Are Algebraic Extensions Always Finite?

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Hurkyl said:
How? Can you come up with an example?

The dot notation is definitely not always compatible with field notation, as I will show. Consider the field Z/3Z. Writing 5*2 is absurd because 5 is not an element of the field Z/3Z. You need to write [itex]5 \cdot 2[/itex] if you want to represent the sum [itex]2+2+2+2+2[/itex].

morphism, if you are saying that if F is a field that contains f, then [itex]n \cdot f = nf[/itex] WHEN the characteristic of F is greater than n or equal to 0, then I think that is true.
 
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ehrenfest said:
Writing 5*2 is absurd because 5 is not an element of the field Z/3Z.[/itex]
Er, yes it is. 5 denotes the same element that 2 does.
 
OK. This is getting really technical. I would rather move on.