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Archive for the ‘quantum physics’ category: Page 227

Nov 9, 2022

The Spaceship Propulsion Compendium

Posted by in categories: mathematics, quantum physics, space travel

An in-depth survey of the various technologies for spaceship propulsion, both from those we can expect to see in a few years and those at the edge of theoretical science. We’ll break them down to basics and familiarize ourselves with the concepts.
Note: I made a rather large math error about the Force per Power the EmDrive exerts at 32:10, initial tentative results for thrust are a good deal higher than I calculated compared to a flashlight.

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Nov 8, 2022

100 Times Longer Than Previous Benchmarks — A Quantum Breakthrough

Posted by in categories: computing, quantum physics

On these timescales, a blink of an eye — one-tenth of a second — seems like eternity.

Researchers from the University of New South Wales have now broken new ground in demonstrating that ‘spin qubits,’ which are the fundamental informational units of quantum computers, can store data for up to two milliseconds. The accomplishment is 100 times longer than prior benchmarks in the same quantum processor for what is known as “coherence time,” the amount of time qubits can be manipulated in increasingly complicated calculations.

Nov 8, 2022

Quantum materials enable next-generation photonics and mobile networks in the terahertz regime

Posted by in categories: quantum physics, security

Terahertz light, radiation in the far-infrared part of the emission spectrum, is currently not fully exploited in technology, although it shows great potential for many applications in sensing, homeland security screening, and future (sixth generation) mobile networks.

Indeed, this radiation is harmless due to its small photon energy, but it can penetrate many materials (such as skin, packaging, etc.). In the last decade, a number of research groups have focused their attention on identifying techniques and materials to efficiently generate THz electromagnetic waves: among them is the wonder material graphene, which, however, does not provide the desired results. In particular, the generated terahertz output power is limited.

Better performance has now been achieved by topological insulators (TIs)—quantum materials that behave as insulators in the bulk while exhibiting conductive properties on the surface—according to a paper recently published in Light: Science & Applications.

Nov 8, 2022

A room-temperature polarization-sensitive CMOS terahertz camera based on quantum-dot-enhanced terahertz-to-visible photon upconversion

Posted by in categories: electronics, quantum physics

A terahertz camera based on an upconversion mechanism to the visible range can image both THz polarization state and field strength.

Nov 8, 2022

A Bold Solution To a Quantum Mystery: Does a “Game” Between Observer and Nature Define Existence?

Posted by in categories: entertainment, particle physics, quantum physics

A team of scientists from the University of Sciences and Technology of China has proposed a bold solution for the “measurement problem” in quantum mechanics, suggesting the eventual outcome for states of existence is determined by a “game” between the observer and nature.

For over a century, the quantum realm has imposed an abundance of bizarre obstacles along the road to understanding universal existence.

In the microscopic world of atoms and subatomic particles, nature demonstrates unparalleled strangeness, becoming unpredictable and operating in contrast to how it behaves at the macroscopic scale defined by classical physics.

Nov 7, 2022

Quantum Cryptography Is Unbreakable. So Is Human Ingenuity

Posted by in categories: business, computing, encryption, government, internet, mathematics, privacy, quantum physics, security

face_with_colon_three circa 2016.


Two basic types of encryption schemes are used on the internet today. One, known as symmetric-key cryptography, follows the same pattern that people have been using to send secret messages for thousands of years. If Alice wants to send Bob a secret message, they start by getting together somewhere they can’t be overheard and agree on a secret key; later, when they are separated, they can use this key to send messages that Eve the eavesdropper can’t understand even if she overhears them. This is the sort of encryption used when you set up an online account with your neighborhood bank; you and your bank already know private information about each other, and use that information to set up a secret password to protect your messages.

