QUANTUM COMPUTER

A BREAKTHROUGH IS COMING

"Quantum computers can keep up with the (true), complexity of nature." “Accurate modeling, has applications for engineering, medicine, energy production and much more”: Richard Feynman

From quantamagazine

Although a quantum computer (QC), prototype already works and is marketed  (D-Wave S.), installed in modules of 5 x 5m and heights of 7m., insulated with fiberglass from the environment, with 50 qbits inserted in silica receivers, protected by a near zero absolute cooling, with softwares adapted to electrons, with environmental insulation, to avoid interference and errors. What is missing ... What is left over? There is an excess of optimism, such as that of Geordie Rose, co-founder of D-Wave System, who has made some predictions: One) 2020, using a QC, the NASA will identify 40 light years from Earth, a planet with atmosphere and oceans of liquid water, similar to the Earth. Two) 2023, Experiments with QCs, will demonstrate the existence of parallel universes. Three) 2028: QCs will play a critical role in creating robots, which will match everything a human does. On the other hand, Google, Intel and IBM, also have prototypes of QCs, not commercialized of 45 qbits, although they hope to escalate  the number of their qbits to 1000 or more, in order to be able to predict climatic changes, perform data encryption (100%, safe), develop new materials, etc. What is missing? 1) Avoid decoherence (qbits collapse), induced by noise, temperature changes, vibrations. Given this fragility, the qbits, require temperatures close to absolute zero (-273 ^oC Celsius), to remain stable. 2) New software and interconnect technologies are needed to take advantage of the gigantic processing power of QCs. As it is known while in classical computers (CC), a bit (transistor), supposes 2 separate states (0 and 1), in a  QC, a qbit is 0 and 1 at the same time (superposition), a phenomenon that together with entanglement (combinations of qbits  superpositions), allow a QC, to calculate in hours the  complex modeling  of a molecule, which possibly would take years to a CC. 300 combinations of exponential superposition  of qbits would produce more overlapping states than existing atoms in the visible universe. 3) There are 6 to 7 different types of qubits, although only 3 or 4 are used. To obtain a superposition, 2 qubits are needed and for an entanglement more than 3. Some qbits need superconductors (where electrons flow without resistance), others: oscillating charges of ions kept fixed by lasers, also silica qbits with a single electron, controlled by microwaves. 4) Increase the number of qbits to 1 million. Continue working with QC simulators. Increase the number of math softwares. Improve the accuracy of qbits controller microwaves. 5) Given the enormous amounts of money to be invested, it is important to have a coordinated work strategy between universities, governments and industry. 6) Promote the growth of artificial intelligence (AI), through the use of QCs. 7) Establish the supremacy of   QCs over the CCs, solving problems that the latter cannot do. Establish new ways (faster, more efficient), to perform certain calculations, in order to facilitate modeling of the brain, of complex molecules, of factoring large numbers solving encryption problems, taking as an example the Shor's algorithm (factorization of large numbers), of great practical contributions. According to Scott Aronson (Texas University), QCs must solve certain problems, better than CCs. It is important that QCs can solve the random circuit sampling problem (take random efficient quantum circuits and generate samples for external distribution), build quantum circuits of at least a certain minimum size, with which CCs, do not count. 8) Reduce the error, especially now that the number of gates and qbits must be increased. The most crucial mistake is that which occurs every time a gate is used. Try that error for gates of qbits, be around: 0.1%. 9) How much is missing to have a universal quantum computer? Google that favor the supremacy of QCs, hopes to present one of them, at the end of 2019. Without ruling on the date: IBM, IonQ, Rigetti and Harvard University, say it will be very soon. Harvard University that   uses rubidium atoms and Microsof atoms that uses topological qbits, need more time. Since silicon qbits are fixed and need to be individually calibrated,they  will have a difficult task at  time of increasing the number of their qbits. Trapped ions give more time to make sure of their collapse, due to environmental noise. On the other hand, its gates are very slow allowing ions to move, when they are not needed. Some think that   qbits should adopt 2 bit qualities of CCs: be easily scalable and impeccable. 10) Anything else? According to Adam Bouland (California, University, Berkeley), after QCs solve the problem of random circuit sampling, there will be others, especially everyday tasks: financial services, AI, chemistry, creation of  QCs capable of self-eliminating their errors in real time, so that at  the end, they will  offer calculations without errors, which will require massive amounts of error-correcting qbits, connected to each logic gate.

