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Shep

Why is the octopus here

Also I believe you can take a cross product in 4D, but there's no way of determining which of the other 2 directions it points in.

coolbreeze

I think there could be cross product in higher dimension. This is related to how we define cross product. For example. In a 4D space, we can take three vectors and generate a vector which is orthogonal to those three vectors. If we only want two vectors, as this is a 'product' between two vectors, then there should be only the 3D version.

haotingl

Because our physical space is in 3d and it is very difficult for us human to imagine a 4d space

notme

A different right hand rule that I had learned in a class is instead of the fingers, you curl your right hand from u to v and stick your thumb up, and your thumb will point towards uxv. This helps me when I mess the fingers up.

mateib

Why is the octopus here

The poor guy has no right hand :(

I think there could be cross product in higher dimension. This is related to how we define cross product. For example. In a 4D space, we can take three vectors and generate a vector which is orthogonal to those three vectors. If we only want two vectors, as this is a 'product' between two vectors, then there should be only the 3D version.

Would it be possible to obtain these via a similar algorithm to the determinant one for the 3d cross product?

alexz2

I believe that we can compute the value for cross product for 3D or above, but it loses the geometric meaning

achekuri

My thought is that while the cross product can be taken in higher dimensions, semantically it means nothing in geometry and also it requires more vectors maybe? Like 4d cross product requires 3 vectors?

Kevinzzz

It's the only way to visualize cross product(in my opinion

atomicapple0

cute octopus

bokangw

For 2d there is no vector's direction orthogonal to both vector