Particle Accelerators

Edwin J. Ramos Marrero

            Particle Accelerators are machines that uses electromagnetic fields to expulse charged particles to high speeds and to contain them in well defined beams. For the most basic questions in dynamics and structure of matter, space, and time, physicists seek the simplest kinds of interactions at the highest possible energies. These typically involve particle energies of many GeV  and the interactions of the simplest kinds of particles. Particle accelerators have many applications in common use and in experimental and theoretical physics research and also in many technical and industrial fields unrelated to fundamental research. It has been estimated that there are approximately 26,000 accelerators worldwide. Of these, only about 260 are the experimental machines with energies above one GeV, about 11,440 are for radiotherapy, about 10,660 for ion implantation, about 2,340 for industrial processing and research, and about 1,040 for biomedical and other low-energy research.
            There are two basic types of particle accelerators, electrostatic and oscillating field accelerators. Electrostatic accelerators produce a single static high voltage to accelerate charged particles. Although electrostatic accelerators accelerate particles in a straight line, the name linear accelerator is more often used with accelerators that produce oscillating electric fields instead of static ones, this is why many accelerators are not named linear accelerators, instead electrostatic accelerators.
            Oscillating field particle accelerators produce an oscillating high voltage produced by an electrical discharge in order to accelerate particles to higher energies based on techniques involving more than one lower, but oscillating, high voltage sources. The electrodes can either be arranged to accelerate particles in a line or in a circle, depending if the particles are exposed to a magnetic field while they are accelerated, causing their path to arc.
            Many experimental particle accelerators, especially the Large Hadron Collider, have caused worries among some physicists about the risk involved by such machines not only to the scientists involved but to the whole Earth. Some mathematical theories show the possibility that a high-power particle accelerator could cause the formation of small black holes. Most physicists, however, agree that these small black holes, if produced, would be a small threat as they would either dissipate into Hawking radiation or grow too slowly to be any kind of reasonable danger. Many of today's discoveries, like the electron for example, where found through the use of a cathode ray tube, one kind of particle accelerator. Also tomorrow's possible discoveries like the Higgs&Boson particle, that makes energy acquire mass and vice-versa, would probably be thanks to this machines. If discovered, it could provide the key to a much greater understanding of the whole physical world as we know it.
            A particle accelerator may seem to some to be a primitive tool, by the fact that it's a device used since the early 20th century. Despite this fact, the scientific knowledge gained from such devices, is huge and will likely continue to be, as particle accelerators become more and more powerful.

Black Holes 

Leonardo A Pierantoni Arroyo

What is a black hole?

A black hole is an object that has a small volume with sufficient mass to create a gravitational force so strong that even light itself can’t escape it. The English geologist and philosopher John Michell with the French mathematician and astronomer Pierre-Simon Laplace argued that if an object were either extremely massive or extremely small, it might not be possible to escape its own gravity.

How are black holes are created?

Black holes are born when an object becomes incapable to resist the compressing force of its own gravity. For example, objects like our planet Earth and the Sun will never become black holes. Their gravity is incapable to overwhelm the atomic and nuclear forces of their cores. But, in more colossal objects gravity eventually wins.

Massive black holes are born with an explosion. They form when a very colossal star (at least 25 times bigger than the Sun) runs out of energy. The star explodes as a supernova. The only thing left after the bang is a black hole, usually a couple times heavier than our Sun. 

The large hardon collider. 

A 17-mile particle acceleration located in the CERN laboratory in Switzerland that might create mini black holes.

How do black holes increase size?

They grow in mass when they catch material that is within their reach. Once something enters the black hole it can’t escape. But regardless their reputation they can’t catch objects that are far away. They only swallow objects that are very close to it. They usually suck gas and dust. 

A black hole pulling gas, dust and light with his gravitational force.

Do black holes follow the gravitational laws?

Despite some people idea that black holes doesn’t obey the laws of gravity, they actually follow all laws of gravity.  Because of the laws of gravity is that black holes have all the incredible properties. Black holes are a direct consequence of gravity. Isaac Newton and Albert Einstein agreed that the most influential force in a black hole is gravity.

What happens when black holes collide?

