# doubt

Joined Sep 29, 2008
19
hi guys
while solving problems in laplace transforms we usually substitute s=jω but actually s=σ+jω why are we neglecting σ here?
what is its significance?

#### darenw5

Joined Feb 2, 2008
45
A particular example might help with getting a clear crisp answer, but generally, that sigma helps make an the integral converge. The result doesn't depend on the value of sigma; like limits in beginning calculus, you can't just throw in zero, but approach it carefully. I hope that makes sense...

#### Ratch

Joined Mar 20, 2007
1,070