STEM

[pollo]

http://climateerinvest.blogspot.com/2021/07/forget-5g-6g-is-coming-and-it-could.html

"Forget 5G: 6G Is Coming (And It Could Change Our World Forever)"

The fifth generation of mobile phones and data networks, better known as 5G, gained widespread adoption in 2020. But talk soon began of what we can expect from the next generation after that, 6G.

In late 2020  ATIS—the Alliance for Telecommunications Industry Solutions, added several members to its “Next G Alliance,” which it described at the time as “an initiative that will advance North American mobile technology leadership in 6G and beyond over the next decade, while building on the long-term evolution of 5G.”

Those members, who met last year, included Apple, Google, Intel, Hewlett Packard Enterprise, Charter, Cisco, Keysight Technologies, LG Electronics, Mavenir, MITRE and VMware. They joined existing members AT&T, Bell Canada, Ciena, Ericsson, Facebook, InterDigital, JMA Wireless, Microsoft, Nokia, Qualcomm Technologies Inc., Samsung, T-Mobile, TELUS, Telnyx, UScellular and Verizon.

That report indicated that 6G is unlikely to roll out until the 2030s.

Now, another new report is exploring what 6G might look like. At the recent (virtual) Mobile World Congress, Qualcomm’s leading 5G researcher Tingfang Ji talked about how both “5G Advanced,” as well as its future successor 6G, might look.

As is usually the case with new generations, 6G will likely require new bands of spectrum, with “terahertz spectrum” likely coming into play when it’s time for 6G. Terahertz is 1,000 times faster than gigahertz....

En vez de farolas tendrán que poner antenas y miniaturizar aún más pequeños reactores nucleares para alimentar a éstas y a los dispositivos móviles.

Yo sigo intentando ver qué puede revolucionar un cambio incremental en algo que ya existe. Pero bueno, el mundo de la "tecnología" lleva viviendo en estas ridículas hipérboles un par de décadas.

[Cadavre Exquis]

In a First, Scientists Have Connected a Superconductor To a Semiconductor
Posted by EditorDavid on Sunday July 11, 2021 @02:57PM from the current-events dept.

Long-time Slashdot reader schwit1 shares new from SciTechDaily:

For the first time, University of Basel researchers have equipped an ultrathin semiconductor with superconducting contacts. These extremely thin materials with novel electronic and optical properties could pave the way for previously unimagined applications. Combined with superconductors, they are expected to give rise to new quantum phenomena and find use in quantum technology....

With a view to future applications in electronics and quantum technology, researchers are focusing on the development of new components that consist of a single layer (monolayer) of a semiconducting material. Some naturally occurring materials with semiconducting properties feature monolayers of this kind, stacked to form a three-dimensional crystal. In the laboratory, researchers can separate these layers — which are no thicker than a single molecule — and use them to build electronic components. These ultrathin semiconductors promise to deliver unique characteristics that are otherwise very difficult to control, such as the use of electric fields to influence the magnetic moments of the electrons. In addition, complex quantum mechanical phenomena take place in these semiconducting monolayers that may have applications in quantum technology...

A team of physicists, led by Dr. Andreas Baumgartner in the research group of Professor Christian Schönenberger at the Swiss Nanoscience Institute and the Department of Physics of the University of Basel, has now fitted a monolayer of the semiconductor molybdenum disulfide with superconducting contacts for the first time...

"In a superconductor, the electrons arrange themselves into pairs, like partners in a dance — with weird and wonderful consequences, such as the flow of the electrical current without a resistance," explains Baumgartner, the project manager of the study. "In the semiconductor molybdenum disulfide, on the other hand, the electrons perform a completely different dance, a strange solo routine that also incorporates their magnetic moments. Now we would like to find out which new and exotic dances the electrons agree upon if we combine these materials."

Mehdi Ramezani, lead author of the study, says that "In principle, the vertical contacts we've developed for the semiconductor layers can be applied to a large number of semiconductors."

Saludos.

[Cadavre Exquis]

El 15 de julio Demis Hassabis publico un tweet en el anunciaba tanto la publicación en Nature de los resultados de AlphaFold2 (que ya el año pasado sorprendió a todos los expertos que llevan décadas trabajando en el problema del plegado de proteínas puesto que el nuevo algoritmo desarrollado por DeepMind hacía palidecer a los mejores algoritmos existentes hasta el momento) como la liberación del código fuente del proyecto.

https://twitter.com/demishassabis/status/1415736975395631111

Hoy se ha desvelado lo que se escondía tras la última frase del tweet ("More very soon!") y, ciertamente, ha vuelto a asombrar a propios y extraños ya que han liberado una BB.DD. que contiene la información sobre el plegado de la práctica totalidad de las 20.000 proteínas que expresa el genoma humano  .

AI Firm DeepMind Puts Database of the Building Blocks of Life Online
Posted by msmash on Thursday July 22, 2021 @12:05PM from the closer-look dept.

Last year the artificial intelligence group DeepMind cracked a mystery that has flummoxed scientists for decades: stripping bare the structure of proteins, the building blocks of life. Now, having amassed a database of nearly all human protein structures, the company is making the resource available online free for researchers to use. From a report:

The key to understanding our basic biological machinery is its architecture. The chains of amino acids that comprise proteins twist and turn to make the most confounding of 3D shapes. It is this elaborate form that explains protein function; from enzymes that are crucial to metabolism to antibodies that fight infectious attacks. Despite years of onerous and expensive lab work that began in the 1950s, scientists have only decoded the structure of a fraction of human proteins.

DeepMind's AI program, AlphaFold, has predicted the structure of nearly all 20,000 proteins expressed by humans. In an independent benchmark test that compared predictions to known structures, the system was able to predict the shape of a protein to a good standard 95% of time. DeepMind, which has partnered with the European Molecular Biology Laboratory's European Bioinformatics Institute (EMBL-EBI), hopes the database will help researchers to analyse how life works at an atomic scale by unpacking the apparatus that drives some diseases, make strides in the field of personalised medicine, create more nutritious crops and develop "green enzymes" that can break down plastic.

No es ninguna exageración el afirmar que es un avance tanto o más importante que el que supuso la secuenciación del genoma humano hace algo más de dos décadas.

