Weighing twice as much as the Sun, it is the most massive neutron star measured to date. Together with a short orbital period of only 2.5 hours, the system provides insight into binary stellar evolution and the emission of gravitational radiation.
An artist’s impression of the PSR J0348+0432 binary system. The pulsar (with radio beams) is extremely compact, leading to a strong distortion of space-time (illustrated by the green mesh). The white-dwarf companion is shown in light-blue.
Science / J. Antoniadis (MPIfR)
The energy loss through this radiation has already been detected in the radio observations of the pulsar, making it a laboratory for General Relativity in extreme conditions. The findings are in excellent agreement with Einstein's theory.
Imagine half a million Earths packed into a sphere 20 kilometers in diameter, spinning faster than an industrial kitchen blender. These extreme conditions, almost unimaginable by human standards, are met in a neutron star – a type of stellar remnant formed in the aftermath of a supernova explosion. Neutron stars often catch the attention of astronomers because they offer the opportunity to test physics under unique conditions. They were first discovered almost half a century ago as pulsars which emit radio pulses like a lighthouse. Pulsar research has been honored with two Nobel prizes, one for their discovery (1974) and one for the first indirect detection of gravitational waves (1993) – a consequence of Einstein’s theory of General Relativity.
With these masses at hand, one can calculate the amount of energy taken away from the system by gravitational waves, causing the orbital period to shrink. The team immediately realized that this change in the orbital period should be visible in the radio signals of the pulsar and turned its full attention to PSR J0348+0432, using the three largest single-dish radio telescopes on Earth (Fig. 2). “Our radio observations with the Effelsberg and Arecibo telescopes were so precise that by the end of 2012 we could already measure a change in the orbital period of 8 microseconds per year, exactly what Einstein’s theory predicts”, states Paulo Freire, scientist at MPIfR. “Such measurements are so important that the European Research Council has recently funded BEACON, a new state-of-the-art system for the Effelsberg radio telescope.”In terms of gravity, PSR J0348+0432 is a truly extreme object, even compared to other pulsars which have been used in high precision tests of Einstein’s general relativity. At its surface, for example, it has a gravitational strength that is more than 300 billion times stronger than that on Earth. In the center of that pulsar, more than one billion tons of matter is squeezed into a volume of a sugar cube. These numbers nearly double the ones found in other ‘pulsar gravity labs’. In the language of general relativity, astronomers were able for the first time to precisely investigate the motion of an object with such a strong space-time curvature (see Fig. 1). “The most exciting result for us was, that general relativity still holds true for such an extreme object”, says Norbert Wex, a theoretical astrophysicist in MPIfR’s fundamental physics research group. In fact, there are alternative theories that make different predictions, and therefore are now ruled out. In this sense, PSR J0348+0432 is taking our understanding of gravity even beyond the famous ‘Double Pulsar’, J0737-3039A/B, which was voted as one of the top ten scientific breakthroughs of 2004 by the ‘Science’ journal.
BEACON: The Effelsberg observations were part of "BEACON", a 1.9-million-Euro project funded by the European Research Council aimed to push tests of gravity theories into new territories. Paulo Freire/MPIfR is the principal investigator of BEACON. The project has funded a state-of-the-art instrument to be installed at Effelsberg in the coming months that will target the pulsar with the aim to substantially improve the accuracy of the published results.Original Publication:
Norbert Junkes | Max-Planck-Institut
Further reports about: > Astronomie > Astronomy > ESO’s Very Large Telescope > Earth's magnetic field > European Research Council > Large Hadron Collider > MPIfR > Max-Planck-Institut > Mobile phone > Pulsar > Radioastronomie > Relativity > Telescope > extreme conditions > fundamental physics > general relativity > gravitational waves > neutron star > radio telescope > white dwarf
Move over, lasers: Scientists can now create holograms from neutrons, too
21.10.2016 | National Institute of Standards and Technology (NIST)
Finding the lightest superdeformed triaxial atomic nucleus
20.10.2016 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences
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...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences