This month in Physics World, Eric Linder and Saul Perlmutter, both at the University of California at Berkeley, reveal how little we know about dark energy and describe what advances in our knowledge of dark energy we can expect in the coming decade from a series of planned space missions.
Perlmutter was the leader of one of the two separate teams of astrophysicists who concluded, from watching distant supernovae, that the cosmic expansion was accelerating and not slowing under the influence of gravity, as was previously thought. The two teams' finding confirmed just how little we know about our universe.
The two teams' discovery has led to the creation of the "concordance model" of the universe, which states that 75 per cent of our universe is made up of dark energy, 21 per cent of dark matter, another substance we know little about, with only a remaining four per cent being made up of matter that we do understand. The most conventional explanation is that dark energy is some kind of "cosmological constant" that arises from empty space not being empty, but having an energy as elementary particles pop in and out of existence.
Since the first evidence for the accelerating universe was made public in early 1998, astrophysicists have provided further evidence to shore up the findings and advances in the measurement methods bode well for increasing our understanding in the future.
Galaxies and the cosmic background hold some significant clues. Equipment that can make a more robust comparison between galaxy patterns across the sky and investigate temperature fluctuations in the cosmic microwave background, helping trace the pattern of galaxy formation, is being made available. Methods for further observation of supernovae are expanding and improving too.
Eric Linder and Saul Perlmutter write, “The field of dark energy is very young and we may have a long and exciting period of exploration ahead before it matures.”
The December issue also includes reporting from Robert P Crease, historian at the Brookhaven National Laboratory, US, on the difficulty of deciding who should gain credit for the discovery of the accelerating universe and comment from Lawrence M Krauss, director of the Center for Education and Research in Cosmology and Astrophysics at Case Western Reserve University, US, on the possibility that we may never be able to tell if dark energy is a cosmological constant or something more exotic still.
Also in this issue:•50 years on: why physicists still love the computer-programming language Fortran
•Christmas books: a round-up of all the best new physics titles for the holiday period
Joseph Winters | alfa
Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory
SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences