- #351
matt grime
Science Advisor
Homework Helper
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so |R| is in your opinion simultaneously any of n^aleph-0, for any n in N?
Seeing as you are doing arithemic on cardinals, must not |R|=|R|?
thus mustn't 2^aleph-0 = 3^aleph-0 =...?
Otherwise |R| is not equal to |R|.
As for the other questions you raise.
you write that |Q| =|N| trivially because of the counting algorithm you give.
But I can give a counting algorithm that shows |N| is equal to the cardinality of the even natural numbers - the counting goes n <--->2n
Since YOU have said the evens have cardinality aleph0/2, it must then follow if your arithemetic is correct that aleph0 =|N|=|even naturals|=aleph0/2
that is logically what you are claming if you think |Q|=|N|.
And no cardinality does not depend on what the elements in a set are, even in the finite case. I have 4 oranges, I have 4 apples, it's the same 4 in each case.
Who says that the real numbers ARE a line? They are not a line - they are, in one construction, the set of equivalence classes of cauchy sequences of rational numbers. That they are useful for measuring and drawing a line is not important. sqrt -1 is useful in electrical engineering, that doesn't mean it is a voltage or a current.
I've read page 5. It is not correct in showing |Q|=|N| as the correspondence sends both 1/3 and 3 to the same element in N, so it isn't a bijection.
Seeing as you are doing arithemic on cardinals, must not |R|=|R|?
thus mustn't 2^aleph-0 = 3^aleph-0 =...?
Otherwise |R| is not equal to |R|.
As for the other questions you raise.
you write that |Q| =|N| trivially because of the counting algorithm you give.
But I can give a counting algorithm that shows |N| is equal to the cardinality of the even natural numbers - the counting goes n <--->2n
Since YOU have said the evens have cardinality aleph0/2, it must then follow if your arithemetic is correct that aleph0 =|N|=|even naturals|=aleph0/2
that is logically what you are claming if you think |Q|=|N|.
And no cardinality does not depend on what the elements in a set are, even in the finite case. I have 4 oranges, I have 4 apples, it's the same 4 in each case.
Who says that the real numbers ARE a line? They are not a line - they are, in one construction, the set of equivalence classes of cauchy sequences of rational numbers. That they are useful for measuring and drawing a line is not important. sqrt -1 is useful in electrical engineering, that doesn't mean it is a voltage or a current.
I've read page 5. It is not correct in showing |Q|=|N| as the correspondence sends both 1/3 and 3 to the same element in N, so it isn't a bijection.