A Uncovering the Mysteries of Dark Matter's Energy Content

AI Thread Summary
Harvard scientist Lisa Randall's statement that dark matter carries five times the energy of ordinary matter refers to its significant mass-energy contribution in the universe. Dark matter constitutes about five times more mass than normal matter, but it is essential to consider the role of dark energy as well. The discussion clarifies that E=mc² applies to dark matter, affirming its energy equivalence. Some participants suggest that Randall could have framed her statement to include dark matter's proportion of the total mass-energy content of the universe. Overall, the conversation emphasizes the complexity of dark matter's relationship with energy and mass in cosmology.
DLSieving
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What is meant by the statement by Harvard scientist Lisa Randall that dark matter carries five times the energy of ordinary matter? Does E=mc2 not apply to dark matter? Does the statement refer to ordinary energy or to dark energy?
 
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DLSieving said:
What is meant by the statement by Harvard scientist Lisa Randall that dark matter carries five times the energy of ordinary matter? Does E=mc2 not apply to dark matter? Does the statement refer to ordinary energy or to dark energy?
There's about five times as much mass in our universe in dark matter as there is in normal matter.
 
Ok thanks. She should have said something more like "Dark matter accounts for five sixths of the total massenergy content of the universe."
 
DLSieving said:
Ok thanks. She should have said something more like "Dark matter accounts for five sixths of the total massenergy content of the universe."
No, that's not an accurate statement, as there's also dark energy. Her statement was accurate as-is.
 
I thank you for your original answer, which makes perfect sense.
 

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