Monthly Archives: February 2021

Study by the University of Bonn determines minimum time for complex quantum operations.

Even in the world of the smallest particles with their own special rules, things cannot proceed infinitely fast. Physicists at the University of Bonn have now shown what the speed limit is for complex quantum operations. The study also involved scientists from MIT, the universities of Hamburg, Cologne and Padua, and the Jlich Research Center. The results are important for the realization of quantum computers, among other things. They are published in the prestigious journal Physical Review X, and covered by the Physics Magazine of the American Physical Society.

Suppose you observe a waiter (the lockdown is already history) who on New Years Eve has to serve an entire tray of champagne glasses just a few minutes before midnight. He rushes from guest to guest at top speed. Thanks to his technique, perfected over many years of work, he nevertheless manages not to spill even a single drop of the precious liquid.

A little trick helps him to do this: While the waiter accelerates his steps, he tilts the tray a bit so that the champagne does not spill out of the glasses. Halfway to the table, he tilts it in the opposite direction and slows down. Only when he has come to a complete stop does he hold it upright again.

Atoms are in some ways similar to champagne. They can be described as waves of matter, which behave not like a billiard ball but more like a liquid. Anyone who wants to transport atoms from one place to another as quickly as possible must therefore be as skillful as the waiter on New Years Eve. And even then, there is a speed limit that this transport cannot exceed, explains Dr. Andrea Alberti, who led this study at the Institute of Applied Physics of the University of Bonn.

In their study, the researchers experimentally investigated exactly where this limit lies. They used a cesium atom as a champagne substitute and two laser beams perfectly superimposed but directed against each other as a tray. This superposition, called interference by physicists, creates a standing wave of light: a sequence of mountains and valleys that initially do not move. We loaded the atom into one of these valleys, and then set the standing wave in motion this displaced the position of the valley itself, says Alberti. Our goal was to get the atom to the target location in the shortest possible time without it spilling out of the valley, so to speak.

First author Manolo Rivera Lam (left) and principal investigator Dr. Andrea Alberti (right) at the Institute of Applied Physics at the University of Bonn. Credit: Volker Lannert/Uni Bonn

The fact that there is a speed limit in the microcosm was already theoretically demonstrated by two Soviet physicists, Leonid Mandelstam and Igor Tamm more than 60 years ago. They showed that the maximum speed of a quantum process depends on the energy uncertainty, i.e., how free the manipulated particle is with respect to its possible energy states: the more energetic freedom it has, the faster it is. In the case of the transport of an atom, for example, the deeper the valley into which the cesium atom is trapped, the more spread the energies of the quantum states in the valley are, and ultimately the faster the atom can be transported. Something similar can be seen in the example of the waiter: If he only fills the glasses half full (to the chagrin of the guests), he runs less risk that the champagne spills over as he accelerates and decelerates. However, the energetic freedom of a particle cannot be increased arbitrarily. We cant make our valley infinitely deep it would cost us too much energy, stresses Alberti.

The speed limit of Mandelstam and Tamm is a fundamental limit. However, one can only reach it under certain circumstances, namely in systems with only two quantum states. In our case, for example, this happens when the point of origin and destination are very close to each other, the physicist explains. Then the matter waves of the atom at both locations overlap, and the atom could be transported directly to its destination in one go, that is, without any stops in between almost like the teleportation in the Starship Enterprise of Star Trek.

In the foyer of the Institute of Applied Physics at the University of Bonn (from left): Thorsten Groh, Manolo Rivera Lam, Prof. Dr. Dieter Meschede and Dr. Andrea Alberti (all at a distance for corona safety reasons). Credit: Volker Lannert/Uni Bonn

However, the situation is different when the distance grows to several dozens of matter wave widths as in the Bonn experiment. For these distances, direct teleportation is impossible. Instead, the particle must go through several intermediate states to reach its final destination: The two-level system becomes a multi-level system. The study shows that a lower speed limit applies to such processes than that predicted by the two Soviet physicists: It is determined not only by the energy uncertainty, but also by the number of intermediate states. In this way, the work improves the theoretical understanding of complex quantum processes and their constraints.

