Perfect Spheres: A Theoretical Possibility or an Impossibility?

  • Context: Undergrad 
  • Thread starter Thread starter kolleamm
  • Start date Start date
  • Tags Tags
    Spheres
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
3 replies · 5K views
kolleamm
Messages
476
Reaction score
44
I've been wondering about this for a while. If you were to take a perfect sphere and cut it in half so that you would see a circle and then use a magnifying glass to zoom in closer and closer on part of the circle, the arc would approach near flatness but it would never reach it so therefore since an arc is constantly changing it cannot be fully defined therefore perfect spheres cannot exist in the real world. What do you think?
 
Physics news on Phys.org
Agree.

World's Roundest Object!:
 
kolleamm said:
If you were to take a perfect sphere and cut it in half so that you would see a circle and then use a magnifying glass to zoom in closer and closer on part of the circle, the arc would approach near flatness but it would never reach it so therefore since an arc is constantly changing it cannot be fully defined therefore perfect spheres cannot exist in the real world. What do you think?

That is incorrect. The arc of a circle is easily "defined" using several different equations. A perfect sphere cannot exist in real life mainly because matter is made up of atoms, which put a limit on how smooth and accurate the surface can be. It will never be perfectly round.
 
  • Like
Likes   Reactions: kolleamm, atom jana and billy_joule
Thanks everyone for the replies