Four... three... two... one... fire!

The death star is a tremendous weapon good-sized moon. Shooting point-blank at defenseless planet Alderaan, the home of Princess Leia, the death Star completely destroys it. Planet disappears in the flame of a Titanic explosion, scattering debris across the Solar system. Billion shower simultaneously screams in agony, causing the indignation of Power, which can be felt anywhere in the galaxy.

But is it really possible weapons, like the death Star from the epic Star wars? Is it possible to organize and direct the battery laser guns to evaporate the whole planet? And what about the famous lightsabers possessed by Luke Skywalker and Darth Vader, representing a ray of light, but can easily be cut armored steel? Will the beam rifle, like phasers in the TV series "Star trek", suitable weapon for the future generations of the law-enforcers and soldiers?

New, original and amazing special effects "Star wars" made an irresistible impression on millions of viewers, but the critics formed a different opinion. Some of them claimed that Yes, of course, the filmmakers tried earnestly to entertain the viewer, but in fact, such things are impossible. Critics kept repeating the mantra: beam guns the size of the moon, able to post on small slices whole planet is something unheard of; impossible and swords of a sudden hardening of the light beam. All this is too much even for the far-distant galaxy. This time George Lucas, a recognized master of special effects, skidded a bit.

Maybe it's hard to believe, but in light beam can "push" unlimited energy; there are no physical limitations. The creation of the death Star or light sword is not contrary to any law of physics. Moreover, the beams of gamma radiation that can blow up the planet, actually exist in nature. Titanic burst of radiation generated far and mysterious source of gamma-ray bursts, are able to arrange in deep space explosion, which is second in power only to the Big Bang. Any planet that would get to be in the sight of this "gun", it would indeed be fried or torn to pieces.
Beam weapons in history

Dream to curb energy radiation is actually not new; it has roots in ancient religion and mythology. The Greek God Zeus is famous shot of the mortals of lightning. Northern God Thor possessed magical hammer, Millirem able to hurl lightning, and the Hindu God Indra fired energy beam from a magic spear.

The idea of the beam as a practical weapon for the first time appeared in the works of the great Greek mathematician Archimedes, perhaps the greatest scientist of antiquity, which managed to develop his own version of primitive differential calculus in two thousand years before Newton and Leibniz. It is believed that in the legendary battle 214 BC against the troops of the Roman General of Marcellus during the Second Punic war Archimedes, helping to protect against Syracuse Kingdom, made a huge battery of solar reflectors, focused rays of the sun on the sails of enemy ships and thus set them on fire. (Scientists are still arguing whether this beam weapons could work; several groups of scientists have tried, with varying results, reproduce this achievement.)

Ray guns broke into the pages of science fiction in 1889 with the classic novel by H. G. wells ' war of the worlds". In this novel from Mars destroyed the whole city, directing to the rays of the heat energy from guns installed on their tripods. During the Second world war the Nazis[3], are always ready to explore and adopt the latest technology, to use them for the conquest of the world, also experimented with different types of beam guns, including acoustic devices using parabolic mirrors focused powerful sound rays.

Weapons, representing a focused light beam[4], has captured the imagination of the audience after the film "Goldfinger" James bond; it was the first Hollywood movie, where the featured laser. (The legendary British spy was tied to a metal table, and a powerful laser beam slowly approached him, gradually melting table between his legs and threatening to cut hero in half.)

Originally physics just laughed at the idea beam guns, expressed in the novel by H. G. wells, such as guns broke the known laws of optics. According to Maxwell's equations, the light that we see around, decoherence (that is a mixture of waves with different frequencies and phases) and quickly dissipated. It was once thought that a coherent, focused, homogeneous beam of light such as the laser beam, - it is impossible to get.
The quantum revolution

Everything changed after the advent of quantum theory. Already in the beginning of XX century it became clear that, although Newton's laws of motion and Maxwell's equations successfully describe the motion of the planets and the behavior of light, there is a whole class of phenomena that they can never be explained. Sadly, they didn't say anything about why the materials conduct electricity, why metals melt at certain temperatures, why fumes when heated emit light, why certain substances at low temperatures find superconductivity. To answer any of these questions, you need to understand the internal dynamics of atoms. Overdue revolution. Newtonian physics after 250 years of sovereignty was waiting for its overthrow; at the same time the collapse of the old idol had to proclaim the beginning of the birth pangs of the new physics.