The physicists findings are important not least for quantum computing. The computations that are possible with quantum computers are mostly based on the manipulation of multi-level systems. Quantum states are very fragile, though. They last only a short lapse of time, which physicists call coherence time. It is therefore important to pack as many computational operations as possible into this time. Our study reveals the maximum number of operations we can perform in the coherence time, Alberti explains. This makes it possible to make optimal use of it.

Reference: Demonstration of Quantum Brachistochrones between Distant States of an Atom by Manolo R. Lam, Natalie Peter, Thorsten Groh, Wolfgang Alt, Carsten Robens, Dieter Meschede, Antonio Negretti, Simone Montangero, Tommaso Calarco and Andrea Alberti, 19 February 2021, Physical Review X.DOI: 10.1103/PhysRevX.11.011035

The study was funded by the German Research Foundation (DFG) as part of the Collaborative Research Center SFB/TR 185 OSCAR. Funding was also provided by the Reinhard Frank Foundation in collaboration with the German Technion Society, and by the German Academic Exchange Service.

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Physicists Show a Speed Limit Also Applies in the Quantum World - SciTechDaily

If God wasnt able to break the laws of physics, she arguably wouldnt be as powerful as youd expect a supreme being to be. But if she could, why havent we seen any evidence of the laws of physics ever being broken in the universe?

By Monica Grady

"I still believed in God (I am now an atheist) when I heard the following question at a seminar, first posed by Einstein, and was stunned by its elegance and depth: If there is a God who created the entire universe andall of its laws of physics, does God follow Gods own laws? Or can God supersede his own laws, such as travelling faster than the speed of light and thus being able to be in two different places at the same time? Could the answer help us prove whether or not God exists or is this where scientific empiricism and religious faith intersect, withno true answer? " David Frost, 67, Los Angeles.

*

I was in lockdown when I received this question and was instantly intrigued. Its no wonder about the timing tragic events, such as pandemics, often cause us to question the existence of God: if there is a merciful God, why is a catastrophe like this happening? So the idea that God might be bound by the laws of physics which also govern chemistry and biology and thus the limits of medical science was an interesting one to explore.

If God wasnt able to break the laws of physics, she arguably wouldnt be as powerful as youd expect a supreme being to be. But if she could, why havent we seen any evidence of the laws of physics ever being broken in the universe?

***

Image via The Conversation

This article is part ofThe Conversations new series,Lifes Big Questions, co-published with BBC Future. The series seeks to answer questions about life, love, death and the universe, with the help of professional researchers who have dedicated their lives to uncovering new perspectives on the questions that shape our lives.

***

To tackle the question, lets break it down a bit. First, can God travel faster than light? Lets just take the question at face value. Light travels at an approximate speed of 3 x 105 kilometres every second, or 186,000 miles per second. We learn at school that nothing can travel faster than the speed of light not even the USS Enterprise in Star Trek when its dilithium crystals are set to max.

But is it true? A few years ago, a group of physicists posited that particles called tachyons travelled above light speed. Fortunately, their existence as real particles is deemed highly unlikely. If they did exist, they would have an imaginary mass and the fabric of space and time would become distorted leading to violations of causality (and possibly a headache for God).

It seems, so far, that no object has been observed that can travel faster than the speed of light. This in itself does not say anything at all about God. It merely reinforces the knowledge that light travels very fast indeed.

Things get a bit more interesting when you consider how far light has travelled since the beginning. Assuming a traditional big bang cosmology and a light speed of 3 x 105 km/s, then we can calculate that light has travelled roughly 1024 km in the 13.8 billion years of the universes existence. Or rather, the observable universes existence.

The universe is expanding at a rate of approximately 70km/s per Mpc (1 Mpc = 1 Megaparsec ~ 30 million km), so current estimates suggest that the distance to the edge of the universe is 46 billion light years. As time goes on, the volume of space increases, and light has to travel for longer to reach us.

There is a lot more universe out there than we can view, but the most distant object that we have seen is a galaxy, GN-z11, observed by the Hubble Space Telescope. This is approximately 1023 km or 13.4 billion light years away, meaning that it has taken 13.4 billion years for light from the galaxy to reach us. But when the light set off, the galaxy was only about 3 billion light years away from our galaxy, the Milky Way.

