Q: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
One challenge to the traditional concept of matter as tangible "stuff" came with the rise of field physics in the 19th century. Relativity shows that matter and energy (including the spatially distributed energy of fields) are interchangeable. This enables the ontological view that energy is prima materia and matter is one of its forms. On the other hand, the Standard Model of Particle physics uses quantum field theory to describe all interactions. On this view it could be said that fields are prima materia and the energy is a property of the field.
A:
Relativity illustrates that what is interchangeable?