In 1900 Max Planck in Germany suggested that energy is not continuous, as did Newton, but exists in the form of small discrete "portions", called "quanta". Then in 1905, Einstein postulated that light too is made of tiny discrete packets, or quanta), later called photons. Using this simple but powerful idea, Einstein was able to explain the photoelectric effect, namely why the metals under irradiation with light emit electrons. Today the photoelectric effect and the photon serve as the basis for television, lasers, solar cells and a significant part of modern electronics. (Einsteinova theory of photon was so revolutionary that even Max Planck, usually hotly were in support of Einstein, at first could not believe it. Planck wrote about Einstein: "the fact that sometimes he misses... as, for example, we have had with the hypothesis of light quanta, cannot, in good conscience, to put him in the wine.")

Then in 1913, the Danish physicist Niels Bohr has given us an entirely new picture of the atom, the atom at Bora resembled a miniature solar system. But, unlike the present Solar system electrons in an atom can move around the nucleus only within discrete orbits or shells. When an electron jumps from one shell to another, closer to the core and with less energy, it emits a photon of energy. Conversely, when an electron absorbs a photon with a certain energy, he moves higher on the shell, located further from the nucleus and with more energy.

In 1925, with the advent of quantum mechanics and revolutionary works of Erwin Schrodinger, Werner Heisenberg, and many others, was born almost complete theory of the atom. According to the quantum theory of the electron was a particle, but also had the associated wave, giving him both the properties of particles and waves. Wave this was subordinated to the so-called wave Schrodinger equation, allowing to calculate the properties of atoms, including all Bohr postulated "jumps" of electrons.

Until 1925 the atoms was considered mysterious objects; many, like the philosopher Ernst Mahu, did not believe in their existence. After 1925 the person had a possibility not only to look into the dynamics of the atom, but also quite reliably predict its properties. How amazingly, this meant that, having a sufficiently powerful computer, you can display the properties of chemical elements directly from the laws of quantum theory. Just as Newtonian physics if there are enough computers would allow the scientists to calculate the movement of all celestial bodies of the universe, quantum physics, according to scientists, gave the principal possibility to calculate all the properties of chemical elements in the Universe. In addition, having a sufficiently powerful computer, you could be a complete wave function of the human being.
Masers and lasers

In 1953, Professor Charles Townes from the University of California at Berkeley have managed, together with colleagues, to get the first beam of coherent radiation, namely microwaves. A device called a maser (maser - by the first letters of the phrase "microwave amplification through stimulated emission of radiation", i.e. the enhancement of microwaves through the stimulation of radiation".) Later, in 1964, Townes together with Russian physicists Nikolai Basov and Alexander Prokhorov was awarded the Nobel prize. Soon the results of the scientists were extended to visible light. Thus was born the laser. (But Phaser is a fantastic device, was known for the TV series "Star trek".)

The basis of the laserbut serves a special environment that will transmit the laser beam; this can be a special gas, crystal, or diode. Then you need to upload this Wednesday the energy from outside - from electricity, radio waves, light or chemical reactions. The sudden influx of energy excites the atoms of the medium, causing electrons to absorb energy and jump on more high-energy external electron shell.

In such an excited, inflated the state of the environment becomes unstable. If you then send it through a beam of light, the photon beam, colliding with atoms, will cause sudden stalling of electrons at a lower orbit and the release of additional photons. These photons, in turn, will cause an even greater number of electrons to emit photons - and soon will start a chain reaction collapse of the atoms to the unexcited state with nearly simultaneous release of enormous quantity of photons - trillions and trillions of them - all in the same beam. The fundamental feature of this process is that some substances for avalanche release of all photons vibrate in unison, i.e. coherent.

