Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Intense heat killed the Universe's would-be galaxies

02.07.2009
Our Milky Way galaxy only survived because it was already immersed in a large clump of dark matter which trapped gases inside it, scientists led by Durham University's Institute for Computational Cosmology (ICC) found.

The research, to be presented at an international conference today (Wednesday, July 1), also forms a core part of a new ICC movie charting the evolution of the Milky Way to be shown at the Royal Society.

The researchers said that the early Milky Way, which had begun forming stars, held on to the raw gaseous material from which further stars would be made. This material would otherwise have been evaporated by the high temperatures generated by the "ignition" of the Universe about half-a-billion years after the Big Bang.

Tiny galaxies, inside small clumps of dark matter, were blasted away by the heat which reached approximate temperatures of between 20,000 and 100,000 degrees centigrade, the scientists, including experts at Japan's University of Tsukuba, said.

Dark matter is thought to make up 85 per cent of the Universe's mass and is believed to be one of the building blocks of galaxy formation.

Using computer simulations carried out by the international Virgo Consortium (which is led by Durham) the scientists examined why galaxies like the Milky Way have so few companion galaxies or satellites.

Astronomers have found a few dozen small satellites around the Milky Way, but the simulations revealed that hundreds of thousands of small clumps of dark matter should be orbiting our galaxy.

The scientists said the heat from the early stars and black holes rendered this dark matter barren and unable to support the development of satellite star systems.

The findings will be presented to The Unity of the Universe conference to be held at the Institute of Cosmology and Gravitation, at the University of Portsmouth on Wednesday, July 1. The work has been funded by the Science and Technology Facilities Council (STFC) and the Japanese Society for the Promotion of Science.

The simulations also form part of a new ICC movie – called Our Cosmic Origins – which combines ground-breaking simulations with observations of galaxies to track the evolution of the Milky Way over the 13-billion-year history of the Universe.

The movie is part of the ICC's exhibit at The Royal Society's annual Summer Science Exhibition which runs until this Saturday (July 4).

Joint lead investigator Professor Carlos Frenk, Director of the Institute for Computational Cosmology, at Durham University, said: "The validity of the standard model of our Universe hinges on finding a satisfactory explanation for why galaxies like the Milky Way have so few companions.

"The simulations show that hundreds of thousands of small dark matter clumps should be orbiting the Milky Way, but they didn't form galaxies.

"We can demonstrate that it was almost impossible for these potential galaxies to survive the extreme heat generated by the first stars and black holes.

"The heat evaporated gas from the small dark matter clumps, rendering them barren. Only a few dozen front-runners which had a head start on making stars before the Universe ignited managed to survive."

By providing a natural explanation for the origin of galaxies, the simulations support the view that cold dark matter is the best candidate for the mysterious material believed to make up the majority of our Universe, the scientists added.

It is now up to experimental physicists to either find this dark matter directly or to make it in a particle accelerator such as the Large Hadron Collider at CERN.

Professor Frenk, added: "Identifying the dark matter is not only one of the most pressing problems in science today, but also the key to understanding the formation of galaxies."

Joint lead investigator Dr Takashi Okamoto from the University of Tsukuba said: "These are still early days in trying to make realistic galaxies in a computer, but our results are very encouraging."

Leighton Kitson | EurekAlert!
Further information:
http://www.durham.ac.uk

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

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

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

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | 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

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>