This article is a summary of a YouTube video "Tensors Explained Intuitively: Covariant, Contravariant, Rank" by Physics Videos by Eugene Khutoryansky

Understanding Tensors: Transforming Mathematical Objects

TLDRTensors are mathematical objects that transform when basis vectors change. They are essential for understanding the curvature of spacetime in Einstein's General Relativity.

Key insights

Tensors are fundamental for understanding the curvature of spacetime in Einstein's General Relativity.

A tensor of rank 1 is a vector.

Tensors have contra-variant and co-variant components that vary in opposite or same ways when basis vectors change.

Tensors can be described by dot products with basis vectors.

A tensor of rank 2 associates numbers with every possible combination of two basis vectors.

Q&A

What are tensors?

Tensors are mathematical objects that transform when basis vectors change. They are used to understand the curvature of spacetime in Einstein's General Relativity.

What is a tensor of rank 1?

A tensor of rank 1 is a vector that can be described by its components in terms of basis vectors.

How do tensors vary when basis vectors change?

Tensors have contra-variant and co-variant components that vary in opposite or same ways when basis vectors change. Contra-variant components decrease when basis vectors increase, while co-variant components increase.

How can tensors be described by dot products with basis vectors?

Tensors can be described by taking the dot product of the tensor with each basis vector. This reveals the magnitude of the tensor in each direction.

What is a tensor of rank 2?

A tensor of rank 2 associates numbers with every possible combination of two basis vectors. It provides a more comprehensive description of tensor interactions.

Timestamped Summary

00:03Tensors are mathematical objects that transform when basis vectors change.

00:21A tensor of rank 1 is a vector.

01:08Tensors have contra-variant and co-variant components that vary in opposite or same ways when basis vectors change.

02:35Tensors can be described by dot products with basis vectors.

05:32A tensor of rank 2 associates numbers with every possible combination of two basis vectors.