(Imagine ranked dominoes. In the low-energy state of each tile is lying flat on the table. In a high-energy, inflated condition knuckle stand vertically, like a pumped up the atoms of the medium. Pushing one Domino, you can cause sudden simultaneous release of all of this energy, just as it happens at the birth of the laser beam.)

The laser can operate only some of the material; it means that only in specific substances in the collision of a photon with an excited atom radiates the photon coherent first. This property of a substance leads to the fact that all photons in rojdayutsya thread vibrate in unison, creating a fine laser beam. (Contrary to popular legend the laser beam is not always remains the same thin, as in the beginning. For example, the laser beam, released in the moon, will be on the road gradually expanded and will give on the surface of the moon spot size of several kilometers.)

Simple gas laser is a tube with a mixture of helium and neon. When through the tube miss electricity, atoms absorb energy and excited. Then, if there is a sudden release of all stored gas energy, born beam of coherent light. This beam is amplified using two mirrors installed at both ends of the tube, so the beam is reflected from them in turn, and tosses the tube from side to side. One of the mirrors is completely opaque, but another skips a small fraction of incident light, releasing so the beam out.

Today, lasers can be found everywhere - in the cash register grocery store, and in optical fiber cable that provides you with Internet access and a laser printer, or CD player, and a modern computer. Lasers are used in eye surgery, for removing tattoos, and even in beauty salons. In 2004, were sold in the world of lasers more than 5,4 billion.
Types of lasers and their features

New lasers are now opening almost every day; as a rule, we are talking about the discovery of new substances, capable to work in the laser, or the invention of a new method of pumping energy into the working body.

The question is, whether these are good technologies to create beam guns or lightsabers? Is it possible to build a laser, large enough to provide power of the death Star? Today there is a staggering variety of lasers that can be classified by material of a working body and the method of injection of energy (this may be electricity, powerful light beam, even chemical explosion). We list several types of lasers.

• Gas lasers. This category includes extremely common helium-neon lasers, giving very familiar red ray. Inflate their using radio waves or electricity. Helium-neon lasers are not very thick. But gas carbon dioxide laser can be used at blasting, cutting and melting of metals in heavy industry; they can provide extremely powerful and completely invisible beam;

• Chemical lasers. These powerful lasers dawn passage from chemical reactions - for example, burning of ethylene and nitrogen TRIFLUORIDE NF3. Such lasers powerful enough to find application in the military field. U.S. chemical principle of pump is used in air and ground combat lasers capable of beam power in millions of watts and intended for churning in flight shorter-range missiles.

• Excimer lasers. These lasers get energy from a chemical reaction, which usually involved inert gas (i.e. argon, krypton or xenon) and some fluoride or chloride. They provide UV light and can be used in electronic industry for etching CROs is arable, of transistors on semiconductor chips, as well as in eye surgery to perform delicate operations on Lasik technology.

• Semiconductor lasers. Diodes, which we widely use in all kinds of electronic devices, can give a powerful laser beams, which are used in industry for cutting and welding. These semiconductor lasers working in the cash register, reading barcodes with selected items.

• Dye lasers. In these lasers as a working body uses organic paint. They are extremely useful in obtaining ultra short pulses of light, which often have a duration of about a trillionth of a second.
Lasers and beam guns?

Given the huge variety of commercial lasers and power lasers military, it's hard not to wonder: why don't we ray guns and cannons, suitable for use on the battlefield? In the science fiction movies beam rifles and pistols of different varieties, as a rule, are the most common and familiar weapons. Why don't we work to create such weapons?

The simple answer to this question lies in our lack of portable energy sources sufficient power. This is not a trifle. For beam weapons would miniature battery the size of a palm, but relevant with the enormous power plant. Currently, the only way to get and use the power of large power stations-build one. And the smallest military unit, capable of serving as a conduit for such energy - miniature hydrogen bomb, which, unfortunately, can destroy not only objective, but also of you.

