Can Quantum Physics Explain Consciousness?

A new approach to a once-farfetched theory is making it plausible that the brain functions like a quantum computer.

.. Over the past decade, however, growing evidence suggests that certain biological systems might employ quantum mechanics. In photosynthesis, for example, quantum effects help plants turn sunlight into fuel. Scientists have also proposedthat migratory birds have a “quantum compass” enabling them to exploit Earth’s magnetic fields for navigation, or that the human sense of smell could be rooted in quantum mechanics.

.. Fisher has rephrased the central question—is quantum processing happening in the brain?—in such a way that it lays out a road map to test the hypothesis rigorously.

.. Since nearly all psychiatric medications are complicated molecules, he focused on one of the most simple, lithium, which is just one atom—a spherical cow, so to speak, that would be an easier model to study than Prozac, for instance. The analogy is particularly appropriate because a lithium atom is a sphere of electrons surrounding the nucleus, Fisher said. He zeroed in on the fact that the lithium available by prescription from your local pharmacy is mostly a common isotope called lithium-7. Would a different isotope, like the much more rare lithium-6, produce the same results?

.. Over the course of his five-year quest, Fisher has identified just one credible candidate for storing quantum information in the brain: phosphorus atoms

.. Others see no need to invoke quantum processing to explain brain function. “The evidence is building up that we can explain everything interesting about the mind in terms of interactions of neurons,” said Paul Thagard, a neurophilosopher at the University of Waterloo in Ontario, Canada

Quantum Hanky-Panky: A Conversation With Seth Lloyd

it has become clear over the last decade that photosynthesis—where a particle of light comes in from the sun, is absorbed by a chlorophyll molecule, the energy rattles around inside a leaf and gets turned into more leaves—is operating in a very quantum mechanical fashion.

Exactly the same kinds of models that we use to look at quantum computation allow us to understand what’s happening in photosynthesis. It turns out that photosynthetic plants, bacteria, and algae are extremely sophisticated in the way they use quantum mechanics. They use quantum coherence and funky effects like entanglement to get very high efficiency of energy transport.

.. Indeed, what’s happening in quantum information and quantum computing is it’s become more and more clear that quantum information is a universal language for how nature behaves.

.. this centerfold showed which parts of physics were talking with other parts of physics, who in this field was talking with this other field. They had to put quantum information right in the middle because everybody was talking with the people in quantum information.

.. by using ideas from quantum information, we’ve constructed systems that are much better than even the most efficient, naturally occurring system.

.. Twenty years ago, I wrote the first algorithms for how you could program the quantum computers we have now to explore how their quantum systems behave.

.. If you want to find out what happens when you send a photon a few billionths of second backwards in time and have a try to kill its former self, well, we have experiment that tests to see what happens when you do that.

.. It also turns out that quantum computers can detect and identify patterns that are very hard for a classical computer to detect. For example, if you have a huge dataset like the tick-by-tick history of all the stocks in the Dow Jones over the last fifty years, it’s a big dataset.

If you say, “I’d like to process this to find out what a good portfolio would be for me if I can tolerate a certain amount of risk and I want to have a certain amount of return.” Well, with a pretty small quantum computer, the kind that we’re going to have in the next five years or so, you could find the answer to that question much more accurately then you could do on a classical computer.

.. I, myself, am a theorist, so the experimentalists don’t like me to use a screwdriver in their lab because I tend to break things

.. Quantum computers are still at the stage where we have a small number of bits—10 bits that we can use, soon 50 bits, 100 quantum bits that we can use. Even though this is piddling by comparison with the classical computer, because quantum computers for specific problems are so much more powerful than classic computers

.. Lockheed Martin has bought a D‑Wave computer, Google and NASA have bought them, the Army is buying some of them.

.. I’ve been working with the folks at D-Wave to try to figure out why they are successful when they shouldn’t be. Ever since then, I patent everything by the way, even if I don’t know whether it’s going to work or not.

