Visión de los colores - La polémica del vestido


Publicado el 27 Febrero 2015

Discromatopsias Menores. La polémica del vestido.

En el año 1959, el Dr. Roger Eleazar Zaldivar funda en Mendoza, Argentina, el Instituto Zaldivar: un centro pionero y vanguardista en cirugías oftalmológicas ambulatorias convirtiendo a Mendoza, en un polo de desarrollo e investigación en todo lo referente a oftalmología. Décadas más tarde, crea la fundación que lleva su nombre y su espíritu de responsabilidad social con más de 40.000 pacientes atendidos.

Por estas horas una información se ha esparcido por el mundo de internet convirtiéndose en algo conocido como "viral", una nota de rápida difusión y alcance superior al promedio normal.
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Una nota ejemplo:

http://www.elcolombiano.com/los-colores-de-un-vestido-el-motivo-de-la-discordia-NM1385429
Los colores de un vestido, el motivo de la discordia.

Una simple duda que una joven escocesa decidió compartir con sus seguidores en la red social Tumblr, sobre los colores de un vestido, revolucionó las redes sociales y se volvió un fenómeno viral en la noche del pasado jueves y en la mañana de este viernes.

Más de 750.000 menciones para la etiqueta #TheDress ayudan a dimensionar el alcance que tuvo la desprevenida pregunta. #WhiteAndGold y #BlackAndBlue también recibieron cientos de miles de menciones.

Blanco y dorado o negro y azul: la dicotomía

La pregunta sobre los colores del vestido parece tonta pero lo cierto es que si se extiendeentre varias personas no hay unanimidad. En parte por la iluminación externa y el contraste que tiene la foto en la pantalla y por la manera particular como cada cerebro percibe la luz y lo asocia con un color.
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LA RESPUESTA CIENTÍFICA
A cargo de los expertos del Instituto Zaldívar.
http://www.institutozaldivar.com/instituto-zaldivar

¿Por qué se ven los objetos de determinados colores?

Los objetos absorben y reflejan la luz de forma distinta dependiendo de sus características físicas, como su forma, composición, etc. El color que percibimos de un objeto es el rayo de luz que refleja. Nosotros “captamos” esos “rebotes” con diferentes longitudes de onda, gracias a la estructura de los ojos.

Las células sensoriales (fotorreceptores) de la retina que reaccionan de forma distinta a la luz y los colores se les llaman bastones y conos respectivamente.

¿Qué es una discromatopsia?

La discromatopsia es una discapacidad de la visión de los colores. Puede ser congénita, como por ejemplo, el daltonismo (la mas popular) o adquirida. Según el color involucrado y el grado de afectación se distinguen:

-Protanopia: falta total del sistema receptor para el color ROJO (ceguera para el color rojo)

-Deuteranopia: falta total del sistema receptor para el color VERDE(ceguera para el color verde)

-Tritanopia: falta total del sistema receptor para el color AZUL(ceguera para el color azul)

-Acromatopsia: es la ausencia total de la percepción de colores o ceguera para los colores azul, verde, blanco y rosa.
¿Y una discromatopsia menor?

Es aquella alteración en la visión de los colores, en la cual es difícil catalogar como anormal aquellas personas que la padecen. Estas presentan un contraste exagerado en diferentes gamas de colores, es decir, se dificulta poder diferenciar ciertos colores en contraste con otros.

Tales anomalías a menudo suelen ser atribuidas a alteraciones en la distribución de ciertos pigmentos en la mácula, dichos pigmentos son los encargados de la visión de colores ubicados en mayor densidad en la mácula, es decir, en la zona de mayor visión del ojo.

La frecuencia de estas anomalías varían según diferentes autores, pero oscila entre 3 de cada 100 personas que poseen visión cromática normal, es decir un 3%. Se han descripto ciertos genes implicados en la herencia de esta anomalía.