There is the problem of stability of radiating matter, or working fluid. Theoretically, the amount of energy that can be injected into the manhole er, no limits. But the problem is that the working body handheld laser gun would be unstable. Crystalline lasers, for example, overheat and burst, if you upload them too much energy. Therefore, to create an extremely powerful laser is such, that could evaporate the subject or neutralize the enemy - may need to use the energy of the explosion. In this case, of course, on the stability of a working body can not think, because our laser is disposable.

Problems creating portable energy sources and stable emitting materials make the existence of ray guns impossible with the current level of technology. In General, radiation gun can be created only if you fail to her the cable from the power source. Possibly with the use of nanotechnology will we ever create a miniature battery capable of storing or to generate energy, which would be enough to create powerful bursts is a necessary attribute handheld laser weapons. Now, as we have seen, nanotechnology are in their infancy. Yes, scientists have managed to create at the atomic level some devices - very witty, but completely impractical, such as nuclear scores or nuclear guitar. But it may happen that in this or, say, in the next century nanotechnology will really give us a miniature batteries to store fantastic amounts of energy.

With light swords the same problem. After the release in 1970 film "Star wars" toy lightsabers immediately gained incredible popularity among the boys. Many critics felt it my duty to indicate that the reality of such devices is not possible. First, the light cannot make a firm. Light moves at the speed of light, so otvetiti it is impossible. Secondly, a ray of light cannot be dropped sharply in space, as do lightsabers in "Star wars". A beam of light is impossible to stop, he always is in motion; real lightsaber would have gone far in the sky.

Actually there is a way to make a kind of lightsaber from plasma, or superheated ionized gas. If the plasma is warm enough, it will light up in the dark and cutting steel, by the way, also. Plasma lightsaber would be a fine telescopic tube that extends from the arm.

The tube of the arm comes hot plasma, which then comes out through small openings along the entire length of the "blade". Plasma, lifting of the arms along the blade and walking out, forms long glowing cylinder superheated gas, hot enough to melt steel. This device is sometimes called a plasma torch.

Thus, we can create high-energy device that resembles a lightsaber. But here, as in the situation with ray guns have to first acquire a powerful portable battery. So or you are using nanotechnology will create a miniature battery that can provide your lightsaber communitiesthe principal amount of energy, or you will have to connect it to a power source using a long cable.

So, while ray guns and lightsabers can in some form to create and today, hand weapons, which we see in science fiction movies, at the modern level of technology is impossible. But later in the century, or maybe in the next development of materials science and nanotechnology may lead to the creation of a particular type of radiation weapons that allow us to identify it as the inability of the I class.
Energy for the death Star

To build a death Star - laser cannon, capable of destroying an entire planet and bring terror to the galaxy, as shown in "Star wars", you must create the most powerful laser, imaginable. Currently, the most powerful, probably, on the Ground lasers are used to obtain temperature, which in nature can be found only in the cores of stars. Perhaps these lasers and based on them the synthesis reactors will ever help us on Earth to curb stellar energy.

In synthesis reactors scientists are trying to reproduce the processes that occur in space when forming stars. At first star appears as a huge ball of unregistered hydrogen. Then the gravitational force compresses the gas and thus heat; gradually the internal temperature reaches astronomical values. For example, deep in the heart of a star, the temperature may rise to 50 to 100 million degrees. There is enough hot to hydrogen nuclei began to stick to each other; this raises a helium nucleus and energy is released. In the process of synthesis of helium from hydrogen small part of the mass is converted into energy according to the famous Einstein formula E = mc2. This is the source from which the star draws its energy.

At present, scientists are trying to harness the energy of nuclear synthesis in two ways. Both turned out to be much more complex to implement than previously thought.
Inertial confinement for laser fusion

The first method is based on the so-called inertial confinement. Using the most powerful in the world of lasers in the laboratory artificially created a piece of the sun. Solid-state laser using a neodymium glass is ideal for playback of high temperatures, which can only be detected in the cores of stars. The experiment uses a laser system the size of good works; a battery of lasers included in such a system, shoots in a long tunnel, a series of parallel rays. Then these powerful laser beams are reflected from a system of small mirrors mounted around a spherical volume. Mirrors precisely focus all laser beams, directing them to the tiny ball of hydrogen-enriched substances (such as lithium deuteride targets, the active ingredient of a hydrogen bomb). Usually scientists use a ball the size of a pinhead and weighing only about 10 mg.

