The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
MICHIO KAKU: Years ago, we physicists predicted the end of Moore's Law, which says a computer power doubles every 18 months. But we also, on the other hand, proposed a positive program—perhaps molecular computers, quantum computers can take over when silicon power is exhausted. In fact, already we see a slowing down of Moore's Law. Computer power simply cannot maintain its rapid exponential rise using standard silicon technology. The two basic problems are heat and leakage. That's the reason why the age of silicon will eventually come to a close. No one knows when, but as I mentioned we already now can see the slowing down of Moore's Law, and in 10 years it could flatten out completely. So what's the problem? The problem is that a Pentium chip today has a layer almost down to 20 atoms across, 20 atoms across. When that layer gets down to about five atoms across, it's all over. You have two effects, heat. The heat generated will be so intense that the chip will melt. You can literally fry an egg on top of the chip, and the chip itself begins to disintegrate. And second of all, leakage. You don't know where the electron is anymore. The quantum theory takes over. The Heisenberg Uncertainty Principle says you don't know where that electron is anymore, meaning it could be outside the wire, outside the Pentium chip or inside the Pentium chip. So there is an ultimate limit set by the laws of thermodynamics and set by the laws of quantum mechanics, as to how much computing power you can do with silicon.
VERN BROWNELL: I refer to today's computers as classical computers. They compute largely in the same way they have for the past 60 or 70 years, since John Von Neumann and others invented the first electronic computers back in the '40s. And we've had amazing progress over those years. Think of all the developments there've been on the hardware side and the software side over those 60 or 70 years and how much energy and development has been put into those areas. And we've achieved marvelous things with that classical computing environment, but it has its limits too, and people sometimes ask, "Why would we need any more powerful computers?" These applications, these problems that we're trying to solve, are incredibly hard problems and aren't well-suited for the architecture of classical computing. So I see quantum computing as another set of tools, another set of resources for scientists, researchers, computer scientists, programmers, to develop and enhance some of these capabilities to really change the world in a much better way than we're able to today with classical computers.
BRIAN GREENE: A quantum computer is a device, a technological device that in principle would harness the full capacity of quantum mechanics, to undertake calculations that a standard computer would be absolutely unable to achieve. One way of thinking about it is this. There's an approach to quantum mechanics where one imagines that there are many, in some sense, parallel realities moving along in some larger environment, if you will, where, for instance, if I want to measure an electron, quantum theory says, well, there's a 50% chance it's there and a 50% chance it's over there, and then what does that mean? Well, one interpretation says, well, there are actually two universes, and in one universe the electron is here and in another universe it is over there. That's a crazy-sounding idea, but a quantum computer perhaps can harness that by doing some calculations over here and other calculations over there in parallel. Now, it's doing, in some sense, twice as many calculations as a classical computer existing in one world would be able to do. Now, imagine taking that idea and spreading it over all of the possible realities allowed by quantum mechanics. Now, you're harnessing all of these different worlds if you will, to do all of these calculations in parallel much faster, much more powerful, doing calculations that in a single universe would be impossible.
LAWRENCE KRAUSS: Let me briefly describe the difference between a quantum computer and a regular computer at some level. In a regular computer, you've got ones and zeros, which you store in binary form and you manipulate them. Let's say you have an elementary particle that's spinning. If it's spinning, we say it's spinning, it's pointing up or down, depending upon whether it's spinning this way or this way pointing up or down. And so I could store the information by having lots of particles and some of them spinning up and some of them spinning down, right? Ones and zeros. But in the quantum world, it turns out that particles like electrons are actually spinning in all directions at the same time, one of the weird aspects of quantum mechanics. We may measure by doing a measurement of an electron, find it spinning this way. But before we did the measurement, it was spinning this way and this way and that way and that way all at the same time. Sounds crazy, but true. Now, that means if the electron is spinning in many different directions at the same time, if we don't actually measure it, it can be doing many computations at the same time. And so a quantum computer is based on manipulating the state of particles like electrons so that during the calculation, many different calculations are being performed at the same time, and only making a measurement at the end of the computation. So we exploit that fact of quantum mechanics that particles can do many things at the same time to do many computations at the same time, and that's what would make a quantum computer so powerful.
BRAD TEMPLETON: The rules of quantum mechanics are rather strange and not very intuitive to us, and so they don't act like the higher-level rules that we've built computers on so far. So there's a bunch of research to study whether or not you can do things in quantum mechanics that perform computation in ways that we can't do at the level of mechanical systems or electronic systems that we use. In particular, it seems possible in theory to do very, very huge amounts of computing in quantum mechanics, sort of as some people would imagine it as though you were tapping into millions and trillions and billions of parallel universes and having computation take place in all of those parallel universes until an answer is found in one and is revealed to you in your universe. There are people who believe that they can make a computer that uses these properties of quantum computing to solve some very, very specific problems much, much faster than the way we solve them there with computers. And when I say much, much faster, so much faster that if you were to turn the entire universe into an ordinary computer like the one on your desk, it still could not out-compete the quantum computer at solving these problems.
