Category Archives: Quantum Physics
Quantum Theory May Twist Cause And Effect Into Loops, With Effect Causing The Cause – ScienceAlert
Causalityis one of those difficult scientific topics that can easily stray into the realm ofphilosophy.
Science's relationship with the concept started out simply enough: an event causes another event later in time. That had been the standard understanding of the scientific community up until quantum mechanics was introduced.
Then, with the introduction of the famous "spooky action at a distance" that is a side effect of the concept ofquantum entanglement, scientists began to question that simple interpretation of causality.
Now, researchers at the Universit Libre de Bruxelles (ULB) and theUniversity of Oxfordhave come up with a theory that further challenges that standard view of causality as a linear progress from cause to effect.
In their new theoretical structure, cause and effect can sometimes take place in cycles, with the effect actually causing the cause.
Thequantum realmitself as it is currently understood is inherently messy.
There is no true understanding of things at that scale, which can be thought of better as a set of mathematical probabilities rather than actualities.These probabilities do not exactly lend themselves well to the idea of a definite cause and effect interaction between events either.
The researchers further muddied the waters using a tool known as aunitary transformation.
Simply put, a unitary transformation is a fudge used to solve some of the math that is necessary to understand complex quantum systems. Using it makes solving the famousSchrodinger equationachievable using real computers.
To give a more complete explanation requires delving a bit into the "space" that quantum mechanics operates in.
In quantum mechanics, time is simply another dimension that must be accounted for similarly to how the usual three dimensions of what we think of as linear space are accounted for. Physicists usually use another mathematical tool called aHamiltonianto solve Schrodinger's equation.
A Hamiltonian, though a mathematical concept, is often time-dependent. However, it is also the part of the equation that is changed when a unitary transformation is introduced.
As part of that action, it is possible to eliminate the time dependency of the Hamiltonian, to make it such that, instead of requiring time to go a certain direction (ie., for action and reaction to take place linearly), the model turns more into a circle than a straight line, with action causing reaction and reaction causing action.
If this isn't all confusing enough, there are some extremely difficult to conceive of implications of this model (and to be clear, from a macro level, it is just a model).
One important facet is that this finding has little to no relevance to everyday cause and effect.
The causes and effects that would be cyclical in this framework "are not local in spacetime", according to thepress releasefrom ULB, so they are unlikely to have any impact on day to day life.
Even if it doesn't have any everyday impact now, this framework could hint at acombined theoryof quantum mechanics and general relativity that has been the most sought after prize in physics for decades.
If that synthesis is ever fully realized, there will be more implications for everyday life than just the existential questions of whether we are actually in control of our own actions or not.
This article was originally published by Universe Today. Read the original article.
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Quantum Theory May Twist Cause And Effect Into Loops, With Effect Causing The Cause - ScienceAlert
Extracting information stored in 100,000 nuclear quantum bits – Advanced Science News
Researchers were able to detect a "needle" of highly fragile quantum information in a "haystack" of nuclei.
Image credit: Getty Images/iStockphoto
Researchers have found a way to use light and a single electron to communicate with a cloud of quantum bits and sense their behaviour, making it possible to detect a single quantum bit in a dense cloud.
The researchers, from the University of Cambridge, were able to inject a needle of highly fragile quantum information in a haystack of 100,000 nuclei. Using lasers to control an electron, the researchers could then use that electron to control the behaviour of the haystack, making it easier to find the needle. They were able to detect the needle with a precision of 1.9 parts per million: high enough to detect a single quantum bit in this large ensemble.
The technique makes it possible to send highly fragile quantum information optically to a nuclear system for storage, and to verify its imprint with minimal disturbance, an important step in the development of a quantum internet based on quantum light sources. The results are reported in the journal Nature Physics.
The first quantum computers which will harness the strange behaviour of subatomic particles to far outperform even the most powerful supercomputers are on the horizon. However, leveraging their full potential will require a way to network them: a quantum internet. Channels of light that transmit quantum information are promising candidates for a quantum internet, and currently there is no better quantum light source than the semiconductor quantum dot: tiny crystals that are essentially artificial atoms.
However, one thing stands in the way of quantum dots and a quantum internet: the ability to store quantum information temporarily at staging posts along the network.
The solution to this problem is to store the fragile quantum information by hiding it in the cloud of 100,000 atomic nuclei that each quantum dot contains, like a needle in a haystack, said Professor Mete Atatre from Cambridges Cavendish Laboratory, who led the research. But if we try to communicate with these nuclei like we communicate with bits, they tend to flip randomly, creating a noisy system.
The cloud of quantum bits contained in a quantum dot dont normally act in a collective state, making it a challenge to get information in or out of them. However, Atatre and his colleagues showed in 2019 that when cooled to ultra-low temperatures also using light, these nuclei can be made to do quantum dances in unison, significantly reducing the amount of noise in the system.
Now, they have shown another fundamental step towards storing and retrieving quantum information in the nuclei. By controlling the collective state of the 100,000 nuclei, they were able to detect the existence of the quantum information as a flipped quantum bit at an ultra-high precision of 1.9 parts per million: enough to see a single bit flip in the cloud of nuclei.