Laser flash instantly heats the surface of the ball, causing evaporation of the upper layer of the substance and the sharp compression of the ball. It "collapses", and the resulting shock wave reaches its very centre and causes the temperature inside the ball to climb up to millions of degrees - the level required for nuclear fusion of hydrogen to form helium nuclei. Temperature and pressure reached such astronomical values that runs the Lawson criterion, the same one that is in the cores of stars and in the explosions of hydrogen bombs. (Criterion Lawson says that to start thermonuclear reactions in the hydrogen bomb, in a star or in the reactor must be achieved certain levels of temperature, density and retention time.)

In the process of fusion with inertial confinement released a huge amount of energy, including in the form of neutrons. (Temperature lithium deuteride targets may reach 100 million degrees Celsius, and the density - twentyfold density of lead.) There is a surge of neutron radiation from the ball. Neutrons penetrate into spherical "blanket" of matter surrounding the camera reactor and heat it. Then the resulting heat is used to boil water, and couples can already be used to drive a turbine and generate electricity.

The problem, however, is to focus high-energy rays and spread their radiation on the surface of a tiny ball. The first serious attempt laser fusion was "Shiva" - dvadcatiiy laser system, built at the Lawrence Livermore national laboratory behalf of the Lawrence (LLNL) and launched in 1978 (Shiva - many-handed goddess of the Hindu Pantheon, which resembles a multi-beam laser system.) The results of the work of the laser system "Shiva" was discouraging; however, with its help was able to prove that laser thermonuclear synthesis technically possible. Later replaced "Shiva" came laser "Nova", ten times superior to "Shiva" power. But "Nova" was not able to provide hydrogen ball tribute to the ignition. Be that as it may, both paved the way for the planned research on a new installation, the National Ignition Facility (NIF), the construction of which began at LLNL in 1997

It is expected that the work of the NIF will begin in 2009, This monstrous machine represents a battery of 192 lasers that issue in a short pulse of the enormous capacity of 700 trillion watt (total output of about 70 0000 large nuclear power units). This is the newest laser system designed specifically for full thermonuclear burning saturated with hydrogen balls. (Another criticism is its apparent military value because such a system is able to simulate the process of detonation of the hydrogen bomb; perhaps it will help to create a nuclear weapon new type of bomb, based solely on the process of synthesis, for detonation which is no longer needed uranium or plutonium nuclear charge.)

But even the system NIF intended to support the process of nuclear fusion and incorporating the most powerful in the world of lasers, can't even remotely compare to the power of the subversive power of the death Star, known to us from "Star wars". To create these devices we have to look for other sources of energy.
Magnetic confinement for fusion

The second method, which in principle could be used by scientists to ensure Races death of energy, known as magnetic confinement - the process by which a hot hydrogen plasma is held in place by means of magnetic field.

This method can serve as a prototype for the first commercial fusion reactors. Currently, the most advanced project of this type - international thermonuclear experimental reactor (ITER, the International Thermonuclear Experimental Reactor). In 2006, several countries (including the European Union, the United States, China, Japan, Korea, Russia and India) decided to build a reactor in Cadarache in southern France. In it, the hydrogen has to warm up to 100 million degrees Celsius. It is not excluded that ITER will be the first fusion reactor in history, that will produce more energy than it consumes. It is designed for production of 500 MW of capacity for 500 C (the current record is 16 MW for one second). It is planned that the first plasma will be achieved in ITER by 2016, and a fully install will come on line in 2022 Project is worth us $ 12 billion. and is the third value of the research project in history (after the Manhattan project and the International space station).

With mind installation ITER is like a big donut, braided with huge rings electrical winding; inside the bagel circulates hydrogen. Winding cooled to the status of superconductivity, and then injected into it huge amount of power, creating a magnetic field, which holds the plasma inside the bagel. When electric current is passed directly through the bagel, gas inside his star is heated to temperatures.

