In a neural network component, an input representation of dimension 512 is processed by 8 parallel 'heads'. For each head, a 'key' vector is produced by multiplying the input representation by a specific weight matrix. The dimensions of the 'key' vectors from all heads are concatenated, resulting in a final combined dimension of 512. What is the shape of the weight matrix used to produce the 'key' vector for a single head?

Determining the Number of Attention Heads

Debugging a Multi-Head Attention Layer