By Nikola Undoubtedly, Albert Einstein was a very intelligent man. Though Einstein acknowledged its shortcomings, his general theory of relativity represented the 21st century’s response to Newton’s universal theory of gravity.
It works well for running daily errands, just like the used car you purchased with your first salary. Push it too hard up a steep slope or park it near a quantum strip mall, and that engine shudders to a stop.
Hamidreza Fazlollahi, a graduate student studying astrophysics at the Peoples’ Friendship University of Russia, suggests taking a closer look at the parts to determine which aren’t as important as they first appear.
He thinks general relativity might survive a few more hiccups in the road by figuring out a law conserving a mathematical characteristic involving energy and momentum.
The tendency of objects with mass to gravitate toward one other is called gravity. Gravity models must explain why masses attract, whether in the case of colliding galaxies, a moon defying inertia in its pull towards a planet, or an apple falling to Earth from a tree’s upper branches.
However, a theory of this kind must also function in a universe where particles with the same charge repel one another, explain how atomic nuclei cling to one another with extraordinary power, or explain how neutrons spontaneously decay into protons. Additionally, it must remain motionless until space-time becomes so condensed or masses are so dense that light is no longer able to escape.
And really, as good as it is, general relativity just isn’t up to the task.
It is common knowledge that Einstein’s theory of gravity has a non-renormalizability issue. Numerous attempts to approach it as a low-energy theory have resulted from it, according to Fazlollahi.
Theoretical physicists use renormalization as a magical trick to make frustrating infinities in quantum fields vanish. Use a few of these tricks to get your model back on firm ground when loops of reality appear to fade endlessly into the distance in a perplexing fractal.
The theory of general relativity complicates this. Because of this, the sandy beaches of quantum mechanics and the rolling fields of space-time it represents are unable to mesh, creating an incompatible system of physics that requires two theories of nature when just one would make far more sense.
Luckily, a lot of presumptions also went into Einstein’s formulation of general relativity. Even though he included them for good reasons, the universe may ultimately disagree with his assessment of their necessity.
The idea that energy and momentum conservation are consistent with space and time curvature is one of the more basic tenets of general relativity. To put it another way, unless there is a change in forces, traveling from point A to point B across an ocean of space-time should not impact your energy or velocity.
In a universe that is flat and empty, this assumption makes perfect sense. However, the universe is curved and pitted, rich with galaxies, electrons, and virtual particles that appear and disappear.
English physicist Peter Rastall developed a subtle variation on the classic model of energy-momentum conservation law in 1976. It proposed a nontrivial relationship between matter and the curvature of space and time.
Fazlollahi took a different route but followed a similar line of reasoning when he looked at relativistic thermodynamics, the study of energy exchange under very harsh circumstances, and discovered transformations of momentum and energy that are comparable to general relativity equations.
The end result is a novel theory that sheds light on certain basic assumptions while still helping explain phenomena like the expansion of the universe and the development of gravity from curved space-time.
Even with its many advantages, Einstein’s ingenious theory is obviously flawed in some way. Being unduly cautious when everything’s fate is at stake is pointless.
The European Physical Journal C published the results of this study.
Nikola