# Are there any naturally occuring non-embedded manifolds?

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## Can all manifolds be embedded?

The strong Whitney embedding theorem states that any smooth real m-dimensional manifold (required also to be Hausdorff and second-countable) can be smoothly embedded in the real 2m-space (R2m), if m > 0.

## Can all manifolds be embedded in Euclidean space?

Every smooth manifold has a embedding of smooth manifolds into a Euclidean space ℝk of some dimension k.

## Is the Earth a manifold?

Locally, the surface of the Earth looks like a 2-dimensional plane, so it is a 2-manifold.

## Why are manifolds called manifolds?

The term “manifold” comes from German Mannigfaltigkeit, by Riemann. In English, “manifold” refers to spaces with a differentiable or topological structure, while “variety” refers to spaces with an algebraic structure, as in algebraic varieties.

## What is embedded manifold?

An embedded submanifold (also called a regular submanifold), is an immersed submanifold for which the inclusion map is a topological embedding. That is, the submanifold topology on S is the same as the subspace topology.

## What is Whitney’s Theorem?

Whitney’s theorem [4] asserts that any edge isomorphism of a finite connected graph of cardinality greater than four is induced by a vertex isomorphism. In his monograph on graphs [2], Ore proposed the extension of this theorem to infinite graphs.

## Is spacetime a manifold?

General. A spacetime is a manifold that models space and time in physics. This is formalized by saying that a spacetime is a smooth Lorentzian space (X,μ) equipped with a time orientation (see there). Hence a point in a spacetime is called an event.

## How many types of manifolds are there?

Manifold types. There are four types of manifolds — direct connect, coplanar, traditional, and conventional.

## What manifold is the universe?

It is more likely that the universe is one of the 10 orientable Euclidean 3-manifolds. The simplest orientable, compact, Euclidean 3-manifold is the 3-torus. It is a generalization of the torus in a higher dimension.

## Is submanifold a manifold?

Loosely speaking, a manifold is a topological space which locally looks like a vector space. Similarly, a submanifold is a subset of a manifold which locally looks like a subspace of an Euclidian space.

## Is a manifold with boundary a manifold?

A manifold with boundary is a manifold with an edge. For example, a sheet of paper is a 2-manifold with a 1-dimensional boundary. The boundary of an n-manifold with boundary is an (n−1)-manifold. A disk (circle plus interior) is a 2-manifold with boundary.

## What is canonical embedding?

In many cases of interest there is a standard (or “canonical”) embedding, like those of the natural numbers in the integers, the integers in the rational numbers, the rational numbers in the real numbers, and the real numbers in the complex numbers.

## Why is embed important?

Embeddings make it easier to do machine learning on large inputs like sparse vectors representing words. Ideally, an embedding captures some of the semantics of the input by placing semantically similar inputs close together in the embedding space. An embedding can be learned and reused across models.

## Which is correct imbed or embed?

For anyone looking for quick information, let’s state this right from the start: there is no difference between imbed and embed. They are just different spellings of the same word; there’s no difference in their meaning, and they are both completely correct to use.

## What is an imbedding in topology?

In mathematics, an embedding (or imbedding) is one instance of some mathematical structure contained within another instance, such as a group that is a subgroup. When some object X is said to be embedded in another object Y, the embedding is given by some injective and structure-preserving map f : X → Y.

## What is allow embedding?

Allowing embedding means that people can re-publish your video on their website, blog, or channel, which will help you gain even more exposure. But you want full credit for your video, of course! Make sure you specify that publishers credit your video every time it is used.

## What is the embedding space?

Embedding space is the space in which the data is embedded after dimensionality reduction. Its dimensionality is typically lower that than of the ambient space. Manifold Learning.