Black holes can collide but, we never had experience of seen it. It’s the same as with all the other things they cannot escape each other gravity and can become a bigger hole. But’s like I said it’s all theoretical, because it has never been seen by us. There are known black holes in other galaxies in which two super massive black holes move dangerously close to each other. With time it’s supposed that gravity pull them together and collide. If two black holes collide they will form gravitational waves according to the fundamental prediction of Einstein theory of general relativity.

What inside a black hole? 

No one can really know what lies inside a black hole. Because nothing can’t escape his gravitational pull even if some put an explorer inside it can never communicate with us. The gravitational force will not let us hear or see the explorer it will suck the sound waves and light once it enters the black hole.

Current theories anticipate that all the matter in a black hole is accumulated in the center. But we don’t know how it works. The understanding of black holes require the combination of the theory of gravity and the study of matter in the smallest form called quantum mechanics. This combination is called quantum gravity. Future studies in quantum gravity might provide us an answer on the center of black holes

Do black holes live forever? 

It was tought that black holes couldn’t be destroyed. But now we know that black holes actually evaporate slowly handing back their energy to the universe. Thanks to Stephen Hawking and the law of quantum mechanics we know this today. Like I said before the quantum theory explains the behavior of matter in the smallest scales. It predicts that tiny particles are contiounisly created and destroyed in sub-atomic scale. Particles are destroyed until the black hole mass is decreased. But, they need an immense amount of time to loose their mass unlikely for us to see it in a lifetime.

Some theories say that a black hole is a shortcut between two distance points in the curved space-time of the Universe.

Black holes are on of the most important unsolved problems in physics.

Large Hadron Collider

 

Steven Santos

 

The Large Hadron Collider, commonly referred to as “LHC”, is a massive particle accelerator situated in Europe. It is located in a tunnel below the Swiss and French border in a city called Geneva. The Hadron Collider was first finished and used in 2009. It has been used in various experiments since then, helping scientists to better understand questions, like how the universe behaved after the Big Bang and other important issues related to physics. Many have heard of the LHC in the news, during conversations, or on the internet, but what exactly does it do? What is its purpose? How does it work?
 

To understand how LHC works, we must first understand what “hadrons” are. Hadrons are composite particles made of up quarks, which are the building blocks of matter. As the name suggests, the LHC accelerates these particles through beams in the machine where they collide with other particles. The beams are guided by close to 9,300 magnets around a 27 kilometer loop under Geneva, Switzerland. At four locations in this loop (or circle) there are superconducting radio frequency cavities which accelerate the particles:
 

“Just like pushing a child’s swing, these RF cavities give the particles a push each time they pass, steadily increasing the energy of the particles prior to collision” (STFC).
 

The magnets are bathed in “supercold” liquid helium. 

Such a massive machine requiring the attention of dozens of engineers and scientists must have an important purpose.
 

“The LHC was built to help scientists to answer key unresolved questions in particle physics. The unprecedented energy it achieves may even reveal some unexpected results that no one has ever thought of!” (CERN).
 

Many questions have been answered, or will be answered through the use of the LHC. These include the origin of mass and why some particles have no mass, the detection dark matter and how it makes 96% of the universe, why is there an absence of anti-matter, how the universe behaved seconds after the big bang, and the existence of hidden dimensions. The experiments have names like ATLAS and ALICE to classify them. The LHC truly is an amazing machine. 

Apart from the experiments, the LHC specifications are also astonishing. The LHC, to start off, is the largest machine in the world. When the LHC is at full power the particles it accelerates travel at 99.9% the speed of light. The beams are set to travel in a vacuum which is emptier than space to avoid particle collision with gas particles. The LHC is capable of extreme temperatures. During particle collision, the temperatures rise to 100,000 times hotter than the heart of the sun, in a tiny space, while the supercold helium cools the LHC to a temperature cooler than space. The LHC also has the most powerful supercomputer in the world capable of connecting a network of scientists all over the world. The remarkable facts about this machine go on and on. 

The Large Hadron Collider is tremendous feat by the scientific world. The experiments it will conduct will change the way scientists view the universe. During the next fifteen years (its remaining lifespan) it will be interesting to see what information these experiments yield and how it affects the human race.

Works Cited:

Fact and Figures. European Organization for National Research (CERN). Copyright CERN 2008. http://public.web.cern.ch/public/en/lhc/Facts-en.html. 26/December/2010.
 

