Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Rick Autry on 06/04/2009 21:30:03
-
Rick Autry asked the Naked Scientists:
I'd like to see some kind of experiment to demonstrate the nature of the "soliton", and how to make the phenomenon visible to us visually oriented creatures...
What do you think?
-
Rick Autry asked the Naked Scientists:
I'd like to see some kind of experiment to demonstrate the nature of the "soliton", and how to make the phenomenon visible to us visually oriented creatures...
What do you think?
Duhhhhh, so what in the world is a "soliton"?
-
They used to market a little gadget you could use to make them. It looked like a cylinder about eight inches in diameter. You placed one end of it into the water of a swimming pool and quickly pulled a handle on the other end. This caused a little circular swirl of water that would last a minute or so and remain intact as it moved across the pool.
-
Duhhhhh, so what in the world is a "soliton"?
This from Wiki:
Definition
A single, consensus definition of a soliton is difficult to find. Drazin and Johnson (1989) ascribe 3 properties to solitons:
1. They are of permanent form;
2. They are localised within a region;
3. They can interact with other solitons, and emerge from the collision unchanged, except for a phase shift.
More formal definitions exist, but they require substantial mathematics. Moreover, some scientists use the term soliton for phenomena that do not quite have these three properties (for instance, the 'light bullets' of nonlinear optics are often called solitons despite losing energy during interaction).
-
Rick Autry asked the Naked Scientists:
I'd like to see some kind of experiment to demonstrate the nature of the "soliton", and how to make the phenomenon visible to us visually oriented creatures...
What do you think?
http://lie.math.brocku.ca/~sanco/solitons/solitonkdv3.html
http://www.usf.uni-osnabrueck.de/~kbrauer/solitons/soli1.html
http://www.ma.hw.ac.uk/~chris/scott_russell.html
-
Rick Autry asked the Naked Scientists:
I'd like to see some kind of experiment to demonstrate the nature of the "soliton", and how to make the phenomenon visible to us visually oriented creatures...
What do you think?
I personally visualize solitons as being the wave of waves... it's weird really. They can exist below the threshold of Planck Scales, and yet, below these scales without resorting to string theory, shouldn't have any mass... but hey, they're weird things.
-
Solitary waves are an important part of physics and the fundamental particles that we know and love can be thought of as persistant solitary waves of energy this is is in some respect ehat string theory is all about. One of the things missing from the pictures given is that in most media these waves bust have a long term average value of zero so if there is a single sharp spike there is a large small diffuse negative period around the wave.
-
Here is an example of how to create (http://www22.pair.com/csdc/car/carfre10.htm) a soliton in your backyard pool.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww22.pair.com%2Fcsdc%2Fcar%2Ffalaco4.jpg&hash=4413784bf53b3db0670f9a0c2356b198)
Falaco Solitons are exhibitions of topological defects in a discontinuity surface.
[ Kiehn 1986]. The phenomena is easily reproduced by placing a half-submerged circular disc (a Frisbee) in a swimming pool, then stroking the plate slowly in the direction of its oblate axis. At the end of the stroke extract the plate from the water, imparting kinetic energy and distributed angular momentum, to the fluid in the form of a pair of Rankine Vortices. In a few seconds, in bright sunlight, the concave Rankine depressions, with visible spiral arm caustics, will decay into a pair of convex dimples of negative Gauss curvature, which can be observed via their Snell projections as black spots on the bottom of the pool. In a few tries you will become an expert experimentalist, for the spots will persist for many minutes in a still pool.