Posted on 06/06/2008 2:23:34 PM PDT by 668 - Neighbor of the Beast
LONDON: Scot physicists have found a way to make objects float in the air without any physical support, something that is known as the levitation effect.
Professor Ulf Leonhardt and Dr Thomas Philbin of the University of St Andrews say that the "incredible levitation effects" can be achieved by reversing the Casimir force, which normally causes objects to stick together...
(Excerpt) Read more at timesofindia.indiatimes.com ...
Casimir effectIn physics, the Casimir effect and the Casimir-Polder force are physical forces arising from a quantized field. The typical example is of two uncharged metallic plates in a vacuum, placed a few micrometers apart, without any external electromagnetic field. In a classical description, the lack of an external field also means that there is no field between the plates, and no force would be measured between them. When this field is instead studied using quantum mechanics, it is seen that the plates do affect the virtual photons which constitute the field, and generate a net force[1]either an attraction or a repulsion depending on the specific arrangement of the two plates. This force has been measured, and is a striking example of an effect purely due to second quantization. [2] [3] (However, the treatment of boundary conditions in these calculations has led to some controversy.[4])
Dutch physicists Hendrik B. G. Casimir and Dirk Polder first proposed the existence of the force and formulated an experiment to detect it in 1948 while participating in research at Philips Research Labs. The classic form of the experiment, described above, successfully demonstrated the force to within 15% of the value predicted by the theory.[5]
Because the strength of the force falls off rapidly with distance, it is only measurable when the distance between the objects is extremely small. On a submicrometre scale, this force becomes so strong that it becomes the dominant force between uncharged conductors. In fact, at separations of 10 nmabout 100 times the typical size of an atomthe Casimir effect produces the equivalent of 1 atmosphere of pressure (101.3 kPa).
Although the Casimir effect can be expressed in terms of virtual particles interacting with the objects, it is best described and more easily calculated in terms of the zero-point energy of a quantized field in the intervening space between the objects. In modern theoretical physics, the Casimir effect plays an important role in the chiral bag model of the nucleon; and in applied physics, it is becoming increasingly important in the development of the ever-smaller, miniaturised components of emerging microtechnologies and nanotechnologies.
Darn sure wasn't covered in any physics course I ever took, at least not that i can remember.
Oops, you got there first, sorry...
No problem. It’s a hot lazy Saturday afternoon. I’m just lazing around they keyboard waiting for Global Cooling to resume.
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