Welcome to the Large Hadron Collider. STFC Large Hadron Collider. 2010 Science and Technology Facilities Council - All Rights Reserved. http://www.lhc.ac.uk/default.aspx. 26/December/2010.

Possible Uses of Antimatter

 

Alex G. Miranda

    Antimatter’s existence has been publicly suggested in theories concerning the science of physics since the late XIX century. It was first called ‘negative matter’, and it wasn’t until 1898 that the scientist Arthur Schuster named it antimatter, in his book titled Nature. The existence of antimatter responds to the principle of symmetry of the universe, to which it calls for a dual nature of everything, and that everything is matter, including the forces surrounding it. Positrons, antiprotons, and neutrinos are the corresponding antimatter particles for electrons, protons and neutrons respectively. In Earth’s nature, antimatter is not present, but it is believed that there are places in universe that are completely composed of antimatter. Theoretically, if the particles of antimatter were to be mixed, the reaction would cause the particles to annihilate each other and in return it would produce an intense explosion of gamma rays. Recently, at the European Organization for Nuclear Research’s (CERN) in its ‘Large Hadron Collider’, which is located in the Franco-Swiss border, proton-proton collisions have generated anti-hydrogen particles that were stable enough to get caught to further studies of this kind of particle, which are unavailable in our environment.

    Because of the lack of high-energy sources and the high dependence on oil in most of the countries in the world, including the United States, the human race is currently incapable of producing significant quantities of antimatter, which would require high imputes of electricity. Nevertheless, there are two ways that could change the scenario of antimatter shortage: 1- relying renewable energy sources such as Ocean-Thermal (OTEC) power plants and, 2- improvements in aerospace engineering that could lead to the establishment of particle colliders of constant operation in inner space. An OTEC power plant is a renewable-energy suggested technology of energy generation based on the difference in the temperature of surface and deep oceanic currents. A known ideal place for such a plant is at Puerto Rico’s southeast coast, specifically in Punta Tuna, Maunabo, which is two miles from the coast in where the currents of the Atlantic Ocean, both hot and cold, converge.

    Considerable quantities of antimatter could grant humankind with unexpected benefits, but also dangers. New propulsion technologies could be developed having antimatter as fuel. It is believed that one single kilogram of antimatter could produce such a explosion bigger than the Tsar Bomba, the biggest nuclear bomb to be ever developed in the world by the former Soviet Union. A relative small quantity of antimatter could then give high velocity propulsion to a space vehicle, making the humankind capable of reaching more distant places faster than now, with conventional fuels. Another possible use could be energy generation itself. If antimatter could be produced in space laboratories without consuming the energy from planet Earth, that antimatter could be used back in our planet in the same way as nuclear reactors or in new, safer technologies of energy generation that could have antimatter as fuel.

    Because of its nature, antimatter itself could be used as a weapon due to its explosive behavior when mixed with conventional matter. This is the biggest danger of a possible antimatter mass-production. As we stated before, it is believed that a single kilogram of antimatter could produce a massive explosion if mixed with a single kilogram of conventional matter and the effects of such an explosion would be more lethal than an explosion made by a nuclear bomb. Although both of the explosions emit gamma radiation, the nuclear explosion partially releases it (exclusively at the beginning of the detonation) while the antimatter explosion literally consumes matter when emitting gamma radiation along the whole detonation.

    Although there are always dangers, I believe that there are also huge benefits in the search of new and better mechanisms of antimatter mass-production. Further antimatter interest in the scientific community could trigger governments’ sponsored efforts in the development of new technologies of energy generation, superconductivity, extremely high-energy devices and even new fuels that could lead to high-speed space vehicles in the near future. I just hope that after the 20th century aftermath, the civilization has evolved enough to deal with such knowledge and that they will not use it in warfare or similar activities that could lead to mass destruction. 
                               

The danger of ultraviolet rays

 

Efraín Soto Valentín

My parents used to tell me not to take too much sun between 11:00 and 3:00 pm and I asked them why, but they don’t have the right answer to answer that question so I navigate through internet to find some answers. The solar rays are a lot of electromagnetic radiations emitted by the Sun. The sun emitted a lot of different rays like infrared rays and ultraviolet rays. These rays are divided depending on the danger they cause to the human skin. There are different types of rays but the most dangerous rays are the ultraviolet rays. In the last summer I went too many times to the beach. The first time I spent just four hours in the sun from 10:00pm to 2:00pm and I get burn. My skin was black and I can’t sleep in the night because my skin hurts and I have too much heat. I get black because I forgot to put in my skin some solar spray.  During this hours the sun emitted more ultraviolet ray than other hours, that is why you have to be careful to not to take too much sun during this hour or just put out some sun spray to protect your skin.

