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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It could lead to a massive uptake in those previously hesitant.
A financial shot in the arm could be just what is needed for Americans unsure about vaccination.
On May 12, 2021, the Republican governor of Ohio, Mike DeWine, announced five US$1 million lottery prizes for those who are vaccinated. Meanwhile, in West Virginia, younger citizens are being enticed to get the shot with $100 savings bonds, and a state university in North Carolina is offering students who get vaccinated a chance to win the cost of housing. Many companies are paying vaccinated employees more money through bonuses or extra paid time off.
The push to get as many people vaccinated as possible is laudable and may well work. But leading behavioral scientists are worried that paying people to vaccinate could backfire if it makes people more skeptical of the shots. And ethicists have argued that it would be wrong, citing concerns over fairness and equity.
As a behavioral scientist and ethicist, I draw on an extensive body of research to help answer these questions. It suggests that incentives might work to save lives and, if properly structured, need not trample individual rights or be a huge expense for the government.
In the United States, incentives and disincentives are already used in health care. The U.S. system of privatized health insurance exposes patients to substantial deductibles and copays, not only to cover costs but to cut down on what could be deemed as wasteful health care – the thinking being that putting a cost to an emergency room visit, for example, might deter those who aren't really in need of that level of care.
In practice, this means patients are encouraged to decline both emergency and more routine care, since both are exposed to costs.
Paying for health behaviors
In the case of COVID-19, the vaccines are already free to consumers, which has undoubtedly encouraged people to be immunized. Studies have shown that reducing out-of-pocket costs can improve adherence to life-sustaining drugs, whether to prevent heart attacks or to manage diabetes.
A payment to take a drug goes one step further than simply reducing costs. And if properly designed, such incentives can change health behaviors.
And for vaccination in particular, payments have been successful for human papillomavirus (HPV) in England; hepatitis B in the United States and the United Kingdom; and tetanus toxoid in Nigeria. The effects can be substantial: For example, for one group in the HPV study, the vaccination rate more than doubled with an incentive.
For COVID-19, there are no field studies to date, but several survey experiments, including one my group conducted with 1,000 Americans, find that incentives are likely to work. In our case, the incentive of a tax break was enough to encourage those hesitant about vaccinations to say they would take the shot.
Even if incentives will save lives by increasing vaccinations, there are still other ethical considerations. A key concern is protecting the autonomous choices of people to decide what they put into their own bodies. This may be especially important for the COVID-19 vaccines, which – although authorized as likely safe and effective – are not yet fully approved by the Food and Drug Administration.
But already people are often paid to participate in clinical trials for drugs that have not yet been approved by the FDA. Ethicists have worried that such payments may be “coercive" if the money is so attractive as to override a person's free choices or make them worse off overall.
One can quibble about whether the term “coercion" applies to offers of payment. But even if offers were coercive, payments may still be reasonable to save lives in a pandemic if they succeed in greater levels of immunization.
During the smallpox epidemic nearly 100 years ago, the U.S. Supreme Court upheld the power of states to mandate vaccines. Compared with mandating vaccination, the incentives to encourage vaccines seem innocuous.
Exploitation and paternalism
Yet some still worry. Bioethicists Emily Largent and Franklin Miller wrote in a recent paper that a payment might “unfairly" exploit “those U.S. residents who have lost jobs … or slipped into poverty during the pandemic," which could leave them feeling as if they have “no choice but to be vaccinated for cash." Others have noted that vaccine hesitancy is higher in nonwhite communities, where incomes tend to be lower, as is trust in the medical establishment.
Ethicists and policymakers should indeed focus on the poorest members of our community and seek to minimize racial disparities in both health outcomes and wealth. But there is no evidence that offering money is actually detrimental to such populations. Receiving money is a good thing. To suggest that we have to protect adults by denying them offers of money may come across as paternalism.
Some ethicists also argue that the money is better spent elsewhere to increase participation. States could spend the money making sure vaccines are convenient to everyone, for example, by bringing them to community events and churches. Money could also support various efforts to fight misinformation and communicate the importance of getting the shot.
The cost of incentives
Financial incentives could be expensive as a policy solution. As in Ohio, lottery drawings are one way to cap the overall cost of incentives while giving millions of people an additional reason to get their shot.
