Hello Scrum community
Scrum Guide says "The Product Backlog is an ordered list of everything that is known to be needed in the product."
"The Product Backlog lists all features, functions, requirements, enhancements, and fixes that constitute the changes to be made to the product in future releases."
Given this definition there could be no Spike in the backlog according to Scrum, is it right?
Should I evaluate different frameworks and build different prototypes (some of them could be thrown away), how could a Product Owner manage this need?