QUANTIC BRAIN

QUANTIC BRAIN

From quantamagazine

A theoretical analysis of the results of behavioral experiments performed in rats (Sechzer JA, Lieberman KW, Alexander GJ, Weidman D and Stokes PE. BiolPsychiatry, 1986; 21 (13): 1258-66), by Matthew Fisher, a theoretical physicist of the University of California, USA, has begun to generate controversy and capture the attention of  international scientific community. If subsequent experiments, to be performed by Fisher and collaborators achieve similar results to those of Sechzer JA, then Fisher could be the next winner of the Nobel Prize in Medicine for opening a new branch of medicine, inductive in turn of a second wave of biological psychiatry. A saga that seems to have been reactivated in 1986, when Fisher devastated by the effects of  a major depression that he suffered decided to follow the track to his own illness. What better then to investigate the mechanisms and behavioral effects of a simple antidepressant: Lithium. Fisher would spend a long time analyzing in depth the effects of 2 isotopes of lithium, chemical entities only different in the number of their nuclear neutrons. The experiment performed by Sechzer JA et al. consisted of administering salts of  2 stable, non-radioactive isotopes of lithium: Li-6 and Li-7 to 3-month-old rats: before, during gestation and during lactation. Li-6- puerperal rats were more affectionate, more cared for, and more frequently breastfed her offspring, while Li-6 and control mothers ignored their offspring and nursed them infrequently. For Fisher these behavioral differences lie in the nuclear spin of each isotope of Lithium, a quantum property that affects the time an atom can remain in entanglement quantum state, isolated from its environment. The smaller the spin of an atom, the lower the interaction of the nucleus with the electric and magnetic fields, having a  quantum decoherence (passage from a quantum entanglement  state  to a classical physical state), slower. By having the Li-6 and Li-7 different numbers of neutrons have different spins. Therefore, Li-7 exhibits too fast decoherence,  for quantum cognition purposes, while Li-6 remains entangled longer, thereby having different behavioral effects.

Hypothesis that suggests a role for quantum mechanisms  in the cognitive process. Fisher believes that the storage of brain quantum information is mediated by phosphorus atoms, which have a half-spin  -a low number- that would make possible long periods of coherence, capable of being further prolonged, if bound to calcium. Fisher thinks Posner molecules (Ca + P) could play the role of a natural brain qbit. After long reflections Fisher (Annals of Physics), thinks that the quantum cellular process begins with a pyrophosphate (2 phosphates released from an ATP). The interaction between the spins of these 2 phosphates causes them to become entangled and can be paired in 4 forms: 3 configurations (triplet/weakly entangled state), which are added to the total spin of one, and a fourth possibility: singlet (maximum entanglement) , capable of producing a zero spin, crucial for quantum computation. Enzymes break   entangled phosphates in 2 free phosphate ions, which remain entangled  even when separated (fast process in singlet state), being able to combine with calcium ions and oxygen becoming  Posner molecules. Neither calcium nor O atoms have nuclear spin to preserve the one-half  total: crucial spin to maintain long periods of coherence, thus protecting the entangled pairs of external interference, maintaining  its consistency for hours, days, weeks, distributed in  long brain distances, influencing the liberation of neurotransmitters and activating neuronal synapses.

