Some researchers have explored the latent connection between general relativity and quantum mechanics. This discovery may force physicists to rethink the nature of space and time.
The Nature of Space and Time
In 1915, Albert Einstein published the theory of general relativity, which describes gravity as a fundamental property of spacetime. He presented a set of equations that describe the warping of spacetime related to energy and momentum.
According to Einstein, gravity is not just an ordinary force, as it was discovered by physicist Isaac Newton. Gravity can be viewed as a curvature of spacetime caused by the mass of objects.
Einstein’s theory also explains the nature of cosmic black holes, where the gravitational force is so strong that light cannot escape. Furthermore, according to the theory of relativity, gravity also distorts time, with stronger gravitational forces causing time to pass more slowly.
In the 1970s, physicists Stephen Hawking and Jacob Bekenstein noted the connection between the surface area of black holes and their quantum structures. This marked the initial insights into the linkage between Einstein’s general relativity and quantum mechanics.
Less than three decades later, theoretical physicist Juan Maldacena observed another connection between gravity and the quantum world. This connection led to the creation of a model based on the idea that spacetime can be created or destroyed by altering the entanglement between different surface regions of an object. In other words, this implies that spacetime is a product of entanglement between objects.
There is a connection between general relativity and quantum mechanics. (Image: Internet).
To explore further, researchers ChunJun Cao and Sean Carroll from the California Institute of Technology conducted several experiments. They aimed to determine whether they could derive the characteristics of gravity (as understood in general relativity) using a framework where spacetime arises outside of quantum entanglement. Their research was recently published on arXiv.
Using an abstract mathematical concept known as Hilbert space, Cao and Carroll found similarities between the equations governing quantum entanglement and Einstein’s equations of general relativity. This supports the idea that spacetime and gravity emerge from entanglement.
Carroll stated that the next step in their research is to ascertain the accuracy of the assumptions they made. He noted: “One of the most obvious things is to check whether the symmetry of relativity appears in this framework – particularly the idea that physical laws do not depend on our speed through space.”
The Theory of Everything
Today, most of what we know about the physical aspects of the universe can be explained by general relativity or quantum mechanics. General relativity has perfectly demonstrated its role in explaining the behavior of objects on a very large scale, such as planets or galaxies. Meanwhile, quantum mechanics helps us understand the very small, such as atoms and atomic molecules.
However, the two theories seem incompatible with each other. This has led physicists to strive for a “theory of everything” – a unified framework that can explain all, including the nature of space and time.
Scientists rethink the nature of time and space. (Image: Internet).
Since gravity and spacetime are essential parts of “everything”, Carroll believes that the research he and Cao conducted could advance the pursuit of a unified theory between general relativity and quantum mechanics. However, he notes that this is a challenging endeavor.
“Our research does not yet say much about other natural forces, so we are still far from a final result,” Carroll stated. However, if we can discover such a theory, we could answer some of the biggest questions scientists face. We might understand the true nature of dark matter, dark energy, black holes, and other mysterious objects in the universe.
Currently, researchers are tapping into the potential of the quantum world to improve computing systems, and a theory of everything could expedite progress by revealing new insights in a still opaque field.
According to researcher Carroll, as theoretical physicists pursue a theory of everything, each new study – whether effective or not – still helps us get closer to the mysteries of the universe.
