Physlib

Physlib.ClassicalMechanics.HarmonicOscillator.Geometric.Basic

Configuration space of the harmonic oscillator

i. Overview

The configuration space `Q` of the one-dimensional harmonic oscillator is the space of possible positions of the oscillator, formalised here as a one-dimensional smooth manifold.

`Q` carries a single chosen global coordinate, modeled by `EuclideanSpace ℝ (Fin 1)`. This coordinate supplies the topology and the smooth-manifold structure through a single global chart.

The global coordinate also identifies each tangent space with the same Euclidean model. The map `tangentCoord q` records the coordinate representative of a tangent vector at `q`; this tangent-coordinate infrastructure is used by later geometric constructions on the oscillator.

ii. Key results

- `ConfigurationSpace` : the configuration manifold `Q` of the harmonic oscillator, wrapping the chosen `EuclideanSpace ℝ (Fin 1)` coordinate. - `ConfigurationSpace.valEquiv` : the coordinate equivalence identifying `Q` with its `EuclideanSpace ℝ (Fin 1)` model. - `ConfigurationSpace.valHomeomorphism` : the global coordinate homeomorphism underlying the manifold chart. - `ConfigurationSpace.valDiffeomorph` : the global coordinate chart as an analytic diffeomorphism, upgrading `valHomeomorphism` to a smooth identification of `Q` with its model. - the `ChartedSpace` and `IsManifold` instances, exhibiting `Q` as a one-dimensional analytic manifold modeled on `EuclideanSpace ℝ (Fin 1)`. - `tangentCoord` : the chart-induced continuous linear equivalence from the tangent space at a configuration to `EuclideanSpace ℝ (Fin 1)`. - `instNormedAddCommGroupTangent` and `instNormedSpaceTangent` : the normed real vector-space structure on tangent spaces, supplied through the global coordinate model. - `instFiniteDimensionalTangent` : finite-dimensionality of each tangent space, transported through `tangentCoord`. - `ConfigurationSpace.toSpace` : the point of physical `Space 1` determined by a configuration.

iii. Table of contents

  • A. The configuration space type
  • B. Topology and coordinate homeomorphism
  • C. Smooth manifold structure
  • D. The coordinate diffeomorphism
  • E. Tangent-coordinate infrastructure
  • F. Map to physical space

iv. References

- Ivo Terek, Introductory Variational Calculus on Manifolds, page 1 (Section 1, Basic definitions and examples).

A. The configuration space type

`ConfigurationSpace` wraps a single chosen global coordinate valued in `EuclideanSpace ℝ (Fin 1)`. We record extensionality in this coordinate together with a function-like coordinate access mirroring that of `EuclideanSpace ℝ (Fin 1)`.

B. Topology and coordinate homeomorphism

`ConfigurationSpace` carries the topology induced by its chosen coordinate `ConfigurationSpace.val`: a set of configurations is open exactly when it is the preimage of an open set under `val`. The wrapper/unwrapper pair is the coordinate equivalence `valEquiv`, which is a homeomorphism `valHomeomorphism` for this induced topology — its continuity in both directions is just the universal property of the induced topology. We transport Hausdorffness and second countability across it from the model space, so `Q` is a well-behaved topological manifold.

C. Smooth manifold structure

`ConfigurationSpace` is an analytic manifold modeled on `EuclideanSpace ℝ (Fin 1)`, via the single global chart `valHomeomorphism`. With one chart the only coordinate change is the chart's self-transition, which is analytic, so chart compatibility is immediate.

D. The coordinate diffeomorphism

The single global chart is an analytic diffeomorphism, not merely a homeomorphism, so `Q` is identified with its `EuclideanSpace ℝ (Fin 1)` model as a smooth manifold. With one chart this is immediate: the only transition is the analytic self-transition already recorded in the manifold structure. This smooth identification is what lets smoothness of maps to or from `Q` be tested in the chosen global coordinate, the device used for trajectories and their velocities.

E. Tangent-coordinate infrastructure

The global coordinate on `ConfigurationSpace` also gives a coordinate representative for tangent vectors. The tangent spaces inherit their normed real vector-space structure from the Euclidean coordinate model, and `tangentCoord q` records the resulting continuous linear equivalence.

F. Map to physical space

The point of one-dimensional physical `Space 1` determined by a configuration, obtained by reading off the underlying coordinate. This links the abstract configuration manifold to the concrete coordinate model.

