representation right so what people have done is they have included so-called negative samples where you'll say I'll take a different image from you know from this dataset but it's a different image than this image and I also do some maybe some data augmentation with that image and then I send this through the same encoder to also give me an H so this is the H let's call that H original this is H plus because it's the same image but slightly differently augmented and this is H minus which is a different image