MICHIO KAKU: Now, quantum computing in some sense is the ultimate computer, but there are enormous problems with quantum computing. The main problem is decoherence. Let's say I have two atoms and they vibrate in unison. If I have two atoms that vibrate in unison, I can shine a light wave and flip one over and do a calculation, but they have to first start vibrating in unison. Eventually, an airplane goes over; eventually, a child walks in front of your apparatus; eventually, somebody coughs, and then all of a sudden they're no longer in synchronization. It gets contaminated by disturbances from the outside world. Once you lose the coherence the computer is useless.
LAWRENCE KRAUSS: In order to have a quantum mechanical state where you can distinctly utilize and exploit those weird quantum properties, in some sense, you have to isolate that system from all of its environment, because if it interacts with the environment, the quantum mechanical weirdness sort of washes away, and that's the problem with a quantum computer. You wanna make this microscopic object, you wanna keep it behaving quantum mechanically which means isolating it very carefully from within itself, all the interactions and the outside world, and that's the hard part, is isolating things enough to maintain this what's called quantum coherence.
VERN BROWNELL: You need to create a very quiet, clean, cold environment for these chips to work in. And ultimately what we're building is a quantum computer on a chip that's about the size of your fingernail in this very exotic environment. So that environment runs at near absolute zero. So absolute zero, as you know, is the lowest temperature possible in the universe, it's so-called zero degrees Kelvin. So these machines run at a very low temperature so that they can have that pristine, very clean, quiet environment to run in, it doesn't disturb that quantum computation. And in fact, it runs down at what's called 10 milliKelvin, which is 0.01 Kelvin. Absolute zero is zero degrees Kelvin. So this is running at minus 273.14 degrees C, and the lowest possible temperature in physics is minus 273.15 degrees C. So very, very cold, very, very rarefied environments, because we also running in effectively a magnetic vacuum. So you could consider these environments, these rigs that we've built, these systems that we've built, to be probably the most rarefied environments in the universe unless there's other intelligent life in the universe that has, you know pure, colder environments. For instance, outer space is 150 times warmer than the environment that we build for these quantum computations.
So you may ask why do we go through all this trouble? The answer is the promise of quantum computing is exponential speed-ups over classical computing for a particular set of problems. And that's very important and exciting to researchers who are working on human-scale problems ranging from things like developing drugs for cancer or better modeling the molecular interactions of cancer and how it attacks cells and things like that, to big data analysis, looking for patterns and inferences and drawing insight from large amounts of data, or doing things like better modeling financial services markets and better managing risk and so on. So these are all kinds of applications that aren't particularly well-suited by today's type of computers, and it's not a replacement for classical computing. It will be used in what I would call a hybrid approach, where you're gonna see both the capability that's already been built in the high-performance computing and other types of computing markets working very closely with quantum computing resources.
- While today's computers—referred to as classical computers—continue to become more and more powerful, there is a ceiling to their advancement due to the physical limits of the materials used to make them. Quantum computing allows physicists and researchers to exponentially increase computation power, harnessing potential parallel realities to do so.
- Quantum computer chips are astoundingly small, about the size of a fingernail. Scientists have to not only build the computer itself but also the ultra-protected environment in which they operate. Total isolation is required to eliminate vibrations and other external influences on synchronized atoms; if the atoms become 'decoherent' the quantum computer cannot function.
- "You need to create a very quiet, clean, cold environment for these chips to work in," says quantum computing expert Vern Brownell. The coldest temperature possible in physics is -273.15 degrees C. The rooms required for quantum computing are -273.14 degrees C, which is 150 times colder than outer space. It is complex and mind-boggling work, but the potential for computation that harnesses the power of parallel universes is worth the chase.
- 3 ways quantum computing can help us fight climate change - Big ... ›
- Lawrence Krauss: Quantum Computing Explained - Big Think ›
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Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>
The vagus nerve<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />
Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>
The future of bioelectronic medicine<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />
Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>
"The Expanse" is the best vision I've ever seen of a space-faring future that may be just a few generations away.
- Want three reasons why that headline is justified? Characters and acting, universe building, and science.
- For those who don't know, "The Expanse" is a series that's run on SyFy and Amazon Prime set about 200 years in the future in a mostly settled solar system with three waring factions: Earth, Mars, and Belters.
- No other show I know of manages to use real science so adeptly in the service of its story and its grand universe building.
Credit: "The Expanse" / Syfy<p>Now, I get it if you don't agree with me. I love "Star Trek" and I thought "Battlestar Galactica" (the new one) was amazing and I do adore "The Mandalorian". They are all fun and important and worth watching and thinking about. And maybe you love them more than anything else. But when you sum up the acting, the universe building, and the use of real science where it matters, I think nothing can beat "The Expanse". And with a <a href="https://www.rottentomatoes.com/tv/the_expanse" target="_blank">Rotten Tomato</a> average rating of 93%, I'm clearly not the only one who feels this way.</p><p>Best.</p><p>Show.</p><p>Ever. </p>
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The first rule of Vulture Club: stay out of Portugal.
So you're a vulture, riding the thermals that rise up over Iberia. Your way of life is ancient, ruled by needs and instincts that are way older than the human civilization that has overtaken the peninsula below, and the entire planet.
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- Here are 10 actions the world can take to strengthen and preserve our oceans for generations to come.