The world line of a large body . . . is formed of innumerable smaller world lines. . . . Here and there these fine threads enter and leave the tapestry whose threads are the world lines of atoms. . . . As we move timeward along the tapestry, its various threads forever shift about in space and so change their places relative to one another. . . . (Jeans, Mysterious Universe 125-26)There is as much movement in any page of Joyce's book. In Finnegans Wake also images and verbal motifs are in constant motion, shifting around, transforming into one another, disappearing only to reappear in a new form. Joyce devoted much of his time to expanding the scope of his book by searching for supporting elements in a variety of sources and incorporating them into the text. These sources were not only extremely varied, but, for Joyce, they also enjoyed equal status: a nursery rhyme was as good as the Bible and a joke as good as a fact. By blending diverse elements, Joyce tried to recreate reality in all its infinite richness and complexity. He was not interested in any one view of reality; instead he tried to show how a multi-level reality constitutes itself in the mind to form our individual perception of the world. In the mind a variety of impulses constituting intuitive and rational processes are in constant interaction, through which they create a singular, unique experience of reality.
In its reliance on the reader's participation to create the meaning of the text, Finnegans Wake resembles the concept of the probability wave in quantum physics. According to wave mechanics, a scientific description of reality at its most basic level does not consist of certain knowledge about events but rather of probabilities of their occurrence. These probabilities, suspended half way between being and not being, express only a "tendency to exist." To give the reality a definite form, the scientist must actively participate in his experiment, unavoidably influencing the outcome by his choice of the experimental procedures. The transformation of the probability wave into certainty in the course of a subatomic experiment parallels and resembles the very act of reading Finnegans Wake. Here the complexity, richness and indefinite character of the text itself preclude a definite interpretation of its meaning. The book does, however, achieve a definite status as the text is read and its elements, fused with the reader's own mental images and processes, form a dynamic continuum of its own.
Finnegans Wake thus supports Bohr's principle of complementarity. Quantum physics explains that the notion of undulatory and corpuscular properties of light is not disturbing once we realize that physics does not study the universe but rather our knowledge about the universe. The two properties express not the nature of light itself but rather that of our interaction with light. Similarly, Finnegans Wake describes not so much the world itself as our ideas about it and the expression of those ideas in language. The recurrent motif of the letter represents not only the world's literature and, in the broadest sense of the word, human knowledge, but also Finnegans Wake itself. The book comments extensively on the difficulties involved in attempts to interpret univocally the meaning of the text and, by extension, of the universe which it attempts to describe.
These characteristics of Finnegans Wake do not mean that Joyce's purpose was to recreate in his book the concept of the universe introduced by relativity and quantum physics. They do, however, point to a multiplicity of similarities between new physics and the universe of Finnegans Wake. Joyce's willingness to incorporate the elements of relativity and quanta into his work reflects the convergence of his world view and the new scientific concept of the world. New physics redefined the meaning of science and of the scientific method of pursuing our knowledge of reality. It replaced classical objectivity, with modern subjectivity, probability and doubt. It also showed that science is intimately connected with philosophy and cannot progress without recourse to its methods. In the light of these changes Joyce can be called not only a philosopher but a scientific writer as well.