The reason why scientists are so interested in the ITER project, is simple: in the future it promises the creation of cheap energy sources. Fuel for thermonuclear reactors is normal sea water rich in hydrogen. Turns out, at least on paper that nuclear fusion can provide us with cheap and inexhaustible source of energy.

So why do we still don't have fusion reactors? Why for decades - since that moment as in the 1950s was a scheme of the process - we cannot achieve real results? The problem is that evenly compressing the hydrogen fuel is incredibly difficult. In the cores of stars gravity causes the hydrogen to the ideal spherical shape, resulting in a heated gas is clean and evenly.

Laser thermonuclear synthesis in the installation NIF requires that the laser beams, flammable surface hydrogen ball, were equal, and to achieve this extremely difficult. In installations with magnetic retention important role is played by the fact that the magnetic field has a North and South pole; the result is uniformly compressed gas proper sphere is extremely difficult.

The best we can create is the magnetic field in the shape of a donut. But the process of gas compression reminds clenching in the hands of the balloon. Every time you squeeze the ball from one end, the air pulls it elsewhere. Squeeze the ball simultaneously and evenly in all directions - a difficult task. Hot gas, as a rule, leaks from magnetic bottles; sooner or later he reaches the walls of the reactor, and the process of nuclear fusion stops. That is why it is so difficult to compress the hydrogen enough to keep him compressed even for a second.

Unlike modern nuclear stations, where splitting atoms, a fusion reactor would produce a large quantity of nuclear waste. (Each of the traditional nuclear reactors produce 30 tons of highly dangerous nuclear waste. In contrast, nuclear waste thermonuclear reactor for the most part will be radioactive steel, which will remain after disassembly.)

We should not hope that in the near future thermonuclear fusion will solve the energy problems of the Earth. The Frenchman Pierre-Gilles de Gennes, Nobel laureate in physics, said: "we say We put the Sun in the mailbox. Beautiful idea. The problem is that we don't know how to make this box." But the researchers hope that, if all goes well, forty years later ITER will help scientists to pave the way for the commercial production of fusion energy - the energy that one can become a source of electricity for our homes. Some day, perhaps, fusion reactors will allow us to Land safely use the star energy and soften thus our energy problems. But even thermonuclear reactor with magnetic retention will not be able to provide energy weapons like the death Star. This will require a completely new design.
X-ray nuclear-pumped lasers

There is another possibility to build a laser cannon death Star on the basis of current technologies using hydrogen bomb. Battery x-ray lasers, leash and focusing the power of nuclear weapons, could in theory provide enough energy to run the device that can blow up the whole planet.

Nuclear reactions release about 100 million times more energy per unit mass than chemical. A piece of enriched uranium, no bigger than a tennis ball would be enough to fry in a whirlwind of fire the whole city, despite the fact that energy becomes just 1% of the mass of uranium. As we have said, there are many ways of pumping energy into the working medium of the laser, and hence into the laser beam. The most powerful of these ways is far more powerful than all the others - is to use the energy of explosion of a nuclear bomb.

X-ray lasers have enormous significance, both military and scientific. A very small wavelength of x-ray radiation allows to use such lasers to probe atomic distances and decryption of the atomic structure of complex molecules that are extremely difficult to do with conventional methods. The ability to "see" atoms in motion and to distinguish their location inside a molecule makes a whole new way to look at a chemical reaction.

Hydrogen bomb emits enormous amounts of energy in the form of x-rays, therefore x-ray lasers can be inflated by the energy of a nuclear explosion. In science with x-ray lasers most closely associated Edward teller, father of the hydrogen bomb.

By the way, teller in the 1950s, testified before Congress that Robert Oppenheimer, who headed up this Manhattan project, cannot be trusted further work on the hydrogen bomb because of his political views. Indications teller has led to the fact that Oppenheimer was defamed and deprived of access to classified materials; many prominent physicists were never able to forgive the Teller.

