Category Archives: Quantum Physics

Heterostructures are different layers of atoms stacked on top of each other to form a single structure. They were first proposed in 1959 by the physicist Richard Feynman, who famously asked: What would the properties of materials be if we could arrange atoms just the way we want them?

Over the following decades, researchers developed the ability to engineer the arrangement of atoms through which particles such as electrons (particles of charge) or photons (particles of light) travel.

This allowed scientists to probe, understand, and eventually control the quantum mechanical properties of the particles the behaviour of matter and light creating a toolkit for the technological development of electronics and photonics.

Today, heterostructures are everywhere; they enable technologies such as transistors in computers, solar cells, LED lighting, and lasers. Even the internet would not be possible without use of heterostructures.

Until now, our use of heterostructures has been limited to taking advantage of isolated, individual particles, where their interactions are negligible.

However, if scientists could understand and take control of the interactions between particles within heterostructures, unimagined new technologies will become possible.

Like dancers in a ballet, interacting particles can coordinate their movements in surprising ways. Strongly interacting electrons can: dance together in their place to generate strong magnets; completely stop their journey through a crystal as if frozen to create insulators; or pair up to zoom through a crystal without any resistance to create a superconductor.

Unfortunately, the precise steps in the choreography of interacting particles are tricky to control, and in many cases not even well understood, which prevents their implementation in technologies.

However, an unexpected recent discovery has renewed optimism that this difficult problem can now be tackled.

If two sheets of carbon atoms, called graphene, are placed on top of each other with a relative twist of precisely 1.1 degrees the so-called magic angle an abundance of correlated electron states miraculously appear.

Graphene, the wonder material found in graphite pencil lead, is completely non-magnetic and does not host strongly correlated states. However, when two layers are stacked at the magic angle, it can be switched from insulating to magnetic to superconducting with the use of a tiny battery.

The discovery of these astonishing features is now driving a revolution in our ability to produce, study, and take advantage of heterostructures.

Through these ventures into strongly correlated quantum materials, a whole new generation of low-energy technologies and tools, beyond anything we can currently imagine, becomes ever more likely.

Brian Gerardot is professor at the Institute of Photonics and Quantum Science at Heriot-Watt University, a current chair in emerging technologies at the Royal Academy of Engineering, and a fellow of the Royal Society of Edinburgh. This article expresses his own views. The RSE is Scotland's national academy, bringing great minds together to contribute to the social, cultural and economic well-being of Scotland. Find out more at rse.org.uk and @RoyalSocEd.

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Quantum physics is on the cusp of an astonishing revolution in low-energy technology Professor Brian Gerardot - The Scotsman

Protons are particles that exist in the nucleus of all atoms, with their number defining the elements themselves. Protons, however, are not fundamental particles. Rather, they are composite particles made up of smaller subatomic particles, namely two up quarks and one down quark bound together by force-carrying particles (bosons) called gluons.

This structure isnt certain, however, and quantum physics suggests that along with these three quarks, other particles should be popping into and out of existence at all times, affecting the mass of the proton. This includes other quarks and even quark-antiquark pairs.

Indeed, the deeper scientists have probed the structure of the proton with high-energy particle collisions, the more complicated the situation has become. As a result, for around four decades, physicists have speculated that protons may host a heavier form of quark than up and down quarks called intrinsic charm quarks, but confirmation of this has been elusive.

Now, by exploiting a high-precision determination of the quark-gluon content of the proton and by examining 35 years worth of data, particle physics data researchers have discovered evidence that the proton does contain intrinsic charm quarks.

What makes this result more extraordinary is that this flavor of quark is one-and-a-half times more massive than the proton itself. Yet when it is a component of the proton, the charm quark still only accounts for around half of the composite particles mass.

This counter-intuitive setup is a consequence of the weirdness of quantum mechanics, the physics that governs the subatomic world. This requires thinking of the structure of a particle and what can be found within it as probabilistic in nature.

There are six kinds of quarks in nature, three are lighter than the proton [up, down, and strange quarks] and three are heavier [charm, up, and down quarks], Stefano Forte, NNPDF Collaboration team leader and professor of theoretical Physics at Milan University, tells the Nature Briefing podcast. One would think that only the lighter quarks are inside the proton, but actually, the laws of quantum physics allow also for the heavier quarks to be inside the proton.

Fortethe lead author of a paper published earlier this month in the journal Nature, describing the researchand his team set out to discover if the lightest of these heavier quarks, the charm quark, is present in the proton.

When the Large Hadron Collider (LHC) and other particle accelerators smash protons against each other (and other particles, like electrons) at high energies, what emerges is a shower of particles. This can be used to reconstruct the composition of the original particle and the particles that comprised it, collectively known as partons.

Each of these partons carries away a portion of the overall momentum of the systemthe momentum distributionwith this share of momentum known as the momentum fraction.

Forte and colleagues fed 35 years of data from particle accelerators, including the worlds largest and most powerful machine of this kind, the LHC, to a computer algorithm that pieces proton structure back together by looking for a best fit for its structure at high-energies. From here, the team calculated the structure for the proton when it is at rest.

This resulted in the first evidence that protons do indeed sometimes have charm quarks. These are labeled intrinsic because they are part of the proton for a long time and are still present when the proton is at rest, meaning it doesnt emerge from the high-energy interaction with another particle.

You have a chance, which is small but not negligible, of finding a charm quark in the proton, and when you do find one, it so happens that that charm quark is typically carrying about half of the proton mass, Forte says on the podcast. This is quantum physics, so everything is probabilistic.

Romona Vogt is a high-energy physicist at Lawrence Livermore National Laboratory (LLNL) in California, who wrote a News and Views piece for Nature to accompany the new research paper.

She explains to Popular Mechanics how charm quarks could be connected to proton structure and how the intrinsic charm quark scenario differs from the standard scenario that sees protons comprised of just two up and one down quarks joined by gluons.

Charm quarks come in quark-antiquark pairs in both the standard scenario and the intrinsic charm one, Vogt says. In the standard scenario, a gluon radiates this pairing during a high-energy interaction. Because of the charm quarks mass, it is too heavy to be part of the sea of light up, down, and strange quarks.

This means the charm quark doesnt have a large role when physicists calculate the standard parton momentum distribution functions until momentum reaches a threshold above mass.