Saludos.

[Cadavre Exquis]

Startup Claims Breakthrough in Long-Duration Batteries
Posted by msmash on Friday July 23, 2021 @04:01PM from the how-about-that dept.

A four-year-old startup says it has built an inexpensive battery that can discharge power for days using one of the most common elements on Earth: iron. From a report:

Form Energy's batteries are far too heavy for electric cars. But it says they will be capable of solving one of the most elusive problems facing renewable energy: cheaply storing large amounts of electricity to power grids when the sun isn't shining and wind isn't blowing. The work of the Somerville, Mass., company has long been shrouded in secrecy and nondisclosure agreements. It recently shared its progress with The Wall Street Journal, saying it wants to make regulators and utilities aware that if all continues to go according to plan, its iron-air batteries will be capable of affordable, long-duration power storage by 2025.

Its backers include Breakthrough Energy Ventures, a climate investment fund whose investors include Microsoft co-founder Bill Gates and Amazon founder Jeff Bezos. Form recently initiated a $200 million funding round, led by a strategic investment from steelmaking giant ArcelorMittal one of the world's leading iron-ore producers. Form is preparing to soon be in production of the "kind of battery you need to fully retire thermal assets like coal and natural gas" power plants, said the company's chief executive, Mateo Jaramillo, who developed Tesla's Powerwall battery and worked on some of its earliest automotive powertrains. On a recent tour of Form's windowless laboratory, Mr. Jaramillo gestured to barrels filled with low-cost iron pellets as its key advantage in the rapidly evolving battery space. Its prototype battery, nicknamed Big Jim, is filled with 18,000 pebble-size gray pieces of iron, an abundant, nontoxic and nonflammable mineral.

For a lithium-ion battery cell, the workhorse of electric vehicles and today's grid-scale batteries, the nickel, cobalt, lithium and manganese minerals used currently cost between $50 and $80 per kilowatt-hour of storage, according to analysts. Using iron, Form believes it will spend less than $6 per kilowatt-hour of storage on materials for each cell. Packaging the cells together into a full battery system will raise the price to less than $20 per kilowatt-hour, a level at which academics have said renewables plus storage could fully replace traditional fossil-fuel-burning power plants. A battery capable of cheaply discharging power for days has been a holy grail in the energy industry, due to the problem that it solves and the potential market it creates.

Comunicado de prensa de ayer de ArcelorMittal:

ArcelorMittal invierte 25 millones de dólares (USD) en Form Energy

El acuerdo suscrito representa la segunda inversión realizada a través del Fondo para la Innovación XCarb™ de ArcelorMittal.

ArcelorMittal (“la Sociedad”) anuncia hoy que ha llevado cabo la segunda inversión a través de su recientemente creado Fondo para la Innovación XCarb™, posicionándose como inversor principal en la ronda de financiación de Serie D por valor de 200 millones de dólares (USD) de Form Energy, con una inyección de capital de 25 millones de dólares (USD).

Form Energy, empresa fundada en 2017, está enfocando sus esfuerzos a acelerar el desarrollo de su innovadora tecnología de almacenamiento de energía de bajo coste para permitir el establecimiento de una red eléctrica fiable, segura y alimentada exclusivamente con energía renovable, durante todo el año. La empresa presentó recientemente una nueva batería de hierro-aire que reúne las siguientes características: bajo coste (aproximadamente una décima parte del coste de la tecnología de las baterías de iones de litio); varios días de duración (una duración de 100 horas, lo que permite superar el problema derivado de la naturaleza intermitente de la generación de energía renovable); ampliable e instalable en cualquier lugar.

Paralelamente a la inversión de 25 millones de dólares (USD), ArcelorMittal y Form Energy han suscrito un acuerdo de desarrollo conjunto para explorar la posibilidad de que ArcelorMittal suministre hierro, adaptado a requisitos específicos, a Form Energy como carga férrica para las baterías basadas en su tecnología.

Greg Ludkovsky, responsable de la organización de Investigación y Desarrollo de ArcelorMittal a escala mundial, declaró:

“Form Energy se sitúa a la vanguardia en los desarrollos de sistemas de almacenamiento de energía en baterías, a escala de la red eléctrica y de larga duración. La tecnología que han desarrollado, que permite el almacenamiento de energía durante varios días, ofrece un enorme potencial de cara a superar el problema de la intermitencia del suministro de energía renovable. Son exactamente la clase de empresa ambiciosa e innovadora en la que queremos invertir a través de nuestro Fondo para la Innovación XCarb™.

Además de nuestra inversión, existen evidentes sinergias que estamos explorando con ellos. Estas sinergias incluyen desde el suministro por parte de ArcelorMittal de hierro para las soluciones utilizadas en sus baterías, hasta el potencial que ofrecen sus baterías para proporcionarnos un suministro permanente y fiable de energía generada a partir de fuentes renovables para nuestras plantas siderúrgicas, ayudándonos por lo tanto en nuestro proceso de transición hacia una producción siderúrgica neutra en carbono”.

Mateo Jaramillo, CEO y cofundador de Form Energy, añadió:

“Son tiempos apasionantes para Form Energy y nos entusiasma la incorporación de ArcelorMittal como socio empresarial e inversor.

ArcelorMittal es el principal productor siderúrgico y minero a escala mundial y esta inversión demuestra su compromiso con la innovación y la descarbonización profunda. Agradecemos su confianza en nuestro equipo humano y en nuestra tecnología, en la que estamos trabajando con el objetivo de rediseñar el sistema eléctrico global y permitir un futuro con energía limpia".

La inversión es la segunda realizada por ArcelorMittal a través de su Fondo para la Innovación XCarb™, creado en marzo de 2021. La primera fue una inversión inicial de 10 millones de dólares (USD) en Heliogen, una empresa de tecnología vinculada a las energías renovables cuyo objetivo se centra en “liberar la energía solar para sustituir a los combustibles fósiles”, realizada el pasado 8 de junio.