Technically this is extremely demanding, said Atatre, who is also a Fellow of St Johns College. We dont have a way of talking to the cloud and the cloud doesnt have a way of talking to us. But what we can talk to is an electron: we can communicate with it sort of like a dog that herds sheep.
Using the light from a laser, the researchers are able to communicate with an electron, which then communicates with the spins, or inherent angular momentum, of the nuclei.
By talking to the electron, the chaotic ensemble of spins starts to cool down and rally around the shepherding electron; out of this more ordered state, the electron can create spin waves in the nuclei.
If we imagine our cloud of spins as a herd of 100,000 sheep moving randomly, one sheep suddenly changing direction is hard to see, said Atatre. But if the entire herd is moving as a well-defined wave, then a single sheep changing direction becomes highly noticeable.
In other words, injecting a spin wave made of a single nuclear spin flip into the ensemble makes it easier to detect a single nuclear spin flip among 100,000 nuclear spins.
Using this technique, the researchers are able to send information to the quantum bit and listen in on what the spins are saying with minimal disturbance, down to the fundamental limit set by quantum mechanics.
Having harnessed this control and sensing capability over this large ensemble of nuclei, our next step will be to demonstrate the storage and retrieval of an arbitrary quantum bit from the nuclear spin register, said co-first author Daniel Jackson, a PhD student at the Cavendish Laboratory.
This step will complete a quantum memory connected to light a major building block on the road to realizing the quantum internet, said co-first author Dorian Gangloff, a Research Fellow at St Johns College.
Besides its potential usage for a future quantum internet, the technique could also be useful in the development of solid-state quantum computing.
Reference: D. M. Jackson, et al, Quantum sensing of a coherent single spin excitation in a nuclear ensemble, Nature Physics (2021). DOI: 10.1038/s41567-020-01161-4
Excerpt from:
Extracting information stored in 100,000 nuclear quantum bits - Advanced Science News
Light and a Single Electron Used to Detect Quantum Information Stored in 100,000 Nuclear Quantum Bits – SciTechDaily
Researchers have found a way to use light and a single electron to communicate with a cloud of quantum bits and sense their behavior, making it possible to detect a single quantum bit in a dense cloud.
The researchers, from the University of Cambridge, were able to inject a needle of highly fragile quantum information in a haystack of 100,000 nuclei. Using lasers to control an electron, the researchers could then use that electron to control the behavior of the haystack, making it easier to find the needle. They were able to detect the needle with a precision of 1.9 parts per million: high enough to detect a single quantum bit in this large ensemble.
The technique makes it possible to send highly fragile quantum information optically to a nuclear system for storage, and to verify its imprint with minimal disturbance, an important step in the development of a quantum internet based on quantum light sources. The results are reported in the journalNature Physics.
The first quantum computers which will harness the strange behavior of subatomic particles to far outperform even the most powerful supercomputers are on the horizon. However, leveraging their full potential will require a way to network them: a quantum internet. Channels of light that transmit quantum information are promising candidates for a quantum internet, and currently there is no better quantum light source than the semiconductor quantum dot: tiny crystals that are essentially artificial atoms.
However, one thing stands in the way of quantum dots and a quantum internet: the ability to store quantum information temporarily at staging posts along the network.
The solution to this problem is to store the fragile quantum information by hiding it in the cloud of 100,000 atomic nuclei that each quantum dot contains, like a needle in a haystack, said Professor Mete Atatre from Cambridges Cavendish Laboratory, who led the research. But if we try to communicate with these nuclei like we communicate with bits, they tend to flip randomly, creating a noisy system.
The cloud of quantum bits contained in a quantum dot dont normally act in a collective state, making it a challenge to get information in or out of them. However, Atatre and his colleagues showed in 2019 that when cooled to ultra-low temperatures also using light, these nuclei can be made to do quantum dances in unison, significantly reducing the amount of noise in the system.
Now, they have shown another fundamental step towards storing and retrieving quantum information in the nuclei. By controlling the collective state of the 100,000 nuclei, they were able to detect the existence of the quantum information as a flipped quantum bit at an ultra-high precision of 1.9 parts per million: enough to see a single bit flip in the cloud of nuclei.
Technically this is extremely demanding, said Atatre, who is also a Fellow of St Johns College. We dont have a way of talking to the cloud and the cloud doesnt have a way of talking to us. But what we can talk to is an electron: we can communicate with it sort of like a dog that herds sheep.
Using the light from a laser, the researchers are able to communicate with an electron, which then communicates with the spins, or inherent angular momentum, of the nuclei.
By talking to the electron, the chaotic ensemble of spins starts to cool down and rally around the shepherding electron; out of this more ordered state, the electron can create spin waves in the nuclei.
If we imagine our cloud of spins as a herd of 100,000 sheep moving randomly, one sheep suddenly changing direction is hard to see, said Atatre. But if the entire herd is moving as a well-defined wave, then a single sheep changing direction becomes highly noticeable.
In other words, injecting a spin wave made of a single nuclear spin flip into the ensemble makes it easier to detect a single nuclear spin flip among 100,000 nuclear spins.
Using this technique, the researchers are able to send information to the quantum bit and listen in on what the spins are saying with minimal disturbance, down to the fundamental limit set by quantum mechanics.
