Dynamic Tango

The basis for the workshop have been laid out thorough the experience of “La fisica in ballo”, the interactive workshop presented by Giovanni Filocamo and Marco Gheri during the 2005 Genoa Science Festival.

The concept of point is easily associated with that of center of gravity, the point where one can imagine to be contained the whole weight of a person, for instance. When we stand the projection of the center of gravity falls in the surface comprised within our feet, in the same way two dancers have to define a ‘common ground’ where the center of gravity of the couple can fall. During the workshop the audience is involved in games and experiments with various objects and their bodies in order to identify the different centers of gravity.

Geometry 2 _ the lineThe workshop’s aim regarding this particular subject is to explain and explore the transmission lines. The rules of Argentine Tango state that the man leads the steps and the woman has to follow them, for this particular reason the communication between the dancers is fundamental and must therefore be efficient. The marcas (leads) of the man start from his torso and must reach the feet of the woman in order to achieve that efficiency, this is only possible when the dancers maintain a perfect frontality and in particular when the woman is able to respond to the marcas with the necessary rapidity, regaining a mirror-like position with the man. In short, the lead of the man will be efficient if the transmission lines between the dancers, that is to say, the embrace and their arms, are efficient. During the workshop these concepts are described and illustrated with the use of different springs and the concept of elastic constant is introduced.

Geometry 3 _ the plane

The plane is an important feature of Argentine Tango since the dancers must move on an imaginary plane at all times. This means that their centers of gravity or, as tango teachers often exemplify, their heads shouldn’t rise and fall continuously (as in the Viennese waltz for instance), rather they should effect moves which develop, as far as possible, along a plane. This technique enables the dancers to move perpendicularly respect the direction of the weight force, thus making less work in the movements and making the dance more elegant, smooth and the movements quicker.
In order to experience this aspect of the dancing technique the participants to the workshop are asked to walk under a rigid plane (made of Plexiglas), the better their walk is, the less bumps their heads will sustain during the experiments.

Movement 1 _ the friction, the origin of movement

In the second part of the workshop the focus will be on dynamics. The first topic will be the friction as the fundamental element of walking; the public will be able to experience different types of friction, dragging their feet on different materials. In this case he friction both hampers and allows the movement, at first blocks the advancing of the feet, then it allows them a grip on the floor so that the step can actually be taken.

Movement 2 _ translations

The movement of any rigid body can easily be summarized in a translation of his center of gravity and an eventual rotation around one or more of his axis. These are the (simplified) terms of a well-known Physics theorem.
During the workshop will be addressed two types of movements from the point of view of a tango dancer, of course.
In tango, the translation corresponds to every walking moves. For it to be correct it is necessary to apply all the previously explained concept and techniques. The public will be able to experiment a simple tango walk, this time in couples, with further explanations and examples of the correct dancing technique.

Movement 3 _ rotations

Rotations represent the natural continuation of what has been illustrated in the previous section of the workshop. Again in this part is stressed the importance of an erect posture in connection with the theorem of the conservation of angular momentum. The examples in this case vary from tango dancing to ice-skating, in particular the so-called spins of ice-skaters. The experiment involves, in this case, a swivel chair and a brave voluntary assistant who sits on the chair and, while it is rotating, opens and closes his or her legs and arms in order increase or diminish the speed of the rotation.
The experiment is repeated with tango dancing, showing the public, and making them try, how rotations (giros) in tango can vary in type and intensity depending on the proximity of the dancers and on their speed.