El Fondo para la Innovación XCarb™ – en el que ArcelorMittal prevé invertir anualmente hasta 100 millones de dólares (USD) – está diseñado para inversiones en empresas dedicadas al desarrollo de tecnologías que ofrecen el potencial de apoyar y acelerar la transición hacia una producción siderúrgica neutra en carbono. El Fondo fue creado por ArcelorMittal en el marco de su iniciativa XCarb™, la cual englobará en el futuro todos los esfuerzos realizados por la Empresa para avanzar hacia la neutralidad en carbono.



El presente documento es una traducción al español, a efectos meramente orientativos, del comunicado de prensa original en inglés y publicado en la página web de la Sociedad http://corporate.arcelormittal.com/. En caso de discrepancia entre ambos documentos, prevalecerá el texto original en inglés.

Saludos.

[Saturio]

Esperemos que sea cierto y no que, simplemente, Acerlor Mittal haya decidido diversificar su negocio con una línea de "dar el pase de startups".

[Cadavre Exquis]

Aunque hacía ya tiempo que se había conseguido crear imanes bidimensionales, hasta ahora no se había logrado que fuesen estables a temperatura ambiente. Lo relevante de este avance es haber logrado este tipo de imanes y que mantengan sus propiedades no solo a temperatura ambiente sino incluso temperaturas de hasta 100º C.

Según sus descubridores, no ven ningún obstáculo que impidiera el poder fabricarlo de forma masiva y a bajo coste lo cual, evidentemente, allana el camino a posibles usos industriales del mismo, siendo quizás su uso más evidente —al menos, en el campo de la informática—, el de la creación de nuevos tipos de memoria con una mayor densidad de almacenamiento de la información.

Scientists create world's thinnest magnet
by Lawrence Berkeley National Laboratory | July 20, 2021

Illustration of magnetic coupling in a cobalt-doped zinc-oxide monolayer. Red, blue, and yellow spheres represent cobalt, oxygen, and zinc atoms, respectively. Credit: Berkeley Lab

The development of an ultrathin magnet that operates at room temperature could lead to new applications in computing and electronics—such as high-density, compact spintronic memory devices—and new tools for the study of quantum physics.

The ultrathin magnet, which was recently reported in the journal Nature Communications , could make big advances in next-gen memories, computing, spintronics, and quantum physics. It was discovered by scientists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley.

"We're the first to make a room-temperature 2-D magnet that is chemically stable under ambient conditions," said senior author Jie Yao, a faculty scientist in Berkeley Lab's Materials Sciences Division and associate professor of materials science and engineering at UC Berkeley.

"This discovery is exciting because it not only makes 2-D magnetism possible at room temperature, but it also uncovers a new mechanism to realize 2-D magnetic materials," added Rui Chen, a UC Berkeley graduate student in the Yao Research Group and lead author on the study.

The magnetic component of today's memory devices is typically made of magnetic thin films. But at the atomic level, these magnetic films are still three-dimensional—hundreds or thousands of atoms thick. For decades, researchers have searched for ways to make thinner and smaller 2-D magnets and thus enable data to be stored at a much higher density.

Previous achievements in the field of 2-D magnetic materials have brought promising results. But these early 2-D magnets lose their magnetism and become chemically unstable at room temperature.

"State-of-the-art 2-D magnets need very low temperatures to function. But for practical reasons, a data center needs to run at room temperature," Yao said. "Theoretically, we know that the smaller the magnet, the larger the disc's potential data density. Our 2-D magnet is not only the first that operates at room temperature or higher, but it is also the first magnet to reach the true 2-D limit: It's as thin as a single atom!"

The researchers say that their discovery will also enable new opportunities to study quantum physics. "Our atomically thin magnet offers an optimal platform for probing the quantum world," Yao said. "It opens up every single atom for examination, which may reveal how quantum physics governs each single magnetic atom and the interactions between them. With a conventional bulk magnet where most of the magnetic atoms are deeply buried inside the material, such studies would be quite challenging to do."

The making of a 2-D magnet that can take the heat

The researchers synthesized the new 2-D magnet—called a cobalt-doped van der Waals zinc-oxide magnet—from a solution of graphene oxide, zinc, and cobalt. Just a few hours of baking in a conventional lab oven transformed the mixture into a single atomic layer of zinc-oxide with a smattering of cobalt atoms sandwiched between layers of graphene. In a final step, graphene is burned away, leaving behind just a single atomic layer of cobalt-doped zinc-oxide.

"With our material, there are no major obstacles for industry to adopt our solution-based method," said Yao. "It's potentially scalable for mass production at lower costs."

To confirm that the resulting 2-D film is just one atom thick, Yao and his team conducted scanning electron microscopy experiments at Berkeley Lab's Molecular Foundry to identify the material's morphology, and transmission electron microscopy imaging to probe the material atom by atom.

With proof in hand that their 2-D material really is just an atom thick, the researchers went on to the next challenge that had confounded researchers for years: Demonstrating a 2-D magnet that successfully operates at room temperature.

X-ray experiments at Berkeley Lab's Advanced Light Source characterized the 2-D material's magnetic parameters under high temperature. Additional X-ray experiments at SLAC National Accelerator Laboratory's Stanford Synchrotron Radiation Lightsource verified the electronic and crystal structures of the synthesized 2-D magnets. And at Argonne National Laboratory's Center for Nanoscale Materials, the researchers imaged the 2-D material's crystal structure and chemical composition using transmission electron microscopy.

As a whole, the research team's lab experiments showed that the graphene-zinc-oxide system becomes weakly magnetic with a 5-6% concentration of cobalt atoms. Increasing the concentration of cobalt atoms to about 12% results in a very strong magnet.

To the researchers' surprise, a concentration of cobalt atoms exceeding 15% shifts the 2-D magnet into an exotic quantum state of "frustration," whereby different magnetic states within the 2-D system are in competition with each other.

And unlike previous 2-D magnets, which lose their magnetism at room temperature or above, the researchers found that the new 2-D magnet not only works at room temperature but also at 100 degrees Celsius (212 degrees Fahrenheit).

"Our 2-D magnetic system shows a distinct mechanism compared to previous 2-D magnets," said Chen. "And we think this unique mechanism is due to the free electrons in zinc oxide."

