Ronald Lawrence Mallett (born March 30, 1945) is an American theoretical physicist, academic and author. He has been a faculty member of the University of Connecticut since 1975 and is best known for his position on the possibility of time travel.
Mallett was born in Roaring Spring, Pennsylvania, on March 30, 1945, and grew up in The Bronx in New York City. When he was 10 years old, his father died at age 33 of a heart attack in 1955 , which made him depressed and devastated. About one year later, at age 11, Mallett found a Classics Illustrated comic book version of H.G. Wells' The Time Machine' in 1956'. Inspired by this literature, he resolved to travel back in time to save his father.[1] This idea became a lifelong obsession and the basis of his research into time travel. Mallett served in the United States Air Force for four years, during the Vietnam War. He returned to civilian life in 1966. This was the year that the science fiction TV series Star Trek started, in which he "quickly became immersed". During its first season, Mallett watched the episode The City on the Edge of Forever that "involved both the theme of time travel and lost love", and this became his favorite of the entire series.[2]
In 1973, when he was 28 years old, Mallett earned his Ph.D. in physics from Pennsylvania State University. In the same year, he received the Graduate Assistant Award for Excellence in Teaching.[3]
Mallett's plans for a time machine are based upon a ring laser's properties in the context of Einstein's general theory of relativity. Mallett first argued that the ring laser would produce a limited amount of frame-dragging which might be measured experimentally, saying:[9]
"In Einstein's General Theory of Relativity, both matter and energy can create a gravitational field. This means that the energy of a light beam can produce a gravitational field. My current research considers both the weak and strong gravitational fields produced by a single continuously circulating unidirectional beam of light. In the weak gravitational field of an unidirectional ring laser, it is predicted that a spinning neutral particle, when placed in the ring, is dragged around by the resulting gravitational field."
In a later paper, Mallett argued that at sufficient energies, the circulating laser might produce not just frame-dragging but also closed timelike curves (CTC), allowing time travel into the past:[10]
For the strong gravitational field of a circulating cylinder of light, I have found new exact solutions of the Einstein field equations for the exterior and interior gravitational fields of the light cylinder. The exterior gravitational field is shown to contain closed timelike lines.
The presence of closed timelike lines indicates the possibility of time travel into the past. This creates the foundation for a time machine based on a circulating cylinder of light.
Mallett's book, Time Traveler: A Scientist's Personal Mission to Make Time Travel a Reality, co-written with author Bruce Henderson, was published in 2006. In June 2008, motion picture director Spike Lee's production company announced it had acquired the film rights to Mallett's book.[11] Lee planned to co-write the movie script and direct the picture.[12] Lee's project was never completed.[13]
In 2006, Mallett declared that the possibility of time travel using a method based on a circulating light beam could be verified within the following decade. Mallett used general relativity to attempt to substantiate his claims.[14] He created a prototype illustrating how lasers could be used to create a circulating beam of light that twists space and time, and has an equation which he claimed supports his theory.[15][16]
In a paper by Ken Olum and Allen Everett,[17] the authors claimed to have found problems with Mallett's analysis. One of their objections is that the spacetime which Mallett used in his analysis contains a singularity even when the power to the laser is off, which would not be expected to arise naturally if the circulating laser were activated in previously empty space. Mallett has not offered a published response to Olum and Everett, but in his book Time Traveler, he mentions that he was unable to directly model the optical fiber or photonic crystal which bends the light's path as it travels through it, so the light circulates around rather than moving in a straight line; as a substitute, he chose to include a "line source" (a type of one-dimensional singularity) which would act as a "geometric constraint", bending spacetime in such a way that the light would circulate around on a helix-shaped path in vacuum[18] (for an older solution involving an infinite cylinder which creates CTCs, in this case due to the cylinder's own rotation rather than light circulating around it, see the Tipler cylinder). He notes that closed timelike curves are present in a spacetime containing both the line source and the circulating light, while they are not present in a spacetime containing only the line source, so that "the closed loops in time had been produced by the circulating flow of light, and not by the non-moving line source."[19] However, he does not provide any additional argument as to why we should expect to see closed timelike curves in a different spacetime where there is no line source, and where the light is caused to circulate due to passing through a physical substance like a photonic crystal rather than circulating in vacuum due to the curved spacetime around the line source.