Having harnessed this control and sensing capability over this large ensemble of nuclei, our next step will be to demonstrate the storage and retrieval of an arbitrary quantum bit from the nuclear spin register, said co-first author Daniel Jackson, a PhD student at the Cavendish Laboratory.
This step will complete a quantum memory connected to light a major building block on the road to realising the quantum internet, said co-first author Dorian Gangloff, a Research Fellow at St Johns College.
Besides its potential usage for a future quantum internet, the technique could also be useful in the development of solid-state quantum computing.
Reference: 15 February 2021, Nature Physics.DOI: 10.1038/s41567-020-01161-4
The research was supported in part by the European Research Council (ERC), the Engineering and Physical Sciences Research Council (EPSRC) and the Royal Society.
Original post:
IBM Adds Future Developer And Software Details To Its Quantum Roadmap – Forbes
IBM Quantum development roadmap.
In late 2020, IBM released its first long-term quantum roadmap, showing how IBM's quantum architecture, hardware and qubit count would change over the next few years. IBM plans on evolving its present-day small-scale, noisy quantum computers to a near-term intermediate 1121-qubit machine named Condor. Once perfected, Condor will become the future building block of a larger fault-tolerant quantum computer with millions of qubits.
Qubits represent the fundamental unit of information in quantum computers. Unlike classical computing bits, which can only represent either a one or a zero, qubits can also be a one or a zero or a superposition of both values. Superposition is a fundamental feature of quantum mechanics that plays an essential role in quantum computing.
Last week, IBM released a new and more descriptive technology roadmap. It overlays an expanded timeline of future applications, new Qiskit software and developer capabilities on top of the earlier 2020 hardware roadmap.
According to Jay Gambetta, IBM Fellow and Vice President Quantum Computing, IBM recognized more future plans were needed in its roadmap. "Ultimately software is really tied to the hardware. What I wanted to do this year was to put some context around where we see the software going, and then bring it together with more of an application focus for the user." Gambetta went on to say he believes quantum computing will eventually be able to solve "big problems" in the areas of natural sciences, optimization, finance and machine learning.
Quantum solutions to problems in these four areas will ultimately touch and influence almost every facet of our lives. The first working 2-qubit quantum computer was announced in 1998. Since then, quantum scientists have dreamed of building a universal fault-tolerant quantum computer with millions of qubits. However, for many years, some scientists didn't believe it could be done.
New IBM 2021 development roadmap
IBM's hardware and qubit counts remain unchanged from its first 2020 roadmap. However, for 2021 and beyond, IBM will focus its efforts on developing software that allows circuits to run faster and makes it easier for developers and industry specialists to use quantum. Moreover, these software improvements will happen in a future environment where integrated classical computers and quantum computers will provide a seamless quantum solution. After a careful review, it is clear that IBM is building a complete software ecosystem around users of its quantum cloud. Gambetta believes that for technology to be adopted, IBM needs to make it as frictionless as possible. Moreover, he believes developers shouldn't have to learn new languages. Gambetta says quantum programming must be integrated into developers' existing code and easily called with a cloud quantum API or service for new quantum technology to be successful.
Software tailored to developers
IBM Quantum user stack
In 2016, IBM provided the world's first cloud access to a superconducting quantum processor with five qubits. Almost immediately after launching the system, papers were published based on research performed on the system. Since then, quantum researchers have made significant contributions to the evolution of quantum computing.
Today, IBM has over 20 quantum computers available on the cloud, with over half offering free access. Usage on IBM's quantum cloud is staggering.Over 1.3 billion quantum circuits are run daily, and democratized cloud access for researchers has resulted in over 300 technical papers. From the time IBM's first quantum computer became available on the cloud until now, there have been over 700 billion quantum cloud executions.
According to the roadmap, IBM is creating a user-friendly software approach for developers which will facilitate access to future quantum services. The company will be customizing access to its quantum hardware based on specific interests, needs and existing coding environment of developers. Robert Sutor, Vice President of IBM Quantum Ecosystem Development, said, "We have laid out a software approach heavily oriented towards developers. We feel strongly that a healthy user base will also be a guiding force that will help shape the future technical direction of quantum devices."
Qiskit is IBM's open-source quantum programming framework that allows researchers and developers to program quantum computers and classical simulators. IBM's primary goal is to increase its hardware capacity while making its quantum programs simple to use for the largest number and greatest variety of developers possible. Each type of developer has its own separate and distinct needs.
The following developer descriptions were derived from an earlier IBM paper and edited for clarity. IBM plans on creating a "frictionless" software ecosystem for each type of developer, offering access in a form familiar to them. IBM also intends on providing developers access to data associated with that work level, such as coherence times, qubit frequencies, crosstalk and error rates for calibrated quantum gates and operations.
Future IBM software developments
Qiskit Runtime
Circuits provide instructions for quantum computers. In the early stages of quantum computing, it made sense for IBM to focus optimization efforts on improving circuit capacity and circuit quality. Leveraging these previous circuit improvements, IBM will be releasing a feature called Qiskit Runtime for kernel developers sometime in 2021.Runtime will provide faster circuits and allow programs to be stored and shared with other developers.
