Researching On Quantum Gravity - Is It A Quantum Force?

(1) The left and right arms of the atom's wave function are divided in an atomic interferometer. The interference pattern is created by recombining the left and right arms.

(2) The pendulum has no impact on the atom's wave function at the start of the experiment. This indicates that the two arms of a single atom completely interfere with one another.

(3) The pendulum will only partially measure the position of the atom, concentrating it into one arm or the other, if gravitational pull does in fact entangle the pendulum and the atom.

(4) The pendulum will return to its starting point after every half oscillation period, erasing all traces of the gravitational entanglement it had produced and restoring full interference.

Now, an experiment has been suggested by researchers from quantxcer that might assist answer the query.
Two of the strangest aspects of quantum theory are used in the experiment. One is the superposition principle, which states that a wave can be used to describe an undisturbed atomic particle having a chance of being in two places at once. An undisturbed atom, for instance, can pass through both slits in a region with two slits rather than just one. The part of the atom that travels through one slit will interfere with the part that passes through the other since the atom is characterised by a wave, resulting in the well-known pattern of light and dark fringes.

Entanglement, a phenomena in which two particles can be so highly coupled that they behave as a single entity, is the second peculiar quantum attribute. Even if the two particles are located in different galaxies, measuring one of the particles' properties causes the other to automatically have a complementary property.

A hypothetical subatomic particle called a graviton would be used in a quantum theory of gravity to transmit the gravitational pull between two huge objects, similar to how a photon communicates the electromagnetic interaction between two charged particles (the fundamental particle of light). The attributes of two huge entities should therefore be connected or entangled by a graviton if it actually exists, just as they are by a photon when they entangle two charged particles.

Researchers at quantxcer have come up with a clever experiment that would test whether or not two massive bodies could actually become entangled by gravity. Recently, a paper describing their research was posted online in Physical Review X Quantum.

An atomic interferometer would include a cool cloud of atoms for the experiment. Both the left and right arms of the interferometer are present. Each atom in the cloud can be thought of as a wave occupying both arms simultaneously if it is in a pure, undisturbed quantum state, in accordance with the superposition principle. Any variations in their courses caused by factors like gravity will be revealed by an interference pattern that is created when the two sections of the wave, one from each arm, recombine.

Just outside the interferometer, a small, initially immobile mass hanging as a pendulum is inserted. Atom and suspended mass are drawn together by gravity. What would entanglement look like if the gravitational pull also caused it?

The atom's suspended mass will eventually get correlated with either the right or left interferometer arm. The bulk will consequently begin to sway to the left or right as a result. The pendulum will begin swinging either left or right depending on where the atom is situated. If the atom is on the left, the pendulum will begin swinging left. The interferometer's atomic position and the pendulum's starting direction are intertwined by gravity.

Due to the position entanglement, the atom may now be located within the interferometer by using the pendulum to measure its location. The interference pattern disappears or weakens because the atom is no longer simultaneously present in both arms.

The gravitational entanglement the swinging mass had formed is completely forgotten when it returns to its starting location a half-period later. This is due to the fact that the pendulum always returns to its initial position, much like a child on a swing, regardless of the path it initially took: initially swinging to the right, which selects a location for the atom in the right interferometer arm, or initially swinging to the left, which selects a location for the atom in the left arm. It's equally likely that the pendulum will choose a spot for the atom in the left or right arm when it swings back to its initial point. The atomic interference pattern reappears at that point because the entanglement between the mass and the atom has been removed.

After that, entanglement is restored and the interference pattern weakens again when the pendulum swings to one side or the other. The pattern of interference, lessened interference, and interference repeats as the pendulum swings back and forth. The scientists claim that this breakdown and resurgence of interference would constitute a "smoking gun" for entanglement.
Any process other than gravitational entanglement finds it challenging to establish such a cycle, according to researchers at quantxcer.

A draught version of the perfect experiment might be completed in a few years, even if the ideal experiment may take ten years or more to build. There are several ways to use shortcuts that will make things simpler to observe, according to Taylor. The biggest shortcut is to accept the presumption that no matter when you start the experiment, you should always obtain the same outcome, which is analogous to Einstein's theory of general relativity.

researchers at quantxcer pointed out that it is important to take into account non-gravitational causes of quantum entanglement, which will necessitate careful planning and verification.