Entanglement has been utilised by physicists to "stretch" the uncertainty principle and enhance quantum observations

 January 17, 2023 12:16 AM GMT

                                       German scientist Werner Heisenberg realised over a century ago that the principles of quantum physics imposed certain basic restrictions on how precisely we could quantify specific qualities of tiny things.

Measurements can be made more precisely than they otherwise could according to the rules of quantum physics.

We recently presented a strategy for improving measurements of small objects using quantum computers, which was published in Nature Physics. This might be helpful in a wide variety of emerging technologies, such as quantum communications, laser ranging, and biological sensing.

In certain cases, we were able to go beyond Heisenberg's "uncertainty principle," indicating that various contexts may call for the use of other uncertainty principles.

Quantum Uncertainties

It's easy to evaluate the characteristics of a massive, commonplace object like an automobile.

A automobile, for instance, has a clearly defined position, colour, and speed. They may be measured simultaneously or one at a time without any problems. Your car's colour or speed won't change if you measure its location.

But if you want to analyse small quantum things like electrons or photons, it gets considerably difficult (which are tiny little particles of light).

Quantum objects have a number of interrelated features. One property's measurement might have an impact on another.

For instance, monitoring an electron's location will change its speed, and vice versa.

Conjugate characteristics are what they possess.

Heisenberg's uncertainty principle is well demonstrated by the connection between these features. The more you know about one, the less you know about the other, hence it is impossible to concurrently measure two conjugate qualities of a quantum item to whatever level of accuracy you desire.

While the uncertainty principle places a cap on some measures' accuracy, actually hitting that cap can be quite difficult. However, it is crucial to measure quantum things as precisely as possible in order to advance basic research and create new technologies.

Entangled objects

In our recent work, we developed a method for more precisely determining the conjugate characteristics of quantum objects. The measurement might then be performed by our partners in several laboratories all around the world.

The novel method is based on entanglement, a peculiar property of quantum systems. We can measure two items more precisely when they are entangled than when they are not.

We discovered that we could build two identical quantum objects and entangle them using quantum computers, which can accurately control the state of quantum objects. We could more precisely identify the attributes of the entangled items by measuring them collectively than by measuring them separately.

The noise in the measurement is reduced and the accuracy is improved by measuring the two identical quantum objects that are entangled.

A less noisy future

It is also theoretically feasible to entangle and measure three or more quantum systems in order to increase accuracy. However, we haven't yet been able to successfully test this in an experimental setting.

Three identical entangled objects were measured together, but the findings were quite noisy. But in the future, it could be feasible to faithfully measure three copies of a quantum system concurrently as quantum computers advance and become more precise.

This work's ability to still detect a quantum improvement in extremely noisy conditions is one of its main advantages. This is encouraging for practical applications that will unavoidably take place in noisy real-world settings, such biomedical measurements.

What about the uncertainty principle?

The uncertainty principle, which was previously discussed, is also affected by this research.

According to one interpretation of the uncertainty principle, measuring the conjugate characteristics of quantum objects with infinite precision is not conceivable. Another interpretation, however, is that measuring one conjugate property of a quantum entity must inevitably cause some minimal disruption of the second corresponding property.

Based on the second interpretation, we were able to break an uncertainty principle in this study. This implies that different uncertainty rules may be required for various scenarios depending on what physical context is taken into account.

A global collaboration 

On a total of 19 different quantum computers, we put our theory to the test. These machines employed superconductors, trapped ions, and photonics, three different quantum computing technologies. Researchers from all over the world may connect to these machines, which are dispersed throughout Europe and America and are accessible over the internet, to collaborate and conduct significant research.

We conducted the work in cooperation with scientists from the Institute of Materials Research and Engineering at A*STAR in Singapore, the Universities of Jena, Innsbruck, and Macquarie, as well as the ARC Centre of Excellence for Quantum Computation and Communication Technology (CQC2T).

Under the terms of a Creative Commons licence, this article has been taken from THE CONVERSATION. Go here to read the original article.