Thats very different from the intrinsic charm scenario where the charm distribution carries a large fraction of the proton momentum, Vogt adds. Because in the intrinsic charm quark scenario, the quark-antiquark pair is attached to more than one of the up and down quarks in the proton they travel with. Thats why the charm quarks appear at large momentum fractions.

The proton is more or less empty in this scenario or has a small size configuration because the proton is just up, up, down quarks and charm quark pairs with no other quarks at low momentum fractions in the minimal model of intrinsic charm.

Vogt suggests that the NNPDF Collaborations results could lead other researchers to ask if other quarks could play a role in the composition of protons.

One question these findings might raise is whether or not there are other intrinsic quark scenarios, like intrinsic bottom and intrinsic strangeness, she says.

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Protons Contain a Particle That's Heavier Than the Proton Itself - Popular Mechanics

BLOOMINGTON, Ind. -- Quantum science and engineering can save energy, speed up computation, enhance national security and defense, and innovate health care. With a grant from the National Science Foundation, researchers from Indiana University (both Bloomington and IUPUI campuses), Purdue University and the University of Notre Dame will develop industry- and government-relevant quantum technologies as part of the Center for Quantum Technologies. Purdue will serve as the lead site.

"The Center for Quantum Technologies is based on the collaboration between world experts whose collective mission is to deliver frontier research addressing the quantum technological challenges facing industry and government agencies," said Gerardo Ortiz, Indiana University site director, scientific director of the IU Quantum Science and Engineering Center and professor of physics. "It represents a unique opportunity for the state of Indiana to become a national and international leader in technologies that can shape our future."

"This newly formed center is unique in many aspects," said Ricardo Decca, professor and chair of the Department of Physics at IUPUI. "It brings together experts in many scientific disciplines -- computer science, physics, chemistry, materials science -- from three universities and four campuses and companies developing the next generation of quantum-based information and sensing systems. The future seems very bright."

Given the wide applicability of quantum technologies, the new Center for Quantum Technologies will team with member organizations from a variety of industries, including computing, defense, chemical, pharmaceutical, manufacturing and materials. The center's researchers will develop foundational knowledge into industry-friendly quantum devices, systems and algorithms with enhanced functionality and performance.

"Over the coming decades, quantum science will revolutionize technologies ranging from the design of drugs, materials and energy harvesting systems, to computing, data security, and supply chain logistics," IU Vice President for Research Fred Cate said. "Through the CQT, Indiana will be at the forefront of transferring new quantum algorithms and technologies to industry. We are also looking forward to educating the quantum workforce for the future through the corporate partnerships that are integral to the funding model of the CQT."

Committed industry and government partners include Accenture, the Air Force Research Laboratory, BASF, Cummins, D-Wave, Eli Lilly, Entanglement Inc., General Atomics, Hewlett Packard Enterprise, IBM Quantum, Intel, Northrup Grumman, NSWC Crane, Quantum Computing Inc., Qrypt and Skywater Technology.

Additionally, the Center for Quantum Technologies will train future quantum scientists and engineers to fill the need for a robust quantum workforce. Students engaged with the center will take on many of the responsibilities of principal investigators, including drafting proposals, presenting research updates to members, and planning meetings and workshops.

The center is funded for an initial five years through the NSF's Industry-University Cooperative Research Centers program, which generates breakthrough research by enabling close and sustained engagement between industry innovators, world-class academic teams and government agencies. The IUCRC program is unique in that members fund and guide the direction of research through active involvement and mentoring.

Other academic collaborators include Sabre Kais, center director and distinguished professor of chemical physics at Purdue; Peter Kogge, the University of Notre Dame site director and the Ted H. McCourtney Professor of Computer Science and Engineering; and David Stewart, Center for Quantum Technologies industry liaison officer and managing director of the Purdue Quantum Science and Engineering Institute.

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3 research universities to collaborate with industry, government to develop quantum technologies: News at IU: Indiana University - IU Newsroom

To an outsider, physics and mathematics might appear to be almost identical disciplines. Particularly at the frontiers of theoretical physics, where a very deep knowledge of extraordinarily advanced mathematics is required to grasp even cutting-edge physics from a century ago curved four-dimensional spacetimes and probabilistic wavefunctions among them its clear that predictive mathematical models are at the core of science. Since physics is at the fundamental core of the entire scientific endeavor, its very clear that theres a close relationship between mathematics and all of science.

Yes, mathematics has been incredibly successful at describing the Universe that we inhabit. And yes, many mathematical advances have led to the exploration of new physical possibilities that have relied on those very advances to provide a mathematical foundation. But theres an extraordinary difference between physics and mathematics that one of the simplest questions we can ask will illustrate:

I bet you think you know the answer, and in all honesty, you probably do: its 2, right?

I cant blame you for that answer, and its not exactly wrong. But theres much more to the story, as youre about to find out.

A ball in mid-bounce has its past and future trajectories determined by the laws of physics, but time will only flow into the future for us. While Newtons laws of motion are the same whether you run the clock forward or backward in time, not all of the rules of physics behave identically if you run the clock forward or backward, indicating a violation of time-reversal (T) symmetry where it occurs.

Take a look at the above time-lapse image of a bouncing ball. One look at this tells you a simple, straightforward story.

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This is, quite reasonably, the story youd tell yourself of whats going on.

But why, may I ask, would you tell yourself that story rather than the opposite: that the ball begins on the right side, moving leftward, and that it gains energy, height, and speed after each successive bounce on the floor?

In Newtonian (or Einsteinian) mechanics, a system will evolve over time according to completely deterministic equations, which should mean that if you can know the initial conditions (like positions and momenta) for everything in your system, you should be able to evolve it, with no errors, arbitrarily forward in time. In practice, due to the inability to know the initial conditions to truly arbitrary precisions, this is not true.

The only answer youd likely be able to give, and you may find it dissatisfying even as you give it, is your experience with the actual world. Basketballs, when they bounce, lose a percentage of their initial (kinetic) energy upon striking the floor; youd have to have a specially prepared system designed to kick the ball to higher (kinetic) energies to successfully engineer the alternate possibility. Its your knowledge of physical reality, and your assumption that what youre observing is aligned with your experiences, that lead you to that conclusion.

Similarly, look at the diagram, above, that shows three stars all orbiting around a central mass: a supermassive black hole. If this were a movie, instead of a diagram, you could imagine that all three stars are moving clockwise, that two move clockwise while one moves counterclockwise, that one moves clockwise and two move counterclockwise, or that all three move counterclockwise.

