Describing vectors in n dimensions

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Nano-Passion
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Recall that A can be broken up into its components x,y, and z. Can You simply add more components to describe any number of dimensions. Where n would be nth dimension?

A=A_x+ A_y+A_z+⋯A_n
 
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What's the square symbol for? And why do you have theoretical physics degree in your status thingy? Do you mean you will someday hope to get such a degree? I'm hoping of doing a theoretical phd someday. I didn't know there was such a thing as a purely theoretical undergraduate degree, if that's what youre talking about?

About the question: If we have a vector A, then it can be written (in some basis) as its components (A1,A2,A3,A4) For a four-dimensional vector, so yeah, there are as many components as there are dimensions.
 
BruceW said:
What's the square symbol for? And why do you have theoretical physics degree in your status thingy? Do you mean you will someday hope to get such a degree? I'm hoping of doing a theoretical phd someday. I didn't know there was such a thing as a purely theoretical undergraduate degree, if that's what youre talking about?

About the question: If we have a vector A, then it can be written (in some basis) as its components (A1,A2,A3,A4) For a four-dimensional vector, so yeah, there are as many components as there are dimensions.

For PhD I wrote what I'm striving for. Perhaps that isn't what I should do. :devil: I'll edit it.

I've only begun my third semester. :)

Edit: What square symbol?
 
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BruceW said:
A=A_x+ A_y+A_z+⋯A_n
The symbol ⋯ just before A_n it looks like two horizontal lines..

Oh sorry, that is supposed to be an ellipse (...) that indicates the sequence.
 
You don't write it that way. The components are relative to a basis as Bruce mentioned. A vector can be represented as a linear combination of components relative to said basis vectors so it would be written compactly as [itex]V = V^{\alpha }\vec{e}_{\alpha }[/itex] where the repeated indices imply summation over all possible values the index can take. So, for example, a vector [itex]V \in \mathbb{R}^{n}[/itex] can be written, when equipped with the Cartesian chart, as [itex]V = V^{x}\vec{e_{x}} + ... + V^{n}\vec{e_{n}}[/itex] where [itex]\vec{e_{x}} = (1, 0, ..., 0)[/itex] and similarly for the other basis vectors.
 
WannabeNewton said:
You don't write it that way. The components are relative to a basis as Bruce mentioned. A vector can be represented as a linear combination of components relative to said basis vectors so it would be written compactly as [itex]V = V^{\alpha }\vec{e}_{\alpha }[/itex] where the repeated indices imply summation over all possible values the index can take. So, for example, a vector [itex]V \in \mathbb{R}^{n}[/itex] can be written, when equipped with the Cartesian chart, as [itex]V = V^{x}\vec{e_{x}} + ... + V^{n}\vec{e_{n}}[/itex] where [itex]\vec{e_{x}} = (1, 0, ..., 0)[/itex] and similarly for the other basis vectors.

I have to admit, I am not familiar with that notation. But I will mention that my book stated [itex]A=A_x\widehat{i}+A_y\widehat{j}+A_z\widehat{k}[/itex]. Which is why I simply put:

[itex]A=A_x\widehat{i}+A_y\widehat{j}+A_z\widehat{k}+...A_n\widehat{t}[/itex]
 
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Nano-Passion said:
I have to admit, I am not familiar with that notation. But I will mention that my book stated [itex]A=A_x\widehat{i}+A_y\widehat{j}+A_z\widehat{k}[/itex]. Which is why I simply put:

[itex]A=A_x\widehat{i}+A_y\widehat{j}+A_z\widehat{k}+...A_n\widehat{t}[/itex]

No that is perfectly correct. It just wasn't in your original post is all.