For example, running a chemistry algorithm today is a complicated process. Before executing any circuits, you must pick the plot points, choose the error mitigation and classical quantum optimization algorithms, then recast the problem to fit the quantum machine. Lastly, you need to consider how many shots are needed. Continuing this full loop allows the developer to do calculations on their classical computer using data from the quantum computer.
IBM plans to simplify the process by putting these steps together and then executing them close to the quantum processor. Lithium Hydride is a relatively small molecule that IBM uses as an example to illustrate runtime speedup. Current simulation of the molecule can require up to 100 days. Runtime will shorten the simulation to a day or two.
2021 Mid-Circuit Measurement and Reset
Measuring a qubit causes its superposition to collapse, revealing its state to be a one or a zero. That is why current measurements occur at the end of a quantum circuit. However, IBM has already introduced a new feature called mid-circuit measurement and reset (MCMR). MCMR allows measurement of a qubit at any point in the circuit and triggers other actions. Regardless of its measured state, the qubit is reset to 1 so that it becomes a known state, which allows it to be reused, making more efficient use of resources.MCMR can also be performed multiple times in a circuit.
2022 Dynamic Circuits
IBM has prototyped "smart circuits" called Dynamic Circuits that will be available in 2022.Dynamic circuits are circuits in which future states depend on outcomes of measurements that happen during the circuit.Dynamic circuits will allow branching actions such as the use of real-time classical processing to take place based on conditions within an existing circuit. Dynamic circuits can be useful for demonstrations of dynamic error correction, classical logic, developer assertions, and zero state preparations.IBM expects Dynamic circuits to be widely used and contribute to creating a wider pool of circuits available to developers.
Phase estimation of a given unitary
As shown in the above circuit diagrams, dynamic circuits using MCMR can also be used for a fundamental quantum algorithm called quantum phase estimation (QPE). Many algorithms use QPE because it has the potential to provide logarithmic speedup. Phase estimationis also an important part of period finding to factor numbers inShor's Algorithm (one of the most famous algorithms in quantum computing).Unfortunately, running quantum phase estimation requires many resources and many shots to obtain an accurate answer.
The above IBM illustration compares two methods of phase estimation: post-processing vs. real-time using dynamic circuits. The basic question for this scenario is which solution needs the least number of resources to obtain the answer with the specified accuracy? IBM researchers recently ran a version of the quantum phase estimation algorithm (iterative quantum phase estimation) with dynamic circuits. The researchers proved dynamic circuits took fewer resources than other methods. Once this feature becomes available, IBM believes dynamic circuits will become an essential software tool for kernel developers. Moreover, its use should produce many papers that advance its future use.
2023-2026
Hardware
According to the roadmap, a significant hardware milestone will occur in 2023. That's when IBM plans to introduce its 1121-qubit Condor quantum processor. The Condor will be preceded in 2021 by a 127-qubit Eagle processor and in 2022 by a 433-qubit Osprey processor. Even though 1121 qubits may sound like a monster by today's standards, we will need a machine that is thousands of times larger to fulfill quantum computing's true potential. Even so, the Condor should be able to do some useful work, perhaps even achieve quantum advantage for limited applications. This machine should allow IBM to make significant progress with error correction. The Condor will also help researchers develop and optimize a large qubit architecture to prepare for the million-qubit machine. Beyond 2026, IBM envisions having advanced control electronics and software that seamlessly integrate classical HPC and a fault-tolerant quantum computers with millions of qubits.
Software
IBM will begin releasing circuit libraries to provide kernel developers with tools to investigate algorithms that use large qubit hardware. According to the roadmap, advanced versions of dynamic circuits will be segmented, then reconstructed into larger circuits tailored to specific needs. Later, frequently run circuits can be used to create groups of pre-built quantum runtimes. These runtimes can be customized for specific industries, then called by APIs using common development frameworks. By this time, IBM believes its 2021's "frictionless" strategy will have attracted enough kernel and algorithm developers to produce a large body of usable research and algorithms. Both model developers and enterprise developers will benefit from this research, enabling them to explore quantum computing models without needing academic training in quantum physics.
Analyst notes:
Disclosure:Moor Insights & Strategy, like all research and analyst firms, provides or has provided paid research, analysis, advising, or consulting to many high-tech companies in the industry, includingIBM. The author holds no investment positions with any of the companies mentioned in this column.
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IBM Adds Future Developer And Software Details To Its Quantum Roadmap - Forbes
Physics – A Superconducting Qubit that Protects Itself – Physics
February 17, 2021• Physics 14, 25
A newly proposed superconducting circuit architecture employs a synthetic magnetic field to create a qubit that is intrinsically protected from noise.
Today, noise poses one of the biggest challenges for quantum computation efforts. Be it in the form of dissipated heat, electromagnetic radiation, or something else, noise can disrupt fragile quantum superpositions and lead to errors. The jury is still out on which approach will be most successful in protecting quantum information against noise, but the hope clearly lies in quantum error correction (QEC) protocols. Now, Martin Rymarz of RWTH Aachen University in Germany and colleagues have proposed a novel superconducting circuit implementation that realizes a QEC strategy in which robustness against noise is an intrinsic feature of the hardware [1]. This strategy, known as the Gottesman-Kitaev-Preskill (GKP) code, was proposed in 2001 [2]. However, implementing it with superconducting circuits has so far been impossible because it requires a large magnetic field. The newly proposed architecture circumvents this obstacle by employing a synthetic magnetic field, pushing the GKP protocol closer to a possible realization.
