A potential problem and a magic solution
		• If we map the input vectors into a very high-dimensional feature space, surely the task of finding the maximum- margin separator becomes computationally intractable? – The mathematics is all linear, which is good, but the vectors have a huge number of components. – So taking the scalar product of two vectors is very expensive. • The way to keep things tractable is to use “the kernel trick” • The kernel trick makes your brain hurt when you first learn about it, but its actually very simple.