This article deals with the importance of the shape of vacuum despite its lack of material. The Casimir force that arises from quantum fluctuations in the vacuum between surfaces depends critically on their shape at the nanoscale.
The Effect of the Casimir Force
Two opposing plates attract each other in the vacuum. This astonishing phenomenon is known as the Casimir effect, named after the Dutch physicist Hendrik Casimir who discovered it in 1948. It is a quantum mechanical effect that arises because the perfect vacuum is not completely empty but is filled with countless fluctuations in the electromagnetic field, imposed by the Heisenberg uncertainty principle, giving the vacuum non-zero energy. The two plates provide boundaries where some electromagnetic fluctuations can exist compared to those in the unbounded vacuum outside the plates. Therefore, the energy of the vacuum between the plates is different from that outside, leading to the “Casimir” force, which varies with the fourth power of the inverse distance between the plates and depends on their surface area, making it, in precise terms, a pressure. In a study published in Physical Review Letters, Chan et al. discovered that the exact shape of the plates also has an effect by measuring the Casimir force between a gold-coated sphere and a nanosilicon surface.
Conclusion
In summary, the shape of the vacuum is significant despite its lack of material. The Casimir force that arises from quantum fluctuations in the vacuum between surfaces depends critically on their shape at the nanoscale.
References
The references include the following research and studies:
- Casimir, H. B. G. Proc. K. Ned. Akad. Wet. 51, 793–795 (1948).
- Chan, H. B. et al. Phys. Rev. Lett. 101, 030401 (2008).
- Buks, E. & Roukes, M. L. Europhys. Lett. 54, 220–226 (2001).
- Chan, H. B., Aksyuk, V. A., Kleiman, R. N., Bishop, D. J. & Capasso, F. Science 291, 1941–1944 (2001).
- Chen, F., Mohideen, U., Klimchitskaya, G. L. & Mostepanenko, V. M. Phys. Rev. Lett. 88, 101801 (2002).
- Krause, D. E., Decca, R. S., López, D. & Fischbach, E. Phys. Rev. Lett. 98, 050403 (2007).
- Lamoreaux, S. K. Phys. Rev. Lett. 78, 5–8 (1997).
- Mohideen, U. & Roy, A. Phys. Rev. Lett. 81, 4549–4552 (1998).
- Büscher, R. & Emig, T. Phys. Rev. A 69, 062101 (2004).
- Lambrecht, A. & Marachevsky, V. N. preprint at http://arxiv.org/abs/0806.3142 (2008).
- Rodrigues, R. B., Maia Neto, P. A., Lambrecht, A. & Reynaud, S. Phys. Rev. A 75, 062108 (2007).
Author information
Astrid Lambrecht at Laboratoire Kastler Brossel, Campus Jussieu, Case 74, 75252 Paris Cedex 05, France.
This article was published in Nature on August 13, 2008.
Journal number: 454
Article pages: 836-837
Citation number: 454836a
Publication date: August 13, 2008
Issue date: August 14, 2008
Article link: https://doi.org/10.1038/454836a
Leave a Reply