We cannot observe or see across the entirety of the universe that has grown since the big bang because insufficient time has passed for light from the first fractions of a second to reach us. Some argue that we therefore cannot be sure whether the laws of physics could be broken in other cosmic regions perhaps they are just local, accidental laws. And that leads us on to something even bigger than the universe.

The multiverse

Many cosmologists believe that the universe may be part of a more extended cosmos, a multiverse, where many different universes co-exist but dont interact. The idea of the multiverse is backed by the theory of inflation the idea that the universe expanded hugely before it was 10-32 seconds old. Inflation is an important theory because it can explain why the universe has the shape and structure that we see around us.

But if inflation could happen once, why not many times? We know from experiments that quantum fluctuations can give rise to pairs of particles suddenly coming into existence, only to disappear moments later. And if such fluctuations can produce particles, why not entire atoms or universes? Its been suggested that, during the period of chaotic inflation, not everything was happening at the same rate quantum fluctuations in the expansion could have produced bubbles that blew up to become universes in their own right.

Are we living in a bubble universe? Image via The Conversation/Juergen Faelchle/Shutterstock

But how does God fit into the multiverse? One headache for cosmologists has been the fact that our universe seems fine-tuned for life to exist. The fundamental particles created in the big bang had the correct properties to enable the formation of hydrogen and deuterium substances that produced the first stars.

The physical laws governing nuclear reactions in these stars then produced the stuff that lifes made of carbon, nitrogen and oxygen. So how come all the physical laws and parameters in the universe happen to have the values that allowed stars, planets and ultimately life to develop?

Some argue its just a lucky coincidence. Others say we shouldnt be surprised to see biofriendly physical laws they after all produced us, so what else would we see? Some theists, however, argue it points to the existence of a God creating favourable conditions.

But God isnt a valid scientific explanation. The theory of the multiverse, instead, solves the mystery because it allows different universes to have different physical laws. So its not surprising that we should happen to see ourselves in one of the few universes that could support life. Of course, you cant disprove the idea that a God may have created the multiverse.

This is all very hypothetical, and one of the biggest criticisms of theories of the multiverse is that because there seem to have been no interactions between our universe and other universes, then the notion of the multiverse cannot be directly tested.

Quantum weirdness

Now lets consider whether God can be in more than one place at the same time. Much of the science and technology we use in space science is based on the counter-intuitive theory of the tiny world of atoms and particles known as quantum mechanics.

The theory enables something called quantum entanglement: spookily connected particles. If two particles are entangled, you automatically manipulate its partner when you manipulate it, even if they are very far apart and without the two interacting. There are better descriptions of entanglement than the one I give here but this is simple enough that I can follow it.

Imagine a particle that decays into two sub-particles, A and B. The properties of the sub-particles must add up to the properties of the original particle this is the principle of conservation. For example, all particles have a quantum property called spin roughly, they move as if they were tiny compass needles. If the original particle has a spin of zero, one of the two sub-particles must have a positive spin and the other a negative spin, which means that each of A and B has a 50 percent chance of having a positive or a negative spin. (According to quantum mechanics, particles are by definition in a mix of different states until you actually measure them.)

The properties of A and B are not independent of each other they are entangled even if located in separate laboratories on separate planets. So if you measure the spin of A and you find it to be positive. Imagine a friend measured the spin of B at exactly the same time that you measured A. In order for the principle of conservation to work, she must find the spin of B to be negative.

But and this is where things become murky like sub-particle A, B had a 50:50 chance of being positive, so its spin state became negative at the time that the spin state of A was measured as positive. In other words, information about spin state was transferred between the two sub-particles instantly. Such transfer of quantum information apparently happens faster than the speed of light. Given that Einstein himself described quantum entanglement as spooky action at a distance, I think all of us can be forgiven for finding this a rather bizarre effect.

So there is something faster than the speed of light after all: quantum information. This doesnt prove or disprove God, but it can help us think of God in physical terms maybe as a shower of entangled particles, transferring quantum information back and forth, and so occupying many places at the same time? Even many universes at the same time?

