“Attempts to calculate the Hoyle state have been unsuccessful since 1954,” said Professor Dr. Ulf-G. Meißner (Helmholtz-Institut für Strahlen- und Kernphysik der Universität Bonn). “But now, we have done it!” The Hoyle state is an energy-rich form of the carbon nucleus.
It is the mountain pass over which all roads from one valley to the next lead: From the three nuclei of helium gas to the much larger carbon nucleus. This fusion reaction takes place in the hot interior of heavy stars. If the Hoyle state did not exist, only very little carbon or other higher elements such as oxygen, nitrogen and iron could have formed. Without this type of carbon nucleus, life probably also would not have been possible.
The search for the “slave transmitter”
The Hoyle state had been verified by experiments as early as 1954, but calculating it always failed. For this form of carbon consists of only three, very loosely linked helium nuclei - more of a cloudy diffuse carbon nucleus. And it does not occur individually, only together with other forms of carbon. “This is as if you wanted to analyze a radio signal whose main transmitter and several slave transmitters are interfering with each other,” explained Prof. Dr. Evgeny Epelbaum (Institute of Theoretical Physics II at Ruhr-Universität Bochum). The main transmitter is the stable carbon nucleus from which humans - among others - are made. “But we are interested in one of the unstable, energy-rich carbon nuclei; so we have to separate the weaker radio transmitter somehow from the dominant signal by means of a noise filter.”
What made this possible was a new, improved calculating approach the researchers used that allowed calculating the forces between several nuclear particles more precisely than ever. And in JUGENE, the supercomputer at Forschungszentrum Jülich, a suitable tool was found. It took JUGENE almost a week of calculating. The results matched the experimental data so well that the researchers can be certain that they have indeed calculated the Hoyle state.
More about how the Universe came into existence
“Now we can analyze this exciting and essential form of the carbon nucleus in every detail,” explained Prof. Meißner. “We will determine how big it is, and what its structure is. And it also means that we can now take a very close look at the entire chain of how elements are formed.”
In future, this may even allow answering philosophical questions using science. For decades, the Hoyle state was a prime example for the theory that natural constants must have precisely their experimentally determined values, and not any different ones, since otherwise we would not be here to observe the Universe (the anthropic principle). “For the Hoyle state this means that it must have exactly the amount of energy it has, or else, we would not exist,” said Prof. Meißner. “Now we can calculate whether - in a changed world with other parameters - the Hoyle state would indeed have a different energy when comparing the mass of three helium nuclei.” If this is so, this would confirm the anthropic principle.
The study was jointly conducted by the University of Bonn, Ruhr-Universität Bochum, North Carolina State University, and Forschungszentrum Jülich.E. Epelbaum, H. Krebs, D. Lee, Ulf-G. Meißner, Ab initio calculation of the Hoyle state, Physical Review Letters, 2011.
First results of NSTX-U research operations
26.10.2016 | DOE/Princeton Plasma Physics Laboratory
Scientists discover particles similar to Majorana fermions
25.10.2016 | Chinese Academy of Sciences Headquarters
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
27.10.2016 | Life Sciences
27.10.2016 | Life Sciences
27.10.2016 | Power and Electrical Engineering