The second scheme is called public-key cryptography, and it was invented only in the 1970s. As the name suggests, these are systems where Alice and Bob agree on their key, or part of it, by exchanging only public information. This is incredibly useful in modern electronic commerce: if you want to send your credit card number safely over the internet to Amazon, for instance, you don’t want to have to drive to their headquarters to have a secret meeting first. Public-key systems rely on the fact that some mathematical processes seem to be easy to do, but difficult to undo. For example, for Alice to take two large whole numbers and multiply them is relatively easy; for Eve to take the result and recover the original numbers seems much harder.

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Nov 7, 2022

Quantum engineers improved the silicon chip performance by 100 times setting a new standard

Posted by in categories: computing, quantum physics

Their quantum computing processors can store information up to two milliseconds.

Researchers from the University of New South Wales have broken new ground in quantum computing by demonstrating that ‘spin qubits’- qubits where the information is stored in the spin momentum of an electron-can store data for up to two milliseconds, 100 times longer than previous benchmarks in the same quantum processor.

Classical computers work with bits—consisting of ones and zeroes—but a quantum computer uses quantum bits or qubits, which, on top of the ones and zeroes, also has a superposition where it can be a one and a zero at the same time.

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Nov 7, 2022

Scientists Suggest Our Brains Work Like Quantum Computers

Posted by in categories: computing, neuroscience, quantum physics

A study conducted by scientists from Trinity College Dublin could suggest that quantum processes are involved in the functions of our brains.

Nov 6, 2022

Quantum Error Correction Will Enable Quantum Telescopes

Posted by in categories: cosmology, quantum physics

Researchers from Australia and Singapore are working on a new quantum technique that could enhance optical VLBI. It’s known as Stimulated Raman Adiabatic Passage (STIRAP), which allows quantum information to be transferred without losses. When imprinted into a quantum error correction code, this technique could allow for VLBI observations into previously inaccessible wavelengths. Once integrated with next-generation instruments, this technique could allow for more detailed studies of black holes, exoplanets, the Solar System, and the surfaces of distant stars.

The interferometry technique consists of combining light from multiple telescopes to create images of an object that would otherwise be too difficult to resolve. Very Long Baseline Interferometry refers to a specific technique used in radio astronomy where signals from an astronomical radio source (black holes, quasars, pulsars, star-forming nebulae, etc.) are combined to create detailed images of their structure and activity. In recent years, VLBI has yielded the most detailed images of the stars that orbit Sagitarrius A* (Sgr A, the SMBH at the center of our galaxy.

Nov 6, 2022

Researchers From MIT Have Developed A New Machine Learning Based Approach With 90 Percent Accuracy To Screen Candidate Materials If They Are Topological For Next-Generation Computer Chips or Quantum Devices

Posted by in categories: biological, chemistry, quantum physics, robotics/AI

Topological materials are a special kind of material that have different functional properties on their surfaces than on their interiors. One of these properties is electrical. These materials have the potential to make electronic and optical devices much more efficient or serve as key components of quantum computers. But recent theories and calculations have shown that there can be thousands of compounds that have topological properties, and testing all of them to determine their topological properties through experiments will take years of work and analysis. Hence, there is a dire need for faster methods to test and study topological materials.

A team of researchers from MIT, Harvard University, Princeton University, and Argonne National Laboratory proposed a new approach that is faster at screening the candidate materials and can predict with more than 90 percent accuracy whether a material is topological or not. The traditional way of solving this problem is quite complicated and can be explained as follows: Firstly, a method called density functional theory is used to perform initial calculations, which are then followed by complex experiments that involve cutting a piece of material to atomic-level flatness and probing it with instruments under high vacuum.

The new proposed method is based on how the material absorbs X-rays, which is different from the old methods, which were based on photoemissions or tunneling electrons. There are certain significant advantages to using X-ray absorption data, which can be listed as follows: Firstly, there is no requirement for expensive lab apparatus. X-ray absorption spectrometers are used, which are readily available and can work in a typical environment, hence the low cost of setting up an experiment. Secondly, such measurements have already been done in chemistry and biology for other applications, so the data is already available for numerous materials.