Forbes (USA): can we achieve interstellar travel using only known to us in physics?

Since then, as people looked into the night sky, we dream of visiting other worlds and to see the Universe. And while our rockets on chemical fuel has already reached many planets, moons and other Solar system bodies, spacecraft, retired at the greatest distance from Earth, Voyager 1, crossed only 22.3 billion kilometers. It’s just 0,056% of the distance to the nearest known us star system. If you use modern technology the way to another star system will take about 100 thousand years.

However, there is no need to act the way we always did. The effectiveness of sending vehicles with a large payload mass, even with people on Board, to unprecedented distances in the Universe, can significantly improve if you use the right technology. More specifically, there are four promising technologies that can take us to the stars over a much shorter period. Here they are.

1). Nuclear technology. To date in human history, all objects launched into space have one thing in common: the engine on chemical fuel. Yes, rocket fuel is a special blend of chemicals designed to provide maximum traction. It is important the phrase “chemical substances”. Reaction that gives energy to the engine, based on the redistribution of the bonds between the atoms.

It fundamentally restricts our actions! The vast majority of the mass of an atom have in its nucleus is 99.95%. When it starts a chemical reaction revolving around atoms, the electrons are redistributed and are usually isolated in the form of energy of about 0.0001% of the total mass of the atoms involved in the reaction, according to the famous Einstein equation: E=mc2. This means that for every kilogram of the mass of fuel loaded into the rocket during the reaction, you get energy equivalent to approximately 1 milligram.

However, if you use rockets powered by nuclear fuel, the situation will be dramatically different. Instead of having to rely on changes in the configuration of electrons and the relationships of atoms to each other, you can release relatively huge amounts of energy, affecting the relationship of the nuclei of atoms together. When you split the uranium atom by bombarding it with neutrons, it emits much more energy than any chemical reaction. 1 kilogram of uranium-235 can release amounts of energy equivalent to 911 milligrams of the mass, which is almost a thousand times more efficient than chemical fuel.

We could make engines much more efficient if mastered nuclear fusion. For example, a system of inertial controlled thermonuclear fusion, by which it would be possible to synthesize hydrogen into helium, a chain reaction occurs in the Sun. Synthesis of 1 kilogram of hydrogen fuel to helium will make 7.5 pounds of mass into pure energy, which is almost 10 thousand times more efficient than chemical fuel.

The idea is to get the same acceleration for the missiles in a much greater period of time in hundreds or even thousands of times longer than it is now, would develop hundreds or thousands of times greater speed than conventional rockets now. Such a method would reduce the time interstellar flight to hundreds or even tens of years. This is a promising technology, which we will be able to take advantage of already by the year 2100, depending on the pace and directions of development of science.

2). The beam space lasers. This idea is the basis of the project “Breakthrough Starshot”, became famous a few years ago. Over the coming years, the concept has not lost its attractiveness. Whereas conventional rocket carries fuel with you and spending it on acceleration, the key idea of this technology — a powerful beam of lasers that will give the spacecraft the necessary boost. In other words, the source of the acceleration is separated from the vehicle.

This concept is at the same time and exciting, and in many ways revolutionary. Laser technology is successfully developed and become not only more powerful, but also highly collimated. So, if we create a similar to the sail material, which will reflect a fairly high percentage of the laser light, you can use laser shot to space ship has developed a tremendous speed. “Starship” with a mass of ~1 gram is projected to reach speeds of ~20% the speed of light, which will allow him to reach the next nearest star Proxima Centauri in just 22 years.

Of course, for this we will have to create a huge beam lasers (about 100 km2), and it must be done in space, although there is the bigger issue here is cost, not technology or science. However, there are some problems that need to be overcome in order to be able to undertake such a project. Among them:

  • does not support the sail will rotate, it is necessary for a (yet undeveloped) stabilizing mechanism;
  • the inability to slow down when you reach the point of destination, as there was no fuel on Board;
  • even if you manage to scale the device for transporting people, people will not be able to survive with a huge acceleration – significant difference in speeds for a short period of time.

Maybe someday technology will be able to take us to the stars, but successful method, as a person to reach a speed equal to ~20% the speed of light does not exist yet.

3). Fuel on the basis of antimatter. If we still want to carry fuel with you, you can make it the most effective possible: it will be based on the annihilation of particles and antiparticles. Unlike chemical or nuclear fuel, where only part of the available on-Board mass is converted into energy, annihilation of particles and antiparticles uses 100% of the mass of particles and antiparticles. The ability to convert all the fuel in the energy for the pulse — the highest level of fuel efficiency.

In applying this method in practice in three main areas there are difficulties. Specifically:

  • the creation of a stable neutral antimatter;
  • the ability to isolate it from ordinary matter and just to control it;
  • producing antimatter in large enough quantities necessary for interstellar flight.

Fortunately, over the first two problems are already working.

In the European organization for nuclear research (CERN), where is the Large hadron Collider, is a huge complex, known as the “antimatter factory”. There are six independent teams of scientists explore the properties of antimatter. They take antiprotons and slows them, causing the center to contact them. So which anti-atoms are created or neutral antimatter.

They isolate these which anti-atoms in a container with changing electric and magnetic fields that keep them in one place at a distance from the walls of the container made out of matter. To date, the middle of 2020, they successfully managed to isolate and maintain in stability a few antiatoms for hours at a time. In the next few years scientists will be able to control the movement of antimatter within the gravitational field.

This technology will not be available to us in the near future, but it may be that our fastest way to interstellar travel — the rocket for antimatter.

4). The spaceship on the dark matter. This option, of course, relies on the assumption that any particle responsible for dark matter, behaves like a boson is its own antiparticle. In theory dark matter is its own antiparticle, has a small, but not zero, chance to annihilate with any of the other colliding with her a particle of dark matter. Released as a result of collision energy, we can potentially use.

There is possible evidence of this. As a result of observations found that the milky way and other galaxies have an unexplained excess of gamma radiation coming from their centers, where the concentration of dark energy should be highest. There is always the possibility that there is a simple explanation for astrophysics, e.g., pulsars. However, it is possible that all dark matter will annihilate with itself in the center of the galaxy and thus gives us an incredible idea — the spaceship on the dark matter.

The advantage of this method is that dark matter exists everywhere in the galaxy. It means we don’t have to carry fuel along for the journey. Instead, the “reactor” of dark energy could simply do the following:

  • take any dark matter, which is next;
  • to speed up its annihilation or allow it to annihilate in the natural way;
  • to redirect the received energy to get momentum in any desired direction.

People could control the size and power of the reactor to achieve the desired results.

If you do not need to have the fuel on Board will resolve many of the problems of space travel driven propulsion units. Instead, we will be able to achieve the cherished dream of a journey — unlimited constant acceleration. This will give us the most incredible ability — the ability to reach any place in the Universe in a single human life.

If we limit ourselves to existing missile technology, we will need at least tens of thousands of years to travel from Earth to the nearest star system. However, a significant advance in engine technology is close, they will reduce the journey time to a human life. If we can cope with the use of nuclear fuel, beam space laser beams, antimatter or even dark matter, we will fulfill his own dream and become a space civilization without the use of violate physics technologies such as warp drive.

There are many potential ways to turn scientific ideas into workable, real technologies of next-generation engines. It is possible that the end of the century a space ship that is not yet invented, will take the place of New horizons, the Pioneer and Voyager the most distant from Earth man-made objects. The science is ready. We have to look beyond our current technology and to fulfill this dream.