THIS STORY HAS BEEN FORMATTED FOR EASY PRINTING
Ask Dr. Knowledge

If two pennies are not identical, then what about two atoms of hydrogen?

September 24, 2007

E-mail this article

Invalid E-mail address
Invalid E-mail address

Sending your article

Your article has been sent.

Text size +

This is actually a really cool and subtle question. As you point out, two pennies are almost certainly not quite the same - they'll have slightly different weights and shapes. Even if they were made identical, handling would corrode each one differently and the two pennies would ultimately have characteristics that make them different. (Full article: 364 words)

This article is available in our archives:

Globe Subscribers

FREE for subscribers

Subscribers to the Boston Globe get unlimited access to our archives.

Not a subscriber?

Non-Subscribers

Purchase an electronic copy of the full article. Learn More

  • $4.95 1 article
  • $9.95 4 articles
  • $25.95 Monthly