Spooky action. Image via The Conversation/ Jurik Peter/Shutterstock

I have this image of God keeping galaxy-sized plates spinning while juggling planet-sized balls tossing bits of information from one teetering universe to another, to keep everything in motion. Fortunately, God can multitask keeping the fabric of space and time in operation. All that is required is a little faith.

Has this essay come close to answering the questions posed? I suspect not: if you believe in God (as I do), then the idea of God being bound by the laws of physics is nonsense, because God can do everything, even travel faster than light. If you dont believe in God, then the question is equally nonsensical, because there isnt a God and nothing can travel faster than light. Perhaps the question is really one for agnostics, who dont know whether there is a God.

This is indeed where science and religion differ. Science requires proof, religious belief requires faith. Scientists dont try to prove or disprove Gods existence because they know there isnt an experiment that can ever detect God. And if you believe in God, it doesnt matter what scientists discover about the universe any cosmos can be thought of as being consistent with God.

Our views of God, physics or anything else ultimately depends on perspective. But lets end with a quotation from a truly authoritative source. No, it isnt the bible. Nor is it a cosmology textbook. Its from Reaper Man by Terry Pratchett:

Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it.

Monica Grady is a Professor of Planetary and Space Sciences atThe Open University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Can the laws of Physics help settle the debate over the existence of God? - Firstpost

Upon recommendation by the Office of Senior Vice President for Academic Affairs and Provost Britt Rios-Ellis, and with support of President Ora Hirsch Pescovitz, the Oakland University Board of Trustees unanimously approved a request to appoint David Garfinkle, Ph.D.; Zissimos Mourelatos, Ph.D.; and Barbara Oakley, Ph.D. to the rank of Distinguished Professor at the formal February meeting. The appointment is effective August 15, 2021.

A selection committee of their peers recommended Professor Garfinkle, Professor Mourelatos, and Professor Oakley for consideration of these appointments and wrote letters of support for the nominations. The provosts office also did an extensive review of each professors body of work.

I want to thank (the Board of Trustees) very much for this honor, said Garfinkle, a professor in the Department of Physics. I also want to thank the university for supporting us through the years in our quest to do our research, teach our students, and reach out to the wider world beyond our campus.

Professor Garfinkle is an outstanding scientist and leader in the field of general relativity, especially its application to black holes and the big bang, and has a worldwide reputation as an expert on space-time singularities. His work has been funded by the National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, and the Research Corporation. He is a Fellow of the American Physical Society, a member of the Foundational Questions Institute, an associate of the Cosmology and Gravity Program of the Canadian Institute for Advanced Research, and a two-time Kavil Institute of Theoretical Physics scholar.

Garfinkle also is a versatile teacher who teaches courses in introductory physics, astronomy, modern physics, mathematical methods for physicists, numerical methods of physicists, mechanics, electricity and magnetism, quantum mechanics, thermodynamics, and nuclear physics many at both the undergraduate and graduate levels.

Professor Garfinkle is highly respected by his OU colleagues, who have on numerous occasions expressed their admiration of his academic stamina over the years and describe him as a model example of faculty who should be awarded the rank of distinguished professor, Rios-Ellis said.

Professor Mourelatos joined Oakland University in 2003 after an 18-year career at the General Motors Research and Development Center. As a world-renowned expert in the areas of design under uncertainty, reliability and safety, random vibrations, and noise, and vibration and harshness, his research contributions are nationally and internationally acclaimed. He is a Fellow of the American Society of Mechanical Engineers and the Society of Automotive Engineers.

Mourelatos is also the author of a book, multiple book chapters and more than 220 journal and conference papers. His work has been supported, among others, by the U.S. Army, the National Science Foundation, General Motors, Chrysler, General Dynamics Land Systems, Federal Mogul, and Beta CAE Systems.

His extensive and impactful research, external funding, hands-on commitment to developing the next generation of engineers and engineering faculty, and service to the profession merit Professor Mourelatos being awarded the rank of distinguished professor, Rios-Ellis said.

Mourelatos, a professor in the Mechanical Engineering Department, said he was honored and humbled by the appointment.