True north: Free electrons keep magnetic atoms on track

When you command your computer to save a file, that information is stored as a series of ones and zeroes in the computer's magnetic memory, such as the magnetic hard drive or a flash memory. And like all magnets, magnetic memory devices contain microscopic magnets with two poles—north and south, the orientations of which follow the direction of an external magnetic field. Data is written or encoded when these tiny magnets are flipped to the desired directions.

According to Chen, zinc oxide's free electrons could act as an intermediary that ensures the magnetic cobalt atoms in the new 2-D device continue pointing in the same direction—and thus stay magnetic—even when the host, in this case the semiconductor zinc oxide, is a nonmagnetic material.

"Free electrons are constituents of electric currents. They move in the same direction to conduct electricity," Yao added, comparing the movement of free electrons in metals and semiconductors to the flow of water molecules in a stream of water.

The researchers say that new material—which can be bent into almost any shape without breaking, and is 1 millionth the thickness of a single sheet of paper—could help advance the application of spin electronics or spintronics, a new technology that uses the orientation of an electron's spin rather than its charge to encode data. "Our 2-D magnet may enable the formation of ultra-compact spintronic devices to engineer the spins of the electrons," Chen said.

"I believe that the discovery of this new, robust, truly two-dimensional magnet at room temperature is a genuine breakthrough by Jie Yao and his students," said co-author Robert Birgeneau, a faculty senior scientist in Berkeley Lab's Materials Sciences Division and professor of physics at UC Berkeley who co-led the study's magnetic measurements. "In addition to its obvious significance to spintronic devices, this 2-D magnet is fascinating at the atomic level, revealing for the first time how cobalt magnetic atoms interact over 'long' distances" through a complex two-dimensional network, he added.

"Our results are even better than what we expected, which is really exciting. Most of the time in science, experiments can be very challenging," he said. "But when you finally realize something new, it's always very fulfilling."

Saludos.

[saturno]

Si es cierto lo del magnetismo en 2D, y encima fabricando el imán en un horno común de laboratorio, también me digo que Corea/Taiwan pero sobre todo a China/India se pondrán ya mismo a diseñar las máquinas.

Entiendo que la patente aquí no pesa nada, lo determinante va a ser el diseño de máquinas para fabricar discos donde quepan los servidores de Amazon o de Google en un par de unidades como las de ahora.
Qué digo, ¿dos discos duros ? Uno para datos, y el otro para respaldo

La explicación sobre el comportamiento cuántico de los electrones no lo he entendido.
¿tiene que ver con la operación de lectura/escritura?
Ver Spintronics

En 2 o 3 años, veremos las primeras unidades. El parque mundial de PC y smartphones obsoleto en 5 años (supongo que habrá que cambiar los chips controladores de la placa base por otros que sean "cuánticos")

[Cadavre Exquis]

La explicación sobre el comportamiento cuántico de los electrones no lo he entendido.
¿tiene que ver con la operación de lectura/escritura?
Ver Spintronics

Para responder a esa pregunta creo que lo más fácil es traer a colación la famosa "ley de Moore" y poner en duda el que, como se ha venido anunciando, esté "muerta":

Se tiende a asumir que la ley de Moore dejará de cumplirse en el momento en el que las técnicas actuales de fabricación de semiconductores basados en técnicas como la litografía ultravioleta extrema no den más de si (si vieron el vídeo que traje en un post anterior sobre la fabricación actual de circuitos integrados utilizando EUV sabrán que la tecnología para realizarla es casi de ciencia ficción ya que en este momento no es posible crear lasers que emitan fotones directamente en el ultravioleta extremo y hay que usar el "truco" de excitar los electones de los átomos de esferas microscópicas de estaño que, al decaer, emiten fotones en esa frecuencia del ulravioleta extremo con el que se irradian las máscaras que permiten producir los circuitos integrados con transistores de unos pocos nanómetros).

Pero la realidad es que, igual que se pasó de las tarjetas perforadas a los relés, y de ahí a las válvulas de vacío y más tarde al transistor, hay vida después del circuito integrado tal y como lo conocemos actualmente, y los avances que se están produciendo en fotónica y espintrónica permitirán superar las limitaciones que supone el tener que andar haciendo circular electrones en los transistores y nano-cables que los conectan pues la pérdida energética que ello conlleva que se manifiesta principalmente en forma de calor ha sido y sigue suponiendo uno de los principales problemas que tenemos a la hora de crear procesadores más rápidos y eficientes.

Fotónica

La fotónica ha sido un desarrollo crucial en el ámbito de las telecomunicaciones permitiendo crear dispositivos como los switches ópticos capaces de realizar el enrutado de tráfico entre fibras ópticas sin tener que transformar la señal que viene en forma fotones mediante un foto transistor en electrones para poder procesarla y luego volver a transformarla en fotones mediante un diodo laser una vez decidido el camino que tiene que seguir la señal lo cual es no solo mucho más eficiente sino, sobre todo, mucho más rápido.

The overhead view of a new beamsplitter for silicon photonics chips that is the size of one-fiftieth the width of a human hair. Credit: Dan Hixson/University of Utah College of Engineering

Ya hace tiempo que se están empleando esos transistores ópticos en el desarrollo de circuitos integrados  mucho más eficientes que los actuales, no solo por el hecho de que los fotones puedan viajar más rápido que los electrones por un circuito integrado, sino, sobre todo, por lo que se refiere a la reducción de las pérdidas energéticas en forma de calor de las que hablábamos antes. Esto permitiría operar a los transistores ópticos a frecuencias que no son viables para los transistores tradicionales (vid. Más cerca de procesar datos a la velocidad de la luz).

Espintrónica

Aunque todavía es una tecnología incipiente, la espintrónica permitió un gran avance en lo que al almacenamiento de información se refiere al permitir la creación de la tecnología GMR (Giant Magnetoresistance Effect) en la fabricación de las cabezas de lectura/escritura de los discos duros ya en 1997.

Si les interesa el tema les recomiendo la web de  EsPinRed la "Red Española de Espintrónica" en la que pueden ver lo que se cuece en el mundillo en la actualidad. En este apartado de dicha web tienen un buen resumen de la relativamente corta historia de la espintrónica.

Saludos.

