Using a quantum computer to turn back time
The passage of time is a one-way street – it can’t be reversed. And yet, it’s been widely reported that scientists have done just that using quantum computing. So have they really?
Unfortunately not. But the work of the researchers from Moscow, the US and Switzerland is certainly intriguing – they’ve produced a series of papers on the possibility of breaking the second law of thermodynamics. The law states that a system will either remain static or degenerate into a more disordered state; it will never become more ordered. Billiard balls will not roll back into a pyramid, tea will not flow back into the tea bag, a volcano will not unerupt. These things are only possible with outside intervention – the billiard balls are only going to move back if you put them back.
“That law is closely related to the notion of the arrow of time that posits the one-way direction of time from the past to the future,” the study’s lead author, Gordey Lesovik, who heads the institute’s Laboratory of the Physics of Quantum Information Technology, told the Science X news website. In other words, if you can violate that law, can you also violate the law that says time only moves forwards?
In the experiments, conducted using an IBM quantum computer, the scientists used two or three qubits to model the behaviour of an electron. A qubit is the basic unit of quantum computing, working in the same way as a binary bit in a traditional computer.
Under quantum theory, an electron can be in more than one place at once. A formula called Schrodinger’s equation (he of the famous cat) holds that the number of places the electron can be in increases over time – in other words, its location becomes more imprecise. The scientists aimed to model a reversal of this process – so the electron’s location would become more precise.
The qubits were ordered and then put into disarray – and then the scientists used their program to try to reverse the situation. After running their experiment 8,192 times, they found that this happened in 85 percent of cases when two qubits were used, but just 49 percent of cases when three qubits were used.
So no, this isn’t a reversal of time, which was still ticking on. However, the scientists hope the algorithms they used could be used to make quantum computer programs more accurate.
The researchers – from the Moscow Institute of Physics and Technology, the Argonne National Laboratory in Illinois, and the Institute of Theoretical Physics at ETH Zurich university – published their work in the open access peer-reviewed journal Scientific Reports last month. Supporters of the work included the US Department of Energy, the Swiss National Foundation (a government organisation supporting scientific research), and the Russian Foundation for Basic Research.
You don’t have to be turning back time to be eligible for government funding through the R and D tax credit scheme. Companies whose work involves scientific, technological or medical research can apply to the scheme, which gives you some of your tax back to help you cover your costs. At R&D Tax Solutions, we specialise in helping companies make successful claims. Have a look at our page on how to calculate R&D tax credits to find out more – and call us on 0161 298 1010 to see how we can help.