But now, ask yourself this: how would you know whether the movie were running forward in time or backward in time? In the case of gravity just as in the case of electromagnetism or the strong nuclear force youd have no way of knowing. For these forces, the laws of physics are time symmetric: the same forward in time as they are backward in time.

Individual protons and neutrons may be colorless entities, but the quarks within them are colored. Gluons can not only be exchanged between the individual gluons within a proton or neutron, but in combinations between protons and neutrons, leading to nuclear binding. However, every single exchange must obey the full suite of quantum rules, and these strong force interaction are time-reversal symmetric: you cannot tell whether the animated movie here is shown moving forward or backward in time.

Time is an interesting consideration in physics, because while the mathematics offers a set of possible solutions for how a system will evolve, the physical constraint that we have time possesses an arrow, and always progresses forward, never backward ensures that only one solution describes our physical reality: the solution that evolves the system forward in time. Similarly, if we ask the opposite question of What was the system doing in the lead-up until the present moment? the same constraint, that time only moves forward, enables us to choose the mathematical solution that describes how the system was behaving at some prior time.

Consider what this means, then: even given the laws that describe a system, and the conditions that the system possesses at any particular moment, the mathematics is capable of offering multiple different solutions to any problem that we can pose. If we look at a runner, and ask, When will the runners left foot strike the ground? were going to find multiple mathematical solutions, corresponding to the many times their left foot struck the ground in the past, as well as many times their left foot will strike the ground in the future. Mathematics gives you the set of possible solutions, but it doesnt tell you which one is the right one.

Having your camera anticipate the motion of objects through time is just one practical application of the idea of time-as-a-dimension. For any set of conditions that will be recorded throughout time, its plausible to predict when a certain set of conditions will arise, and find multiple possible solutions in the past and future.

But physics does. Physics can allow you to find the correct, physically relevant solution, whereas mathematics can only give you the set of possible outcomes. When you find a ball in mid-flight and know its trajectory perfectly well, you have to turn to the mathematical formulation of the physical laws that govern the system to determine what happens next.

You write down the set of equations that describe the balls motion, you manipulate and solve them, and then you plug in the specific values that describe the conditions of your particular system. When you work the mathematics that describe that system to its logical conclusion, that exercise will give you (at least) two possible solutions as to precisely when-and-where it will hit the ground in the future.

One of those solutions does, indeed, correspond to the solution youre looking for. It will tell you, at a particular point in the future, when the projectile will first strike the ground, and what its positions will be in all three spatial dimensions when that occurs.

But there will be another solution that corresponds to a negative time: a time in the past where the projectile would also have struck the ground. (You can also find the 3D spatial position of where that projectile would be at that time, if you like.) Both solutions have equal mathematical validity, but only one is physically relevant.

This image shows the parabolic trail left by a rocket after launch. If you would simply calculate the trajectory of this object, assuming no further engine firings after launch, youd get multiple solutions for where/when it would land. One solution is correct, corresponding to the future; the other solution is mathematically correct but physically incorrect, corresponding to a time in the past.

Thats not a deficiency in mathematics; thats a feature of physics, and of science in general. Mathematics tells you the set of possible outcomes. But the scientific fact that we live in a physical reality and in that reality, wherever and whenever we make a measurement, we observe only one outcome teaches us that there are additional constraints beyond what mere mathematics provides. Mathematics tells you what outcomes are possible; physics (and science in general) is what you use to pick out which outcome is (or was, or will be) relevant for the specific problem youre trying to address.

In biology, we can know the genetic makeup of two parent organisms, and can predict the probability with which their offspring will inherent a certain combination of genes. But if these two organisms combine their genetic material to actually make an offspring organism, only one set of combinations will be realized. Furthermore, the only way to determine which genes actually were inherited by the child of the two parents would be to make the critical observations and measurements: you have to gather the data and determine the outcome. Despite the myriad of mathematical possibilities, only one outcome actually occurs.

An Irish immigrant (center) waiting next to an Italian immigrant and her children at Ellis Island, circa 1920. The womans children each possess 50% of her DNA, but specifically which 50% is present in each childs genetic makeup varies not only from child-to-child, but must be observed and measured, explicitly, to correctly determine which of all the possible outcomes actually occurred.

The more complicated your system, the more difficult it becomes to predict the outcome. For a room filled with large numbers of molecules, asking What fate will befall any one of these molecules? becomes a practically impossible task, as the number of possible outcomes after only a small amount of time passes becomes greater than the number of atoms in the entire Universe.

Some systems are inherently chaotic, where minuscule, practically immeasurable differences in the initial conditions of a system lead to vastly different potential outcomes.

Other systems are inherently indeterminate until theyre measured, which is one of the most counterintuitive aspects of quantum mechanics. Sometimes, the act of performing a measurement to literally determine the quantum state of your system winds up changing the state of the system itself.

In all of these cases, mathematics offers a set of possible outcomes whose probabilities can be determined and calculated in advance, but only by performing the critical measurement can you actually determine which one outcome has actually occurred.

Trajectories of a particle in a box (also called an infinite square well) in classical mechanics (A) and quantum mechanics (B-F). In (A), the particle moves at constant velocity, bouncing back and forth. In (B-F), wavefunction solutions to the Time-Dependent Schrodinger Equation are shown for the same geometry and potential. The horizontal axis is position, the vertical axis is the real part (blue) or imaginary part (red) of the wavefunction. These stationary (B, C, D) and non-stationary (E, F) states only yield probabilities for the particle, rather than definitive answers for where it will be at a particular time.

This takes us all the way back to the initial question: what is the square root of 4?

Chances are, you read that question, and the number 2 immediately popped into your head. But thats not the only possible answer; it could have been -2 just as easily. After all, (-2) equals 4 just as surely as (2) equals 4; theyre both admissible solutions.

If I had gone further and asked, What is the fourth root (the square root of the square root) of 16? you could have then gone and given me four possible solutions. Each of these following numbers,

when raised to the fourth power, will yield the number 16 as the mathematical answer.

This graph shows the function y = x. Note that there are two possible solutions on the y-axis for every value of x. Two of those solutions correspond to x = 4: y = 2 and y = -2. Both solutions are, mathematically, equally valid. But theres only one physical Universe that we inhabit, and each physical problem must be considered individually to determine which of these solutions is physically relevant.