[Cadavre Exquis]

Como siempre, un interesante post de Francis Villatoro en relación con el ITER (lo anecdótico sería el titular, yo me quedaría con el último párrafo en el que se habla de DEMO y PROTO, los sucesores de ITER)

https://twitter.com/emulenews/status/1419361258680299522

Atención, pregunta: ¿El imán de ITER puede levantar un portaaviones dos metros en el aire?
Por Francisco R. Villatoro, el 25 julio, 2021.

Seguro que has leído alguna vez que «el imán más poderoso del mundo está en el ITER y es tan potente que puede levantar un portaaviones dos metros en el aire». ¿Crees que es posible? ¿Te atreves a repetir el cálculo? El imán citado es el solenoide central de ITER, con forma de cilindro de 18 metros de alto y 4.25 metros de diámetro, y 1000 toneladas de peso; está formado por seis bobinas individuales y contendrá 35.6 kilómetros de hilos superconductores de una aleación de estaño y niobio (Nb₃Sn). El campo magnético máximo en su centro será de 13.1 T (teslas), siendo el más potente de todo ITER. Su objetivo es inyectar una corriente eléctrica de 15 MA (megaamperios) en el plasma durante entre 300 y 500 segundos. Para ello almacenará una energía magnética de 6.4 GJ (gigajulios); los ingenieros de ITER afirman que esta energía sería suficiente para levantar un portaaviones unos dos metros. ¿Crees que es posible?

Repetir el cálculo energético parece sencillo. La energía necesaria para levantar un objeto de masa m a una altura h es igual a U = m g h, donde g es la aceleración de la gravedad; un portaaviones típico (Clase Nimitz) tiene una masa de ~ 100 000 toneladas​, luego se requiere una energía de ~ 2 GJ para levantarlo dos metros. ¿Se han equivocado los ingenieros al realizar su cálculo? Vayamos a la fuente. Hasta donde me consta, lo que dijo Neil Mitchell, jefe de la División de Imanes de ITER, es que las mitades superior e inferior del solenoide central se atraen la una a la otra con una fuerza equivalente a 50 000 toneladas («What happens to the car keys?» Naive question of the week, ITER Newsline, 12 Feb 2018). En sus propias palabras, «si se partiera por la mitad el solenide central de 18 metros de altura y si un portaaviones de 100 000 toneladas se situara sobre la parte inferior, el portaaviones se elevaría hasta cerrar el circuito» («if there was a gap in the middle of the 18-metre-high component, and if a 100,000-tonne aircraft-carrier was attached to the bottom, the carrier would indeed be lifted until the gap closed«).

Fuente: https://www.uv.es/martined/tecweb/Dipolos_magneticos.pdf

Seguro que te habrás dado cuenta de que es imposible que un portaaviones con una eslora de 333 m, una manga de 41 m y un calado (mínimo) de 12 m quepa en un hueco de dos metros entre dos solenoides de 4.25 m de diámetro. ¿Qué pasaría si se colocaran ambas mitades del solenoide central encima y debajo del portaaviones? No sé si sabrás que la fuerza magnética entre dos solenoides decae con la cuarta potencia de la distancia que los separas (aproximo los dos solenoides por dipolos magnéticos). Así resulta que la fuerza magnética sería insuficiente para levantar el portaaviones; la fuerza entre los dos solenoides separados una distancia de 12 metros (calado) sería 6⁴ = 1296 veces más pequeña que si están separados dos metros (y en rigor sería necesaria una distancia de 14 metros que haría la fuerza 7⁴ = 2401 veces más pequeña). De hecho, el artículo de ITER Newsline se pregunta ¿qué pasará con las llaves de los técnicos en la sala de control? Como está situada a unos 30 metros de distancia del solenoide central y la fuerza magnética decae con la distancia al cuadrado, las llaves de los técnicos estarán a salvo en sus bolsillos.

Por cierto, ITER (International Thermonuclear Experimental Reactor) es un reactor experimental de fusión en Cadarache, Francia; su construcción debería finalizar en diciembre de 2025 (momento en que se inyectará el primer plasma); estudiará la física de plasmas hasta 2035, cuando se inyectará deuterio y tritio para lograr la ignición de la fusión. El récord actual de fusión lo ostenta el tokamak JET, que logró en 1997 la producción de 16 MW a partir de una entrada de 24 MW (Q = 0.67). El objetivo de ITER es generar 500 MW a partir de 50 MW (Q = 10) usando 0.5 gramos de combustible. ITER no es capaz de generar energía eléctrica, siendo un primer paso para el futuro DEMO, que podrá hacerlo; finalmente, PROTO será un prototipo de reactor nuclear de fusión que los 35 países miembros de la colaboración ITER podrán replicar. El camino de ITER+DEMO+PROTO llevará a una solución al gran problema del siglo XXI, el problema de la energía; en mi opinión, en la segunda mitad del siglo XXI la energía de fusión dominará la producción de energía eléctrica en el mundo.

Saludos.

[dmar]

Como siempre, un interesante post de Francis Villatoro en relación con el ITER (lo anecdótico sería el titular, yo me quedaría con el último párrafo en el que se habla de DEMO y PROTO, los sucesores de ITER)

https://twitter.com/emulenews/status/1419361258680299522

Atención, pregunta: ¿El imán de ITER puede levantar un portaaviones dos metros en el aire?
Por Francisco R. Villatoro, el 25 julio, 2021.

Por cierto, ITER (International Thermonuclear Experimental Reactor) es un reactor experimental de fusión en Cadarache, Francia; su construcción debería finalizar en diciembre de 2025 (momento en que se inyectará el primer plasma); estudiará la física de plasmas hasta 2035, cuando se inyectará deuterio y tritio para lograr la ignición de la fusión. El récord actual de fusión lo ostenta el tokamak JET, que logró en 1997 la producción de 16 MW a partir de una entrada de 24 MW (Q = 0.67). El objetivo de ITER es generar 500 MW a partir de 50 MW (Q = 10) usando 0.5 gramos de combustible. ITER no es capaz de generar energía eléctrica, siendo un primer paso para el futuro DEMO, que podrá hacerlo; finalmente, PROTO será un prototipo de reactor nuclear de fusión que los 35 países miembros de la colaboración ITER podrán replicar. El camino de ITER+DEMO+PROTO llevará a una solución al gran problema del siglo XXI, el problema de la energía; en mi opinión, en la segunda mitad del siglo XXI la energía de fusión dominará la producción de energía eléctrica en el mundo.