Another objection by Olum and Everett is that even if Mallett's choice of spacetime were correct, the energy required to twist spacetime sufficiently would be huge, and that with lasers of the type in use today the ring would have to be much larger in circumference than the observable universe. At one point, Mallett agreed that in vacuum, the energy requirements would be impractical but noted that the energy required goes down as the speed of light goes down. He then argued that if the light is slowed down significantly by passing it through a medium (as in the experiments of Lene Hau where light was passed through a superfluid and slowed to about 17 metres per second), the needed energy would be attainable.[20] However, the physicist J. Richard Gott argues that slowing down light by passing it through a medium cannot be treated as equivalent to lowering the constant c (the speed of light in vacuum) in the equations of General Relativity, saying:[21]
One has to distinguish between the speed of light in empty space, which is a constant, and through any other medium, which can vary enormously. Light travels more slowly through water than through empty space, for example, but this does not mean that you age more slowly while scuba diving or that it is easier to twist space-time underwater. The experiments done so far don't lower the speed of light in empty space; they just lower the speed of light in a medium and should not make it easier to twist space-time. Thus, it should not take any less mass-energy to form a black hole or a time machine of a given size in such a medium.
Later, Mallett abandoned the idea of using slowed light to reduce the energy, writing that, "For a time, I considered the possibility that slowing down light might increase the gravitational frame dragging effect of the ring laser ... Slow light, however, turned out to be helpful for my research."[22]
Finally, Olum and Everett note a theorem proven by Stephen Hawking in a 1992 paper on the Chronology Protection Conjecture,[23] which demonstrated that according to General Relativity it should be impossible to create closed timelike curves in any finite region that satisfies the weak energy condition, meaning that the region contains no exotic matter with negative energy. Mallett's original solution involved a spacetime containing a line source of infinite length, so it did not violate this theorem despite the absence of exotic matter, but Olum and Everett point out that the theorem "would, however, rule out the creation of CTC's in any finite-sized approximation to this spacetime."
Los Carmelitas descalzos obtuvieron un Breve apostólico de Paulo V para edificar conventos de su Orden en cualquier parte de la Cristiandad; fue este el primero que fundaron en la última parte del Monte Quirinal el año de 1606.
La iglesia se fundó en 1605 como una capilla dedicada a san Pablo para los carmelitas descalzos. La propia orden dotó de fondos a la obra del edificio hasta el descubrimiento en las excavaciones de la escultura conocida como el Hermafrodita Borghese. Scipione Borghese se apropió de ella, pero a cambio, y quizá para compensar su pérdida de influencia debido a la muerte de su tío y patrón, financió el resto de la obra de la fachada y prestó a la orden a su arquitecto, Giovanni Battista Soria. Estas concesiones, sin embargo, sólo se llevaron a efecto en 1624, aunque la obra se acabó dos años más tarde.
Después de la victoria católica en la batalla de la Montaña Blanca en 1620, que hizo retroceder la Reforma en Bohemia, la iglesia fue consagrada de nuevo a la Virgen María. Una imagen maltrecha había sido recuperada del ámbito de aquella batalla por Fray Domingo de Jesús María, de dicha Orden, de las ruinas de la casa de campo de un noble cristiano bohemio, a la cual se le atribuyó la victoria, llamándola Santa María de la Victoria. La imagen fue llevada a Roma por Fray Domingo, depositándose en Santa María la Mayor en presencia de Gregorio XV.
El nombre de Santa María de la Victoria, se dio ulteriormente, en conmemoración por haber reconquistado el emperador Fernando I la ciudad de Praga en 1671. Estandartes turcos capturados en el Sitio de Viena de 1683 cuelgan en la iglesia, como parte de este tema victorioso.
