Note — Sep 15, 2019

An Important Quantum Algorithm May Actually Be a Property of Nature

Seen in → No.94

Source → technologyreview.com/s/614259/an-important-...

This is your mind-blowing (expanding?) read for the week. In 1996 the physicist Lov Grover came up with a quantum algorithm to greatly reduce the time required for searching through a database of N entries. Since then there havent been computers powerful enough to actually implement the algorithm. Now Stéphane Guillet and colleagues at the University of Toulon in France say they have evidence that “under certain conditions, electrons may naturally behave like a Grover search, looking for defects in a material.” I’m not going to try to simply this accurately, read the article, but super quickly; they tested electrons “walking” paths on triangular and square grids, and the electrons naturally implement Grover searches in doing so. The bigger 🤯 is that the same algorithm would also fit DNA research by Apoorva Patel at the Indian Institute of Science in Bangalore and explain why there are four nucleotide bases and twenty amino acids in DNA (see second to last quote below).

[C]hallenges involved. The first quantum computer capable of implementing it appeared in 1998, but the first scalable version didn’t appear until 2017, and even then it worked with only three qubits. So new ways to implement the algorithm are desperately needed. […]

The team focused on simulating the way a Grover search works for electrons exploring triangular and square grids, but they also included other physically realistic effects, such as defects in the grid in the form of holes, and quantum properties such as interference effects. […]

In other words, if the search processes involved in assembling DNA and proteins is to be as efficient as possible, the number of bases should be four and the number of amino acids should to be 20—exactly as is found. The only caveat is that the searches must be quantum in nature. […]

Since then, an increasing body of evidence has emerged that quantum processes play an important role in a number of biological mechanisms. Photosynthesis, for example, is now thought to be an essentially quantum process.