Magnet levitation at your fingertips

A. K. Geim (), M. D. Simon, M. I. Boamfa and L. O. Heflinger
Additional contact information
A. K. Geim: High Field Magnet Laboratory, University of Nijmegen
M. D. Simon: University of California at Los Angeles
M. I. Boamfa: High Field Magnet Laboratory, University of Nijmegen
L. O. Heflinger: University of California at Los Angeles

Nature, 1999, vol. 400, issue 6742, 323-324

Abstract: Abstract The stable levitation of magnets is forbidden by Earnshaw's theorem, which states that no stationary object made of magnets in a fixed configuration can be held in stable equilibrium by any combination of static magnetic or gravitational forces1,2,3. Earnshaw's theorem can be viewed as a consequence of the Maxwell equations, which do not allow the magnitude of a magnetic field in a free space to possess a maximum, as required for stable equilibrium. Diamagnets (which respond to magnetic fields with mild repulsion) are known to flout the theorem, as their negative susceptibility results in the requirement of a minimum rather than a maximum in the field's magnitude2,3,4. Nevertheless, levitation of a magnet without using superconductors is widely thought to be impossible. We find that the stable levitation of a magnet can be achieved using the feeble diamagnetism of materials that are normally perceived as being non-magnetic, so that even human fingers can keep a magnet hovering in mid-air without touching it.

Date: 1999
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/22444 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:400:y:1999:i:6742:d:10.1038_22444

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/22444

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().