CEREBRO CUANTICO

Un análisis teórico de los resultados de experimentos conductuales realizados en ratas (Sechzer JA, Lieberman KW, Alexander GJ, Weidman D y Stokes PE Biol Psychiatry. 1986;21(13):1258-66), realizado   por  Matthew Fisher, un físico teórico de la Universidad de California, USA, ha empezado a generar  controversia y captar  la atención de la comunidad científica mundial. Si los  experimentos subsiguientes, a ser realizados por Fisher y colaboradores logran  resultados similares a los de  Sechzer JA, entonces Fisher,  podría ser  el próximo  ganador del Premio Nobel de Medicina por   aperturar una nueva rama de la medicina inductora a su vez  de  una segunda gran ola de psiquiatría biológica. Una  saga que parece haberse reactivado   en  1986, cuando Fisher devastado por los efectos de la depresión mayor que padecía  decidió  seguirle  la pista  a  su propia enfermedad. Que mejor  entonces que investigar  los  mecanismos y efectos conductuales de un   antidepresivo simple: el Litio. Fisher pasaría  largo tiempo analizando  de profundis los efectos de 2 isotopos del litio, entes químicos tan solo diferentes en el número de sus neutrones nucleares.  El experimento de Sechzer JA et al, había consistido  en administrar sales de  2 isotopos  estables, no radioactivos de litio: Li-6 y Li-7 a ratas de  3 meses de edad: antes, durante la gestación y durante  la lactancia. Las ratas puérperas  que recibieron  Li-6,  mostraron más afecto, prodigaron más cuidados y amamantaron más frecuentemente a  sus crías, mientras que las que recibieron  Li-7 y las madres controles ignoraron a sus crías y las cuidaron  infrecuentemente. Para Fisher estas diferencias conductuales  radican en el spin nuclear de cada isotopo de Litio,  una propiedad cuántica que afecta al tiempo que un átomo pueda permanecer en estado cuántico entrelazado aislado de su medio ambiente. Cuanto menor es el spin de un átomo,  menor será la interacción del  núcleo con los campos eléctrico y magnético, siendo su decoherencia cuántica  (paso de un estado cuántico entrelazado a un  estado físico clásico),  más lenta. Al tener  el Li-6 y el Li-7 diferente números de neutrones tienen diferentes spins. Por  ello, el Li-7 exhibe una decoherencia,  demasiado   rápida para  propósitos de cognición cuántica,     mientras que el Li-6 permanece  entrelazado  más tiempo, teniendo por ello  diferentes efectos   conductuales.

Hipótesis que sugiere un rol  para los procesos cuánticos en el proceso cognitivo. Fisher  cree que  el almacenamiento de la   información cuántica cerebral es mediada por    átomos de Fosforo, que tienen un spin de una mitad -un numero bajo- que haría  posible tiempos prolongados de coherencia, capaces de ser prolongados  aún más,   si se unen al calcio. Fisher piensa que las moléculas de Posner (Ca +P), podrían hacer el papel de un qbit natural  cerebral.  Tras largas reflexiones Fisher (Annals of Physics), piensa que el proceso celular cuántico se inicia con un  pirofosfato (2 fosfatos liberados de un ATP). La interacción entre los spins de estos  2 fosfatos hace que devengan en  entrelazados, pudiendo aparearse en 4 formas: 3  configuraciones (estado triple/débilmente entrelazado), que se añaden al spin total de uno, y una cuarta posibilidad: singlet (entrelazamiento máximo), capaz de producir un spin zero,   crucial para la computación  cuántica. Las enzimas rompen los fosfatos  entrelazados en 2 iones fosfatos libres,  que continúan permaneciendo  entrelazados  aun cuando estén  separados (proceso veloz  en estado de   singlet), pudiendo combinarse con iones de calcio y oxigeno deviniendo en   moléculas de Posner. Ni el  calcio   ni  los  átomos de O tienen spin nuclear  para preservar el  one-half total:  spin crucial para mantener largos periodos de  coherencia, protegiendo de este modo a los pares  entrelazados   de la  interferencia externa, manteniéndose  la  coherencia  por horas, días, semanas, distribuyéndose por largas  distancias  cerebrales, influenciando la liberación de  neurotransmisores y activando las  sinapsis neuronales.

