Encoding syntactic objects and Merge operations in function spaces
Matilde Marcolli, Robert C. Berwick
TL;DR
This work tackles the challenge of realizing the core syntactic operation Merge in a neurocomputationally plausible way by embedding lexical items, encoded as functions (e.g., wavelets), into a common function space and extending this embedding to cover arbitrary syntactic objects. The authors build a nonassociative commutative magma representation using a thermodynamic semiring based on the second Rényi entropy, ensuring that Merge’s algebraic structure is preserved in the target space and that the embedding is faithful (reconstructible from the image). They prove faithfulness under a finite leaf-size bound and use topological transversality to argue generic injectivity, while addressing repetitions via a Fulton–MacPherson-type configuration space. The paper then connects this algebraic framework to neural realizations via phase synchronization, showing how Merge can be implemented as entropy-optimized cross-frequency synchronization of sinusoidal waves, and discusses the relation to existing neurolinguistic models (Martin and Murphy). The results provide a constructive, theory-guided blueprint for neurocomputational realizations of the core syntax, with a clear path toward integrating algebraic structure, Hopf-algebra dynamics on workspaces, and synchronization-based neural substrates.
Abstract
We provide a mathematical argument showing that, given a representation of lexical items as functions (wavelets, for instance) in some function space, it is possible to construct a faithful representation of arbitrary syntactic objects in the same function space. This space can be endowed with a commutative non-associative semiring structure built using the second Renyi entropy. The resulting representation of syntactic objects is compatible with the magma structure. The resulting set of functions is an algebra over an operad, where the operations in the operad model circuits that transform the input wave forms into a combined output that encodes the syntactic structure. The action of Merge on workspaces is faithfully implemented as action on these circuits, through a coproduct and a Hopf algebra Markov chain. The results obtained here provide a constructive argument showing the theoretical possibility of a neurocomputational realization of the core computational structure of syntax. We also present a particular case of this general construction where this type of realization of Merge is implemented as a cross frequency phase synchronization on sinusoidal waves. This also shows that Merge can be expressed in terms of the successor function of a semiring, thus clarifying the well known observation of its similarities with the successor function of arithmetic.