The noise processes that threaten quantum computing are assumed to be local, meaning that they act on specific parts of circuits, such as individual physical qubits. In the scaling-up approach to QEC, quantum information is encoded into multiple physical qubits that form each logical qubit used for the actual computation tasks. So even if one physical qubit is disrupted by noise, the information carried by the logical qubit will not be corrupted. In the exotic-state approach to QEC, each computational unit is a single oscillator, and the logical bits are represented by two special states of the oscillator, called nontrivial states, that are robust against local noise. The exotic-state technique employs continuous-variable systems, such as electromagnetic modes, which are initialized in states that are either robust by themselves (passive QEC) or can be stabilized via operations that do not affect the logical qubit (active QEC).
The GKP strategy is one example of the exotic-state approach [2]. In the GKP code, the exotic states are called grid states, which are superpositions of an oscillators position eigenstates [2]. The robustness to noise in an active GKP protocol stems from the fact that small shifts in the momentum and position of the oscillator can be identified and corrected before they can corrupt the logical information. An experimental demonstration of grid states was recently realized in a superconducting circuit architecture with an active QEC protocol [3]. A GKP code with passive QEC, however, has not yet been demonstrated. Compared to active QEC, which requires complicated operations for error recovery, a passive QEC approach promises to be more efficient and could be advantageous for scaling up to larger computing architectures, as it requires fewer physical units.
A prototypical implementation of a passive GKP code involves an electron confined to two dimensions in a large magnetic field. Realizing such a passive GKP-code design with superconducting circuit architectures is not straightforward. The design would require a magnetic field to interact with microwave photons, which are the oscillations of the electromagnetic field in the superconducting circuit. But photons are neutral particles and do not interact with magnetic fields in the same way that charged particles, such as electrons, do. Strategies for creating artificial magnetic fields that can interact with photons have been discussed and demonstrated in some superconducting systems [46]. The role of magnetic fields, whether real or artificial, in these systems is to break time-reversal symmetry, creating nonreciprocal circuits with multiple ports. The nonreciprocity means that the circuits process photons in a different way depending on which port they are injected into. This asymmetry can be exploited to build nonreciprocal devices that transmit microwave signals in one direction while blocking them in the reverse direction [6].
Rymarz and colleagues have proposed a way of utilizing synthetic magnetic fields, allowing for a superconducting qubit realization of the GKP code. They propose a system in which two superconducting anharmonic oscillators, called fluxonium circuits, are coupled via a gyrator, a device that can invert the current-voltage characteristics of a circuit element (Fig. 1). The asymmetric response of the gyrator implies a breaking of time-reversal symmetry like that produced by a magnetic field. The team shows that the ground states of the system correspond to the GKP code wordsthe grid states that are used to encode the logical information. The huge advantage here is that the logical qubit is constructed from the ground states of the systemin which the system will reside if no external energy is supplied. Leaving the ground state would corrupt the logical qubit, but it comes with an energy penalty, so the protection is naturally built in.
The researchers show that the proposed superconducting circuit simulates the model of an electron confined to a two-dimensional plane and subjected to a magnetic field. As such, the circuits energies resemble those of a quantum oscillator with discrete energy levels. For a given magnetic flux, the lowest-energy states can be used to encode the GKP code words.
A qualitative analysis of the circuit predicts a robustness against common noise sources, such as charge and flux noise, making it a promising passive-QEC candidate. Clearly, the characteristics of the circuit needed to implement the new scheme require improvements of existing technology. For example, the fluxonium circuit should have a very large inductance, which isnt currently attainable but will hopefully be possible in next generation designs. The proposed implementation of the hardware-encoded grid states represents a novel utilization of synthetic magnetism and a new application for gyrators based on the anomalous quantum Hall effect [7, 8]. It remains to be seen, however, whether these gyrators can successfully be married with two fluxonium circuits on-chip. Another question is whether an actively driven nonreciprocal on-chip device [5] could be a better alternative than a gyrator based on the anomalous quantum Hall effect.
This hardware-encoded GKP code implementation complements other ongoing efforts in designing intrinsically error-protected, superconducting circuit qubits, such as the realization of the 0 qubit [9] and the proposal of the doubly nonlinear qubit, or dualmon [10]. All designs come with challenging demands on the parameters of the employed materials and of the circuit elements. Encouragingly, the implementation proposed by Rymarz and colleagues comes within feasible reach of near-future technology. Realizing GKP code words using superconducting circuits is especially promising, as it makes it relatively straightforward to implement a subset of logic gates called Clifford gates, which are required for fault-tolerant computation [2, 3]. The realization of an intrinsically robust computation unit is only the first step on the complex path towards fault-tolerant quantum computation. But every new design pushes the field of superconducting circuits towards new horizons.
Anja Metelmann is an Emmy Noether research group leader in the Department of Theoretical Physics at the Free University Berlin in Germany. In 2012, she received her Ph.D. in physics from the Technical University Berlin in Germany. She spent her postdoctoral time in the Physics Department of McGill University in Montreal, and in the Department of Electrical Engineering at Princeton University.Her research interests lie in the fundamental aspects and applications of superconducting circuits and mechanical systems in the quantum regime. Part of her current research focuses on nonreciprocity as a resource for quantum information processing.
