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UIB Scientists will put Eintein's Relativity Theory to the test with the fastest supercomputers in Europe

It is the second time that the international team led by UIB gains access to supercomputers only used for state of the art research

29 January, 2013

SuperMUC supercomputer

An international team of researchers led by Sascha Husa, member of the UIB Relativity and Gravitation Group (UIBGRG), has been selected to access SuperMUC, the second fastest supercomputer in Europe. This computer will be used to simulate one of the most violent phenomena in the universe: black holes mergers. And which is the ultimate goal? Put Einstein's general relativity to the test under extreme conditions.

In total, the researchers will have more than 37 million computation hours (per core) for black holes simulations using SuperMUC, the second most powerful computer in Europe and the sixth in the world. This supercomputer occupies more than 20 square meters, solves over 3000 trillion operations per second and requires an electrical output of more than 3 megawatts.

The process for determining who has access to this supercomputer is very selective. However, it is the second time that the group led by the UIB is one of the selected. Very few groups are selected twice, and even less with an allocation of computing hours so high. The team led by Professor Husa consists of more than 20 experts from around the world, working in universities in the Cardiff, Vienna and Jena Universities, the Albert Einstein Institute in Potsdam and the California Institute of Technology.

Playing the "greatest hits" of the universe on supercomputers

With this supercomputer the researchers will simulate pairs of black holes that are about to merge. Just before the two black holes become one, these objects move very quickly. This warps the space (space-time) around them and these distortions are known as "gravitational waves".

In some way, we can "translate" gravitational waves into sound waves and so we can "hear" the universe's soundtrack. This project studies how exactly are gravitational waves generated during these collisions, which are one of the most intense sources of these waves.

Detecting gravitational waves is a major scientific and technological challenge since their effects are extremely tiny. This is why is so important to perform simulations, as it makes much easier to identify them among all the data collected by gravitational wave detectors. Although so far they have not been detected, we expect to be able to make the first detection with the Advanced LIGO detector.

Black hole collisions to test Relativity

Artist concept of two black holes merging

Simulations of black hole mergers are one of the phenomena of the universe in which gravity plays a fundamental role. This allows us to test Einstein's general relativity, which explains gravity in extreme conditions. If we detect gravitational waves originating from these shocks we will have one of the most important evidence that Einstein's theory is correct. Or, on the contrary, the first direct evidence that it is not.

Through this project we can also improve our understanding of the enigmatic black holes. We know that many of them are formed as a result of the death of a star in a supernova explosion. During these explosions, ater the stars run out of fuel their outer layers are expelled into space in the form of dust and gas. The remaining part implodes and forms a black hole. The dust that escaped falling into te black hole is now part of us as calcium or iron. We are stardust.

In addition, the detection of gravitational waves will provide a new way of doing astronomy. Currently, almost all we know of the universe is through the light, in its various forms. While X-rays appear to us quite different from the visible light, both are electromagnetic waves. However, gravitational waves have a completely different nature. For this reason their detection will open a new window to the cosmos that could change forever the way we understand the universe.

Cutting edge science in times of crisis

In a time when doing science is increasingly complicated, it is specially important to get access to international resources, something which in turn can only be achieved being the best in the field. Fortunately this is still the case of many Spanish research groups, such as the UIB Relativity Group.

In addition, the UIB group is also member of the international collaboration LIGO, the most important worlwide in the investigation of gravitational waves. This requires high-level scientific contributions. The UIB Relativity Group plays a major role in software development and data analysis. Thanks to this, it can access the resources of the collaboration and become involved in the discoveries to be made in the future gravitational wave detector.

The researchers at UIB are part of the national CPAN and Multidark research networks, and are the only Spanish group taking part in the LIGO project. Further simulations are performed at Mare Nostrum, Spain's leading supercomputer at the National Center for Supercomputing applications in Barcelona.