Se propuso una clasificación para esta entidad. Por un lado, los pequeños defectos en la diferenciación de los colores en la gama del azul, dentro de esta se ve alterada la visión del color azul más claro y azul-amarillo claros en contraste con el violeta oscuro. Y por el otro lado, los defectos menores de la gama del amarillo donde se altera la visión del amarillo claro y amarillo- azul claro.
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Con lo que,en este Complejo Cultural, consideramos resuelto el tema, salvo mejores opiniones que puedan enviarnos nuestros lectores del mundo.

A propósito, ¿de qué colores has visto el vestido?

Prof. Daniel Aníbal Galatro
danielgalatro@gmail.com
Esquel - Chubut - Argentina
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Michio Kaku - About Physics - in English


Theoretical physicist and author Michio Kaku spoke at UTA in a sold out Maverick Speakers Series lecture on Thursday. Kaku is known for his appearances on the Science Channel, and his continuing work on Einstein’s unified field theory. Before taking the stage, Kaku spoke with The Shorthorn in an exclusive interview about his experiences as a burgeoning scientist, his thoughts on the unanswered questions of science and his biggest fear for the future of humanity.

Source:
http://www.theshorthorn.com/news/kaku-explores-future-of-physics-during-lecture/article_edaac1ea-b8c6-11e4-b701-df720d6bdc9c.html

The Shorthorn: There is a story that, while you were in high school, you built an atom smasher in your garage. What drove you to take on that project?

Michio Kaku: That’s right. Ever since I was 8 years old, I was fascinated by the fact that Einstein could not finish his greatest work. What could be so hard? So I wanted to be part of this great mission to complete the theory of everything, which of course is the basis for an Oscar nominated movie, The Theory of Everything. I said to myself, “That’s for me.” But I had to do something, to be worthy of the theory of everything.

So, when I was 17 years old, I went to my mom and I said, “I’m going to build an atom smasher in the garage.” So she said, “Sure! Why not?” I assembled 400 pounds of transformer steel, 22 miles of copper wire and I built a 2.3 million electron volt betatron particle accelerator in the garage. It consumed all of the energy in the house, blew out all of the circuit breakers every time we turned it on. And my mother would say, “Why can’t he find a nice Japanese girlfriend? Why does he have to build these gigantic machines in the garage?” But you see, that got me a scholarship to Harvard. Can’t complain.

It earned the attention of a physicist, Edward Teller, father of the hydrogen bomb. He took an interest in me, and arranged for me to go to Harvard and to pursue my professional career. Now he of course wanted me to work on hydrogen bombs, so when I was applying for grad school, he made a big play for me to work at Los Alamos National Laboratories, working on hydrogen warheads. But you see, I wanted to work on something bigger. A hydrogen bomb, for me, was puny compared to the Big Bang – the creation of the universe. That’s what I really wanted to work on – the nature of the universe itself, and that’s what I do for a living.

TS: Several years ago, Texas was almost home to the Superconducting Supercollider, but these plans were scrapped. With the success of the Large Hadron Collider, what can the U.S. do to bring back these types of technology and research?

MK: Dallas was supposed to be the Vatican of physics, now it’s Geneva, Switzerland. All the publicity of the Higgs-Boson, the Large Hadron Collider, the theory of everything, all that publicity is going to Europe. And why? Well, Congress gave us a billion dollars to dig the hole, this gigantic hole. Bigger, much bigger than the hole in Geneva, Switzerland. Then they canceled the machine and gave us a second billion dollars to fill up the hole. Two billion dollars to dig a hole and fill it up. That is the wisdom of the United States Congress and it really makes you wonder: Is there intelligent life on the Earth? Certainly not in the United States Congress.

TS: What can we do to pull those technological advances back to the U.S.?

MK: Well, the Large Hadron Collider found the Higgs-Boson. Next will be dark matter. We want to create dark matter in the laboratory. So already now, different nations are competing for the next machine. The next machine may be a linear collider, we’re not sure. Japan has already said that they would like to host the next machine, beyond the Large Hadron Collider. Now for us, it means that our machines are old. We have an old machine at Brookhaven Long Island, another one at Fermilab. They’re old, and they may be shut down. The Congress is always tinkering with the idea of shutting down our great set of national laboratories, because all the thunder now is going to Switzerland. Which would be a shame, because we lost a generation. A generation of physicists was lost, because of the lack of funding here.