.. The strategy I’ve learned is that there’re a huge number of technologies out there, and we don’t have to adopt them. You don’t have to adopt these technologies.

You can use the ones that you like. You can not use the ones that you don’t like. I don’t use Facebook or Twitter or other social media, because I feel that there’s presence and there’s absence, and then there’s cyberpresence, and cyberpresence is a heck of a lot closer to absence than it is to actual presence.

.. DARPA was the first funding agency to recognize that this role of quantum mechanics in photosynthesis was a very important thing. They created the first program to fund looking at funky effects like quantum coherence and entanglement in photosynthesis and in energy transport.

.. The largest group or concentration of people working on quantum computation are in Canada at the Institute for Quantum Computing, in Waterloo

.. He had this intuition, and he came up with a formal notion of a quantum computer. But for more than five years or so, he couldn’t come up with something where it could do better.

Then when he finally came up with something, he showed where a classical computer takes two or three steps on average to this problem, a quantum computer can do it in one.

 

Andrew Briggs recommends the best books on Nature of Reality

It specifically tested the following statement of reality, which involves the conjunction of two postulates. One is that if you have a system that can be in one of two states, that at any given time it’s in one of those states. So either you’re in Oxford or you’re in Cambridge, but not both at the same time. The other is that you can find out which it is without affecting the subsequent history of the state, or in fact the previous history of the state. That’s called a non-invasive measurement. And the experiment we did showed that both of those could not, at the same time, be true.

.. So what these experiments are beginning to do is to take some of these candidate interpretations of reality, within the context of quantum theory, and make some progress in which of them you can and cannot believe.

.. So, for example, some of the experiments we’re doing now may lead to information communication technologies that use much less electricity than current technologies do. At the moment, information and communication technology uses about 5% of the world’s electricity. It’s only 5% but it’s 5% of a very big number. The carbon emissions are similar to those produced by the whole world airline industry.

.. We already know, for example, that part of photosynthesis involves quantum interference, and there’s good evidence that the avian compass—bird navigation—may sometimes use quantum processes.

.. The amazing thing about that is that unlike Deep Blue, which 20 years or so ago was programmed to play chess, AlphaGo was programmed to learn how to play Go.

.. I still am, at heart, a critical realist, but I now understand better what the problems are in thinking through that. I still think that, in practice, I do my science as if there is an objective reality to describe, but I do it with an awareness that the nature of that reality may be more subtle, and perhaps more interesting, than I’d at first thought.

.. My own motivation for the book was that as someone with a passion for science and a firm faith in God, I wanted to understand better how the science fits into the relationship. How does science fit into knowing God?

.. looking through the books you’ve chosen, the theme seems to be that the polarization of science and religion is not very helpful.

Indeed. Particularly when we get to what’s probably the most explicitly scholarly of all the books—The Territories of Science and Religion—we will see just how a very distinguished historian, Peter Harrison, has taken that to pieces.

.. ‘Suppose that nobody could have any children anymore. How then would we live? What would we live for? And what would our purpose be?’ She explores how different people would respond, and how different people would live in that situation.

.. There were very good reasons, in quantum theory, for not being able to do error correction in the way you can in a classical computer — namely that you can’t copy quantum information, you can’t have a quantum photocopier in the way you can for ordinary information. Andrew thought of a whole new way of overcoming that, which changed the field and made it feasible to have error correction.

.. Aren’t most scientists atheist? The data on American scientists seems to show that.

The scene in America is very different from the scene in Britain. There’s a very different history. In Britain we’ve got a very rich heritage of distinguished scientists who are people of strong Christian faith

.. the best surveys that have been done seem to indicate that a majority of elite scientists would describe themselves as spiritual persons. In science, there is a genuine pleasure from getting an experiment to work or developing a new technology, or solving a theoretical problem. That can be experienced by people whether or not they have a relationship with God. But I think what Andrew would say, and what I would say, is that that pleasure is hugely enriched when it’s in the context of a relationship with the Creator, whose work you’re studying.

