Community and its Analogy

Reading Block's book on community, when he mentioned the need to understand the fabric of community, I started to relate this to the fabric of the universe and how the gravitational pull of large cosmic objects will pull and affect other smaller objects much like how the our sun pulls together the 8 planets to orbit around it. This is because the gravity of the sun shapes the fabric of space into a curvature that forms the orbits that the planets travel on. The sun also nourishes the planets around it and most successfully on earth. So a community of practice is somewhat similar to the solar system where its members interact with each other peripherally from a safe distance, pulling and pushing each other through ones gravity of influence while all the time orbiting in a predictable manner around the core interest of the sun which undoubtedly provide the strongest gravitational pull. Thus, nurturing the 'nuclear force of the sun' is vital for the health and the continuous existence of the 'solar' community of practice. What is this force in terms of a community of practice or a collaborative practice?