MHB How is √2 μ Interpreted Geometrically?

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The discussion focuses on interpreting the measure √2 μ geometrically in the context of real analysis. The measure μ is defined as the unique positive regular measure on B(R^2) that relates to Riemann integrals, specifically stating that λf equals the integral of f with respect to μ. It is suggested that understanding this measure can be simplified by considering a basic function, such as f=1, which represents area computation. The measure √2 μ effectively scales the area by a factor of √2, indicating a geometric transformation. This highlights the relationship between measures and geometric interpretations in integration.
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This is part 2 of a question... I already solved part 1 but I can't seem to be able to solve this one.
Interpret the measure √2 μ geometrically?

Any ideas... This is from real analysis class

Thanks in advance!
 
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Re: Measure... Geometrically?

Juliayaho said:
This is part 2 of a question... I already solved part 1 but I can't seem to be able to solve this one.
Interpret the measure √2 μ geometrically?

Any ideas... This is from real analysis class

Thanks in advance!

What is [math]\displaystyle \mu [/math] representing?
 
Re: Measure... Geometrically?

The unique positive regular measure on B(R^2) such that for all f in C_c(R^2) λf= ∫_R^2 f dµ

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Prove It said:
What is [math]\displaystyle \mu [/math] representing?

The unique positive regular measure on B(R^2) such that for all f in C_c(R^2) λf= ∫_R^2 f dµ

- - - Updated - - -

Juliayaho said:
The unique positive regular measure on B(R^2) such that for all f in C_c(R^2) λf= ∫_R^2 f dµ

- - - Updated - - -
The unique positive regular measure on B(R^2) such that for all f in C_c(R^2) λf= ∫_R^2 f dµ

λf=∫(from R to Riemann) f(tt)dt for all f in C_c(R^2).
 
Re: Measure... Geometrically?

I could be wrong, but it seems to me that this question could be answered much more easily (that is, intuitively) by thinking about the corresponding Riemann integral. It's a fact that if the function is Riemann integrable, then
$$\int_{ \mathbb{R}^{2}} f \, dA = \int_{ \mathbb{R}^{2}} f \, d\mu.$$
So take an example, and make $f$ really simple, say $f=1$. Then your integral is simply computing area. Your new measure, $\sqrt{2} \mu$, simply multiplies your area by $\sqrt{2}$, since constants pull out of integrals (at least, they pull out of Riemann and Lebesgue integrals). What is going on geometrically for that to happen?
 
We all know the definition of n-dimensional topological manifold uses open sets and homeomorphisms onto the image as open set in ##\mathbb R^n##. It should be possible to reformulate the definition of n-dimensional topological manifold using closed sets on the manifold's topology and on ##\mathbb R^n## ? I'm positive for this. Perhaps the definition of smooth manifold would be problematic, though.

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