If:

$$
\omega=df,
$$

the information degenerates into:

$$
f(\widetilde\gamma(1))-f(\widetilde\gamma(0)).
$$

Such a quantity gives no new information gain on closed paths.

The next phase should therefore prioritize nontrivial structures that may satisfy:

$$
\oint_{\widetilde\gamma}\omega\neq0
$$

or other path functionals not reducible to endpoint differences.

---

## 8. Candidate Holonomy

If a complete unfolding consists of a sequence of transformations:

$$
T_1,T_2,\ldots,T_n,
$$

define:

$$
H_\Gamma
=
T_nT_{n-1}\cdots T_1.
$$

Even when the spatial position satisfies:

$$
\gamma(0)=\gamma(1),
$$

one may still have:

$$
H_\Gamma\neq I.
$$

This means:

> Position has closed, but the information state has not.

This is one of the candidate obstruction forms from this round most worth further experimentation.

---

## 9. An Expanded Understanding of the "Intersection Domain"

The original geometric intuition was the intersection of two circles or two spaces.

This round develops it into a common-lift problem.

If two information observations are:

$$
\mathcal I_1
=
\Pi_1(\widetilde\Gamma),
$$

$$
\mathcal I_2
=
\Pi_2(\widetilde\Gamma),
$$

the actual common intersection domain is:

$$
\Pi_1^{-1}(\mathcal I_1)
\cap
\Pi_2^{-1}(\mathcal I_2).
$$

The final question is therefore not merely:

$$
\Gamma_1\cap\Gamma_2\neq\varnothing,
$$

but whether there exists a single:

$$
\widetilde\Gamma
$$

capable of projecting simultaneously to all necessary local, global and arithmetic structures.

---

## 10. The Role of Computer Simulation

This round establishes that computer simulation is well suited to the first phase, since it can directly preserve:

$$
X(t_0),X(t_1),\ldots,X(t_N)
$$

and, at every step:

$$
T_t,
\qquad
C_t,
\qquad
I_t.
$$

This makes it possible to observe:

- Which information splits after unfolding;
- Which information merges again;
- Where local trajectories form common intersections;
- Which defects appear only after a global closed loop;
- Which quantities are merely restatements of existing equations.

The reasonable workflow is therefore:

$$
\text{simulation discovery}
\rightarrow
\text{candidate invariant}
\rightarrow
\text{exact formalization}
\rightarrow
\text{proof or rejection}.
$$

---

## 11. Three Main Pitfall-Avoidance Conditions from This Round

### 11.1 Trivial Closure Is Not a New Invariant

A rigid body circling its center and returning to its original position cannot serve as a new discriminator.

### 11.2 Quantities Immediately Reducible to Pythagorean Conditions Are Not New Obstructions

For example, merely comparing a trajectory radius with a diagonal can serve only as a sanity check.

### 11.3 Preserve Process Information Until Safe Elimination Has Been Established

Do not project the complete dynamic state into a small set of static variables before knowing which path information is meaningful.

---

## 12. Provisional Interface with the Existing Research Main Line

The existing Perfect Cuboid research main line already contains extensive exact arithmetic, elliptic quotients, covers, square-value gates and finite-prime information.

TIFV does not compete with these; it hypothesizes that they may all be different projections of the same higher-dimensional global structure.

The provisional unifying question is whether:

$$
\exists\,\widetilde\Gamma
\quad\text{s.t.}\quad
\pi_i(\widetilde\Gamma)=\Gamma_i
$$

holds.

If it does not, one may have:

$$
\Delta_\Gamma\neq0.
$$

The long-term aim is to investigate whether:

$$
\Delta_{\mathrm{arith}}
\longleftrightarrow
\Delta_\Gamma
$$

has a formalizable correspondence.

---

## 13. What This Round Has Not Obtained

This round has not obtained:

- A proof of existence or nonexistence of a Perfect Cuboid;
- A new arithmetic theorem;
- A strict equivalence between arithmetic defects and trajectory defects;
- A holonomy invariant proved to be nontrivial;
- A path functional proved not to arise by elimination from existing equations.

The current status therefore remains: **methodological discovery and candidate-invariant design.**

---

## 14. Where to Resume Directly Next Time

If this line is reopened in the future, begin directly with the following questions without repeating this round:

### Question A

What is the minimal lifted state for the Perfect Cuboid?

$$
\widetilde{\mathcal M}_{\min}=?
$$

### Question B

Which nontrivial unfolding operations should act as generators?

$$
\{T_1,\ldots,T_m\}=?
$$

### Question C

Can two valid trajectories be found with identical endpoint projections but different path signatures?

$$
S(\widetilde\gamma_1)
\neq
S(\widetilde\gamma_2)?
$$

### Question D

Does there exist, in either of the following forms, a quantity that admits exact-arithmetic formulation and is not immediately reducible to the original Pythagorean conditions:

$$
H_\Gamma
$$

or:

$$
I[\Gamma]?
$$

### Question E

Can an existing square defect be viewed as the projection of a higher-dimensional global closure defect?

---

## 15. Conclusion of This Round

The central idea that survives this round is not "verify a Perfect Cuboid using circles", but:

$$
\boxed{
\text{Static Constraints}
\rightarrow
\text{Lifted Freedom Expansion}
\rightarrow
\text{Information Trajectory}
\rightarrow
\text{Global Closure Test}
}.
$$

and the following research principle:

> **Preserve the complete information trajectory first, then decide what information can be eliminated. If the geometric world is compressed into endpoint equations first, global information existing only during unfolding may disappear before research even begins.**