TS: What do you see as the most important, unanswered questions in science?

MK: The first is the origin of the universe, and that is what the LHC and the SCC is all about. We want to create a miniature universe – a miniature Big Bang. The second is the origin of the mind.

We’ve learned more in the last 15 years about the brain than in all of human history combined. Think of all the nonsense you had to learn in psychology courses. None of which was testable. None of which was measurable. We had behaviorism, Freudian psychology, all of these theories that you learn in psychology. Totally untestable. Now, we can test it, because physics allows us to calculate energy flows in the brain. From that, we can actually construct pictures of what you’re thinking. I can actually put you in an MRI machine, and you can see me and I’ll have the computer print out a picture of what you are looking at. That’s what we can do. So telepathy, telekinesis, recording memories, uploading memories, we can do it now. All this stuff you see in science fiction movies like The Matrix, Star Trek, we can do on a small scale, many of these things in the lab. And it’s all because of physics.

TS: What scares you the most about the future?

MK: I think we’re headed for what is called Type 1 Civilization, planetary civilization. Type 2 would be stellar civilization, like Star Trek. Type 3 Civilization would be galactic, like Star Wars. We are Type 0. We get our energy from dead plants, oil and coal. But we are about 100 years from being Type 1, and the question is: Will we make it? Will we make the transition from Type 0 to Type 1? It’s not clear.

A Type 1 Civilization would be progressive, scientific, multicultural. But you see, there are some people who don’t like it. They can’t articulate this, because this is a physicist’s analysis. There are some people who do not like a Type 1 Civilization. They do not like a civilization that is scientific, multicultural, progressive. These are the terrorists, and God forbid that they get access to an atomic bomb. So it’s not clear that we’ll make the transition from our fragmented Type 0 Civilization to a Type 1 Civilization, which is truly planetary.

Kaku explores future of physics during lecture

Theoretical physicist Michio Kaku presented a possible glimpse into the future during his sold-out Maverick Speakers Series lecture Thursday.

The author and frequent media personality spoke about technological and research advances with the potential to alter human civilization.

Technology that provides the ability to view information through a contact lens in real time and other devices such as smart toilets, and smart wallpaper, Kaku said, have the potential to provide up to the minute details about the user’s body and the outside world.

Before taking the stage, Michio Kaku spoke with The Shorthorn in an exclusive interview about his experiences as a burgeoning scientist, his thoughts on the unanswered questions of science and…

“What we’re seeing is a transition to what I call perfect capitalism,” he said. “In other words, the consumer knows exactly what things really cost. In your contact lens, you scan all of the items and you see exactly what things cost.”

By possessing these technologies, Kaku said, the balance of power switches to the consumer, and this transfer of power will create clear winners and losers.

“When you choose a job, be sure you don’t choose a job like being a blacksmith or a wagon maker,” he said. “We don’t have blacksmiths anymore. We don’t have wagon makers anymore, but nobody cries about this.”

The lower prices of technology, combined with faster production methods, will allow consumers to work directly with producers on personalized products, Kaku said, and this one-on-one work with the producer means middlemen, such as brokers and agents, will disappear.

Theater arts junior Jasmine Davis said she wasn’t familiar with Kaku before his lecture, but attended at the insistence of a friend.

“I don’t really know much about physics, but I really liked how he made a lot of it understandable,” she said. “Also, being a theater major, I was really interested in the weird, future clothes the actors were wearing in the short movie he showed.”

Martin High School student Thomas Davis said he heard about the lecture from his physics teacher, and couldn’t resist seeing him live.

“I’m the president of the physics club, and our teacher, who is a UTA alum, told us about it,” he said. “I see him on TV all the time, so seeing him in person was amazing.”

After the lecture, Kaku took questions from the audience, and expanded on his views about the need for scientists to engage the public and show how science can drive and create new industries.

“The engine of prosperity runs on science,” he said.