A small prototype of a drone-based quantum network has successfully relayed a quantum signal over a kilometer of free space. Read More
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Physics - A Superconducting Qubit that Protects Itself - Physics
Black Quantum Futurism receives the Knight Foundations new art and technology fellowship – WHYY
Another project of BQF is an ongoing community engagement effort called Community Futurisms. It first existed as a storefront in North Philadelphia where neighbors were invited inside to record oral histories, then imagine possible futures, and record those too.
For that project, BQF researched the history of Progress Plaza, which opened in 1968 in North Philadelphia near Temple University. It was the first African American-owned supermarket plaza in the country, owned by the Rev. Leon Sullivan. Sullivan was known internationally for his 1977 Sullivan Principles, which urged businesses with operations in then-apartheid South Africa to treat employees there the same way they treat their American employees, rather than abiding apartheid laws.
Inside Progress Plaza, Sullivans company had a garment factory and ran Progress Aerospace Enterprises, which manufactured parts for the aerospace industry. It was the first Black-owned aerospace business, which dovetails neatly with BQFs interest in space and technology.
Those two spaces employed young, unskilled Black youth in the community, and women. It was an amazing place. We see it as a retro-Afro-futurist project right in the middle of North Philly, said Phillips. We wanted to connect these legacies with the present, that 50-some years later were still struggling with fair housing issues. Were still seeing the same demographics around access to housing that we saw in 1968.
The COVID-19 pandemic has curtailed some of BQF projects over the last year, driving them to lean more heavily on internet technologies. They are planning new projects for later this year at the historic Hatfield House in Fairmount Park and at the Village of Arts and Humanities in North Philadelphia. Their extraordinary opportunity to do research at the Hadron super collider and the influx of cash from the Knight Foundation will allow them in the words of William Shatner to boldly go where no (wo)man has gone before.
Im a public interest attorney, Camae is a musician. Art costs money, you know. Its not a cheap practice, said Phillips. Were two Black women from North Philly who have not had the same ability to focus on our art practice in the same way as if we were classically trained or able to go to school for our art. To be able, in just a few years, to build our practice and get to this level is amazing.
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Black Quantum Futurism receives the Knight Foundations new art and technology fellowship - WHYY
Resolving to read more in 2021 – Powell Tribune
Pat Stuart
By Pat Stuart
The time has come and passed for New Years resolutions. But this doesnt preclude resolving to read more.
The possibilities are endless. In 2018, 1.6 million books were published. That figure includes self-published volumes and e-books. No way you cant find something that appeals.
This came to mind because CBS Sunday Morning ran a piece about an old fictional friend and a famous teen-aged heroine: Nancy Drew. Shes been with us for 90 years! Who knew. Various versions of her adventures have sold over 80 million copies, and the books are still coming. Some are sitting on my bookshelves.
Yikes. To think that my mother read Nancy Drew as a pre-teen, as did I, as did my daughter and as my grandsons would have done if theyd been girls. We all probably picked up tips on how to deal with the world of adults, how to be independent thinkers, how to be adventurous and risk-takers.
Midnight Library
Which brings me to one of this seasons acclaimed books, Midnight Library. A great title. Michael Haigs new novel has won rave reviews from the critics, but Im not quite sure why. The writing is mostly good and the plot line tantalizing in the abstract but, in sum, I found it far from the brilliant some critics proclaimed.
The almost middle-aged heroine herself is dull ... running, not walking, from every opportunity life offers until shes bricked herself into a lonely cell. No one wants to enter while theres nowhere she wants to go.
No surprise. She commits suicide ... and finds herself at a nexus between an infinite number of realities (think quantum physics) where every possible permutation of her life comes together. Here, she can sift through her regrets and live the experiences she might have had if only shed had the courage. Think purgatory, atonement and redemption.
I suspect were supposed to cheer when she learns what should be a teen years coming-of-age lesson: You take from this life what you put into it. Nancy Drew knew that.
D-Day Girls
Much, much better is a 2019 book that almost fell off a library shelf and into my hands. D-Day Girls by Sarah Rose is an extraordinarily well-written and researched non-fiction book about the women Britain sent into France to run spy rings, train saboteurs, blow up rail lines and power plants, and pave the way for an invasion.
The book treats us to belly-shaking wit along with a full range of other emotions as the author expertly draws us through the complexities and dangers of war-time, occupied France. Nor does she spare the spies and partisans while leaving their courage and heroism untouched. Ego trips, self-delusion, wishful thinking, laziness, romance its all there, too often leading to torture and death.
Its no secret that Im a fan of World War IIs espionage heroines who, if they survived, were rusticated to file rooms as what the men of the CIA dismissively called little old ladies in tennis shoes, and our hereditary memory.
Ive mentioned before that some of them were still around when I entered on duty. Now I wish Id visited the file rooms where they spent their last working days. In my own defense, I had no idea then of what theyd done or how brilliantly they had performed. They (and I) were victims of the post-WWII effort to put the war-time genie back in the bottle and women back in the kitchen.