But in the context of a physical problem, there will only be one of these many possible solutions that actually reflects the reality we inhabit. The only way to determine which one is correct is either to go out and measure reality and pick out the physically relevant solution, or to know enough about your system and apply the relevant physical conditions so that youre not simply calculating the mathematical possibilities, but that youre capable of choosing the physically relevant solution and rejecting the non-physical ones.

Sometimes, that means we have multiple admissible solutions at once that are all plausible for explaining an observed phenomenon. It will only be through the obtaining of more, superior data that rules out certain possibilities while remaining consistent with others that enables us to determine which of the possible solutions actually remain viable. This approach, inherent to the process of doing science, helps us make successively better and better approximations to our inhabited reality, allowing us to tease out what is true about our Universe amidst the possibilities of what could have been true in the absence of that critical data.

NASAs Curiosity Mars Rover detected fluctuations in the methane concentration of Marss atmosphere seasonally and at specific locations on the surface. This can be explained via either geochemical or biological processes; the evidence is not sufficient to decide at present. However, future missions, such as Mars Sample Return, may enable us to determine whether fossilized, dormant, or active life exists on Mars. Right now, we can only narrow down the physical possibilities; more information is required to determine which pathway accurately reflects our physical reality.

The biggest difference between physics and mathematics is simply that mathematics is a framework that, when applied wisely, can accurately describe certain properties about a physical system in a self-consistent fashion. However, mathematics is limited in what it can achieve: it can only give you a set of possible outcomes sometimes weighted by probability and sometimes not weighted at all for what could occur or could have occurred in reality.

Physics is much more than mathematics, however, as no matter when we look at the Universe or how we look at it, there will be only one observed outcome that has actually occurred. Mathematics shows us the full set of all possible outcomes, but its the application of physical constraints that allows us to actually determine what is true, real, or what actual outcomes have occurred in our reality.

If you can remember that the square root of 4 isnt always 2, but is sometimes -2 instead, you can remember the difference between physics and mathematics. The latter can tell you all the possible outcomes that could occur, but what elevates something to the realm of science, rather than pure mathematics, is its connection to our physical reality. The answer to the square root of 4 will always be either 2 or -2, and the other solution will be rejected by a means that mathematics alone can never fully determine: on physical grounds, alone.

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The big difference between physics and mathematics - Big Think

The grant will enhance research capabilities at UAB by facilitating acquisition of a Physical Properties Measurement System.

Wenli Bi, Ph.DThe National Science Foundation has awarded a Major Research Instrumentation grant of $419,614 to Wenli Bi, Ph.D., assistant professor in the University of Alabama at Birmingham theCollege of Arts and SciencesDepartment of Physics.

The grant, led by Bi, is titled MRI: Acquisition of a Quantum Design Physical Properties Measurement System for Materials Research and Education.

The MRI grant supports the acquisition of a Physical Properties Measurement System from Quantum Design, which is a state-of-the-art, highly automated and multifunctional system capable of measuring a multitude of material properties at cryogenic temperature, high magnetic field and high pressure.

The PPMS will greatly expand the materials research capability at UAB Physics by directly benefiting seven research groups in our department, Bi said. It will enable integration of all three extreme sample environments: high pressure up to 1 million atmosphere, low temperature down to 1.9 K and high magnetic field up to 9 Tesla for materials research.

Bi believes the grant will open new avenues for intra- and interdepartmental collaborations with the acquisition of PPMS. Additionally, she hopes it will foster education of diverse graduate and undergraduate students, and train high school students and STEM teachers through research, education and outreach activities. It will also help develop new hands-on modules for lab courses at UAB to demonstrate basic physics principles.

Learn more about physics degrees at UAB here.

The grant will develop and use exhibits on advanced characterization of materials properties and applications for outreach at McWane Science Center to promote science literacy in the general public and inspire K-12 students to pursue STEM areas.

The addition of this new research capability will foster new collaborations with other diverse physics and materials research groups in Central Alabama, Bi said.

UAB faculty Yogesh Vohra, Ph.D., professor university scholar and associate dean in the Department of Physics; Mary Ellen Zvanut, Ph.D., professor and graduate program director; Sergey Mirov, Ph.D., university professor; and Renato Camata, Ph.D., associate professor and undergraduate program director; are the co-principal investigators of this project.

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NSF grant brings state-of-the-art materials research equipment to the UAB Department of Physics - University of Alabama at Birmingham

Its not hyperbole to suggest that there are two worlds one before and one after the detonation of the atomic bomb.

Interestingly, there are two Southern Indiana connections to J. Robert Oppenheimer, leader of the Manhattan Project.

Joseph Fabian Mattingly, the uncle of Evansville baseball legend Don, was present July 6, 1945 as the gadget was successfully tested in Alamogordo, New Mexico. The U.S. dropped the A-bomb on Hiroshima on Aug. 6 and Nagasaki on Aug. 9 and Japan surrendered from World War II shortly thereafter.

It was very bright, Joseph Fabian Mattingly told the Evansville Courier in 1995. When it lit up the sky, the colors were beautiful violet and purple. It was a pretty sight. We were on a mountainside about 17 miles out.

It was bright as hell, and it was quiet. Eerie. There was no sound for a minute and a half. Then, whoom! A thunderous reverberation from the mountains occurred again and again. The light was like looking at the sun. There was a cloud layer about 17,000 feet and it looked like there was somebody at the end of the clouds shaking them like a bedsheet, vibrating up and down.

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Then 86, that was Mattinglys recollection of seeing the detonation in the New Mexico desert. Randy Mattingly said his uncle, who died at 91 in 2000, made for quite a conversation piece at family gatherings when he was growing up.

Initially, I was young enough that it didnt register to me, Randy told the Courier & Press. The A-bomb didnt really register to me. He showed us the goggles (he wore during the detonation) at our grandfathers house.

Although those goggles (welders glasses) might bring in quite a price at an auction, Randy isnt sure where they are.

Melba Newell Phillips, a female trailblazer from Hazleton in Gibson County, Indiana, worked with J. Robert Oppenheimer years before the A-bomb exploded.