QUANTUM COMPUTER

THE CHALLENGE: QUANTUM COMPUTERS

Academic researchers that try to build quantum computers, face enormous challenges. Some believe completing the construction of one of them could take 40 years, starting today. Difficulties: a) While a regular computer stores information using bits: 0s and 1s (for discernible movements, like: up-down, etc.), quantum computers would store information of millions of electrons with 0s and 1s, in superposition states (qubits), mobilized simultaneously in all directions, performing million of computations at the same time. b) Given the increasing exponential rate of calculations, many of these can be canceled by their exponential complexity, in order to protect the system. Interactions (intertwinning) of several qubits, can collapse an entire network of entangled qubits. c) Although the high speed and computational complexity prevent inserting in quantum computers, adequate control mechanisms, researchers   are gradually correcting software errors, especially in areas of entangled qubits, while the calculations are completed. d) At this time, most calculations are only possible at the end of quantum computing processes. e) Another form of control, is selecting the most frequent final answers, discarding the remaining as noise. f) Finally, exposure  of quantum computers  to the environment or human bodies -not accustomed to obey quantum laws-  not only deteriorates (quantum decoherence), calculations  of quantum computers, but induces quantum computers  to use again   regular binary calculations. Therefore, it is necessary to isolate quantum computers to operate and maintain their quantum coherence. Given these difficulties, some scholars are developing analogs of quantum computers with 16 digits base (qudits), assuming any number of states-d, for certain quantum calculations.  It is expected soon, that an analog quantum simulator can compute in seconds, quantum equations of motion of about 100 atoms. Using 16 digits base, it is possible to store 1  qudit in a single atom. With these achievements, it is expected to calculate the age of the universe in hours, the possible folds of particular proteins, predicting global climate change, etc. An analog simulator (2002) placed in the Max Planck Institute performed quantum equations of motion of atoms in superfluid and insulating systems and in cold trapped atoms.

EL DESAFIO: COMPUTADORAS CUÁNTICAS

La mayoría de investigadores académicos que intentan  construir computadoras cuánticas, enfrentan enormes  desafíos. Algunos creen que finalizar la construcción de una de ellas, podría demorar  40 años, a partir de hoy. Dificultades :  a) Mientras una computadora  regular almacena información empleando bits: 0s y 1s (para movimientos discernibles: arriba-abajo, etc.),  las computadoras cuánticas  almacenarían  información de millones de electrones en estados de superposición  :  0s y 1s a la vez (qubits), movilizándose  al mismo tiempo en todas  direcciones, realizando simultáneamente millones de computaciones.  b) Ante la  creciente velocidad exponencial de los cálculos, muchos de estos pueden ser cancelados por su propia complejidad exponencial, a fin de  proteger al sistema. Las interacciones (intertwinning),  de varios  qubits,  pueden colapsar  una red entera de  entangled qubits. c) Aunque la elevada   velocidad y complejidad de los cálculos, impiden  insertar en las computadoras cuánticas, adecuados mecanismos de control, poco a poco se  introducen  softwares de corrección de errores, especialmente en áreas de  entangled qubits,  mientras se   completan los cálculos. d) De momento, ciertos cálculos solo son posibles  al término de los procesos  de computación  cuántica. e) Otra forma de control es la selección de las respuestas finales   más frecuentes, descartando las restantes como ruido. f) Finalmente, el contacto con el medio ambiente o  cuerpos humanos  -no habituados a  obedecer leyes cuánticas- no solo deteriora (quantum decoherence), el  funcionamiento  de las  computadoras cuánticas, sino que induce a que estas  regresionen a  métodos de cálculos binarios regulares. Por ello, es  necesario aislar a las  computadoras cuánticas para que funcionen y mantengan su coherencia cuántica. Ante estas dificultades, algunos académicos desarrollan análogos de computadoras cuánticas con bases de 16 dígitos (qudits),  asumiéndose  cualquier número de estados-d, para realizar ciertos cálculos cuánticos.   Se espera  pronto, que un  simulador cuántico analógico pueda  computar en pocos segundos, ecuaciones cuánticas del movimiento de unos  100 átomos. Empleando  bases de  16 dígitos es posible almacenar 1 qudit, en un solo átomo. Con estos logros, se espera calcular  en horas la  edad del universo, los posibles pliegues de proteínas particulares, predecir  cambios climáticos globales, etc. Un simulador análogo (2002) del Instituto Max Planck,  ya  realiza ecuaciones cuánticas del movimiento de átomos en  superfluidos y aislantes y de  átomos atrapados en frio.