La iglesia es la única estructura diseñada y completada por el arquitecto del Barroco temprano, Carlo Maderno, aunque el interior padeció un fuego en 1833 y requirió una restauración. Su fachada, sin embargo, fue erigida por Soria en vida de Maderno (1624-1626), mostrando la inconfundible influencia de la cercana Santa Susanna de Maderno.
Su interior tiene una sola nave, amplia, bajo una bóveda segmentada baja, con tres capillas laterales interconectadas detrás de arcos separados por colosales pilastras corintias con capiteles dorados que apoyan un rico entablamento. Revestimientos de mármol que contrastan entre sí están enriquecidos con ángeles y putti de estuco blanco y dorado en bulto redondo. El interior fue enriquecido progresivamente después de la muerte de Maderno; su bóveda fue pintada al fresco en 1663 con temas triunfales dentro de compartimentos con marcos ficticios: La Virgen María triunfa sobre la Herejía y Caída de los ángeles rebeldes ejecutados por Giovanni Domenico Cerrini.
Sin duda, parte de la fama de este templo se debe a albergar una de las obras maestras del Barroco, la capilla Cornaro, espectacular y teatral espacio presidido por el grupo escultórico que representa el Éxtasis de Santa Teresa, de Gian Lorenzo Bernini, quizá la obra más conocida de este autor en el campo de la escultura. En la capilla situada frente a esta, dedicada a San José, se encuentra un grupo escultórico que representa el tema del Sueño de San José, obra del escultor Domenico Guidi, que se inspira en la obra de Bernini delante de la cual se halla.1
Different cyclotron size: a) Lawrence ́s first one, b) Venezuela First one (courtesy of Dorly Coehlo), c) Fermi National Laboratory at CERN. And size matters, and Cyclotrons win as best hospital candidates due to Reactors are bigger, harder and difficult to be set in a hospital installation. Can you imagine a nuclear reactor inside a health installation? Radiation Protection Program will consume all the budget available. Size, controlled reactions, electrical control, made cyclotrons easy to install, and baby cyclotrons come selfshielded so hospital don ́t need to spend money in a extremely large bunker. Now on, we are going to talk about our first experience with the set up of a baby cyclotron for medical uses inside the first PET installation in Latin America. “Baby” means its acceleration “D” diameters are suitable to be set inside a standard hospital room dimensions, with all its needs to be safetly shielded for production transmision and synthetized for human uses for imaging in Nuclear Medicine PET routine. When we ask why Cyclotrons are better than reactors for radioisotopes production to be used in Medicine, we also have to have in mind that they has: 1. Less radioactive waste 2. Less harmful debris
Different cyclotron size: a) Lawrence ́s first one, b) Venezuela First one (courtesy of Dorly Coehlo), c) Fermi National Laboratory at CERN. And size matters, and Cyclotrons win as best hospital candidates due to Reactors are bigger, harder and difficult to be set in a hospital installation. Can you imagine a nuclear reactor inside a health installation? Radiation Protection Program will consume all the budget available. Size, controlled reactions, electrical control, made cyclotrons easy to install, and baby cyclotrons come selfshielded so hospital don ́t need to spend money in a extremely large bunker. Now on, we are going to talk about our first experience with the set up of a baby cyclotron for medical uses inside the first PET installation in Latin America. “Baby” means its acceleration “D” diameters are suitable to be set inside a standard hospital room dimensions, with all its needs to be safetly shielded for production transmision and synthetized for human uses for imaging in Nuclear Medicine PET routine. When we ask why Cyclotrons are better than reactors for radioisotopes production to be used in Medicine, we also have to have in mind that they has: 1. Less radioactive waste 2. Less harmful debris
I’ve always been fascinated with time. Everything about it interests me. One of the most intriguing aspects of time is that it’s all about motion, in one way or another. The earth rotates on its axis and revolves around the sun. This gives us the hours of the day and the seasons of the year. An analog watch is a model of the movement of the sun, a model loosely based on its moment through the day.
Without the movements of our planet, would time exist? It seems obvious that it would, but we wouldn’t be around to notice it.