Phillips, who died in 2004 at age 97, studied under and collaborated with Oppenheimer. She was part of a heroic age of physics, a time when scientists were just beginning to study quantum theory and other areas of physics that would bring the world into the atomic age, according to American Prometheus: the Triumph and Tragedy of J. Robert Oppenheimer a Pulitzer Prize-winning biography by Kai Bird and Martin J. Sherwin. It is the basis for an upcoming biographical film, Oppenheimer, scheduled to be released in July 2023.

Barely 16, Phillips graduated from Union High School in rural Pike County in 1923. She began her undergraduate work at Oakland City University and worked with Oppenheimer at the University of California at Berkeley in the early 1930s. During the Red Scare of 1952, she stood up to congressional bullies of Senator Joseph McCarthy, but lost her job at Brooklyn College in the process, said Oakland City University social sciences professor and area historian Randy Mills.

Still, she persevered. In fact, the American Association of Physics Teachers in 1983 recognized her commitment to education by creating the Melba Newell Phillips Award, a national honor given yearly to the individual who is judged to have made an exceptional contribution to physics education.

In 1943, while working at the U.S. Weather Bureau in Evansville, Joseph Mattingly received a call from Dr. Philemon Edwards Church, who was assigned to the Manhattan Project to study/predict weather patterns and turbulence for the project, according to the July 2006 Mattingly Family Newsletter.

Church invited Mattingly, a 1927 Memorial High School graduate, to take part in his studies at the University of Chicago. He was given special leave where his position with the Weather Bureau was protected for the duration of the war. Mattingly also received, over objection from local military authorities, a special military deferment personally from Gen. Leslie Groves, Military Chief of the Manhattan Project.

After training in Chicago, he was sent to Hanford, Washington, assigned to Hanford Engineering Works, a division of E.I. DuPont. DuPont had erected the first full-size nuclear reactor at this site and would produce plutonium for the atomic bomb. Few of the 20,000 workers at Hanford, including Mattingly, knew what was going on or what the Hanford site mission entailed. One mile from the reactor, they built a tower several hundred feet tall that his team used to make continuous observations of barometric pressure, temperature, humidity, and cloud cover in an attempt to track the radioactive smoke from the production facility. Geiger counters were placed all over the area.

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Every morning Mattingly boarded a Piper Cub and was taken up to 2,000 feet to track smoke from the stacks. The Hanford Site was 600 square miles and the smoke was to diffuse before it got off the reservation. No one knew what was really going on other than a war project that involved something called the gadget.

The Hanford area ws later considered one of the most contaminated places in the world. Mattingly said at least one person died of cancer and it was in Hanford that his wife, Adeline, became ill with Parkinson's disease.

"But there's no way to know if radiation had anything to do with it," Mattingly told the Evansville Courier.

In July of 1945, Mattingly was sent to Alamogordo. Uncle Fabian was on hand to witness the most powerful development of the century. Following are a few of the quotes from his notebook made on the date of the detonation: White hot 1 mile. The second drawing shows a mushroom with the note, Golden glowing one-half mile. The third drawing shows a larger cloud and the note, Violet brilliant color. Other notes from his address book: Base precaution C, burn from ultraviolet rays, (2) prone on face, (3) eye protection, (4) evacuation, in case of disaster. One half hour after blast, stratified layers aloft, no longer distinguishable from Albuquerque road. B-29 at 24,000 feet reported light bump at altitude above shot.

When Mattingly returned to Hanford, he was the only one of the 20,000 workers who knew what the gadget was and what it could do. He didnt know how it was going to be used until Aug. 6, 1945, when the story broke that the bomb Little Boy was dropped over the city of Hiroshima and three days later the bomb Fat Man was dropped over the city of Nagasaki.

Unlike the Trinity Site in New Mexico, the Hanford reactor site is one of the most polluted sites in the world. In their rush they just didnt know what the consequences were to the environment. The government is spending $1 billion per year on cleanup that will go for several more years.

In 1947, Mattingly returned to the University of Washington in a sub-faculty position in the newly formed Department of Meteorology and Climatology. He returned to the U.S. Weather Bureau in Evansville in 1949. He built his house in the summer of 1950 on St. George Road and lived there the rest of his life next door to his sister Catherine Hess.

After the U.S. dropped atomic bombs on Japan, Phillips joined other scientists organized to prevent future nuclear wars.She took a great hit to her career during the Cold War for standing up to McCarthyism. Colleagues and students notedher intellectual honesty, self-criticism, and style, and called her a role model for principle and perseverance" in "Melba Phillips: Leader in Science and Conscience."

As she moved up the academic ranks, Phillips pursued graduate research under Oppenheimer and earned her doctorate in 1933. Within a few years she was known throughout the physics world because of her contribution to the field via theOppenheimer-Phillips effect, according to "Women in Physics."

The 1935 Oppenheimer-Phillips Effect explained what was at the time unexpected behavior of accelerated deuterons (nuclei of deuterium, or heavy hydrogen atoms) in reactions with other nuclei, according to aUniversity of Chicagopress release. When Oppenheimer died in 1967, hisNew York Timesobituary noted his and Phillips discovery as a basic contribution to quantum theory.

Phillips was subsequently fired from her university positions due to a law which required the termination of any New York City employee who invoked the Fifth Amendment.

Bonner explained, McCarran was a specialist at putting people in the position in which they had to invoke the Fifth Amendment. It was a deliberate expression of the McCarthyism of the time.

In a1977 interview,Phillips briefly discussed the incident (although she was reluctant because she was trying to keep the interviewer focused on her scientific accomplishments).She stated: I was fired from Brooklyn College for failure to cooperate with the McCarran Committee, and I think that ought to go into the record . . . city colleges were particularly vulnerable, and the administration was particularly McCarthyite.

Phillips stated that she wasnt particularly political. Her objection to cooperating had been a matter of principle.

In 1987, Brooklyn College publicly apologized for firing Phillips, and in 1997 created the aforementioned scholarship in her name. Phillips died on Nov. 8, 2004 in Petersburg, Indiana.

TheNew York Timesreferred to Phillips in her obituary as a pioneer in science education and noted that at a time when there were few women working as scientists, Dr. Phillips was leader among her peers.

Her accomplishments helped pave the way for other women in the sciences.

In a 1977 interview, Phillips addressed the problems women face in aspiring to science careers an a 1977 interview, stating: "Were not going to solve them, but, as Ive been saying all the time; if we make enough effort, well make progress; and I think progress has been made. We sometimes slip back, but we never quite slip all the way back; or we never slip back to the same place. Theres a great deal of truth in saying that progress is not steady no matter how inevitable."