(As an aside and as an example, John Stein a really superb operations officer and a generally supportive one who became Deputy Director for Operations strongly advised me for my own good early in our careers that Id be happier if I devoted myself to cooking for my husband, the way his wife Charlie did. No joke.)
As you can see, the acceptance of the D-Day womens accomplishments and the less spectacular and meaningful ones of my generation came only slowly. But a number of well-researched books this one by Sarah Rose as a superb example is changing that.
Life really is stranger and much more interesting than fiction.
The Night Watchman
Finally, Id like to mention Louise Erdrichs award-winning and much-praised 2020 book of fictionalized history, The Night Watchman. She, too, has a female character in a coming-of-age situation. But, what a difference from Michael Haigs colorless heroine or from the real women of D-Day!
Probably like most of you, I consider a book worth reading when I learn from it. And, learn I did.
For the first time in a long life, years of it lived in proximity to Indian reservations, I found myself walking in the footsteps of our first citizens. Erdrich brings her many characters to life in ways that allow us to come as close as possible to understanding them and to feel their joys and pains, their frustrations, ambitions and resignations. I loved every minute of the page-turning, superbly written read.
Maybe these arent the books for you. We all have our tastes in reading whether in digital or hard copy. Whatever yours might be, one of the easiest and most enjoyable resolutions you can make is to visit your local independent bookseller or your library online or on foot.
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Warp Drives Are No Longer Science Fiction – Applied Physics – Business Wire
NEW YORK--(BUSINESS WIRE)--Scientists at Applied Physics are excited to announce they have recently constructed the first model of physical warp drives.
Applied Physics is an independent group of scientists, engineers, and inventors that advise companies and governments on science and technology for both commercial and humanitarian applications.
In the organizations most recent news, the team at Applied Physics is announcing the first model of physical warp drives something that, until now, has only had a place in science fiction. The groups study was conducted in close contact with distinguished researchers in warp field mechanics, including receiving blessings from the esteemed Theoretical Physicist Miguel Alcubierre, with findings being published in the peer-reviewed journal, Classical and Quantum Gravity.
Many people in the field of science are aware of the Alcubierre Drive and believe that warp drives are unphysical because of the need for negative energy, says Lund University Astrophysicist and Scientist at Applied Physics, Alexey Bobrick. This, however, is no longer correct; we went in a different direction than NASA and others and our research has shown there are actually several other classes of warp drives in general relativity. In particular, we have formulated new classes of warp drive solutions that do not require negative energy and, thus, become physical.
While we still cant break the speed of light, we dont need to in order to become an interstellar species, says Gianni Martire, Scientist at Applied Physics. Our warp drive research has the potential to unite us all.
Both Bobrick and Martire are happy to provide further details about their work regarding warp drives to any interested party.
Paper breakdown by Dr. Sabine Hossenfelder: https://youtu.be/8VWLjhJBCp0
Fact Sheet and Media Assets: http://lmbd.co/warp
For more information about Applied Physics, please visit https://AppliedPhysics.org
About Applied Physics
Applied Physics consists of diverse international minds with advanced knowledge in nearly every field of physics, computer science, and engineering. With offices in neutral Sweden, and being a Public Benefit Company in the United States, Applied Physics is structured to be wholly independent of any academic or government body, allowing the institute to pursue research solely for the public good.
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Warp Drives Are No Longer Science Fiction - Applied Physics - Business Wire
RI local and star of ‘Ghost Hunters’ + ‘Kindred Spirits’ on her search for the paranormal – The Providence Journal
G. Wayne Miller|The Providence Journal
PROVIDENCE Pretty much everyone has a ghost story. Some are comforting. Others amuse. Still others terrify. But not everyone has made a flourishing career ofthem.
Rhode Island resident Amy Bruni has.
You may have watched paranormal investigator Bruni, formerly of the popular TV show Ghost Hunters, and now as co-star of the Travel Channels hit show Kindred Spirits.
You may have read her USA TODAY best-selling book, Life with the Afterlife: 13 Truths I Learned about Ghosts, which chronicles her adventures, including her investigations of ghosts inside the old Biltmore Hotel and the house in Burrillville that was the basis for the 2013 supernatural movie The Conjuring.
More: Would you dare to stay at The Conjuring house in Burrillville?
And now you can watch Bruni discuss her life and work this week on Story in the Public Square,a Providence Journal and Pell Center partnership that airs on SiriusXM and public television stations across the country.
Bruni began by discussing her childhood in California in a house that was haunted with a mother and father who both were interested in, and did not fear, the supernatural.
The way they talked about it was so matter of fact, Bruni said. They were just, like, sometimes there's ghosts. And, I never thought that it was a scary thing. Obviously, since then I've had many scary ghost experiences, butbeing raised in that environment it just really piquedmy curiosity and that never went away.
Surprisingly, for someone who has experienced so many hauntings, Bruni does not proclaim dogmatic belief.
From my interaction with what I believe could be spirits, I do think that they are some bit of us that's left behind after we pass, she said. I do think that classic idea of 'unfinished business' sometimes holds a piece of someone's consciousness here. That is my best guess, but I will never claim to say that that's absolutely what a ghost is.
And you never know if it's going to be explained one day, with quantum physics or other possibilities. The more that we do this and the more kind of strange experiments we do, the more questions we have. And so that's why I make a really big point in the book to never speak in absolutes.
