The Dark Energy: What is it? The evidence from 15 million galaxies, quasars and the dark energy spectroscopic instrument
We will try to find out what this dark energy is by using those numbers. Is that a modification to gravity? Is this a new formula of energy in the universe?” he says.
The Dark Energy Spectroscopic instrument is being used by the scientists to look at the history of the universe in the past. They used a telescope, instruments and data to analyze 15 million galaxies and quasars.
Ishak says there is no evidence to show that the universe has stopped expanding. He says it won’t happen for at least another 20 billion years.
We don’t know what’s missing in the model of our universe and we aren’t sure what to do about it. We’re just measuring things, and it means we need to stop, sit down and rethink our model of the universe. “What it’s showing us is….it is actually a wild type of dark energy that we need to understand and we don’t understand it yet.”
Fresh data have bolstered the discovery that dark energy, the mysterious force that makes galaxies accelerate away from each other, has weakened over the past 4.5 billion years.
An international group of more than 900 researchers studying the expansion of the universe presented their findings at the American Physical Society’s Global Physics Summit in Anaheim, Calif.
A force called dark energy is believed to be behind the rapid expansion of the universe, which may lead to it collapsing on its own in billions of years.
The DESI telescope: mapping the expansion history of the Universe with redshifted light from quasars to Galaxies and galaxies
Catherine Heymans, astronomer at the University of Edinburgh, UK, and the Astronomer Royal for Scotland, says she is paying attention now.
The DESI telescope is located at Kitt Peak National Observatory near Tucson, Arizona. It uses 5,000 robotic arms to point optical fibres at selected points where galaxies or quasars are located within its field of view. The fibres then deliver light to sensitive spectrographs that measure how much each object is redshifted — meaning the degree to which its light waves were stretched by the expansion of space on their way to Earth. Researchers can estimate an object’s distance using its redshift, to produce a 3D map of the Universe’s expansion history.
By tracking the evolving size of BAOs, researchers can reconstruct how the Universe’s rate of expansion has changed over the eons. Around 5 billion years ago, the expansion switched from decelerating to accelerating under the push of dark energy. Until last year, cosmology data were all consistent with dark energy being a cosmological constant — which meant that the Universe should continue to expand at an increasingly fast rate.