A description of gravity compatible with the principles of quantum mechanics has long been a widely pursued goal in physics. Existing theories of this 'quantum gravity' often involve mathematical corrections to Heisenberg's Uncertainty Principle (HUP), which quantifies the inherent limits in the accuracy of any quantum measurement.

These corrections arise when gravitational interactions are considered, leading to a 'Generalized Uncertainty Principle' (GUP). Two specific GUP models are often used: the first modifies the HUP with a linear correction, while the second introduces a quadratic one.

Through new research published in EPJ C, Serena Giardino and Vincenzo Salzano at the University of Szczecin in Poland have used well-established cosmological observations to place tighter constraints on the quadratic model, while discrediting the linear model.

The GUP can influence the black hole evaporation process first described by Stephen Hawking, and may also lead to better understanding of the relationship between thermodynamics and gravity.

Intriguingly, the GUP also places a lower limit on length scales that are possible to probe - below the so-called 'Planck length,' any concentration of energy would collapse under gravity to form a black hole. Previously, both the linear and quadratic GUP models were rigorously tested by comparing their predictions with data gathered in quantum experiments, placing stringent limits on their parameters.

In their study, Giardino and Salzano instead compared the predictions of GUP-influenced models of the universe with observations of cosmological phenomena, including supernovae and cosmic microwave background radiation. These comparisons were not widely made in the past, since the constraints they imposed on the GUP parameters were believed to be far weaker than those possible in quantum experiments.

However, the researchers' analysis revealed that stricter bounds could be imposed on the quadratic model, comparable to those placed by some quantum experiments. In addition, they showed that the linear correction to the HUP generally could not account for the observed data. Ultimately, these results highlight the promising role of cosmological observations in constraining the phenomenology of quantum gravity.

Research Report: "Cosmological constraints on GUP from modified Friedmann equations"

Related Links
Springer
The Physics of Time and Space

Tweet

Thanks for being here; We need your help. The Space Media Network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceMediaNetwork Contributor $5 Billed Once credit card or paypal		SpaceMediaNetwork Monthly Supporter $5 Billed Monthly paypal only

NANOGrav finds possible 'first hints' of low-frequency gravitational wave background
Morgantown WV (SPX) Feb 05, 2021
In data gathered and analyzed over 13 years, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) Physics Frontiers Center (PFC) has found an intriguing low-frequency signal that may be attributable to gravitational waves. NANOGrav researchers - including a number from West Virginia University's (WVU's) Department of Physics and Astronomy and the Center for Gravitational Waves and Cosmology - measure the times of arrival of radio pulses from exotic stars called pulsars with ... read more