In a groundbreaking development that challenges long-held perceptions of the cosmos, a team of researchers from Radboud University Nijmegen in the Netherlands have unveiled compelling evidence suggesting that celestial bodies beyond black holes, including neutron stars and white dwarfs, undergo a slow but inevitable evaporation process akin to Hawking radiation. This revelation not only extends the boundaries of astrophysical theory but also dramatically revises estimates regarding the ultimate fate of the universe, condensing astronomical timescales from unfathomable eons to durations that, while still staggeringly long, are infinitely more finite than previously imagined.
The pioneering investigation, conducted by black hole expert Heino Falcke, quantum physicist Michael Wondrak, and mathematician Walter van Suijlekom, builds upon their 2023 work wherein they initially proposed that Hawking-like radiation is not an exclusive phenomenon of black holes but applies more broadly to other massive gravitational entities. Their latest publication rigorously tackles the question that intrigued their global audience post their initial findings: how long does this evaporation process actually take for different cosmic objects?
At the heart of their inquiry lies the reimagining of Hawking radiation—a theoretical process first articulated by Stephen Hawking in 1975, which profoundly altered our understanding of black holes by suggesting they must lose mass over time through quantum effects at their event horizons. The classic view held that this radiation causes black holes to dissipate incredibly slowly, ultimately vanishing over fantastically long timescales. However, this new study extends the radiation’s influence to neutron stars, white dwarfs, and even inorganic and organic matter such as moons and humans, positing that these objects emit Hawking-like radiation based principally on their density.
Their calculations reveal a startling reassessment of the endgame for the universe. Previously, it was believed that white dwarfs—the remnants of stars with relatively low mass—would persist for about 10^1100 years before decaying, a figure so colossal as to dwarf the current age of the universe by an unimaginable margin. Contrary to this, the Radboud team’s model predicts the universe’s tangible demise within approximately 10^78 years, dictated by the slow evaporation of white dwarfs through this hitherto underestimated mechanism. This adjustment suggests a cosmological timeline that is profoundly shorter yet still spans periods that transcend any human conception of time.
One particularly striking contribution is the insight regarding neutron stars and stellar black holes. Neutron stars—extremely dense stellar remnants composed predominantly of neutrons—were shown to share a nearly identical evaporation timeline with stellar black holes, roughly 10^67 years. This equivalence defied initial expectations, primarily because black holes’ immense gravitational fields and their surrounding event horizons might be assumed to accelerate evaporation through intense quantum effects. However, the absence of a physical surface in black holes introduces a unique self-absorption phenomenon whereby some radiation is reabsorbed rather than emitted, effectively throttling the decay process. Neutron stars, possessing a tangible surface, lack this inhibitory mechanism, leading to comparable evaporation times despite differing gravitational intensities.
Extending their quantum gravitational framework even further, the researchers quantified the evaporation durations for objects far closer to home: the Moon and humans. The extrapolated timeline of approximately 10^90 years for these bodies, dictated by Hawking-like radiation, vastly exceeds any realistic biological or planetary horizon, highlighting the purely theoretical nature of the mechanism at such scales. While practical extinction of organic life or the physical dissolution of terrestrial bodies will occur due to many far more immediate processes, these calculations beautifully illustrate the universality and predictive power of quantum field theories applied within gravitational contexts.
The intricate dance of astrophysics, quantum mechanics, and abstract mathematics exhibited in this research showcases the interdisciplinary nature of addressing some of the most profound questions about the universe. Walter van Suijlekom emphasizes that probing extremes—such as the incredibly slow evaporation of dense stellar remnants—provides fertile ground for refining theoretical frameworks and may eventually lead to unveiling deeper aspects of quantum gravity, a realm where general relativity and quantum mechanics intersect but remain fundamentally at odds.
The scientific community stands to benefit not only from these novel calculations but also from the recalibrated expectations about cosmic longevity and the lifecycle of matter in the far future. These findings necessitate a nuanced appreciation of how objects with differing densities radiate energy and mass across cosmological timescales and suggest that the universe’s decay follows a predictable pattern grounded in fundamental physical principles rather than solely speculative extrapolations.
Moreover, this investigation reflects a remarkable methodological synergy: astrophysical phenomena traditionally considered in cosmic contexts are now being examined with a rigorous quantum lens to derive tangible, albeit extremely long-term, physical consequences. The evidence supporting the universality of Hawking-like radiation invites renewed scrutiny into other astrophysical phenomena and stochastic processes that might influence the gradual fate of matter and energy distribution in the cosmos.
Heino Falcke, speaking as the lead author, underscores the scientific excitement surrounding the recalculated timelines: “While this places the ultimate demise of our universe substantially sooner than previously thought, it reassures us that such an event lies so vastly in the future that it poses no immediate concern.” His balanced perspective melds rigor with a modicum of humor, acknowledging the awe-inspiring scales of cosmic erosion while inviting a fresh narrative built on quantitative foundations.
Intriguingly, the self-absorption properties of black holes open new avenues for investigating event horizon physics and quantum field effects in extreme gravity environments. Understanding how black holes’ radiation is partially reabsorbed enhances models of black hole thermodynamics and entropy, areas deeply linked to unresolved puzzles in theoretical physics, including the infamous information paradox.
This work, published in the Journal of Cosmology and Astroparticle Physics, adds vital empirical vigor to abstract theoretical models, promising a richer comprehension of the deep time evolution of the universe and the entities it contains. By addressing direct questions raised by the scientific and lay communities, the researchers showcase an impressive commitment to both foundational theory and public scientific discourse.
Ultimately, these findings invite us to reconsider the universe not as an eternal and intractable expanse but as an evolving system subject to subtle quantum processes that, over extraordinarily protracted durations, inexorably dismantle even the densest of stars. Such perspectives deepen humanity’s connection to the cosmos and enrich the tapestry of cosmic evolution narratives, merging the macroscopic dance of galaxies with microscopic quantum fluctuations into a coherent, fascinating story.
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Subject of Research: Hawking-like radiation causing the evaporation of neutron stars, white dwarfs, black holes, and other matter; implications for the lifetime of the universe.
Article Title: Universe decays faster than thought, but still takes a long time
News Publication Date: 12-May-2025
Web References:
– https://doi.org/10.48550/arXiv.2410.14734
– https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.130.221502
– https://en.wikipedia.org/wiki/Hawking_radiation
Image Credits: Credit: (c) Daniëlle Futselaar/artsource.nl
Keywords
Universe, Cosmology, Astronomy, Radiation, Black holes, Stars
