what is the dimension of the vector space of real numbers over the field of rational numbers? and why?
jasim v
2006-10-19 09:12:22 UTC
what is the dimension of the vector space of real numbers over the field of rational numbers? and why?
Four answers:
just another math guy
2006-10-19 10:23:34 UTC
The real numbers are uncountable. The rational numbers are countable. It is a fact that the direct sum of countable sets is countable, so the real numbers cannot be a countable direct sum of copies of the rational numbers. That is to say, the real numbers have uncountably infinite degree over the rational numbers.
brittany
2016-11-24 00:29:11 UTC
rational numbers algebraic numbers (over the rationals) p-adic numbers fields of finite characteristic those are possibly the main undemanding edit: specific, Q^3 is a vector area over the rational numbers. R and R^3 are additionally vector areas over the rational numbers (in spite of the undeniable fact that countless-dimensional). that's accomplished by way of figuring out a vector in R^3 with the three approximating sequences of rational numbers for each element
Eulercrosser
2006-10-19 09:24:30 UTC
All finite extensions are algebraic. Since R/Q is not algebraic, it is not finite.
Another way to see this:
If you were to add the √p for all prime p to Q, you would not get all of R, but would create an infinite extension. Therefore, even the algebraic closure of Q intersect R is infinite over Q.
anonymous
2006-10-19 10:27:46 UTC
infinity,
since you need an infinite number of generators,
as many as the irrational numbers (not all)
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