Contact Gordon Engelhardt by email at gordon.engelhardt@courierpress.com or on Twitter @EngGordon.

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Evansville's ties to the first detonation of the A-bomb in 1945 - Courier & Press

Fri, 08/26/2022 - 10:53am | By: Josh Stricklin

The University of Southern Mississippi (USM) continues to expand its online catalog with the addition of the Physics Master of Science degree. The addition of this program means USM offers a practical and accessible opportunity for students to continue their education in physics.

This program offers a unique opportunity to explore a variety of research topics. Dr. Michael Vera, Associate Professor of Physics and Astronomy, says The Physics Masters program consists of courses in Classical Mechanics, Quantum Mechanics, Statistical Physics and Electromagnetism as well as research opportunities in a variety of fields including computation, materials science, nuclear theory, optics and wave propagation.

These four core classes give students a shared knowledge in physics while allowing them to pursue their own interests within the field. And USMs online delivery gives students a unique chance to conduct their work at a distance while having regular access to the professors.

With its synchronous format, says Dr. Vera, the online option for the Physics Masters degree provides both the accessibility of remote delivery and the personal interaction of a traditional classroom. Students are able to ask questions, and benefit from the questions of other students, during live class sessions.

With a full spectrum of classes and strong computational focus, the Masters in Physics program at USM sets students up for a wide range of potential careers. While education and research labs are clear employers, graduates of the Physics program can find themselves in myriad fields ranging from modeling and software development to engineering or even financial modeling.

The online Physics Masters degree is an incredible opportunity for students, says Dr. Tom Hutchinson, Dean of Online Learning and Enrollment for the Office of Online Learning. Students can continue their education where they live, while taking advantage of USMs amazing faculty in real time. And because USM offers a wide range of research possibilities, students can do what they love in a field in which they have a genuine interest.

The online Physics MS is designed to help students achieve everything they can in their careers. This program admits students during the fall, spring, and summer semesters, and with USM's online delivery, students can finish school with a world of potential at their fingertips. Students looking to grow their knowledge in physics should visit the online Physics MS page.

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USM School of Mathematics and Natural Science adds a Physics Masters Degree to Online Learners - The University of Southern Mississippi

Compounding the danger is the lack of anyAI regulation. Instead, unaccountable technology conglomerates, such as Google and Meta, have assumed the roles of judge and jury in all things AI. They are silencing dissenting voices, including their own engineers who warn of the dangers.

The worlds failure to rein in the demon of AIor rather, the crude technologies masquerading as suchshould serve to be a profound warning. There is an even more powerful emerging technology with the potential to wreak havoc, especially if it is combined with AI:quantum computing. We urgently need to understand this technologys potential impact, regulate it, and prevent it from getting into the wrong hands before it is too late. The world must not repeat the mistakes it made by refusing to regulate AI.

Although still in its infancy, quantum computing operates on a very different basis from todays semiconductor-based computers. If thevarious projectsbeing pursued around the world succeed, these machines will be immensely powerful, performing tasks in seconds that would takeconventional computersmillions of years to conduct.

Because of the technologys immense power and revolutionary applications, quantum computing projects are likely part of defense and other government research already.

Semiconductors represent information as a series of 1s and 0sthats why we call it digital technology. Quantum computers, on the other hand, use a unit of computing called aqubit. A qubit can hold values of 1 and 0 simultaneously by incorporating a counterintuitive property in quantum physics called superposition. (If you find this confusing, youre in good companyit can be hard to grasp even for experienced engineers.) Thus, two qubits could represent the sequences 1-0, 1-1, 0-1, and 0-0, all in parallel and all at the same instant. That allows a vast increase in computing power, which grows exponentially with each additional qubit.

Quantum computing researchers at Duke observe tipping point

If quantum physics leaves the experimental stage and makes it into everyday applications, it will find many uses and change many aspects of life. With their power to quickly crunch immense amounts of data that would overwhelm any of todays systems,quantum computerscould potentially enable better weather forecasting, financial analysis, logistics planning, space research, and drug discovery. Some actors will very likely use them for nefarious purposes, compromising bank records, private communications, and passwords on every digital computer in the world. Todays cryptography encodes data in large combinations of numbers that are impossible to crack within a reasonable time using classic digital technology. But quantum computerstaking advantage of quantum mechanical phenomena, such as superposition, entanglement, and uncertaintymay potentially be able to try out combinations so rapidly that they could crack encryptions by brute force almost instantaneously.

To be clear, quantum computing is still in an embryonic stagethough where, exactly, we can only guess. Because of the technologys immense potential power and revolutionary applications, quantum computing projects are likely part of defense and other government research already. This kind of research isshrouded in secrecy, and there are a lot of claims and speculation about milestones being reached. China, France, Russia, Germany, the Netherlands, Britain, Canada, and India are known to be pursuing projects. In the United States, contenders include IBM, Google, Intel, and Microsoft as well as various start-ups, defense contractors, and universities.

Despite the lack of publicity, there have been credible demonstrations of some basic applications, includingquantum sensorsable to detect and measure electromagnetic signals. One such sensor was used to precisely measureEarths magnetic fieldfrom the International Space Station.

IBM unveils roadmap for developing quantum-powered supercomputers

In another experiment, Dutch researchers teleported quantum information across a rudimentaryquantum communication network. Instead of using conventional optical fibers, the scientists used three small quantum processors to instantly transfer quantum bits from a sender to a receiver. These experiments havent shown practical applications yet, but they could lay the groundwork for a future quantum internet, where quantum data can be securely transported across a network of quantum computers faster than the speed of light. So far, thats only been possible in the realm of science fiction.

The Biden administration considers the risk of losing the quantum computing race imminent and dire enough that it issuedtwo presidential directivesin May: one to place theNational Quantum Initiativeadvisory committee directly under the authority of the White House and another to directgovernment agenciesto ensure U.S. leadership in quantum computing while mitigating the potential security risks quantum computing poses to cryptographic systems.

Experiments are also working tocombinequantum computing with AI to transcend traditional computers limits. Today, large machine-learning models take months to train on digital computers because of the vast number of calculations that must be performedOpenAIs GPT-3, for example, has 175 billion parameters. When these models grow into the trillions of parametersa requirement for todays dumb AI to become smartthey will take even longer to train. Quantum computers could greatly accelerate this process while also using less energy and space. In March 2020, Google launchedTensorFlowQuantum, one of the first quantum-AI hybrid platforms that takes the search for patterns and anomalies in huge amounts of data to the next level.Combined with quantum computing, AI could, in theory, lead to even more revolutionary outcomes than the AI sentience that critics have been warning about.

