Universe Expected to Decay in 10⁷⁸ Years, Much Sooner Than Previously Thought

Dutch researchers have revised the timeline for the universe’s ultimate decay—driven by Hawking-like radiation—from an almost inconceivable 10¹¹⁰⁰ years down to about 10⁷⁸ years, implying even the galaxy’s most durable white dwarfs will vanish far sooner than once believed.

1. What Is Cosmic “Decay”?

In cosmology, the term “decay” refers to the gradual erosion of all matter through processes like Hawking radiation. Eventually, even the most stable cosmic structures lose energy until nothing remains but cold, dark radiation—what scientists call "heat death."

2. The New Calculation

A team at Radboud University in the Netherlands applied Hawking-like emissions not just to black holes but to all forms of residual cosmic matter. Their quantum field calculations in curved spacetime suggest that universal decay will happen in about 10⁷⁸ years—22 orders of magnitude earlier than past estimates.

3. How Does This Compare to Earlier Estimates?

• Previous models suggested proton decay would take around 10¹¹⁰⁰ years to eliminate white dwarfs.
• Black hole evaporation was already expected to take up to 10¹⁰⁰ years for supermassive black holes.
• This study dramatically shortens the universal lifespan based on quantum effects acting on all matter.

4. Broader Implications

• Degenerate Era shortened: Stellar remnants will decay much sooner than thought.
• Heat death arrives earlier: The universe's end state is now closer in cosmic terms.
• New theoretical questions: Applying Hawking radiation universally challenges current quantum gravity models.

5. Looking Ahead

This recalibration reminds us how speculative our cosmic timeline still is. New discoveries and quantum theories may continue to reshape our understanding of the universe’s fate.

Source: Phys.org