you use a memory bank where you have a buffer of previous embeddings and then you just use that buffer as your negatives so for that buffer to function well it needs to be reasonably historically average version of your current encoder so that it can contrast well if it's just your current encoder then the previous embedding stored in the buffer or not rather than anymore so that basically so the idea for moko where you basically take an original image oh and you split it into queries in keys which is the two different