Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The search for dark matter and dark energy in the Universe

17.09.2003


Philosophical transactions a November issue

Organised and edited by Carlos Frenk, George Kalmus, Nigel Smith and Simon White

What is the universe made of? How is it expanding? What is the origin of galaxies and other cosmic large-scale structures? These questions and some tentative answers were the focus of the discussion meeting on The search for dark matter and dark energy in the Universe, held at The Royal Society on 22-23 January 2003.



Astronomers have known for many years that the predominant form of mass in the universe is dark matter, that is, matter that does not emit detectable electromagnetic radiation at any wavelength. Only recently, however, has it become possible to measure how much dark matter there is. These measurements are based on surveys of unprecedented numbers of galaxies combined with careful studies of tiny irregularities in the residual heat left over from the Big Bang, the cosmic microwave background radiation. These irregularities are imprints left in the radiation by the precursors of today’s galaxies. By contrasting the properties of the primeval irregularities with the large-scale distribution of galaxies, physicists can infer the amount of dark matter in the universe. The surprising result is that the density of dark matter falls short, by about a factor of three, from the critical value required to ensure that the cosmic expansion would eventually come to a halt.

Although we now know how much dark matter there is, its identity is still unknown. It is clear, however, that the dark matter cannot be the same sort of matter that we see in stars, planets and people. Such ordinary matter makes up only about 10 percent of the total. The search for the remaining 90 percent of the cosmic mass is intense and is taking place deep underground in well shielded laboratories around the world.

The combination of microwave background and galaxy data has recently produced another, perhaps even more perplexing result: our universe must contain not only dark matter but also a new form of energy which, in the absence of a better name, is often called ``dark energy.’ This gives rise to a cosmic repulsive force which counteracts the effect of gravity. Dark energy has dominated the overall evolution of the universe for the past 8 billion years or so, causing it to expand at an ever increasing rate. The origin of the dark energy is a profound mystery.

The Royal Society Discussion meeting brought together foremost world experts in cosmology and particle physics. They discussed the evidence for dark matter and dark energy, their effect on the expansion of the universe and on the properties of galaxies, speculate on the origin of the dark energy and describe experimental searches for the dark matter particles using ultra-high-technology devices. The meeting was pervaded by the certain knowledge that these are really exciting times in the quest for understanding the origin of our universe.

Rebecca Humphreys | Royal Society
Further information:
http://www.pubs.royalsoc.ac.uk
http://www.catchword.com/rsl/1364503X/previews/contp1-1.htm
http://www.lbl.gov/Science-Articles/Archive/Phys-HST-supernovae.html

More articles from Physics and Astronomy:

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

nachricht New survey hints at exotic origin for the Cold Spot
26.04.2017 | Royal Astronomical Society

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

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...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

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...

Im Focus: Deep inside Galaxy M87

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...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

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...

Im Focus: Microprocessors based on a layer of just three atoms

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>