The tax code could also allow for a no-cost incentive for vaccination. Tax deductions and credits are often designed to encourage behaviors, such as savings or home ownership. Some states now have big budget surpluses and are considering tax relief measures. If a state announced now that such payments would be conditional on being vaccinated, then each person declining the shot would save the government money.
Ultimately, a well-designed vaccination incentive can help save lives and need not keep the ethicists up at night.
Geologists discover a rhythm to major geologic events.
- It appears that Earth has a geologic "pulse," with clusters of major events occurring every 27.5 million years.
- Working with the most accurate dating methods available, the authors of the study constructed a new history of the last 260 million years.
- Exactly why these cycles occur remains unknown, but there are some interesting theories.
Our hearts beat at a resting rate of 60 to 100 beats per minute. Lots of other things pulse, too. The colors we see and the pitches we hear, for example, are due to the different wave frequencies ("pulses") of light and sound waves.
Now, a study in the journal Geoscience Frontiers finds that Earth itself has a pulse, with one "beat" every 27.5 million years. That's the rate at which major geological events have been occurring as far back as geologists can tell.
A planetary calendar has 10 dates in red
Credit: Jagoush / Adobe Stock
According to lead author and geologist Michael Rampino of New York University's Department of Biology, "Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geologic events are correlated and not random."
The new study is not the first time that there's been a suggestion of a planetary geologic cycle, but it's only with recent refinements in radioisotopic dating techniques that there's evidence supporting the theory. The authors of the study collected the latest, best dating for 89 known geologic events over the last 260 million years:
- 29 sea level fluctuations
- 12 marine extinctions
- 9 land-based extinctions
- 10 periods of low ocean oxygenation
- 13 gigantic flood basalt volcanic eruptions
- 8 changes in the rate of seafloor spread
- 8 times there were global pulsations in interplate magmatism
The dates provided the scientists a new timetable of Earth's geologic history.
Tick, tick, boom
Credit: New York University
Putting all the events together, the scientists performed a series of statistical analyses that revealed that events tend to cluster around 10 different dates, with peak activity occurring every 27.5 million years. Between the ten busy periods, the number of events dropped sharply, approaching zero.
Perhaps the most fascinating question that remains unanswered for now is exactly why this is happening. The authors of the study suggest two possibilities:
"The correlations and cyclicity seen in the geologic episodes may be entirely a function of global internal Earth dynamics affecting global tectonics and climate, but similar cycles in the Earth's orbit in the Solar System and in the Galaxy might be pacing these events. Whatever the origins of these cyclical episodes, their occurrences support the case for a largely periodic, coordinated, and intermittently catastrophic geologic record, which is quite different from the views held by most geologists."
Assuming the researchers' calculations are at least roughly correct — the authors note that different statistical formulas may result in further refinement of their conclusions — there's no need to worry that we're about to be thumped by another planetary heartbeat. The last occurred some seven million years ago, meaning the next won't happen for about another 20 million years.
The father of all giant sea bugs was recently discovered off the coast of Java.
- A new species of isopod with a resemblance to a certain Sith lord was just discovered.
- It is the first known giant isopod from the Indian Ocean.
- The finding extends the list of giant isopods even further.
Humanity knows surprisingly little about the ocean depths. An often-repeated bit of evidence for this is the fact that humanity has done a better job mapping the surface of Mars than the bottom of the sea. The creatures we find lurking in the watery abyss often surprise even the most dedicated researchers with their unique features and bizarre behavior.
A recent expedition off the coast of Java discovered a new isopod species remarkable for its size and resemblance to Darth Vader.
The ocean depths are home to many creatures that some consider to be unnatural.
According to LiveScience, the Bathynomus genus is sometimes referred to as "Darth Vader of the Seas" because the crustaceans are shaped like the character's menacing helmet. Deemed Bathynomus raksasa ("raksasa" meaning "giant" in Indonesian), this cockroach-like creature can grow to over 30 cm (12 inches). It is one of several known species of giant ocean-going isopod. Like the other members of its order, it has compound eyes, seven body segments, two pairs of antennae, and four sets of jaws.
The incredible size of this species is likely a result of deep-sea gigantism. This is the tendency for creatures that inhabit deeper parts of the ocean to be much larger than closely related species that live in shallower waters. B. raksasa appears to make its home between 950 and 1,260 meters (3,117 and 4,134 ft) below sea level.
Perhaps fittingly for a creature so creepy looking, that is the lower sections of what is commonly called The Twilight Zone, named for the lack of light available at such depths.
