About the HEHI Logo

The HEHI logo takes it's origin in the crest of old Niels Bohr himself. When he recieved the Order of the Elephant he, as is custumary, had to choose a crest. At that time, he had formulated the motto Opposites are Complimentary and he there for chose the Ying-Yang symbol as the base of his crest. The crest is shown to the right. It hangs in the church of Frederiksborg Slot. The motto enscribed over the Ying-Yang says in Latin Contraria Sunt Complimenta.

Contraria Sunt Complimenta
So what does this have to do with the HEHI logo? Well, the HEHI logo is formed by taking the classical Ying-Yang symbol, as shown to the right. Ying-Yang
The Ying and the Yang is then separated to symbolise two incoming colliding heavy ions. The dots of opposite colour suggests a quark in one of the nucleons in the colliding nuclei. Ying & Yang
Now, as the Ying and the Yang represents to colliding nuclei, speeding towards each other with velocities close to the speed of light, the special relativity kicks in. That means, that the nuclei - that is, the Ying and the Yang - are Lorenz-contracted, as shown to the right. This represents the situation just prior to the collision. Ying & Yang - Lorenz contracted
As the two nuclei collide, the quarks and gluons in the nuclei interact. Again, due to high speeds, the quarks may actually take a rather long time to interact - so long that the two nuclei becomes physically separated. That means, that the interacting quarks may 'drag' their interaction behind them. This is illustrated by the yellow line in the final logo, as shown to the right. Ying & Yang - interacting
The colours chosen for the logo is not the same as in he original crest of Niels Bohr. Instead a bright red, blue, and yellow was chosen. These represents the 3 colour charges that exists in Quantum Chromo Dynamics - the prevailing theory on how quarks and gluons interact.
The logo is designed by Christian Holm Christensen.