09/05/2022 02:24

Where quantum physics and life meet

  • Blog Fundamental Science

Strange microworld phenomena can reverberate in nodes, says quantum biology

Art: Julia Jabur

By Clarice Cudischevitch

It is common for quantum physics to be described as “counterintuitive.” And it is no wonder: after all, a theory that speaks of atoms that pass through “walls” like ghosts, distant particles that communicate as if by telepathy, and elements that exist in more than one place at the same time, inconsistent with the laws of classical physics that we know, sounds at the very least strange. Many scientists consider, however, that its oddities are restricted to the microscopic world – that of atoms, electrons and protons – but that they do not affect the visible world of large and living things. Yet, this is not what a relatively new area of science says: quantum biology.

There is a caveat. When we talk about atoms passing through “walls” (more precisely, the phenomenon known as the tunnel effect), particles that communicate by “telepathy” (quantum entanglement) and objects capable of being in more than one state at the same time (superposition), this has nothing to do with supernatural phenomena. In fact, the term “quantum” has been favored by mystics, but practices such as “quantum therapy” and “quantum diet” are not scientific and have no relationship with actual quantum physics.

Well then, what “quantum biologists” (in truth, there is still no official name for scholars in the field) believe is that the phenomena that occur in the microworld and are described by quantum physics do have consequences in the macroscopic world, governed by laws of classical Newtonian physics. More specifically, they have consequences in the living world, leaving a “quantum signature” in it.

The reader may ask: is this not obvious? If we are all made of atoms, it is expected that what happens in the microscopic world would have an impact on the world we can see. “Biology is, after all, a kind of applied chemistry, and chemistry is a kind of applied physics. So isn’t everything […] just physics when you really get down to the fundamentals?,” ask rhetorically the molecular genetics professor Johnjoe McFadden and the theoretical physicist Jim Al-Khalili in the book “Life on the Edge: The Coming of Age of Quantum Biology” from 2014.

And it is true. If biology ultimately involves the interaction between atoms, then the rules of the quantum world must, in fact, operate at the smallest scales of living organisms, the authors claim. However, what science has said thus far is that these rules operate only at these scales but do not generate relevant effects on the world we see. We do not pass through walls nor can we be in two places at the same time, even though the particles within us are capable of it. Why is there this boundary between the visible universe and the universe that we know exists in the smallest scales?

The evidence in favor of quantum biology indicates that quantum phenomena cross this boundary and not only generate an impact on the living world, but this impact is not trivial. There are indications of quantum phenomena such as superposition and tunneling in various biological processes, from photosynthesis to enzyme action. A study published in Nature in 2004 showed that the robin migrates around the planet, as if its retina “uses” quantum entanglement between electrons to guide it using the Earth’s magnetic field. The bird, in fact, ended up becoming the poster child of quantum biology.

There is no irrefutable proof that quantum biology does not exist, and that is enough for science. The problem is that we also do not have instruments with sufficient technology to obtain the irrefutable proof that it exists. This is because measurement is one of the greatest challenges of quantum physics. We know that quantum objects do strange things, but the moment we observe them, they lose this character and begin to behave like any classical object, that is, governed by the rules of classical physics. Submitting a quantum property to a scientific instrument, such as pointing in many directions simultaneously, implies transforming it into a conventional property – pointing in a single direction.

The Brazilian quantum engineer Clarice Aiello, 39, leads the Center for Quantum Biology at the University of California, Los Angeles (UCLA). Her objective is to use quantum physics technologies to build instruments that allow quantum experimentation and measurement in biology. “When quantum objects begin to interact with each other, there is an uncontrolled reaction that kills this quantum character,” she explains. “Everything that begins quantum dies classical. That is why we live in a classical world. This is where the discomfort that quantum mechanics causes us comes from.”

As it is easy to kill this quantum character in any object, the challenge of engineering is to find ways to protect the quantum system as much as possible. This includes, for example, keeping quantum chips at very low temperatures to decrease the thermal energy of interaction and using vacuum chambers to prevent collisions between atoms. “Even the most perfect quantum computer will die classically. It will only give us quantum information before the time of thermalization and loss of its quantum character,” says Aiello.

Therefore, quantum biology can also be confusing by proposing that quantum phenomena are happening at room temperature and with important consequences for the biological functioning of things. “Although, in biology, this quantum character also ends up being ‘pulled’ by classical behavior in a very short time, quantum phenomena can still have an influence and change biological systems,” highlights the engineer.

It is worth noting that a short time, in the quantum world, is very short. For example, in the case of energy capture from the sun by plants in the process of photosynthesis, this time is on the order of a picosecond, which is equivalent to 10-12 seconds, or one trillionth of a second. In the case of the quantum property studied by Aiello, electron spin, things are slower – they take from one billionth to one millionth of a second. “That is, if the quantum phenomena actually happen there, this means that quantum biology can survive for a microsecond – which, believe me, is enough to macroscopically alter, for example, chemical reactions.”

For the scientist, there is no doubt that quantum phenomena have an influence on the living world, whether in cell culture, drosophila or the chipmunk that visits her daily on her porch and that appeared when we spoke over video call. Many experiments have already been performed on a chemical scale in protein solutions, and quantum phenomena were present there. “The next step is confirmation in a behavioral experiment, and there is a large difference between a protein and a drosophila.”

In practice, Aiello’s work involves lying down and crawling on the ground to build something that does not exist anywhere in the world, a kind of microscope with coils – very different from the microscopes that we usually see in biology laboratories. “It is a large optical table with a lot of mirrors and lasers, which has the function of helping us look inside a cell. Around the biological sample, we placed coils that are the source of the magnetic field. Our idea is to look at what happens in the cell and control it by changing the magnetic field.”

It is a risky bet, but it can be revolutionary. Aiello believes that quantum biology is today where quantum computing was 20 years ago, and currently, no one doubts its potential. “Everyone is starting from scratch, which is a great opportunity for Brazil,” emphasizes the engineer, who established a partnership with the D’Or Institute for Research and Education (IDOR) to develop the field in the country. “We need to train interdisciplinary scientists to work in this field today and plan where we want to be in the future.”

And, although for Aiello everything that seems to be magic is unexplained science, it does not rule out the possibility that in the distant future, we can speak of “quantum healing” – not in the esoteric sense. “If we understand how quantum phenomena affect chemical reactions in the body, perhaps in about 50 years we will be able to direct them to treat diseases, in the same way that medicines do but by controlling endogenous quantum behavior (that is, without requiring genetic manipulation) that seems to exist in living beings. Today, however, this is only science fiction.”

For now, what we have are many fundamental questions and, according to McFadden and Al-Khalili, “the mystery of how quantum weirdness manages to survive in hot, wet and messy living bodies.”

This text was originally publicated on Serrapilheira’s Ciência Fundamental blog on Folha de S.Paulo

  • Topics
  • “Life on the Edge: The Coming of Age of Quantum Biology
  • quantum biology