Supermassive black holes are increasing the overall amount of entropy in the universe - and lessening the amount of time the universe has left.

Credit: Wikimedia

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SYDNEY: The amount of entropy, or disorder, in the observable universe is 30 times higher than previous estimates, report Australian astronomers, suggesting the universe may not have as much time left as previously thought.

Supermassive black holes, dark matter and stars are some of the contributors to the overall entropy of the universe, which is a measure of the irreversible processes occurring throughout.

Previous estimations of the total entropy of the universe were limited by insufficient measurements of supermassive black holes, as well as uncertainty about the entropy of dark matter, according to a study to be published in the Astrophysical Journal.

New advances on an old problem

The concept of entropy, which has existed in physics for almost 200 years, is central to the second law of thermodynamics and relates to the tendency of order in the universe to progressively turn to disorder.

Entropy is an important contributor to our understanding of both cosmology and biology. Life, along with every other chemical or physical process, cannot occur without producing entropy.

Everything from gravitational clustering, to supernovae, to the biological processes in our own bodies are contributors to the entropy budget of the universe; a budget which has been found to be 30 times larger than previously suspected, according to research by astrophysicists Chas Egan and Charles Lineweaver, from the Australian National University in Canberra.

“The work of Egan and Lineweaver is a significant advance in tallying the known sources of entropy in the universe,” says Adelaide based astrophysicist Roger Clay.

Gas tank of the universe running low

All particles in the universe emit energy as radiation, which results in entropy being produced. The amount of radiation emitted by a particle usually correlates to the temperature – high radiation produces high temperatures.

Entropy results from radiation as well as gravitation emissions, so calculating the amount of entropy in the entire observable universe involves identifying the major radiation and gravitation producing objects and their approximate number and size. Once this is known, entropy can be estimated by converting the known temperature of particles into units of energy.

Lineweaver describes the universe as a giant engine; the more efficient the engine, the lower the total entropy produced. His findings show that engine of our universe has a lot less gas left in the tank than we thought.

“It’s like driving along, thinking you have half a tank of gas, but when you get out and check it with a dipstick, you find you only have about a third of a tank.”