The Hierarchy of Structure: Top-Down vs. Bottom-Up
For our Universe, there are basically two approaches to the theory of structure formation via gravitational instability – top-down and bottom-up. Top-down theories claim that the largest structures formed first, thereafter subdividing into clusters, groups, and galaxies. Bottom-up theories assert that the Universe’s primordial seeds formed protogalaxies and that these objects subsequently to together to form galaxies, groups, clusters, and so on.
My class looked at different processes and objects and tried to determine whether they followed top-down or bottom-up theories. Following is a list of what they found.
Formation of sand: boulder® rock ® pebble ® sand
Creating a sculpture: block of clay
Making paper: trees
Decay process: corpse® maggot ® bacteria ® protein
Buffalo wings: chicken
Composing music: score
clarinets, trumpets, trombones, violins, cellos
Formation of physical things: quarks, gluons® protons, neutrons ®
Formation of biological things: cell® multicell ® organ ® organ
Education: K-6® middle school ® high school ® college ® graduate
Computer programs: flowchart of ideas® procedures ® modules ®
Making clothes: fibers® thread ® fabric ® clothing
Kool Aid: sugar, water, powdered drink mix® kool-aid drink
Snowman: snowflakes® snow ® snowballs ® snowman
Depending on the perspective, several of these items could be made by either top-down or bottom-up processes.