@mattsfulkerson
matthew.fulkerson@mavs.uta.edu


Michio Kaku - About Physics - in English


Theoretical physicist and author Michio Kaku spoke at UTA in a sold out Maverick Speakers Series lecture on Thursday. Kaku is known for his appearances on the Science Channel, and his continuing work on Einstein’s unified field theory. Before taking the stage, Kaku spoke with The Shorthorn in an exclusive interview about his experiences as a burgeoning scientist, his thoughts on the unanswered questions of science and his biggest fear for the future of humanity.

Source:
http://www.theshorthorn.com/news/kaku-explores-future-of-physics-during-lecture/article_edaac1ea-b8c6-11e4-b701-df720d6bdc9c.html

The Shorthorn: There is a story that, while you were in high school, you built an atom smasher in your garage. What drove you to take on that project?

Michio Kaku: That’s right. Ever since I was 8 years old, I was fascinated by the fact that Einstein could not finish his greatest work. What could be so hard? So I wanted to be part of this great mission to complete the theory of everything, which of course is the basis for an Oscar nominated movie, The Theory of Everything. I said to myself, “That’s for me.” But I had to do something, to be worthy of the theory of everything.

So, when I was 17 years old, I went to my mom and I said, “I’m going to build an atom smasher in the garage.” So she said, “Sure! Why not?” I assembled 400 pounds of transformer steel, 22 miles of copper wire and I built a 2.3 million electron volt betatron particle accelerator in the garage. It consumed all of the energy in the house, blew out all of the circuit breakers every time we turned it on. And my mother would say, “Why can’t he find a nice Japanese girlfriend? Why does he have to build these gigantic machines in the garage?” But you see, that got me a scholarship to Harvard. Can’t complain.

It earned the attention of a physicist, Edward Teller, father of the hydrogen bomb. He took an interest in me, and arranged for me to go to Harvard and to pursue my professional career. Now he of course wanted me to work on hydrogen bombs, so when I was applying for grad school, he made a big play for me to work at Los Alamos National Laboratories, working on hydrogen warheads. But you see, I wanted to work on something bigger. A hydrogen bomb, for me, was puny compared to the Big Bang – the creation of the universe. That’s what I really wanted to work on – the nature of the universe itself, and that’s what I do for a living.

TS: Several years ago, Texas was almost home to the Superconducting Supercollider, but these plans were scrapped. With the success of the Large Hadron Collider, what can the U.S. do to bring back these types of technology and research?

MK: Dallas was supposed to be the Vatican of physics, now it’s Geneva, Switzerland. All the publicity of the Higgs-Boson, the Large Hadron Collider, the theory of everything, all that publicity is going to Europe. And why? Well, Congress gave us a billion dollars to dig the hole, this gigantic hole. Bigger, much bigger than the hole in Geneva, Switzerland. Then they canceled the machine and gave us a second billion dollars to fill up the hole. Two billion dollars to dig a hole and fill it up. That is the wisdom of the United States Congress and it really makes you wonder: Is there intelligent life on the Earth? Certainly not in the United States Congress.

TS: What can we do to pull those technological advances back to the U.S.?

MK: Well, the Large Hadron Collider found the Higgs-Boson. Next will be dark matter. We want to create dark matter in the laboratory. So already now, different nations are competing for the next machine. The next machine may be a linear collider, we’re not sure. Japan has already said that they would like to host the next machine, beyond the Large Hadron Collider. Now for us, it means that our machines are old. We have an old machine at Brookhaven Long Island, another one at Fermilab. They’re old, and they may be shut down. The Congress is always tinkering with the idea of shutting down our great set of national laboratories, because all the thunder now is going to Switzerland. Which would be a shame, because we lost a generation. A generation of physicists was lost, because of the lack of funding here.

TS: What do you see as the most important, unanswered questions in science?

MK: The first is the origin of the universe, and that is what the LHC and the SCC is all about. We want to create a miniature universe – a miniature Big Bang. The second is the origin of the mind.