Saludos.

Profundizando, leo que está previsto que la primera ignición de ITER con combustible de fisión sería en 2035 y que DEMO empiece a funcionar en 2051.

¿Y qué hacemos nosotros pretendiendo no comer carne en 2050 (medida de eficacia marginal y coste elevado) en vez de estar invirtiendo los fondos verdes en acelerar esos hitos?  ¿Qué se me está escapando?

[el malo]

Como siempre, un interesante post de Francis Villatoro en relación con el ITER (lo anecdótico sería el titular, yo me quedaría con el último párrafo en el que se habla de DEMO y PROTO, los sucesores de ITER)

https://twitter.com/emulenews/status/1419361258680299522

Atención, pregunta: ¿El imán de ITER puede levantar un portaaviones dos metros en el aire?
Por Francisco R. Villatoro, el 25 julio, 2021.

Por cierto, ITER (International Thermonuclear Experimental Reactor) es un reactor experimental de fusión en Cadarache, Francia; su construcción debería finalizar en diciembre de 2025 (momento en que se inyectará el primer plasma); estudiará la física de plasmas hasta 2035, cuando se inyectará deuterio y tritio para lograr la ignición de la fusión. El récord actual de fusión lo ostenta el tokamak JET, que logró en 1997 la producción de 16 MW a partir de una entrada de 24 MW (Q = 0.67). El objetivo de ITER es generar 500 MW a partir de 50 MW (Q = 10) usando 0.5 gramos de combustible. ITER no es capaz de generar energía eléctrica, siendo un primer paso para el futuro DEMO, que podrá hacerlo; finalmente, PROTO será un prototipo de reactor nuclear de fusión que los 35 países miembros de la colaboración ITER podrán replicar. El camino de ITER+DEMO+PROTO llevará a una solución al gran problema del siglo XXI, el problema de la energía; en mi opinión, en la segunda mitad del siglo XXI la energía de fusión dominará la producción de energía eléctrica en el mundo.

Saludos.

Profundizando, leo que está previsto que la primera ignición de ITER con combustible de fisión sería en 2035 y que DEMO empiece a funcionar en 2051.

¿Y qué hacemos nosotros pretendiendo no comer carne en 2050 (medida de eficacia marginal y coste elevado) en vez de estar invirtiendo los fondos verdes en acelerar esos hitos?  ¿Qué se me está escapando?

Mi profesor de Biología en BUP y COU nos puso este ejemplo de lo que pasó en su primer día en la Universidad.

Les pusieron unas diapositivas con unos activistas de Green Peace encadenados a unos árboles y otras de unos señores tomando muestras de agua de unos arroyos y análizándolas en el laboratorio. El profesor les preguntó: ¿quién creéis que hace más por el medio ambiente? ¿en cuál de los dos grupos está el verdadero ecologista?

Me acuerdo muchas veces de ese ejemplo.

Esto es igual. Por un lado tenemos a los científicos de verdad que son los que están trabajando por un mundo sostenible. Por otro a los cuatro ecolojetas de salón diciendo que el planeta se va a la mierda porque te comes un filete o has cogido el coche para ir a comprar. De Greta hablamos otro día.

Hace años le leí a PPCC que la siguiente gran burbuja sería la ecología. Hay mucho dinero en juego porque la ecología es un medio perfecto de control social. Decir a la gente que no puede conducir su propio coche queda muy feo y muy de Corea del Norte, pero decirles que no pueden conducirlo por el bien del planeta queda muy bien y hará que la gente no sólo deje el coche en casa sino que denuncien al vecino por coger el suyo. Nadie quiere quedarse sin planeta, ¿verdad? 

[Derby]

https://www.reuters.com/article/cerebras-tech/cerebras-systems-connects-its-huge-chips-to-make-ai-more-power-efficient-idUSL1N2PV24H

Cerebras Systems connects its huge chips to make AI more power-efficient

(Reuters) - Cerebras Systems, the Silicon Valley startup making the world’s largest computer chip, said on Tuesday it can now weave together almost 200 of the chips to drastically reduce the power consumed by artificial-intelligence work.

Cerebras is one of a number of startups making chips specifically designed for AI and aiming to challenge current market leaders Nvidia Corp and Alphabet Inc’s Google. The company has raised about $475 million in venture capital and has secured deals with pharmaceutical firms GlaxoSmithKline Plc and AstraZeneca Plc to use its chips to speed up drug discovery.

Traditionally, hundreds or even thousands of computer chips are manufactured on a 12-inch (30 cm) silicon disc called a wafer, which is later sliced up into individual chips. Cerebras, by contrast, uses the entire wafer. The huge Cerebras chip can hold more data at once.

But artificial intelligence researchers now have AI models called “neural networks” too big for any single chip to hold, so they must split them up across many chips. The biggest current neural networks are still only a fraction of the complexity of a human brain, but they use much more energy than human brains because the systems that run them become less power-efficient as more chips are added.

Cerebras said on Wednesday that it can put together 192 of its chips to train huge neural networks, but that the power efficiency will stay the same as chips are added. In other words, Cerebras can double the amount of computing its chips do for double the power, unlike current systems that need more than twice as much power to double their computing capacity.

Current AI systems “are in the realm where you’re talking about tens of megawatts of power, and you’re doing it over months. You’re using a the equivalent of a small city’s power to train these networks,” Cerebras Chief Executive Andrew Feldman told Reuters. “Power is extremely important.”

[Cadavre Exquis]

En relación con el chip de Cerebras vi esta entrada hace unos días en Slashdot:

What Does It Take to Build the World's Largest Computer Chip?
Posted by EditorDavid on Monday August 23, 2021 @03:34AM from the heavy-hardware dept.

The New Yorker looks at Cerebras, a startup which has raised nearly half a billion dollars to build massive plate-sized chips targeted at AI applications — the largest computer chip in the world.

