Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Astronomers Gravitate Toward Einstein’s Telescope

24.02.2009
Scientists are harnessing the cosmos as a scientific “instrument” in their quest to determine the makeup of the universe.

The University of Chicago’s Evalyn Gates calls the instrument “Einstein’s telescope.” The instrument is actually the phenomenon of gravitational lensing, which acts as a sort of natural telescope. Gates’s new book, Einstein’s Telescope: The Hunt for Dark Matter and Dark Energy in the Universe, explains how it works.

Although based on Albert Einstein’s general theory of relativity, the effect is easily demonstrated. Look at a light through the bottom of a wine glass, Gates recommends, and see the resulting light distortion.

“Einstein’s telescope is using the universe itself as a lens through which we can seek out galaxies that would otherwise be too faint to be seen,” says Gates, Assistant Director of the University’s Kavli Institute for Cosmological Physics.

Einstein’s first inklings

Long ago Einstein recognized the potential existence of gravitational lensing, a consequence of his theory of general relativity. According to general relativity, celestial objects create dimples in space-time that bend the light traveling from behind.

Einstein realized that the gravitational influence of a foreground star could theoretically bend the light of another star sitting almost directly far beyond it, producing two images of the background star.

“Gravitational lensing magnifies things as well as making multiple images and distorting the shape of images, so you can actually use it as a magnifying glass,” Gates explains.

But, assuming that the effect would be too weak to detect, Einstein immediately dismissed its significance. “What he didn’t anticipate, among other things, were the incredible leaps forward in telescope technology,” Gates says.

Seeing the invisible

Astronomers now use gravitational lensing to look for dark matter and the imprint of dark energy, two of the greatest modern scientific mysteries.

Dark energy, which acts in opposition to gravity, is the dominant force in the universe.

“We can’t see dark energy directly by any means, but we’re looking for how it has sculpted the matter distribution of the universe over the past few billion years, since it’s been the dominant factor, and also how it has affected the rate at which the Universe is expanding” Gates says.

And gravitational lensing is essentially the only method astronomers have for tracing out the web of dark matter that pervades the Universe, and determining how dark energy has impacted the evolution of this web. “It’s really hot scientifically,” she says.

Like dark energy, dark matter is also invisible. It accounts for most of the matter in the universe, but exactly what it is remains unknown. Scientists only know that dark matter differs significantly from normal matter (which is essentially composed of protons and neutrons) that dominates everyday life.

“What we’re made of is just about five percent of everything that’s in the universe,” Gates says.

In 1990s scientists wondered if a significant quantity of dark matter in the halo consisted of MACHOs (Massive Astrophysical Compact Halo Objects) – faint objects such as dim stars, Jupiter-sized planets or stellar-mass black holes that are all composed of normal matter but hard to see.

Gates and her collaborators were among the researchers who used gravitational lensing to search for MACHOs within the halo of the Milky Way galaxy.

“We have seen MACHOs – but what we found is that they make up at most a small fraction of the galactic halo,” Gates said.

A look into galaxies past

Scientists also use galaxy clusters as gravitational lenses to probe 13 billion years back into the history of the universe. “They’re seeing some of the very first galaxies,” she says.

Gravitational lensing offers astrophysicists a tool comparable to magnetic resonance imaging and computing tomography, which have provided health professionals with unprecedented new views of the human body.

“Gravitational lensing is going to allow us to image the universe in ways that wouldn’t have been possible even 50 years ago,” she says.

During the 20th century, quantum mechanics and general relativity radically altered scientists’ view of the universe, Gates says. Investigations of dark matter and dark energy may do likewise.

“It may lead us to another revolution in our understanding of the most fundamental aspects of the universe, time, matter, and energy.”

Steve Koppes | Newswise Science News
Further information:
http://www.uchicago.edu
http://www.newswise.com/articles/view/549380/?sc=dwhr;xy=5048111

More articles from Physics and Astronomy:

nachricht When electric fields make spins swirl
15.11.2018 | Institute for Basic Science

nachricht Gravitational waves from a merged hyper-massive neutron star
15.11.2018 | 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: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>