Quantum breakthrough? Duke, IonQ invent means to accelerate key quantum techniques

Given the potential scope and capabilities ofquantum technology, it is absolutely crucial not to repeat the mistakes made with AIwhere regulatory failure has given the world algorithmic bias that hypercharges human prejudices, social media that favors conspiracy theories, and attacks on the institutions of democracy fueled by AI-generated fake news and social media posts. The dangers lie in the machines ability to make decisions autonomously, with flaws in the computer code resulting in unanticipated, often detrimental, outcomes. In 2021, the quantum community issued acall for actionto urgently address these concerns. In addition, critical public and private intellectual property on quantum-enabling technologies must be protected fromtheft and abuseby the United States adversaries.

There are national defense issues involved as well. In security technology circles, the holy grail is whats called acryptanalytically relevant quantum computera system capable of breaking much of the public-key cryptography that digital systems around the world use, which would enable blockchain cracking, for example. Thats a very dangerous capability to have in the hands of an adversarial regime.

Experts warn thatChinaappears to have a lead in various areas of quantum technology, such as quantum networks and quantum processors. Two of the worlds most powerful quantum computers were beenbuilt in China, and as far back as 2017, scientists at the University of Science and Technology of China in Hefei built the worlds firstquantum communication networkusing advanced satellites. To be sure, these publicly disclosed projects are scientific machines to prove the concept, with relatively little bearing on the future viability of quantum computing. However, knowing that all governments are pursuing the technology simply to prevent an adversary from being first, these Chinese successes could well indicate an advantage over the United States and the rest of the West.

Beyond accelerating research, targeted controls on developers, users, and exports should therefore be implemented without delay. Patents, trade secrets, and relatedintellectual property rightsshould be tightly secureda return to the kind of technology control that was a major element of security policy during the Cold War. The revolutionary potential of quantum computing raises the risks associated withintellectual property theftby China and other countries to a new level.

Exec shares six predictions for quantum computing industry in 2022

Finally, to avoid theethical problemsthat went so horribly wrong with AI and machine learning, democratic nations need to institute controls that both correspond to the power of the technology as well as respect democratic values, human rights, and fundamental freedoms. Governments must urgently begin to think about regulations,standards, and responsible usesand learn from the way countries handled or mishandled other revolutionary technologies, including AI, nanotechnology, biotechnology, semiconductors, and nuclear fission. The United States and otherdemocratic nationsmust not make the same mistake they made with AIand prepare for tomorrows quantum era today.

About the authors

Vivek Wadhwais a columnist atForeign Policy, an entrepreneur, and the co-author ofFrom Incremental to Exponential: How Large Companies Can See the Future and Rethink Innovation.Twitter:@wadhwa

Mauritz Kopis a fellow and visiting scholar at Stanford University.Twitter:@MauritzKop

Duke Quantum Center officially opens, offering a look at computings future

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Quantum computing is an even bigger threat than artificial intelligence - here's why - WRAL TechWire

For over a century, astronomers have known that the Universe has been expanding since the Big Bang. For the first 8 billion years, the expansion rate was relatively consistent since it was held back by the force of gravitation.

However, thanks to missions like the Hubble Space Telescope, astronomers have since learned that roughly 5 billion years ago, the rate of expansion has been accelerating.

This led to the widely-accepted theory that a mysterious force is behind the expansion (known as Dark Energy), while some insist that the force of gravity may have changed over time.

This is a contentious hypothesis since it means that Einstein's General Theory of Relativity (which has been validated nine ways from Sunday) is wrong.

But according to a new study by the international Dark Energy Survey (DES) Collaboration, the nature of gravity has remained the same throughout the entire history of the Universe.

These findings come shortly before two next-generation space telescopes (Nancy Grace Roman and Euclid) are sent to space to conduct even more precise measurements of gravity and its role in cosmic evolution.

The DES Collaboration comprises researchers from universities and institutes in the US, UK, Canada, Chile, Spain, Brazil, Germany, Japan, Italy, Australia, Norway, and Switzerland.

Their third-year findings were presented at the International Conference on Particle Physics and Cosmology (COSMO'22), which took place in Rio de Janeiro from August 22nd to 26th.

They were also shared in a paper titled "Dark Energy Survey Year 3 Results: Constraints on extensions to Lambda CDM with weak lensing and galaxy clustering" that appeared in the American Physical Society journal Physical Review D.

Einstein's General Theory of Relativity, which he finalized in 1915, describes how the curvature of spacetime is altered in the presence of gravity.

For over a century, this theory has accurately predicted almost everything in our Universe, from Mercury's orbit and gravitational lensing to the existence of black holes.

But between the 1960s and 1990s, two discrepancies were discovered that led astronomers to wonder if Einstein's theory was correct. First, astronomers noted that the gravitational effects of massive structures (like galaxies and galaxy clusters) did not accord with their observed mass.

This gave rise to the theory that space is filled with an invisible mass that interacts with 'normal' (aka. 'luminous' or visible) matter via gravity. Meanwhile, the observed expansion of the cosmos (and how it is subject to acceleration) gave rise to the theory of Dark Energy and the Lambda Cold Dark Matter (Lambda CDM) cosmological model.

Cold Dark Matter is an interpretation where this mass is composed of large, slow-moving particles while Lambda represents Dark Energy. In theory, these two forces constitute 95 percent of the total mass-energy content of the Universe, yet all attempts to find direct evidence of them have failed.

The only possible alternative is that Relativity needs to be modified to account for these discrepancies. To find out if that's the case, members of the DES used the Victor M. Blanco 4-meter Telescope at the Cerro Telolo Inter-American Observatory in Chile to observe galaxies up to 5 billion light-years away.

They hoped to determine if gravity has varied over the past 5 billion years (since the acceleration began) or over cosmic distances. They also consulted data from other telescopes, including the ESA's Planck satellite, which has been mapping the Cosmic Microwave Background (CMB) since 2009.

They paid close attention to how the images they saw contained subtle distortions due to dark matter (gravitational lenses). As the first image released from the James Webb Space Telescope (JWST) illustrated, scientists can infer the strength of gravity by analyzing the extent to which a gravitational lens distorts spacetime.