In the end, said Cerebras's co-founder Andrew Feldman, the mega-chip design offers several advantages. Cores communicate faster when they're on the same chip: instead of being spread around a room, the computer's brain is now in a single skull. Big chips handle memory better, too. Typically, a small chip that's ready to process a file must first fetch it from a shared memory chip located elsewhere on its circuit board; only the most frequently used data might be cached closer to home...

A typical, large computer chip might draw three hundred and fifty watts of power, but Cerebras's giant chip draws fifteen kilowatts — enough to run a small house. "Nobody ever delivered that much power to a chip," Feldman said. "Nobody ever had to cool a chip like that." In the end, three-quarters of the CS-1, the computer that Cerebras built around its WSE-1 chip, is dedicated to preventing the motherboard from melting. Most computers use fans to blow cool air over their processors, but the CS-1 uses water, which conducts heat better; connected to piping and sitting atop the silicon is a water-cooled plate, made of a custom copper alloy that won't expand too much when warmed, and polished to perfection so as not to scratch the chip. On most chips, data and power flow in through wires at the edges, in roughly the same way that they arrive at a suburban house; for the more metropolitan Wafer-Scale Engines, they needed to come in perpendicularly, from below. The engineers had to invent a new connecting material that could withstand the heat and stress of the mega-chip environment. "That took us more than a year," Feldman said...

In a rack in a data center, it takes up the same space as fifteen of the pizza-box-size machines powered by G.P.U.s. Custom-built machine-learning software works to assign tasks to the chip in the most efficient way possible, and even distributes work in order to prevent cold spots, so that the wafer doesn't crack.... According to Cerebras, the CS-1 is being used in several world-class labs — including the Lawrence Livermore National Laboratory, the Pittsburgh Supercomputing Center, and E.P.C.C., the supercomputing centre at the University of Edinburgh — as well as by pharmaceutical companies, industrial firms, and "military and intelligence customers." Earlier this year, in a blog post, an engineer at the pharmaceutical company AstraZeneca wrote that it had used a CS-1 to train a neural network that could extract information from research papers; the computer performed in two days what would take "a large cluster of G.P.U.s" two weeks.

The U.S. National Energy Technology Laboratory reported that its CS-1 solved a system of equations more than two hundred times faster than its supercomputer, while using "a fraction" of the power consumption. "To our knowledge, this is the first ever system capable of faster-than real-time simulation of millions of cells in realistic fluid-dynamics models," the researchers wrote. They concluded that, because of scaling inefficiencies, there could be no version of their supercomputer big enough to beat the CS-1.... Bronis de Supinski, the C.T.O. for Livermore Computing, told me that, in initial tests, the CS-1 had run neural networks about five times as fast per transistor as a cluster of G.P.U.s, and had accelerated network training even more.

It all suggests one possible work-around for Moore's Law: optimizing chips for specific applications. "For now," Feldman tells the New Yorker, "progress will come through specialization."

Eric Vishria (uno de los inversores de Cerebras) resume perfectamente el reto de ingeniería que ha debido suponer la creación de un chip así con este tweet:

https://twitter.com/ericvishria/status/1428832884048109570

Saludos.

[Cadavre Exquis]

Un par de horas después de la entrada sobre el chip de Cerebras apareció este otro post, esta vez de la mano de Intel que ha dejado de ser el lider indiscutible en el mercado de los semiconductores para ver como otras compañias le comen la tostada:

45 Teraflops: Intel Unveils Details of Its 100-Billion Transistor AI Chip
Posted by EditorDavid on Monday August 23, 2021 @05:34AM from the super-semiconductors dept.

At its annual Architecture Day semiconductor event Thursday, Intel revealed new details about its powerful Ponte Vecchio chip for data centers, reports SiliconANGLE:

Intel is looking to take on Nvidia Corp. in the AI silicon market with Ponte Vecchio, which the company describes as its most complex system-on-chip or SOC to date. Ponte Vecchio features some 100 billion transistors, nearly twice as many as Nvidia's flagship A100 data center graphics processing unit. The chip's 100 billion transistors are divided among no fewer than 47 individual processing modules made using five different manufacturing processes. Normally, an SOC's processing modules are arranged side by side in a flat two-dimensional design. Ponte Vecchio, however, stacks the modules on one another in a vertical, three-dimensional structure created using Intel's Foveros technology.

The bulk of Ponte Vecchio's processing power comes from a set of modules aptly called the Compute Tiles. Each Compute Tile has eight Xe cores, GPU cores specifically optimized to run AI workloads. Every Xe core, in turn, consists of eight vector engines and eight matrix engines, processing modules specifically built to run the narrow set of mathematical operations that AI models use to turn data into insights... Intel shared early performance data about the chip in conjunction with the release of the technical details. According to the company, early Ponte Vecchio silicon has demonstrated performance of more than 45 teraflops, or about 45 trillion operations per second.

The article adds that it achieved those speeds while processing 32-bit single-precision floating-point values floating point values — and that at least one customer has already signed up to use Ponte Vecchio.

The Argonne National Laboratory will include Ponte Vecchio chips in its upcoming $500 million Aurora supercomputer. Aurora will provide one exaflop of performance when it becomes fully operational, the equivalent of a quintillion calculations per second.

A esta noticia y a la de Cerebras yo añadiría la del día 5 de agosto en la que Elon Musk dejaba caer que tenía un as en la manga llamado "Dojo":

Elon Musk Hints at Tesla's Secret Project 'Dojo' Making the Difference in Race To Full Self-Driving
Posted by msmash on Monday August 05, 2019 @12:03PM from the up-next dept.

Elon Musk set an aggressive deadline for Tesla to achieve full self-driving capability, but the electric automaker might have an ace up its sleeve that mostly went under the radar: project 'Dojo.' Electrek:

Over the weekend, Musk hinted that it could make the difference. During Tesla's Autonomy Day earlier this year, Musk and other Tesla executives gave presentations about what the company is doing to try to achieve full self-driving capability by the end of next year. While most people were focused on the unveiling of Tesla's new HW3 'Full Self-Driving Computer,' which was being explained for the first time and is now installed in all new Tesla vehicles, there was a brief mention of another computer, the Dojo computer, that Tesla is working on and it could be a game-changer.