We’ve learned more in the last 15 years about the brain than in all of human history combined. Think of all the nonsense you had to learn in psychology courses. None of which was testable. None of which was measurable. We had behaviorism, Freudian psychology, all of these theories that you learn in psychology. Totally untestable. Now, we can test it, because physics allows us to calculate energy flows in the brain. From that, we can actually construct pictures of what you’re thinking. I can actually put you in an MRI machine, and you can see me and I’ll have the computer print out a picture of what you are looking at. That’s what we can do. So telepathy, telekinesis, recording memories, uploading memories, we can do it now. All this stuff you see in science fiction movies like The Matrix, Star Trek, we can do on a small scale, many of these things in the lab. And it’s all because of physics.

TS: What scares you the most about the future?

MK: I think we’re headed for what is called Type 1 Civilization, planetary civilization. Type 2 would be stellar civilization, like Star Trek. Type 3 Civilization would be galactic, like Star Wars. We are Type 0. We get our energy from dead plants, oil and coal. But we are about 100 years from being Type 1, and the question is: Will we make it? Will we make the transition from Type 0 to Type 1? It’s not clear.

A Type 1 Civilization would be progressive, scientific, multicultural. But you see, there are some people who don’t like it. They can’t articulate this, because this is a physicist’s analysis. There are some people who do not like a Type 1 Civilization. They do not like a civilization that is scientific, multicultural, progressive. These are the terrorists, and God forbid that they get access to an atomic bomb. So it’s not clear that we’ll make the transition from our fragmented Type 0 Civilization to a Type 1 Civilization, which is truly planetary.

Kaku explores future of physics during lecture

Theoretical physicist Michio Kaku presented a possible glimpse into the future during his sold-out Maverick Speakers Series lecture Thursday.

The author and frequent media personality spoke about technological and research advances with the potential to alter human civilization.

Technology that provides the ability to view information through a contact lens in real time and other devices such as smart toilets, and smart wallpaper, Kaku said, have the potential to provide up to the minute details about the user’s body and the outside world.

Before taking the stage, Michio Kaku spoke with The Shorthorn in an exclusive interview about his experiences as a burgeoning scientist, his thoughts on the unanswered questions of science and…

“What we’re seeing is a transition to what I call perfect capitalism,” he said. “In other words, the consumer knows exactly what things really cost. In your contact lens, you scan all of the items and you see exactly what things cost.”

By possessing these technologies, Kaku said, the balance of power switches to the consumer, and this transfer of power will create clear winners and losers.

“When you choose a job, be sure you don’t choose a job like being a blacksmith or a wagon maker,” he said. “We don’t have blacksmiths anymore. We don’t have wagon makers anymore, but nobody cries about this.”

The lower prices of technology, combined with faster production methods, will allow consumers to work directly with producers on personalized products, Kaku said, and this one-on-one work with the producer means middlemen, such as brokers and agents, will disappear.

Theater arts junior Jasmine Davis said she wasn’t familiar with Kaku before his lecture, but attended at the insistence of a friend.

“I don’t really know much about physics, but I really liked how he made a lot of it understandable,” she said. “Also, being a theater major, I was really interested in the weird, future clothes the actors were wearing in the short movie he showed.”

Martin High School student Thomas Davis said he heard about the lecture from his physics teacher, and couldn’t resist seeing him live.

“I’m the president of the physics club, and our teacher, who is a UTA alum, told us about it,” he said. “I see him on TV all the time, so seeing him in person was amazing.”

After the lecture, Kaku took questions from the audience, and expanded on his views about the need for scientists to engage the public and show how science can drive and create new industries.

“The engine of prosperity runs on science,” he said.

@mattsfulkerson
matthew.fulkerson@mavs.uta.edu


¿Y si no hubo 'Big Bang'? - EUROPA PRESS


Actualizado 10/02/2015 13:01:19 CET

MADRID, 9 Feb. (EUROPA PRESS) -

El universo puede haber existido desde siempre, de acuerdo con un nuevo modelo que aplica términos de corrección cuántica para complementar la teoría de la relatividad general de Einstein. El modelo también puede explicar la materia oscura y la energía oscura, la resolución de varios problemas a la vez.