12 declarations

theorem

x(i)=x.val(i)x(i) = x.\text{val}(i) for configurations in QQ

Let QQ denote the configuration space of the one-dimensional harmonic oscillator, which is modeled on the Euclidean space E1\mathbb{E}^1 (represented as `EuclideanSpace ℝ (Fin 1)`). For any configuration xQx \in Q and index iFin 1i \in \text{Fin } 1, the value obtained by treating xx as a function applied to ii is equal to the ii-th component of its underlying global coordinate vector x.valx.\text{val}.

instance

Topological space structure on the configuration space QQ

The configuration space QQ of the harmonic oscillator is endowed with the topological structure induced by the coordinate map val:QR1\text{val} : Q \to \mathbb{R}^1 (where R1\mathbb{R}^1 is represented by EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)). This topology is defined such that a subset UQU \subseteq Q is open if and only if it is the preimage of an open set in the Euclidean model space R1\mathbb{R}^1 under the map val\text{val}.

definition

Coordinate equivalence QE1Q \simeq \mathbb{E}^1

This definition establishes a coordinate equivalence (a bijection) between the configuration space QQ of the one-dimensional harmonic oscillator and its model space E1\mathbb{E}^1 (represented as `EuclideanSpace ℝ (Fin 1)`). The map sends a configuration xQx \in Q to its underlying coordinate value x.valE1x.\text{val} \in \mathbb{E}^1, with an inverse that wraps a coordinate vector back into a configuration point.

instance

The configuration space QQ is a Hausdorff space

The configuration space QQ of the one-dimensional harmonic oscillator is a Hausdorff space (also known as a T2T_2 space). This topological property is transported from the Euclidean model space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)) via the global coordinate homeomorphism.

instance

The configuration space QQ is second-countable

The configuration space QQ of the one-dimensional harmonic oscillator is second-countable. This property is inherited from the Euclidean model space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)) via the coordinate homeomorphism.

instance

Charted space structure on the configuration space QQ modeled on R1\mathbb{R}^1

The configuration space QQ of the one-dimensional harmonic oscillator is equipped with a charted space structure modeled on the Euclidean space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)). This structure is defined by an atlas containing a single global chart, which is the homeomorphism valHomeomorphism:QR1\text{valHomeomorphism} : Q \simeq \mathbb{R}^1 that maps each configuration to its corresponding coordinate value.

instance

The Configuration Space QQ is an Analytic Manifold Modeled on R1\mathbb{R}^1

The configuration space QQ of the one-dimensional harmonic oscillator is an analytic manifold (of class CωC^\omega) modeled on the 1-dimensional Euclidean space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)) with the standard identity model with corners I(R,R1)\mathcal{I}(\mathbb{R}, \mathbb{R}^1). This manifold structure is established via a single global coordinate chart.

definition

Analytic diffeomorphism QR1Q \simeq \mathbb{R}^1

The map `valDiffeomorph` is an analytic diffeomorphism (of class CωC^\omega) between the configuration space QQ and its model Euclidean space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)). This global coordinate chart upgrades the underlying coordinate homeomorphism to a smooth identification of the configuration manifold QQ with its model space R1\mathbb{R}^1.

instance

Normed additive commutative group structure on the tangent space TqQT_q Q

For any configuration qq in the configuration space QQ of the one-dimensional harmonic oscillator, the tangent space TqQT_q Q is endowed with the structure of a normed additive commutative group. This structure is induced by the model space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)).

instance

Normed real vector space structure on the tangent space TqQT_q Q

For any configuration qq in the configuration space QQ of the one-dimensional harmonic oscillator, the tangent space TqQT_q Q is endowed with the structure of a normed vector space over R\mathbb{R}. This structure is induced by the model space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)).

definition

Continuous linear equivalence between TqQT_q Q and R1\mathbb{R}^1

For any configuration qq in the configuration space QQ of the one-dimensional harmonic oscillator, tangentCoord(q)\text{tangentCoord}(q) is the continuous linear equivalence between the tangent space TqQT_q Q and the Euclidean model space R1\mathbb{R}^1 (represented as EuclideanSpace R(Fin 1)\text{EuclideanSpace } \mathbb{R} (\text{Fin } 1)). This identification is induced by the manifold's global coordinate chart.

instance

Tangent Spaces of the Configuration Space QQ are Finite-Dimensional

For any configuration qq in the configuration space QQ of the one-dimensional harmonic oscillator, the tangent space TqQT_q Q (associated with the smooth manifold structure modeled on R1\mathbb{R}^1) is a finite-dimensional vector space over R\mathbb{R}.