(My own contacts with the teller began in high school. I then did a series of experiments on the nature of antimatter, won the main prize on science fair in San Francisco and a trip to the National science fair in Albuquerque, new Mexico. Together with the teller, who has always paid attention to talented young physicists, I took part in the broadcast of local TV. Later I got from teller engineering scholarship named Hertz, which helped me to pay for studies at Harvard. Several times a year I went to the Teller home in Berkeley, and there are quite familiar with his family.)

Fundamentally x-ray laser teller is a small nuclear bomb, surrounded copper rods. The explosion of a nuclear weapon spawns spherical explosive wave of intensive x-ray radiation. These high-energy rays pass through copper rods, which play the role of a working body of the laser and focus the energy of x-ray radiation in powerful beams. The received x-rays can then be sent to the enemy warheads. Of course, such a device can be used only once, as a nuclear explosion will lead to self-destructive x-ray laser.

The first test of an x-ray laser, called "test Cabra (Salga), was held in 1983 In the underground mine was exploded a hydrogen bomb, then a chaotic stream of x-rays from her focused and turned into a coherent x-ray laser beam. Originally tested were found to be successful; in fact this is the success in 1983, was inspired by President Reagan on the historic Declaration of intention to build a defensive shield from "Star wars". So was launched multi-billion construction program the network devices such as x-ray nuclear-pumped lasers to shoot down enemy ballistic missiles. Work on this program continues today. (Later it turned out that the sensor is designed to detect and measure radiation in the landmark trial, was destroyed; thus, his testimony that it was impossible to trust.)

Can there really knock warhead ballistic missiles with such trivial device? It is not excluded. But we should not forget that the enemy can think of a number of simple and inexpensive ways of neutralizing such weapons (so, it would be possible to deceive the radar, releasing millions of cheap decoys; or to give warhead rotation to dissipate thus x-ray radiation; or come up with a chemical coating, which would protect the warhead from the x-ray beam). Eventually, the enemy could just organize mass production of warheads that struck the shield of "Star wars" simply due to their number.

So the x-ray laser with nuclear pumping is not currently able to defend against missile attack. But is it possible to create on their basis the death Star, capable of destroying an entire planet or become an effective means of protection against an approaching asteroid?
Physics of Star death

Is it possible to create a weapon capable of destroying an entire planet, as in "Star wars"? In theory, the answer is simple: Yes. In several ways.

The energy released in the explosion of the hydrogen bomb, there are no physical limitations. That's what happens. (For a detailed description of the hydrogen bomb, even today, the US government refers to the highest category of secrecy, but in General it is quite well known.) The hydrogen bomb is made in several stages. By combining the desired number of stages in the proper sequence, you can get a nuclear bomb almost any pre-specified power.

The first stage is a standard bomb on the fission, or nuclear bomb; it is the energy of uranium-235 is used to generate a burst of x-rays, as happened in Hiroshima. For a split second before the explosion of the atomic bombs will blow it all to pieces, you receive an expanding sphere powerful x-ray pulse. This radiation ahead of the actual explosion (as moving at the speed of light); its time to re-focus and guide to the container with lithium deuteride targets - the active ingredient of a hydrogen bomb. (Exactly how this is done is still a state secret.) X-ray radiation falls on lithium deuteride targets, makes him instantly to shrink and heats up to millions of degrees, causing the second explosion, much more powerful than the first. A burst of x-ray radiation produced by this second explosion, you can then refocus on the second portion of lithium deuteride targets and call the third explosion. This is the principle, according to which should be placed near many containers with lithium deuteride targets and get the hydrogen bomb unimaginable power. So, the most powerful bomb in the history of mankind was a two-stage hydrogen bomb, which blew up in 1961 the Soviet Union. Then there was an explosion with a capacity of 50 million tons in a trotyl equivalent, although theoretically this bomb was able to give a capacity of more than 100 megatons of TNT (which is about 5,000 times more power of the bomb dropped on Hiroshima).