For those of us who study astrology, time is extremely important. We give meanings to planets and make note of their movement through our solar system in relation to the earth. Through these symbolic maps, we make predictions of what is coming, or explain what has already happened, as best as we can. In this way, time is much more than just the measurement of movement. It’s a book from which great knowledge may be discerned, depending upon the skill of the observer.
Any discussion of time usually leads to the common, but all-consuming question that so many have asked over the millennia. Is it possible to time travel?
The author, H.G. Wells put forth his idea about what might happen to our planet and eventually to the human race in his novel, “The Time Machine.” He painted a bleak picture of the future, but presented a savior in the form of a man from his own century, rushing to the rescue of humanity.
He wasn’t alone in a dystopian vision of the future, nor in his belief that only someone from our time could save it. This has always been one of the problems for me when reading stories or watching movies about time travel. I have more hope for the future. Every era essentially takes care of itself, although we often can’t begin to imagine how.
The Ethics of Time Travel: Non-Intervention
It’s for this reason that if there is to be any sort of time travel, I believe we should adopt an attitude of non-intervention. What worked for me culturally in 1970 would definitely not work for me in 2016, and trying to impose those archaic ways would get me into trouble. Traveling through time demands an ethical and ideological adherence to observing only, almost an impossible act.
Many science fiction authors focus on moving backwards, into the past, and accidentally changing something that creates a pretty rotten future. Other authors put forth the idea of deliberately trying to change the past and then speculate that no matter how hard they try, time travelers can’t change what has been destined to occur. Shows like the 60s classic, “The Time Tunnel,” tried, every week, to right the wrongs of time, to no avail. Despots still came to power. Ships still sank. Zeppelins were still fated to fiery disasters and the fabric of time remained unchanged.
In science fiction stories where time is successfully altered, the essence of reality is shifted, every now and then for the better, but more often than not in a disastrous manner.
The philosophy of time travel is something that has been pondered for a long time. Time loops, paradoxes, erasing one’s own birth by keeping parents from first kisses, and other truly disturbing thoughts have been worked over by every sort of media. That’s what makes it all so wonderful, daring to ask, “what if?”
Is Time Travel Possible?
I decided to ask my search engine, “Is time travel possible?” I expected to get the old answers, the ones ridiculing the idea and pointing their fingers at me for asking the question in the first place.
Instead, I was stunned to find physicists not only embracing the possibility of time travel, but engaging in experiments that have actually proven Einstein’s theory of relativity and time, notably the flying clocks experiment. Remarkably accurate clocks flying over the earth were found, upon returning to the ground, to be slightly slower than their counterparts here on earth, thus proving Einstein’s theory of general and specific relativity to be correct. The clocks in the jets had essentially travelled forward in time, to the future.
As a non-physicist, discussing all this makes me nervous, but what the heck, it’s all relative anyway. The research on time travel has made great theoretical strides, but from what I’ve been able to glean, we’re not much closer to success in actually breaking through the time barrier. Some of the greatest names in the field, including Dr Stephen Hawking, Dr Ronald Mallett and Dr. Brian Cox, completely believe in time travel.
You’d either have to move close to or faster than the speed of light, or find a wormhole to transport you, but scientists are working on just that.
I urge you to read Hawking’s and Mallett’s ideas on the topic, as they’re fascinating, and to be quite frank, a lot to chew on. I admit that much of it is beyond me, but an image has formed in my mind and I’d like to share with you.
Imagine that you are standing at the bottom of a hill. At the top of the hill is a fence. The fence represents the speed of light. Everything at the bottom of the hill is the present. If we begin to climb the hill, we’re still in our present, but the closer we get to the fence, the more time slows down for us. Once we climb to the top of the hill and are standing next to the fence, time is moving very slowly, much slower than at the bottom. The other side of the fence represents moving faster than the speed of light, and takes us into the past.
Let’s say we managed to jump the fence or find a hole to slip through. If we were able to move far enough beyond the fence, eventually we would be able to turn around and see ourselves at the bottom of the hill before we started upward, because the further away we get from the fence the more we overtake the past. How about traveling to the future? Let’s go back to climbing the hill. If we get to the top and stand next to the fence for an hour, because time moves much more slowly for us near the fence, when we descend back to the base of the hill, many years will have passed, as time moved faster below.
