Week4, In Triplet loss, what it means when ||f(A)-f(P)||2 = ||f(A)-f(N)||22

Course Q&A Deep Learning Specialization Convolutional Neural Networks
1

Hi, I really cannot understand why the equality can appear in the formula below

image
image1920×989 115 KB

what the formula means when left is equal to right .
Intuitively，it should be that left is always less than right.
Thank you.

2

Hey, as you can look in the formula, we’ve got a margin parameter called alpha, with the margin making sure that distance between anchor and positive is always less than anchor and negative. But if you’re taking the alpha as zero, you could consider equality when the case is extremely borderline perhaps where a human annotator cant even tell them apart?

3

You mean, like twins. human can not even tell them apart. it makes sense.
thanks a lot