So far, the DES Collaboration has measured the shapes of over 100 million galaxies, and the observations all match what General Relativity predicts. The good news is that Einstein's theory still holds, but this also means that the mystery of Dark Energy persists for the time being.

Luckily, astronomers will not have to wait long before new and more detailed data is available. First, there's the ESA's Euclid mission, slated for launch by 2023 at the latest. This mission will map the geometry of the Universe, looking 8 billion years into the past to measure the effects of Dark Matter and Dark Energy.

By May 2027, it will be joined by NASA's Nancy Grace Roman Space Telescope, which will look back over 11 billion years. These will be the most detailed cosmological surveys ever conducted and are expected to provide the most compelling evidence for (or against) the Lambda-CDM model.

As study co-author Agns Fert, who conducted the research as a postdoctoral researcher at JPL, said in a recent NASA press release:

"There is still room to challenge Einstein's theory of gravity, as measurements get more and more precise. But we still have so much to do before we're ready for Euclid and Roman. So it's essential we continue to collaborate with scientists around the world on this problem as we've done with the Dark Energy Survey."

In addition, observations provided by Webb of the earliest stars and galaxies in the Universe will allow astronomers to chart the evolution of the cosmos from its earliest periods. These efforts have the potential to answer some of the most pressing mysteries in the Universe.

These include how Relativity and the observed mass and expansion of the Universe coincide but could also provide insight into how gravity and the other fundamental forces of the Universe (as described by quantum mechanics) interact a Theory of Everything (ToE).

If there's one thing that characterizes the current era of astronomy, it is the way that long-term surveys and next-generation instruments are coming together to test what has been the stuff of theory until now.

The potential breakthroughs that these could lead to are sure to both delight and confound us. But ultimately, they will revolutionize the way we look at the Universe.

This article was originally published by Universe Today. Read the original article.

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Gravity Has Stayed Constant For The Entire Age of The Universe, Study Finds - ScienceAlert

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Credit: Image credit: Bjrn Annby-Andersson

As the size of modern technology shrinks down to the nanoscale, weird quantum effectssuch as quantum tunneling, superposition, and entanglementbecome prominent. This opens the door to a new era of quantum technologies, where quantum effects can be exploited. Many everyday technologies make use of feedback control routinely; an important example is the pacemaker, which must monitor the users heartbeat and apply electrical signals to control it, only when needed. But physicists do not yet have an equivalent understanding of feedback control at the quantum level. Now, FQXi-funded physicists have developed a master equation that will help engineers understand feedback at the quantum scale. Their results are published in the journal Physical Review Letters.

It is vital to investigate how feedback control can be used in quantum technologies in order to develop efficient and fast methods for controlling quantum systems, so that they can be steered in real time and with high precision, says co-author Bjrn Annby-Andersson, a quantum physicist at Lund University, in Sweden.

An example of a crucial feedback-control process in quantum computing is quantum error correction. A quantum computer encodes information on physical qubits, which could be photons of light, or atoms, for instance. But the quantum properties of the qubits are fragile, so it is likely that the encoded information will be lost if the qubits are disturbed by vibrations or fluctuating electromagnetic fields. That means that physicists need to be able to detect and correct such errors, for instance by using feedback control. This error correction can be implemented by measuring the state of the qubits and, if a deviation from what is expected is detected, applying feedback to correct it.

It is vital to investigate how feedback control can be used in quantum technologies in order to develop efficient and fast methods for controlling quantum systems, so that they can be steered in real time and with high precision, says co-author Bjrn Annby-Andersson, a quantum physicist at Lund University, in Sweden.

But feedback control at the quantum level presents unique challenges, precisely because of the fragility physicists are trying to mitigate against. That delicate nature means that even the feedback process itself could destroy the system. It is necessary to only interact weakly with the measured system, preserving the properties we want to exploit, says Annby-Andersson.

It is thus important to develop a full theoretical understanding of quantum feedback control, to establish its fundamental limits. But most existing theoretical models of quantum feedback control require computer simulations, which typically only provide quantitative results for specific systems. It is difficult to draw general, qualitative conclusions, Annby-Andersson says. The few models that can provide qualitative understanding are only applicable on a narrow class of feedback controlled systemsthis type of feedback is typically referred to as linear feedback.

Pen and Paper

Annby-Andersson and his colleagues have now developed a master equation, called a Quantum Fokker-Planck equation, that enables physicists to track the evolution of any quantum system with feedback control over time. The equation can describe scenarios that go beyond linear feedback, says Annby-Andersson. In particular, the equation can be solved with pen and paper, rather than having to rely on computer simulations.

The team tested their equation by applying it to a simple feedback model. This confirmed that the equation provides physically sensible results and also demonstrated how energy can be harvested in microscopic systems, using feedback control. The equation is a promising starting point for future studies of how energy may be manipulated with the help of information on a microscopic level, says Annby-Andersson.

The analysis and related experiments are partially funded by a grant from the Foundational Questions Institute, FQXi. It is a great example of a successful collaboration between two different teams based at the University of Maryland, College Park, and at Lund University, says co-author and FQXi member Peter Samuelsson, a quantum physicist at Lund University.

The equation is a promising starting point for future studies of how energy may be manipulated with the help of information on a microscopic level, says Annby-Andersson.

The team is now investigating a system that makes use of feedback to manipulate energy in quantum dotstiny semiconducting crystals just billionths of a meter across. An important future direction is to use the equation as a tool for inventing novel feedback protocols that can be used for quantum technologies, says Annby-Andersson.

This work was partially supported through FQXi's Information as Fuel program.You can read more about the teams grant in the Foundational Questions Institute, FQXi article: Connect the Quantum Dots for a New Kind of Fuel,by Colin Stuart.

Journal reference: Quantum Fokker-Planck Master Equation for Continuous Feedback Control

ABOUT US

The Foundational Questions Institute, FQXi, catalyzes, supports, and disseminates research on questions at the foundations of science, particularly new frontiers in physics and innovative ideas integral to a deep understanding of reality but unlikely to be supported by conventional funding sources. Visit fqxi.orgfor more information.

Physical Review Letters

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Quantum Fokker-Planck Master Equation for Continuous Feedback Control

25-Jul-2022

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Master equation to boost quantum technologies - EurekAlert