This means we will have traveled into the future. It’s all about speed, light, time and space, and is filled with possibilities.
Time Travel in Folklore
As a metaphysician, everything these esteemed scientists have said fits nicely into my world. It’s something that we believers have discussed for centuries. You may remember the tale of Rip Van Winkle, as well as numerous other stories of supernatural creatures who lure unsuspecting humans into their fairy rings, homes or bowling alleys. In their world, a few hours spent in party mode can equal decades, if not centuries, in our world.
There’s a riveting genius about such stories that almost seems to predict the scientific discoveries that have evolved over the past years. It makes me wonder if there isn’t some truth to those warnings of Fairy Rings and accepting shelter in stone huts on freezing nights on the peat bogs, only to discover that upon returning home, the octogenarian answering the door is one’s own great, great grandson. As mass approaches the speed of light, time slows down. Perhaps these other-worldly beings have a different energy structure than we do and being in their world can draw mere mortals into their space time reality. I’m not saying that such beings actually exist, although it would be silly to deny that they do.
Reverse Time Travel
I’ve had some personal experiences with what I was certain was time travel. Over the years, I’ve thought it all over and I’m not sure that there was any actual travel involved, but I do have a theory as to how one might be able to travel backwards in time, and here it is. According to physicists, it’s impossible to move back in time before a point when the machine designed to facilitate that travel was turned on. That presupposes a mechanical method of time travel, but what if there’s another way?
There is a method of reverse travel that stands out clearly to me. If we could travel faster than the speed of light, we would be able to surpass the present and enter the past, watching it unfold before us, the further we go. If this were possible, we’d be able to choose where we stopped.
There a lot of ifs, ands and buts in all of this, but I’ll ask one question. What is the speed of thought?
Scientists will immediately sit up at their desks and raise their hands, making urgent sounds to be recognized so they can answer. You in the back. Yes you with the slide rule. “The speed of thought must be connected directly to the speed of synaptic responses within the brain and cannot possibly be any faster than those biochemical exchanges will allow.”
My response to this logical answer is this: what if thought, a mystery no matter how you cut it, can move faster than the speed of light? What then? Is it possible to meditate to another time? Food for thought.
When I was in high school, I spent quite a bit of time walking through a graveyard near my school. I wasn’t unnerved and it didn’t seem morbid to me. It was respectful, peaceful and always put things in perspective. There were times when I felt the weight of mortality pressing upon me, especially on gorgeous days, but for the most part, it reminded me that the departed had once been on the planet as we are now and that time overcomes everyone.
As I read the grave markers, it occurred to me that I wanted to do something different. I hatched a plan to have a monument created, one made of something that would last, placed in a relatively conspicuous place. It would say something to the effect of, “Time travelers, please read! My name is Mo and these are the dates of my tenure on this planet. If you are reading this and can move through time, I would appreciate it if you would come visit me. I have some questions I’d like to ask you.”
It just occurs to me that the Internet is pretty much forever and that this is about as conspicuous a venue as there can be. Hmm. Maybe those experiences weren’t just dreams or way too much coffee. Only time will tell.
La Dirección General de Impacto y Riesgo Ambiental de la Secretaría de Medio Ambiente y Recursos Naturales informa que ha recibido la documentación de la firma promovente Más Energía, para el proyecto de la Subestación eléctrica de maniobras Magdalena I (Parque Solar Magdalena I).
El proyecto consiste en la construcción, operación y mantenimiento de una subestación eléctrica de maniobras, dos accesos, y una línea eléctrica de entronque de 400 Kv que se interconectará a una línea de transmisión eléctrica existente de 400 Kv propiedad de la Comisión Federal de Electricidad para desahogar la energía eléctrica que se genera en la planta fotovoltaica parque solar Magdalena I al Sistema Eléctrico Nacional.
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6 Schematic representation of a cyclotron. The distance between the pole pieces of the magnet is shown larger than reality to allow seeing what is inside
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