La edad ampliamente aceptada del universo, según las estimaciones de la relatividad general, es de 13.800 millones de años. En un principio, se pensó que todo lo que existe haber ocupado un único punto infinitamente denso, o singularidad. Sólo después de este punto comenzó a expandirse en un 'Big Bang', que hizo que el universo comenzase oficialmente.

Aunque la singularidad del 'Big Bang' surge directa e inevitable de las matemáticas de la relatividad general, algunos científicos lo ven problemático porque las matemáticas sólo pueden explicar lo que sucedió inmediatamente después, no antes o en la singularidad.

"La singularidad del Big Bang es el problema más grave de la relatividad general, porque las leyes de la Física parecen romperse ahí abajo", dijo a Phys.org Ahmed Farag Ali, de la Universidad de Benha (Egipto).

Ali y el coautor Saurya Das de la Universidad de Lethbridge en Alberta, Canadá, han mostrado en un artículo publicado en Physics Letters B que la singularidad del Big Bang puede ser resuelta por su nuevo modelo, en el que el universo no tiene principio ni fin.

Estos físicos enfatizan que sus términos de corrección cuántica no se aplican 'ad hoc' en un intento de eliminar específicamente la singularidad del 'Big Bang'. Su trabajo se basa en las ideas por el físico teórico David Bohm, quien también es conocido por sus contribuciones a la Filosofía de la Física. A partir de la década de 1950, Bohm exploró reemplazar geodesias clásicas (el camino más corto entre dos puntos de una superficie curva) con trayectorias cuánticas.

En su artículo, Ali y Das aplican estas trayectorias de Bohm a una ecuación desarrollada en la década de 1950 por el físico Amal Kumar Raychaudhuri, en la Universidad Presidency en Calcuta, India. Raychaudhuri fue también maestro de Das cuando era un estudiante universitario de esta institución en los años 90.

Usando la ecuación de Raychaudhuri cuánticamente corregida, Ali y Das derivan ecuaciones de Friedmann cuánticamente corregidas, que describen la expansión y evolución del universo (incluyendo el Big Bang) en el contexto de la relatividad general. Aunque no es una verdadera teoría de la gravedad cuántica, el modelo contiene elementos tanto de la teoría cuántica como de la relatividad general.

NO HAY SINGULARIDADES NI COSAS OSCURAS

Además de no predecir una singularidad del Big Bang, el nuevo modelo no predice una singularidad 'big crunch' tampoco. En la relatividad general, un posible destino del universo es que comienza a contraerse hasta que se derrumba sobre sí mismo en una gran crisis y se convierte en un punto infinitamente denso, una vez más.

Ali y Das explican en su artículo que su modelo evita singularidades debido a una diferencia clave entre geodesias clásicas y trayectorias de Bohm. Las geodesias clásicas finalmente se cruzan entre sí, y los puntos en los que convergen son singularidades. En contraste, las trayectorias de Bohm nunca se cruzan entre sí, por lo que las singularidades no aparecen en las ecuaciones.

En términos cosmológicos, los científicos explican que las correcciones cuánticas pueden ser consideradas como una constante cosmológica (sin la necesidad de la energía oscura) y un plazo de radiación. Estos términos mantienen el universo en un tamaño finito, y por lo tanto le dan una edad infinita. Los términos también hacen predicciones que coinciden estrechamente con las observaciones actuales de la constante cosmológica y la densidad del universo.

En términos físicos, el modelo describe el universo como lleno de un fluido cuántico. Los científicos proponen que este líquido podría estar compuesto por partículas hipotéticas denominadas gravitones, sin masa, que median en la fuerza de gravedad. Si existen, se cree que los gravitones juegan un papel clave en una teoría de la gravedad cuántica.