I would like to thank our Dean, Louay Chamra, for supporting me over the years and for nominating me for this particular honor, and also the Provost and the selection committee, he said. I would also like to thank all my graduate students over the years. For the past 20 years, theyve worked for hard for me to be in this position today. Last, but not least, I would like to thank Oakland University. Its a wonderful place; a very dynamic environment with many opportunities for flexibility. I think we have a great future.

Professor Oakley is both a revolutionary and true innovator in the area of pedagogy and is recognized as one of the worlds leading experts in learning, especially in the STEM (Science, Technology, Engineering and Mathematics) disciplines, and in the design of high-quality online pedagogical materials. Since joining Oakland University in 1998, she has made significant contributions as a productive scholar in the areas of STEM pedagogy, neuroscience and social behavior. Her books have been translated into over 20 different languages around the world.

She has pioneered important work that has significantly helped the Academy understand what impacts a persons interest in subject matter, along with what affects their ability to master mentally difficult material, Rios-Ellis said. It is truly impressive that of the 10,000 MOOCs (Massive Open Online Courses) currently available worldwide, her course, Learning How to Learn, is the worlds most popular with over 3 million registered learners from over 200 countries.

In recognition of her exemplary course materials and approach, Oakley was honored as Courseras Inaugural Innovation Instructor in 2015, is the recipient of the IEEE William E. Sayle II Award for Achievement in Education, the Theo C. Pilkington Award for Biomedical Engineering Education, Michigan Distinguished Professor of the Year, and the Oakland University Teaching Excellence Award.

My department chair, Dr. Robert Van Til, has done a lot to support my work over the years, said Oakley, a professor of Industrial and Systems Engineering at OU. I would also like to extend my appreciation to President Pescovitz for her great vision for our university.

The Distinguished Professor recognition includes a one-time salary stipend of $2,500 plus an annual supplies and services allocation of $1,500, up to five years, to be paid from the provosts discretionary fund.

Established in 1988 by the Oakland University Board of Trustees, the rank of Distinguished Professor is conferred on eminent faculty members for the duration of their service at Oakland. According to the criteria for Distinguished Professor status, the individual must be preeminent in at least one of three categories: scholarship, teaching, or public or professional service. This distinction has been conferred on a small and highly select group of outstanding individuals. Honorees are selected by the Provost and the Distinguished Professor Advisory Committee.

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OU appoints three to rank of Distinguished Professor - 2021 - Office of the Provost - News - OU Magazine - News at OU

"Our region is already a world leader in quantum science and technology, and the MQA is working to expand its impact in the design, building and commercialization of quantum technologies, and to create a skilled, diverse quantum workforce. - University of Maryland President Darryll J. Pines

COLLEGE PARK, Md. (PRWEB) February 19, 2021

The Mid-Atlantic Quantum Alliancea rapidly growing hub of quantum technology research, development, innovation and education organized and facilitated by the University of Marylandhas added 10 new members over the past year for a total of 24 university, government and industry partners. Together these MQA members are building a vibrant and diverse ecosystem designed to foster U.S. and regional leadership in the coming quantum technology revolution.

The new members of the Mid-Atlantic Quantum Alliance (MQA) https://mqa.umd.edu/ are: the National Institute of Standards & Technology (NIST), IBM, Protiviti, Quantopo, Quaxys, Bowie State University, Georgetown University, Pittsburgh Quantum Institute, University of Delaware, and Virginia Tech.

The additions expand the power, diversity, and geographical coverage of an already strong consortium of quantum scientists and engineers in academia, national laboratories, and industry that was formally launched on January 30, 2020, as the Maryland Quantum Alliance. The MQA was recently renamed the Mid-Atlantic Quantum Alliance to reflect its larger, more inclusive scope.

We are very pleased to welcome new partners to the Mid-Atlantic Quantum Alliance. said University of Maryland President Darryll J. Pines. "Our region is already a world leader in quantum science and technology, and the MQA is working to expand its impact in the design, building and commercialization of quantum technologies, and to create a skilled, diverse quantum workforce. This work is essential to power the coming quantum revolution in computing, communication, sensing, materials and many other areas."

