Tag Archives: ucsc

How dense is a neutron star?

These celestial bodies have some peculiar statistics. For example if you were able to take Mount Everest and cram it into your morning cup of coffee you’d achieve the same density as a neutron star.

The reason why these stars are so dense is because they form from the collapse of a star. The way a star keeps its shape is through chemical reactions such as the conversion of hydrogen atoms bonding to create helium. When these bonds occur they produce an outward force in the form of heat. This force is stronger than gravity and keeps the star from caving in.

One of the outcomes when a star runs out of its energy is that it explodes into a supernova and leaves behind a highly dense remnant the size of the San Francisco Bay which becomes a neutron star.

Watch the full video with Enrico Ramirez-Ruiz at UC Santa Cruz:

Where do heavy elements like gold come from?

During the formation of the solar system Earth underwent an event known as the late bombardment. This was a time of a high amount of asteroid collisions hitting the Earth’s surface. These objects painted the surface of our planet with heavy elements such as gold, silver and titanium.

But how did these asteroids form and where do they come from? Scientists still don’t know the full answer to this question. The issue here is that even our Sun can only produce up to a certain level of heavy materials. Star power works because atoms of hydrogen combine to form helium, but the size and density of most stars can only produce Iron until they lose power and collapse.

One theory is that the biggest stars in our universe live these short lifespans. When they die they explode and produce these very dense stars known as neutron stars. The explosion itself is known as a supernovae and in this event it is thought that there is enough heat to produce heavy elements.

However even with this scenario, the computer models are not completely conclusive and so Enrico Ramirez-Ruiz at UC Santa Cruz has been developing alternative theories.

The Science of Music and Algorithms


“I can understand why it’s an issue if you’ve got an extremely romanticized view of what art is,” he says. “But Bach peed, and he shat, and he had a lot of kids. We’re all just people.”

– David Cope, UC Santa Cruz, emeritus professor

“To some extent, this match is a defense of the whole human race. Computers play such a huge role in society. They are everywhere. But there is a frontier they must not cross. They must not cross into the area of human creativity. It would threaten the existence of human control in such areas as arts, literature, and music.”

So said Gary Kasparov, chess grandmaster, one year before he lost to Deep Blue, IBM’s chess-playing supercomputer. Meanwhile, a relatively anonymous professor of music in California had created a computer program capable of composing pieces of music in the style of great composers that most people could not differentiate from authentic compositions. The professor, David Cope, named this program Experiments in Musical Intelligence, or “Emmy”. Since then, Cope and his successive programs have been the objects of both celebration and scorn, challenging the world’s perception of what musical creativity entails.

Cope’s argument, and the basis for his software, is that creativity is essentially recombinant: consciously or not, all composers plagiarize their progenitors and contemporaries. What makes his (or Emmy’s) work superior to the stilted and awkward compositions of earlier programs are two fundamental insights into the syntax of music. Rather than rely on the traditional divisions of musical notation, Cope developed an analytic musical syntax that goes into what Douglas Hofstadter (of Gödel, Escher, Bach) terms the “tension-resolution status” of a piece, the two forces that underlie all music. Secondly, though the program composes according to formal rules, it also uses heuristics that allow it to sometimes ‘break’ its own rules in innovative ways.

Alex Tesar (Source Art & Science Journal)

More stories can be found here.