However, the fundamental laws of quantum physics always involve a certain degree of uncertainty.
Now a team of researchers from TU Wien, Chalmers University of Technology, Sweden, and the University of Malta has demonstrated that special tricks can be used to increase accuracy exponentially.
“Every clock needs two components: first, a time base generator, such as a pendulum in a pendulum clock, or even a quantum oscillation.
After one complete oscillation, the pendulum of a pendulum clock is exactly where it was before.
You can connect a whole series of such time-measuring devices in series and count how many of them have already passed through—similar to how one clock hand counts how many laps the other clock hand has already completed.
Quantum metrology is a field of study that focuses on how to use the peculiar characteristics of quantum particles to make incredibly precise measurements. A prime example is the atomic clock, which measures time far more precisely than traditional clocks by utilizing the quantum characteristics of atoms.
Nonetheless, a certain amount of uncertainty is always present in the fundamental laws of quantum physics. It is necessary to accept a certain amount of statistical noise or randomness. As a result, the accuracy that can be attained has fundamental limitations. The idea that a clock that is twice as accurate needs at least twice as much energy was thought to be an unchangeable law until recently.
Researchers from the University of Malta, Chalmers University of Technology in Sweden, and TU Wien have now shown that using certain techniques can greatly improve accuracy. Using two distinct time scales—much like a clock has a second and a minute hand—is essential.
The journal Nature Physics publishes the paper.
What is a clock exactly?
“In principle, we have examined which clocks might be feasible,” says Prof. TU Wien’s Atomic Institute’s Marcus Huber. A time base generator, like a pendulum in a pendulum clock or even a quantum oscillation, is the first of two essential parts of any clock. The second component is a counter, which is any element that keeps track of how many time units that the time base generator has already passed. “,”.
There is always a chance that the time base generator will return to its initial state. In a pendulum clock, the pendulum returns to its initial position after a single full oscillation. In an atomic clock, the cesium atom returns to its initial state after a predetermined number of oscillations. However, if the counter doesn’t change, the clock won’t work.
According to TU Wien’s Florian Meier, “this means that every clock must be connected to an irreversible process.”. This indicates that every clock raises the entropy in the universe; otherwise, it is not a clock, according to thermodynamics. The air molecules surrounding a pendulum clock produce some heat and disorder, and each laser beam that reads the state of an atomic clock produces heat, radiation, and entropy.
“A hypothetical clock with very high precision would have to generate a certain amount of entropy, and, consequently, that clock would require a certain amount of energy,” says Prof. Huber. Up until now, it appeared that the relationship was linear: at least a thousand times as much entropy and a thousand times as much energy were required to achieve a thousand times the precision. “.
classical time and quantum time.
But now, the TU Wien research team, the Austrian Academy of Sciences (ÖAW) in Vienna, and teams from Chalmers University of Technology in Sweden and the University of Malta have demonstrated that this seemingly inflexible rule can be broken by employing two distinct time scales.
“To measure time, for instance, you can use particles that move from one area to another, much like how sand grains show the time by falling from the top of the glass to the bottom,” Meier explains. Similar to how one clock hand counts the number of laps the other clock hand has completed, you can connect an entire array of these time-measuring devices in series and determine how many of them have already passed through.
According to Prof., “this way, you can increase accuracy, but not without investing more energy,”. Hauer. The reason for this is that entropy rises each time one clock hand completes a full rotation and the other clock hand is measured at a new location—or, perhaps more accurately, each time the surrounding environment detects that this hand has moved. The process of counting cannot be reversed. “..”.
The particles can, however, also move through the entire structure, which is another type of particle transport made possible by quantum physics. E. everywhere on the clock dial, without any measurement. During this process, the particle is essentially everywhere at once; it doesn’t have a distinct location until it gets there, and only then is it measured, increasing entropy in an irreversible process.
similar to the hands of a second and minute clock.
“So we have a slow one, namely the arrival of the particle at the very end,” says Yuri Minoguchi of TU Wien. “We also have a fast process that does not cause entropy—quantum transport.”. The key feature of our approach is that only the slower hand actually produces entropy; the other hand acts solely in accordance with quantum physics. “.”.
It has now been demonstrated by the team that this approach allows accuracy to increase exponentially with entropy. This implies that a great deal more precision can be attained than would have been believed feasible based on earlier theories.
Superconducting circuits, one of the most cutting-edge quantum technologies now on the market, could be used to test the theory in the real world, according to Simone Gasparinetti, co-author of the study and head of the experimental team at Chalmers.