.. Peter Harrison starts with (another) striking thought experiment, if you like. He says if a historian were to contend that he or she had discovered evidence of a hitherto unknown war that had broken out in the year 1600 between Israel and Egypt, what would your response be?

.. the 1600s, those territories didn’t exist with those designations. Of course the bits of land, the hills, the mountains existed, the topography existed, but not with those labels. What he is showing, in an immensely scholarly way, is that these labels of science and religion—although nowadays we think we know what they mean—are rather recent and no more applicable to most of intellectual and cultural history than the labels of Israel and Egypt would have been to those territories in 1600. And therefore a lot of misunderstandings arise because people are applying incorrect categories.

.. The idea of religion as a distinct body of knowledge is a surprisingly recent one,

.. In the 17th century, Rene Descartes defines scientia as the skill to solve every problem.

..

Religio, in the Middle Ages, was a virtue. It referred to internal acts of devotion and prayer. This interior dimension is more important than any outward expression—that’s according to Aquinas, in the 13th century. There is no sense in which religio refers to systems of proposition of beliefs, and no sense of different religions. They’re inner virtues.

.. And he wants to replace the ‘and’ with ‘of.’ He wants to talk about a theology of science.

.. the Book of Job. The book is worth it for that chapter alone. Job would have been a fantastic scientist. He didn’t have the mathematics that we have, he didn’t have the

God asks him well over 100 different questions about the material world—mainly the animal world, but not only. They’re all fabulous questions. In the context of these big ultimate questions Job is a very rich book.

.. He disagrees with probably the majority of commentators, who would say that what God says to Job out of the whirlwind does not answer Job’s questions. Tom McLeish faces that square on, he even disagrees with one of the leading scholars in the field, David Clines. But it’s not a one sentence, knockdown answer. And I don’t think these ultimate questions lend themselves to that. If you’re asking for an answer to the question, ‘Why do innocent people suffer?’ if someone said, ‘I can give you a one sentence, complete answer to that question,’ I would treat it with great scepticism. I don’t think it’s the sort of question that lends itself to a simple, formulaic answer.

.. the desire of science to maximise the benefit from the slipstream of ultimate questions, the temptation to get too close can be very strong. If the wheels do touch—by which I mean trying to make science answer religious questions or vice versa—then you can get a chute in which everyone falls over.

.. Although he was put on trial, he was never sent to jail. The issue was more about whether or not Galileo was allowed to teach these things.

.. It’s another thought experiment: What would happen if incontrovertible evidence was found of the human remains of Jesus in Jerusalem? i.e. a skeleton was found that could undoubtedly be identified as the Jesus of Nazareth who was crucified?

.. he does is to look at the responses of different individuals and different groups of people to the discovery that Jesus did not rise from the dead.

.. Deism, in this context, means a belief in a God who was responsible for the creation of the world, but has no further involvement in it. Theologians would say no revelation. The demise of deism was inherent in it, because you can’t relate to such a do-nothing god. It makes no sense to pray to him or anything like that.

.. His research career ended fairly soon after his doctorate. You won’t find many scholarly papers by him in peer reviewed international journals. But the public engagement of science is a hugely important activity and he started out his career absolutely brilliant at it.

.. If you’re going to engage in an argument with people that you disagree with—which is a healthy activity, at least at Oxford—you need to engage with the best and the strongest of their arguments and not the weakest of their arguments and still more not with a caricature of them.

.. Many people feel that his books have, as time has gone by, shouted louder and louder with weaker and weaker arguments. I don’t know of any scholar who takes the arguments in his more recent books at all seriously, except, perhaps, in one or two cases to counter them.

.. Actually my favourite answer to Richard Dawkins is by John Cornwell, who has written a lovely book entitled Darwin’s Angel: An Angelic Riposte to ‘The God Delusion.’ , in which the angel gives advice to Dawkins about how to think more clearly.