[Excerpt] – The Somerville Redevelopment Authority (SRA) took by eminent domain 3.99 acres of land from Cobble Hill Center LLC (Cobble Hill) as a demonstration project under G. L. c. 121B, § 46 (f). The issue presented is whether the broad eminent domain powers granted to redevelopment authorities by G. L. c. 121B, § 11 (d), include demonstration projects under § 46 (f). Relying on the express language of the statute, we conclude that they do. We further define “demonstration” in accordance with its plain meaning and general use as requiring the test or development of a different, new, or improved means or method. We conclude that the demonstration project plan at issue — designed to “serve as a model, innovative approach to community development that combines a public use [a new public safety facility] successfully integrated with private development” and public transit to eliminate blight — satisfies this definition for the purposes of § 46 (f). Finally, we conclude that takings satisfying the requirements of § 46 (f) are constitutional.