world end theory

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Across
  1. 2. many forms including thermal,mechanical,kinetic
  2. 5. the emission of energy as electromagnetic waves
  3. 6. an idea
  4. 7. the great size or extent
  5. 8. getting cold
Down
  1. 1. the whole cosmic system
  2. 3. falling down or giving way
  3. 4. enough
  4. 9. getting bigger