What is the Distribution of the Sum of Two Standard Brownian Motions?

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B(t) is a standard Brownian Motion. u and v are both => 0. What is the distribution of B(u) + B(v)?

The mean is 0.

For the variance I get Var(B(u)+B(v)) = u+v. Is this right?
 
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BrownianMan said:
B(t) is a standard Brownian Motion. u and v are both => 0. What is the distribution of B(u) + B(v)?

The mean is 0.

For the variance I get Var(B(u)+B(v)) = u+v. Is this right?

How did you get this?
 
Aren't B(u) and B(v) independent? If so, then the variance of their sum should be the sum of their variance.
 
BrownianMan said:
Aren't B(u) and B(v) independent? If so, then the variance of their sum should be the sum of their variance.

Is ##\text{Var}( B(1) + B(1))## equal to 2? Is ##2^2## equal to 2?
 
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