Researchers in Israel and the US have achieved an energy breakthrough through a study that concluded that melting quarks have the capability of generating 10 times more energy than nuclear fusion.
The findings are the result of a study by Tel Aviv University physics Prof. Marek Karliner, and Prof. Jonathan L. Rosner of the University of Chicago. Quarks are one of the elementary particles in physics and considered to be the most basic building blocks of matter in Universe. While protons and neutrons have long been considered as building blocks of matter, it is quarks that make up protons and neutrons.
Quarks are unique for they are able to hold fractional electrical charge unlike protons and electrons that hold complete charge i.e. +1 or -1. There’s not one, but six types of quarks, but physicists usually refer to them in terms of three pairs: up/down, charm/strange, and top/bottom. Quarks join together to form composite particles called hadrons. The most stable of these are protons and neutrons, the components of atomic nuclei.
For quite some time now scientists have been wondering if it was possible to create fusion reaction from quarks. It turns out that just a few months ago physicists at the CERN particle accelerator near Geneva discovered a new type of particle called a baryon, which contains two heavy quarks of the kind called a “charm” and a “light quark.”
Scientists explain that because the mass of the particles involved before and after melting is known, they are in a position to calculate the amount of energy emitted precisely by Einstein’s famous E = mc2 formula. The calculation showed that the amount of energy emitted between two baryons with a “charm” quark is 12 million electron volts, similar to that emitted by nuclear fusion between two heavy isotopes of hydrogen.
The precise measurement of the particle of the two “charm” quarks allows them to simulate for the first time a process of fusion at the quark level and calculate its results.
The perfect liquid — now even more perfect
How liquid can a fluid be? This is a question particle physicists at the Vienna University of Technology have been working on. The “most perfect liquid” is nothing like water, but the extremely hot quark-gluon-plasma which is produced in heavy-ion collisions at the Large Hadron Collider at CERN. New theoretical results at Vienna UT show that this quark-gluon plasma could be even less viscous than was deemed possible by previous theories. The results were published in Physical Review Letters and highlighted as an “editors’ selection”.
Liquids and their Viscosity
Highly viscous liquids (such as honey) are thick and have strong internal friction, quantum liquids, such as super fluid helium can exhibit extremely low viscosity. In 2004, theorists claimed that quantum theory provided a lower bound for viscosity of fluids. Applying methods from string theory, the lowest possible ratio of viscosity to the entropy density was predicted to be ħ/4π (with the Planck-constant ħ). Even super fluid helium is far above this threshold. In 2005, measurements showed that quark-gluon-plasma exhibits a viscosity just barely above this limit. However, this record for low viscosity can still be broken, claims Dominik Steineder from the Institute for Theoretical Physics at Vienna UT. He obtained this remarkable result working as a PhD-student with Professor Anton Rebhan.
Black Holes and Particle Collisions
The viscosity of a quark-gluon plasma cannot be calculated directly. Its behavior is so complicated that very sophisticated methods have to be applied, says Anton Rebhan: “Using string theory, the quantum field theory of quark-gluon plasma can be related to the physics of black holes in higher dimensions. So we are solving equations from string theory and then transfer the results to the physics of the quark-gluon plasma.” The previously established lower bound for viscosity was calculated in a very similar way. However, in these calculations the plasma was modeled to be symmetric and isotropic. “In fact, a plasma produced by a collision in a particle accelerator is not isotropic at the beginning”, says Anton Rebhan. The particles are accelerated and collided along one specific direction – so the resulting plasma shows different properties, depending on the direction from which one looks at it.
Breaking the Limits
The physicists at Vienna UT found a way to include this anisotropy in their equations – and surprisingly the limit for the viscosity can be broken in this new model. “The viscosity depends on several other physical parameters, but it can be lower than the number previously considered to be the absolute lower bound”, Dominik Steineder explains. The on-going quark-gluon-experiments at CERN will provide opportunities for testing the new theoretical predictions.