Last weekend, Musk was asked about the secret project and while the CEO didn't reveal anything new, he did hint that it could make the difference. During Autonomy Day, Musk briefly mentioned the project 'Dojo': "We do have a major program at Tesla which we don't have enough time to talk about today called "Dojo." That's a super powerful training computer. The goal of Dojo will be to be able to take in vast amounts of data and train at a video level and do unsupervised massive training of vast amounts of video with the Dojo program -- or Dojo computer."

Como era de esperar, no hizo falta esperar mucho tiempo para averiguar en qué consistía el famoso proyecto "Dojo" puesto que, el día 20 de agosto, durante el Tesla AI day, se presentó oficialmente en sociedad:

Tesla unveils Dojo supercomputer: world’s new most powerful AI training machine
Fred Lambert | Aug. 20th 2021 3:08 am PT

At its AI Day, Tesla unveiled its Dojo supercomputer technology while flexing its growing in-house chip design talent.

The automaker claims to have developed the fastest AI training machine in the world.

For years now, Tesla has been teasing the development of a new supercomputer in-house optimized for neural net video training.

Tesla is handling an insane amount of video data from its fleet of over 1 million vehicles, which it uses to train its neural nets.

The automaker found itself unsatisfied with current hardware options to train its computer vision neural nets and believed it could do better internally.

Over the last two years, CEO Elon Musk has been teasing the development of Tesla’s own supercomputer called “Dojo.”

Last year, he even teased that Tesla’s Dojo would have a capacity of over an exaflop, which is one quintillion (1018) floating-point operations per second, or 1,000 petaFLOPS.

It could potentially makes Dojo the new most powerful supercomputer in the world.

Today, at Tesla’s AI Day, the company unveiled Dojo.

Ganesh Venkataramanan, Tesla’s senior director of Autopilot hardware and the leader of the Dojo project, led the presentation.

The engineer started by unveiling Dojo’s D1 chip, which is using 7 nanometer technology and delivers breakthrough bandwidth and compute performance:

This is the second chip designed by the Tesla team internally after the FSD chip found in the FSD computer hardware 3 in Tesla cars.

Venkataramanan had an actual D1 chip on stage:

The engineer commented on the new D1 chip:

This was entirely designed by Tesla team internally. All the way from the architecture to the package. This chip is like GPU-level compute with a CPU level flexibility and twice the network chip level IO bandwight.

Tesla claims to have achieved a significant breakthrough in chip bandwidth:

Tesla designed the chip to “seamlessly connect without any glue to each other,” and the automaker took advantage of that by connecting 500,000 nodes together.

It adds the interface, power, and thermal management, and it results in what it calls a training tile:

The result is a 9 PFlops training tile with 36TB per second of bandwight in a less than 1 cubic foot format.

Venkataramanan also had an actual Dojo training tile on stage:

The engineer commented on the piece of computing technology:

It’s unprecedented. This is an amazing piece of engineering.

However, that’s where the unveiling of actual real Dojo hardware stopped for Tesla.

The automaker revealed that it only recently ran a neural network on one of the tiles and Venkataramanan appeared to even surprised Andrej Karpathy, Tesla’s head of AI, on stage by revealing for the first time that Dojo training tile ran one of his neural networks:

But now it still has to form a compute cluster using those training tiles in order to truly build the first Dojo supercomputer.

Tesla says that it can combine 2 x 3 tiles in a tray and two trays in a computer cabinet for over 100 PFlops per cabinet:

But with their incredible bandwidth, Tesla claims that they can link those all together to create the ExaPod.

In a 10-cabinet system, Tesla’s Dojo ExaPod will break the barrier of the ExaFlop of compute – something that supercomputer makers have been trying to achieve for a long time:



Tesla hasn’t put that system together yet, but CEO Elon Musk claimed that it will be operational next year.

It would become the fatest AI training computer in the world while being power efficient and in a relatively small format for a supercomputer.

Tesla plans to use the new supercomputer to train its own neural networks to develop self-driving technology, but it also plans to make it available to other AI developers in the future.

Since it was Tesla’s first shot at developing a supercomputer in-house, the company also believes that there are a lot of room for improvements, and it is teasing 10x improvements in some levels of performance in the next version of Dojo.

Saludos.

[Derby]

https://spectrum.ieee.org/next-gen-chips-will-be-powered-from-below

NEXT-GEN CHIPS WILL BE POWERED FROM BELOW

Buried interconnects will help save Moore's Law

(...) Delivering that current to billions of transistors is quickly becoming one of the major bottlenecks in high-performance SoC design. As transistors continue to be made tinier, the interconnects that supply them with current must be packed ever closer and be made ever finer, which increases resistance and saps power. This can't go on: Without a big change in the way electrons get to and from devices on a chip, it won't matter how much smaller we can make transistors.



Fortunately, we have a promising solution: We can use a side of the silicon that's long been ignored.

Electrons have to travel a long way to get from the source that is generating them to the transistors that compute with them. In most electronics they travel along the copper traces of a printed circuit board into a package that holds the SoC, through the solder balls that connect the chip to the package, and then via on-chip interconnects to the transistors themselves. It's this last stage that really matters.

To see why, it helps to understand how chips are made. An SoC starts as a bare piece of high-quality, crystalline silicon. We first make a layer of transistors at the very top of that silicon. Next we link them together with metal interconnects to form circuits with useful computing functions. These interconnects are formed in layers called a stack, and it can take a 10-to-20-layer stack to deliver power and data to the billions of transistors on today's chips.

Those layers closest to the silicon transistors are thin and small in order to connect to the tiny transistors, but they grow in size as you go up in the stack to higher levels. It's these levels with broader interconnects that are better at delivering power because they have less resistance.



(...)The future of computing depends upon these new manufacturing techniques. Power consumption is crucial whether you're worrying about the cooling bill for a data center or the number of times you have to charge your smartphone each day. And as we continue to shrink transistors and ICs, delivering power becomes a significant on-chip challenge. BPR and back-side PDNs may well answer that challenge if engineers can overcome the complexities that come with them.