Ancient Neutrinos Could Put String Theory and Quantum Loop Gravity to the Test

Sep 14, 2005

The distribution of ancient neutrinos may eliminate some of the most promising theories linking gravity and quantum mechanics, according to a theoretical analysis put forth at the Perimeter Institute in Canada. Many physicists believe that combining gravity and quantum mechanics into a single theory is one of the most important problems in science today.

Leading attempts to create a unified theory of gravity and quantum mechanics, such as string theory and loop quantum gravity, make sense in a universe in which gravity is subordinate to the laws of quantum mechanics. However, problems with these sorts of theories have led some to propose that gravity and quantum mechanics are equal contributors to the final unified theory.

According to this hypothesis, gravity breaks down the quantum nature of objects. The heavier the object, the quicker gravity leads to the breakdown â€" that is one reason that large objects, such as baseballs, obey the classical physics of Newton, while light objects such as electrons and other particles obey the counterintuitive laws of quantum mechanics. The new research suggests that this idea can be tested using neutrinos created in the early universe.

If gravity breaks down the quantum nature of neutrinos, this should be evident in ratios of the types of neutrinos detected at next generation neutrino experiments such as IceCube, a one cubic kilometer neutrino detector currently being built beneath the ice of Antarctica. Such a result would require physicists to rethink popular theories including string theory and quantum loop gravity. It would also mean that the physics of the early universe was fundamentally different than it is today.

J. Christian
Physical Review Letters (upcoming article)

Source: American Physical Society

Explore further: Why seashells' mineral forms differently in seawater

add to favorites email to friend print save as pdf

Related Stories

Space-time theory may reconcile black hole conundrum

Feb 09, 2015

We've come a long way in 13.8 billion years; but despite our impressively extensive understanding of the Universe, there are still a few strings left untied. For one, there is the oft-cited disconnect between ...

The Wild West of physics

Jan 22, 2015

Call it macro-micro physics: the study of the huge paired with the study of the very, very small.

Mathematicians prove the Umbral Moonshine Conjecture

Dec 15, 2014

Monstrous moonshine, a quirky pattern of the monster group in theoretical math, has a shadow - umbral moonshine. Mathematicians have now proved this insight, known as the Umbral Moonshine Conjecture, offering ...

Recommended for you

Unified theory for skyrmion-materials

3 hours ago

Magnetic vortex structures, so-called skyrmions, could in future store and process information very efficiently. They could also be the basis for high-frequency components. For the first time, a team of physicists ...

Scientists provide new data on the nature of dark matter

4 hours ago

Recent research conducted by scientists from the University of Granada sheds light on the nature of dark matter, one of the most important mysteries in physics. As indirect evidence provided by its gravitational ...

Why seashells' mineral forms differently in seawater

7 hours ago

For almost a century, scientists have been puzzled by a process that is crucial to much of the life in Earth's oceans: Why does calcium carbonate, the tough material of seashells and corals, sometimes take ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.