For the past year, Mid-Atlantic Quantum Alliance workgroups have been creating ways for MQA members to more easily collaborate, share resources, facilities, equipment, expertise and data, team-up to pursue opportunities, and educate the public about the promise of the second quantum revolution. The expanding alliance has built a powerful forum for its members to engage and work together, not only on quantum science and technology R&D, but also on quantum training, education and global thought leadership. The MQA recently expanded the number and size of its workgroups in order to launch several new initiatives in its second year. These will showcase its technical leadership on the global stage, support quantum commercialization and entrepreneurship, and expand the quantum talent pipeline.

"MQA members' wealth of relevant expertise and Marylands concentration of world-leading quantum institutes with cutting-edge facilities and research, made this the ideal place to launch our new quantum technologies company, said Alan Salari, founder and CEO of Quaxys MQAs newest member. We are developing the new generation of hardware systems, especially at microwave frequencies,used for control and measurement of quantum bits, the basic unit of information in quantum computing. Quaxys is committed to solving the most challenging technical hurdles to quantum technologies. And we are excited to collaborate with experts from the University of Maryland and other MQA members in our work to bring the best of such technology to the market in the shortest time."

The Mid-Atlantic Quantum Alliance is collaboratively working to empower the region and nation to lead the unfolding second quantum revolution, which is expected to bring transformative advances in computing, communication, sensing, materials and many other areas. Alliance members have formally agreed to work together to inclusively advance the regional quantum ecosystem in a host of ways, including:

raising public awareness of quantum opportunities and potential, driving new quantum science discovery, developing pioneering quantum technologies, supporting quantum entrepreneurship, and startup companiestraining a diverse, world class quantum workforce.

We are excited to be a part of the Maryland Quantum Alliance (MQA), said Bowie State University Professor Chaobin Liu. We expect that MQA will create opportunities for BSU students to leverage the world-class quantum expertise, educational resources and career opportunities in the region and to fully participate in the second quantum revolution, said Liu, whose research and teaching focuses on probability theory and mathematical statistics, Mathematical physics and quantum computation. Bowie State University, Marylands first historically black public university, supports the regions workforce and economy by engaging in strategic partnerships, research, and public service to benefit local, state, national, and global communities.

Current specific goals of the MQA include: accelerating the strong quantum innovation by and among alliance members, and across the Mid-Atlantic regionpromoting interdisciplinary, applied & translational quantum tech research and commercialization efforts & outcomesmaking relevant quantum expertise & tech easier to find & accesssharing resources and identifying regional research infrastructure needs & opportunitiesbuilding a quantum workforce byfacilitating curriculum sharing & access to unique equipment/labs/expertisecreating unique shared experiential learning programs elevating diversity & inclusion as a core part alliance effortsconnecting/amplifying public & K-12 education campaignsbuilding international partnerships

Building and expanding diverse collaborations across different types of organizations are the foundation for a vibrant quantum economy within the region, which is the prime purpose of the MQA, said John Sawyer, MQA Interim Executive Director, and Director of Strategic Research Initiatives at the University of Maryland. Our members work together to align basic and applied quantum science with real-world needs and requirements, enable more rapid discovery of creative solutions, and equitably create the necessary infrastructure and workforce to scale up quantum technologies.

University of Maryland Quantum LeadershipThe University of Maryland is the facilitating institution for, and a leader of the Mid-Atlantic Quantum Alliance. Long recognized as a national and world leader in quantum science and technology, UMD hosts five collaborative research centers focused on different aspects of quantum science and technology: The Joint Quantum Institute (JQI) and the Joint Center for Quantum Information and Computer Science (QuICS) are collaborations with the National Institute of Standards and Technology. The Quantum Technology Center (QTC) a collaboration between the Clark School of Engineering, College of Computer, Mathematical, and Natural Sciences, and the Army Research Laboratory, brings together UMD engineers and physicists to work on translating quantum physics into transformational new technologies. The Condensed Matter Theory Center has made pioneering contributions to topological approaches to quantum computing, and the Quantum Materials Center explores superconductors and novel quantum materials to enable new technology devices.https://umdrightnow.umd.edu/news/mid-atlantic-quantum-alliance-expands-impact-and-reach-addition-10-new-partners

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Mid-Atlantic Quantum Alliance Expands Impact and Reach with Addition of 10 New Partners - PR Web