+CIENCIAPLUS

¿Y si no hubo 'Big Bang'? - EUROPA PRESS


Actualizado 10/02/2015 13:01:19 CET

MADRID, 9 Feb. (EUROPA PRESS) -

El universo puede haber existido desde siempre, de acuerdo con un nuevo modelo que aplica términos de corrección cuántica para complementar la teoría de la relatividad general de Einstein. El modelo también puede explicar la materia oscura y la energía oscura, la resolución de varios problemas a la vez.

La edad ampliamente aceptada del universo, según las estimaciones de la relatividad general, es de 13.800 millones de años. En un principio, se pensó que todo lo que existe haber ocupado un único punto infinitamente denso, o singularidad. Sólo después de este punto comenzó a expandirse en un 'Big Bang', que hizo que el universo comenzase oficialmente.

Aunque la singularidad del 'Big Bang' surge directa e inevitable de las matemáticas de la relatividad general, algunos científicos lo ven problemático porque las matemáticas sólo pueden explicar lo que sucedió inmediatamente después, no antes o en la singularidad.

"La singularidad del Big Bang es el problema más grave de la relatividad general, porque las leyes de la Física parecen romperse ahí abajo", dijo a Phys.org Ahmed Farag Ali, de la Universidad de Benha (Egipto).

Ali y el coautor Saurya Das de la Universidad de Lethbridge en Alberta, Canadá, han mostrado en un artículo publicado en Physics Letters B que la singularidad del Big Bang puede ser resuelta por su nuevo modelo, en el que el universo no tiene principio ni fin.

Estos físicos enfatizan que sus términos de corrección cuántica no se aplican 'ad hoc' en un intento de eliminar específicamente la singularidad del 'Big Bang'. Su trabajo se basa en las ideas por el físico teórico David Bohm, quien también es conocido por sus contribuciones a la Filosofía de la Física. A partir de la década de 1950, Bohm exploró reemplazar geodesias clásicas (el camino más corto entre dos puntos de una superficie curva) con trayectorias cuánticas.

En su artículo, Ali y Das aplican estas trayectorias de Bohm a una ecuación desarrollada en la década de 1950 por el físico Amal Kumar Raychaudhuri, en la Universidad Presidency en Calcuta, India. Raychaudhuri fue también maestro de Das cuando era un estudiante universitario de esta institución en los años 90.

Usando la ecuación de Raychaudhuri cuánticamente corregida, Ali y Das derivan ecuaciones de Friedmann cuánticamente corregidas, que describen la expansión y evolución del universo (incluyendo el Big Bang) en el contexto de la relatividad general. Aunque no es una verdadera teoría de la gravedad cuántica, el modelo contiene elementos tanto de la teoría cuántica como de la relatividad general.

NO HAY SINGULARIDADES NI COSAS OSCURAS

Además de no predecir una singularidad del Big Bang, el nuevo modelo no predice una singularidad 'big crunch' tampoco. En la relatividad general, un posible destino del universo es que comienza a contraerse hasta que se derrumba sobre sí mismo en una gran crisis y se convierte en un punto infinitamente denso, una vez más.

Ali y Das explican en su artículo que su modelo evita singularidades debido a una diferencia clave entre geodesias clásicas y trayectorias de Bohm. Las geodesias clásicas finalmente se cruzan entre sí, y los puntos en los que convergen son singularidades. En contraste, las trayectorias de Bohm nunca se cruzan entre sí, por lo que las singularidades no aparecen en las ecuaciones.

En términos cosmológicos, los científicos explican que las correcciones cuánticas pueden ser consideradas como una constante cosmológica (sin la necesidad de la energía oscura) y un plazo de radiación. Estos términos mantienen el universo en un tamaño finito, y por lo tanto le dan una edad infinita. Los términos también hacen predicciones que coinciden estrechamente con las observaciones actuales de la constante cosmológica y la densidad del universo.

En términos físicos, el modelo describe el universo como lleno de un fluido cuántico. Los científicos proponen que este líquido podría estar compuesto por partículas hipotéticas denominadas gravitones, sin masa, que median en la fuerza de gravedad. Si existen, se cree que los gravitones juegan un papel clave en una teoría de la gravedad cuántica.

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