Stephanie JonkersEssay

What Is a Hole? A Journey Into Path-Space Geometry

A conceptual essay about compression, obstruction, and rewiring as different distortions of accessible path space.

What is a hole?

It sounds trivial at first. A hole is just empty space, a gap, a missing piece. But the more you look, the less consistent that definition becomes.

  • A donut has a hole.
  • A tunnel has a hole.
  • A crater does not.
  • A valley does not.
  • A black hole isn’t empty at all.

So what are we actually pointing at when we say “hole”?

This question led me down a rabbit hole that ended up connecting topology, dynamics, and even physics. Not through objects, but through paths.

The Shift: From Objects to Paths

Instead of asking what a hole is made of, consider this instead: how does a hole change what paths are possible?

A hole is a distortion in the space of accessible paths.

From any point in a system, whether it's a physical space, a graph, or a state-space, there are many possible paths forward. A hole changes the structure of those possibilities.

Diagram
Shift in Perspective

Drag the orbs to reshape the accessible paths through a short editorial-style excerpt.

Object viewPath view

Three Ways Path Space Can Be Distorted

1. Compression (Funnel Holes)

Some regions pull you in. Paths become concentrated, escape becomes harder, and movement can become effectively one-way.

  • a crater
  • an attractor
  • gravity
  • black holes

In these cases, the space of possible futures collapses inward.

Diagram
Compression

Paths collapse inward. Futures concentrate rather than remain evenly spread.

2. Obstruction (Topological Holes)

Some regions cannot be crossed, only circumnavigated. Paths split into distinct classes, and the distinction persists even if you deform the paths slightly.

  • a ring
  • a tunnel
  • a donut

Nothing pulls you inward here. Instead, the structure of space forces movement into different route classes.

Diagram
Obstruction

Paths split into route classes. You can go around, but not through.

3. Rewiring (Shortcut Structures)

Some structures don’t block or pull, they reconnect. Distant regions become close, new paths appear, and connectivity changes abruptly.

  • a wormhole
  • a shortcut edge in a graph

This doesn’t quite fit the traditional idea of a hole, but it clearly reshapes the space of possible paths.

Diagram
Rewiring

New connectivity appears. Distant regions become surprisingly close.

A Unified View

Instead of searching for a single definition, it becomes more useful to describe hole-like structures by how they deform accessible path space.

Hole-like structures are deformations of accessible path space.

Each one can be described by how it affects three different dimensions:

  • Compression → Do paths collapse inward?
  • Obstruction → Do paths split into distinct classes?
  • Rewiring → Does connectivity change?
Diagram
Unified Map

A simple signature for how a structure reshapes accessible path space.

SystemCompressionObstructionRewiringFlat spaceCraterAttractorRing / AnnulusWormhole
Simple signature

Σ(x, T) = (Compression, Obstruction, Rewiring)

Different systems produce different signatures: flat space stays low across the board, a crater rises on compression, a ring scores high on obstruction, and a wormhole introduces strong rewiring.

The Not So Obvious Part

The biggest realisation wasn’t finding a definition. It was:

“Hole” is not one thing.

It’s a word we’ve been using to describe different ways the future becomes constrained, sometimes by being pulled inward, sometimes by being forced around, sometimes by being rewired entirely.

Why This Matters

This perspective doesn’t replace existing theories. But it connects them.

  • Topology becomes a theory of obstruction.
  • Dynamical systems become a theory of compression.
  • Geometry and networks reveal rewiring.

Even ideas like gravity or quantum collapse can be reinterpreted, carefully, as specific distortions of path space.

What This Is (and Isn’t)

This is

  • A conceptual framework
  • A way of organising intuition
  • A bridge between different domains

This is not

  • A new physical law
  • A replacement for existing mathematics
  • A finished theory

Final Thought

What started as a simple question turned into something else entirely. Not a definition of holes, but a way of thinking about possibility.

A hole is not empty space. It is a place where the structure of what can happen next changes.