However, to ignite the whole planet needs very different capacity. To do this, the death Star would have to launch into space at thousands of these x-ray lasers, which then would shoot at the same time. (For comparison, in the height of the cold war, the United States and the Soviet Union have accumulated about 30,000 nuclear bombs.) The total energy of such a huge number of x-ray lasers have been enough to ignite the planet's surface. Therefore, the galactic Empire of the future, separated from us by hundreds of thousands of years, would, of course, to create such weapons.

For advanced civilization there is another way: to create a death Star, which would use the energy of the cosmic source of gamma-ray bursts. From this death Star would proceed flash radiation power second only to the Big Bang. The sources of gamma-ray bursts are natural phenomena, they exist in space; however, one could imagine that someday advanced civilization will be able to curb their enormous energy. It is not excluded, that if to take control of the rotation of stars long before its collapse and the birth gipernovae, it will be possible to send a "shot" of the source of gamma-ray bursts in any point of space.
The sources of gamma-ray bursts

Cosmic gamma-ray bursts were first discovered in the 1970s by running the U.S. military satellites "Led" (Vela)is intended for the detectionhelp "extra outbreaks" - evidence of illegal explosion of a nuclear bomb. But instead of flashes on the surface of the Earth satellites registered giant bursts of radiation from space. Initially unexpected discovery was summoned to the Pentagon real panic: " the Councils have a new nuclear weapon in deep space? It was later established that the bursts received uniformly from all directions of the celestial sphere; this meant that in fact they come in the milky Way galaxy from the outside[5]. But, assuming really extragalactic origin bursts, the power of their will truly astronomical because they are able to "cover" the entire visible universe.

After the collapse of the Soviet Union in 1990, the Pentagon suddenly has declassified a huge number of astronomical data[6]. Astronomers were astounded. They suddenly realized that they face a new mysterious phenomenon of those that make from time to time to rewrite the textbooks and reference books.

Duration gamma-ray bursts is small and varies from several seconds to several minutes, so for their detection and analysis of the necessary carefully organized system of sensors. First satellites register a burst of gamma-radiation and send to Earth exact coordinates of the source. The coordinates are passed on optical or radio telescopes, which, in turn, induced on the specified point on the celestial sphere.

Although currently on the gamma bursts know not all, one of the theories of their origin States that the sources of gamma-ray bursts - "gipernovae" the extraordinary power, leaving a massive black holes. In this case, it turns out that the sources of gamma-ray bursts - the monstrous black holes in the stage of formation.

But the black holes emit two jet, two streams of radiation from the South pole and from the North, as the rotating top. Radiation gamma-ray burst, which we register shall, obviously, one of these streams - one that was directed towards the Earth. If a flux of gamma-radiation from such a source would be directed exactly to the Earth, and the source would be in our galactic neighborhood (at a distance of several hundred light years from Earth), it would have enough power to completely destroy life on our planet.

First electromagnetic pulse generated by x-ray radiation from the source of gamma-ray bursts, would bring down all electronic equipment on the Ground. Powerful beam of x-ray and gamma radiation would cause the earth's atmosphere irreparable harm, destroying the protective ozone layer. Then the flux of gamma-radiation warms the Earth's surface, causing a terrible fire storm, which would cover the entire planet. Maybe the source of gamma-ray bursts and would not explode the planet, as shown in the movie "Star wars," but probably would destroy it all alive, leaving a charred wasteland.

It can be assumed that the civilization, way ahead of us in the development of hundreds of millions of years, will learn to direct such black holes at the desired target. This can be achieved if you learn to control the movement of the planets and neutron stars and guide them in the dying star under precisely calculated the corner just before the collapse. A relatively small effort will be enough to reject the axis of rotation of the star, and point her in the right direction. Then the dying star becomes the largest beam gun, imaginable.

To summarize. Using powerful lasers to create a portable or handheld radiation weapons and lightsabers should be allocated to the class I inability is likely that this will be possible in the near future or, say, in the next hundred years. But very, very challenging target of a rotating star before the explosion and turn it into a black hole, i.e. its transformation into the death Star, should be considered as a failure class II - something that is not obviously contradicts the laws of physics (as sources of gamma-ray bursts exist in reality), but can be implemented only far in the future, thousands or even millions of years.