The ultraviolet rays have good uses in the field of science.  One of the applications is that the scientist uses the ultraviolet rays together with the infrared rays, to eliminate any kind of bacteria or virus with more effective results than the chemical products.  Another application is the use of fluorescent lamps to attract flies and other flying insects to the ultraviolet light produced by the lamp and when they get closer the lamp makes an electric current that kill the insects. These are the good applications of the ultraviolet rays, but there produce more danger than you think that it can help. The ultraviolet rays cause danger to the human skin if you spend too much time in the sun, like me. The different types of damage the ultraviolet rays produce are skin cancer, irritation, wrinkles, spots and loss of elasticity.

 My teacher from high school told me that the ultraviolet rays are mutagenic; this means that those rays can produce mutations. Also she told me that only the cumulus clouds block these ultraviolet rays, but we have to take care because some clouds act like mirror and increase the intensity of the ultraviolet rays and cause more danger. So the ultraviolet rays are good for different experiments and applications but there are bad for the human skin. We have to protect our skin form this radiation even if the day is cloudy we have to protect the skin. So my advice to all these people that like to go to the beach during summer and spent a lot of time in the sun, that bring in the backpack some sun block and put it in the skin every hour to protect your skin and to prevent some danger in the future. 

 Women behind Physics

 

Suasy Chanielle Acevedo Muñiz

Physics is the scientific study of matter and energy and how they interact with each other.[1] The scientists who study physics are physicist. When we talk about physics we think in Albert Einstein, Newton, Kepler, Cristian Huygens, Copérnico, Coulomb, Planck,  Bohr,  or Galileo. But ...why we do not talk about women?

Many people think only man can be an extraordinary scientist. One example of this thinking is when Darwin said in his book: "man has ultimately become superior to woman". [2] But behind physics are countless women who have contributed greatly in this science so complicate.

 One of them is Marie Curie. In 1903 Marie received the Nobel Prize in Physics, shared with her husband.[3]  Curie was the first woman admitted as professor at the Sorbonne University. She retained her enthusiasm for science (physics and chemistry) throughout her life and did a lot of things to establish a radioactivity laboratory in her native city.

But she is not the only one. María Mitchell was America's first woman astronomer. Also Mitchell was the first woman to join the American Academy of Arts and Science. For her merits she had a tablet with her name in the New York University Hall of Fame. Also, her name was carved in a frieze at the Boston Public Library and she was inducted into the National Women's Hall of Fame.

Another example of extraordinary woman in physics is Emilie de Breteuil. She was a woman of high society and a great physicist. Emilie worked at investigation about fire. Emilie de Bruteuil argued that light and heat have the same cause or are the same type of movement. And then she found that rays of different colors do not release the same degree of heat.

In addition, we can talk about Laura Bassi. She was an Italian Newtonian physicist. Bassi was one of first scholars to teach Newtonian natural philosophy in Italy. She published 28 papers on physics and hydraulics. Laura carried out experiments in all aspects of physics.

Also, Lise Meitner is another example of woman behind physics . Lise collaborate with Otto Hahn in the studied of radioactivity. Like Marie Curie, she was the first woman admitted as professor in Germany.

Frank Wilczek said “ In physics, you don't have to go around making trouble for yourself - nature does it for you”. We know, physics is complicate and sometimes require effort, but Marie Curie, Emilie de Breteuil, Laura Bassi, Lise Meitner, María Mitchell and other extraordinary physicist are the example that physics are not impossible. If these women break barriers in society and prove is not impossible, why we cannot do it?  Many people can have a wrong think of that only men can be outstanding physicist but women like those mentioned in this article demonstrate physics is not only for men. They have inspired me to continue efforts to understand the physics and get a good grade in the course.

Never underestimate the power of a woman behind the science!

[1] http://physics.about.com/od/physics101thebasics/f/WhatisPhysics.htm
[2] Darwin, Descent of Man 2, pp.327-328
[3] http://www.aip.org/history/curie/