<human>:  I have a question about the work of John von neumann. What is the von Neumann bottleneck?
<bot>: The von Neumann bottleneck is a limitation on the speed of a computer that is caused by the need to perform a large number of operations. The von Neumann bottleneck is named after John von Neumann, who was a mathematician and physicist who worked on the design of the first modern computers.