It isn't the only giant isopod, far from it. Other species of ocean-going isopod can get up to 50 cm long (20 inches) and also look like they came out of a nightmare. These are the unusual ones, though. Most of the time, isopods stay at much more reasonable sizes.
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During an expedition, there are some animals which you find unexpectedly, while there are others that you hope to find. One of the animal that we hoped to find was a deep sea cockroach affectionately known as Darth Vader Isopod. The staff on our expedition team could not contain their excitement when they finally saw one, holding it triumphantly in the air! #SJADES2018
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What benefit does this find have for science? And is it as evil as it looks?
The discovery of a new species is always a cause for celebration in zoology. That this is the discovery of an animal that inhabits the deeps of the sea, one of the least explored areas humans can get to, is the icing on the cake.
Helen Wong of the National University of Singapore, who co-authored the species' description, explained the importance of the discovery:
"The identification of this new species is an indication of just how little we know about the oceans. There is certainly more for us to explore in terms of biodiversity in the deep sea of our region."
The animal's visual similarity to Darth Vader is a result of its compound eyes and the curious shape of its head. However, given the location of its discovery, the bottom of the remote seas, it may be associated with all manner of horrifically evil Elder Things and Great Old Ones.
Researchers discovered a galactic wind from a supermassive black hole that sheds light on the evolution of galaxies.
- A new study finds the oldest galactic wind yet detected, from 13.1 billion years ago.
- The research confirms the theory that black holes and galaxies evolve together.
- The galactic wind was spotted using the Atacama Large Millimeter/submillimeter Array in Chile.
An enormously powerful galactic wind generated by a supermassive black hole 13.1 billions years ago has been discovered by researchers. The scientists used the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, which combines 66 radio telescopes, to make the find. The results are published in the Astrophysical Journal.
This is the earliest example of this type of wind yet spotted that underscores the role of black holes in the formation of galaxies. Research has shown that galactic winds affect redistribution of metals around the galaxy and impact start formation.
Black holes and galaxies evolve together
In previous studies, scientists have noticed an unexpected proportional relationship between the mass of a supermassive black hole at the center of a large galaxy, which can grow up to billions of times more massive than the sun, and the mass of the galaxy's central area (known as a "bulge"). The proportionality of the masses is especially unusual considering that galaxies and black holes are so different in size, with the bulge generally being orders of magnitude larger. This led the researchers to conclude that galaxies and black holes developed together through coevolution, which involved some physical interaction courtesy of the galactic wind.
As ALMA's press release explains, a galactic wind starts coming into existence when a supermassive black hole gobbles up giant quantities of matter. It is then moved at such a high speed by the black hole's gravity that it radiates intense energy, which in turn, pushes surrounding matter away, creating the galactic wind.
Takuma Izumi, the paper's lead author and a researcher at the National Astronomical Observatory of Japan (NAOJ), says an important question is: "When did galactic winds come into existence in the universe?" Finding this out can lead to understanding how galaxies and supermassive black holes coevolved.
Finding an ancient galactic wind
The researchers used NAOJ's Subaru Telescope to locate over 100 galaxies that existed more than 13 billion years ago that featured supermassive black holes. They then used the high sensitivity of ALMA to analyze the gas motion in these galaxies, finding that the dust and carbon of one of them (dubbed J1243+0100) emitted radio waves. This allowed the scientists to detect the presence of an intense galactic wind that rushes forth from the supermassive black hole at about 1,118,468 miles per hour (500 km/second). The energy of the wind, the oldest found so far, is so strong that it pushes away stellar materials, preventing stars from forming.
Interestingly, the mass of the bulge in J1243+0100 was found to be about 30 billion times larger than that of the sun, while the mass of the galaxy's supermassive black hole was estimated to be about 1 percent of that. This ratio is essentially the same as the mass ratio of black holes to galaxies in today's universe. To the scientists, this demonstrates how essential black holes are in affecting the growth of galaxies, supporting the notion of coevolution from the early period of the universe.
"Our observations support recent high-precision computer simulations which have predicted that coevolutionary relationships were in place even at about 13 billion years ago," explained Izumi.
The scientists are planning to observe a large pool of space objects in the future, with the goal of clarifying "whether or not the primordial coevolution seen in this object is an accurate picture of the general universe at that time," further commented Izumi.