Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Penn astrophysicist outlines a multi-pronged approach in the hunt for dark energy

21.02.2005


For the last few years evidence that we are living on a very "weird" universe has been growing: the expansion of the universe is accelerating, and one theory proposed to account for this acceleration is what has been termed "dark energy."

In order to find out what this mysterious energy really is, astronomers need to compare astrophysical observations that are at first sight completely unrelated. At a session on dark energy at the Annual Meeting of the American Association for the Advancement of Science today, University of Pennsylvania astrophysicist Licia Verde outlines how the hunt for dark energy will draw on the avalanche of recent and forthcoming data on surveys of objects throughout the universe.

"We were just coming to grips with ’dark matter’ when, out of the blue, observations tells us that something is propelling the universe apart and that this something comprises about 73 percent of existence," said Verde, an assistant professor in Penn’s Department of Physics and Astronomy. "Unlike dark matter, which, as mysterious as it may be, is still matter, dark energy is ’dark’ only because astronomers simply do not know what it is. At the heart of the dilemma, however, hides the answer to just what all this universe stuff is made from anyway."



For example, some clues to the nature of dark energy have been obtained by comparing the state of the universe at its birth – as depicted in the Cosmic Microwave Background experiments – with how it exists today, using data taken from galaxy surveys. One of the first sources of data will come from the ongoing series of surveys that look at the state of galaxies today and other celestial objects which we see as they were few billion years ago.

These observations become even more powerful in combination with observations of the Cosmic Microwave Background, which provide a look at the young universe by measuring the residue of the Big Bang itself. If dark energy changes the way the universe expands, the distance between galaxies and the CMB and the time elapsed between the CMB and the era of galaxies must carry some clues about dark energy, left behind like fingerprints on space-time.

"If you think of the universe as a great sea, where space is water, over time gravity, like the wind, made ripples in that water that turned into waves. That’s the universe today, a surfer’s paradise," Verde said. "Of course, a surfer would end up in a different place if you changed the composition of water or if you let the wind blow longer. Likewise, the position and the properties of the galaxies today tell us something about how they surfed there and the composition of the universe that took them there.

"We’re drawing on data compiled from astronomers across the globe in surveys of galaxies, supernovae, clusters of galaxies and other objects in space from as many different viewpoints as possible," Verde said. "Part of the difficulty studying dark energy is that we are still not sure what we are looking for, so we are looking to seemingly unrelated sources that might tell us something about the properties of dark energy.

According to Verde, if these approaches fail, it could mean that the current mode of thinking about the universe is wrong. If it turns out that dark energy does not exist after all, it would be the cause of a basic re-thinking of our understanding of astrophysics. "Finding out about the nature of dark energy will have consequences for both astronomy and fundamental physics," Verde said. "In other words, the question of dark energy cannot be answered without connecting the cosmological properties of the universe to the fundamental properties of matter on the subatomic level – from the infinitely small to the infinitely big."

Greg Lester | EurekAlert!
Further information:
http://www.upenn.edu

More articles from Physics and Astronomy:

nachricht First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science

nachricht Nuclear physicists leap into quantum computing with first simulations of atomic nucleus
24.05.2018 | DOE/Oak Ridge National Laboratory

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: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

Surgery involving ultrasound energy found to treat high blood pressure

24.05.2018 | Medical Engineering

First chip-scale broadband optical system that can sense molecules in the mid-IR

24.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>