Historical research of the homes, institutions and other places Bruni investigates and of the deceased people who lived in them and the people alive today who occupy these spaces is a critical element of her work.
History is a huge part of what we do, Bruni said. I can sit all day and try to prove the existence of ghosts. And people can be skeptical about it or not. But I will absolutely make sure my history is right. That is one thing that I can prove and I can get records of.
Bruni broke into the national spotlight during her time, from 2008 to 2014, as a star on Ghost Hunters, investigating cases for episodes including Dead Presidents, Family Plot, Nine Mens Misery and An Officer and an Apparition.
Kindred Spirits launched in 2016 and among the most-watched episodes are Ghost Train, set on Cape Cod; Hell House, about the Burrillville home; Fire Starter, which also happens to be the title of a Stephen King novel; Keeper of the Light, filmed on Rose Island, off Newport; and The Legacy of Lizzie Borden, taped in Fall River. Bruni has served as executive producer of all episodes of Kindred Spirits, which remains in production.
Bruni said the well-being of the inhabitants of a haunted house are a critical concern for her and her Kindred Spirits co-hosts, Adam Berry and Chip Coffey.
Some of these families have been dealing with this paranormal activity for years, and they've either been too afraid to say something or they feel like people don't believe them, Bruni said. We've actually encountered people who have legitimate PTSD from some of their experiences. And anxiety issues. Its so much more than just my house is haunted.
And there are so many people with stories than fans of horror movies orKing novels.
I meet people who don't even believe in ghosts, but they'll say but there was this one time and then they'll tell me this really crazy story. I think people feel comfortable talking to me about it. And you know, I live in one of the most haunted places in the country, in New England. And everyone's got a great ghost story here.
Story in the Public Square broadcasts each week on public television stations across the United States. In Rhode Island and southeastern New England, the show is broadcast on Rhode Island PBS on Sundays at 11 a.m. and is rebroadcast Thursdays at 7:30 p.m. An audio version of the program airs Saturdays at 8:30 a.m. & 6:30 p.m. ET, Sundays at 3:30 a.m. & 11:30 p.m. ET on SiriusXMs popular P.O.T.U.S. (Politics of the United States), channel 124. Story in the Public Square is a partnership between the Pell Center at Salve Regina Universityand The Providence Journal/USA TODAY Network.
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Quantum Theory Proposes That Cause and Effect Can Go In Loops – Universe Today
Causality is one of those difficult scientific topics that can easily stray into the realm of philosophy. Sciences relationship with the concept started out simply enough: an event causes another event later in time. That had been the standard understanding of the scientific community up until quantum mechanics was introduced. Then, with the introduction of the famous spooky action at a distance that is a side effect of the concept of quantum entanglement, scientists began to question that simple interpretation of causality.
Now, researchers at the Universit Libre de Bruxelles (ULB) and the University of Oxford have come up with a theory that further challenges that standard view of causality as a linear progress from cause to effect. In their new theoretical structure, cause and effect can sometimes take place in cycles, with the effect actually causing the cause.
The quantum realm itself as it is currently understood is inherently messy. There is no true understanding of things at that scale, which can be thought of better as a set of mathematical probabilities rather than actualities. These probabilities do not exactly lend themselves well to the idea of a definite cause and effect interaction between events either.
The researchers further muddied the waters using a tool known as a unitary transformation. Simply put, a unitary transformation is a fudge used to solve some of the math that is necessary to understand complex quantum systems. Using it makes solving the famous Schrodinger equation achievable using real computers.
To give a more complete explanation requires delving a bit into the space that quantum mechanics operates in. In quantum mechanics, time is simply another dimension that must be accounted for similarly to how the usual three dimensions of what we think of as linear space are accounted for. Physicists usually use another mathematical tool called a Hamiltonian to solve Schrodingers equation.
A Hamiltonian, though a mathematical concept, is often time dependent. However, it is also the part of the equation that is changed when a unitary transformation is introduced. As part of that action, it is possible to eliminate the time dependency of the Hamiltonian, to make it such that, instead of requiring time to go a certain direction (i.e. for action and reaction to take place linearly), the model turns more into a circle than a straight line, with action causing reaction and reaction causing action.
If this isnt all confusing enough, there are some extremely difficult to conceive of implications of this model (and to be clear, from a macro level, it is just a model). One important facet is that this finding has little to no relevance to every day cause and effect. The causes and effects that would be cyclical in this framework are not local in spacetime, according to the press release from ULB, so they are unlikely to have any impact on day to day life.
Even if it doesnt have any everyday impact now, this framework could hint at a combined theory of quantum mechanics and general relativity that has been the most sought after prize in physics for decades. If that synthesis is ever fully realized, there will be more implications for everyday life than just the existential questions of whether we are actually in control of our own actions or not.
Learn More:Eureka Alert: Quantum Causal LoopsNature Communications: Cyclic Quantum Causal ModelsFlorida News Times: Quantum Causal LoopUT: The three-body problem shows us why we cant accurately calculate the past
Lead Image:Artist depiction of quantum causal loopsCredit: ULB
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Quantum Theory Proposes That Cause and Effect Can Go In Loops - Universe Today