Are there ways to travel at the speed of light?

A few days ago, the centenary of the verification of the theory of general relativity of Albert Einstein, the ideas that are the basis of how we understand the world today. An eclipse proved how light bends due to gravity, agreeing with the great physicist and taking it from himself Isaac Newton.

But Einstein’s postulates went further: already in his theory of special relativity -to which nobody paid much attention- he affirmed that light was much more and that its particles they were traveling through a vacuum at a constant rate of 299,792,458 meters per second (1,080,000,000 kilometers per hour), a speed that is immensely difficult to reach and impossible to overcome in that environment.

A revolutionary idea that still today provides guidance for us to understand, among other things, the mechanics of space, and keep spacecraft and astronauts safe from radiation.

Speed ​​of light

Throughout the universe, from black holes to our near-Earth environment, particles are, in fact, accelerating to incredible speeds, even reaching the 99.9% of the speed of light. One of the jobs of space agencies is to better understand how these particles are accelerated.

The study of these super fast particles, also called relativistic, can help protect future missions to the moona Marsfor learn more about our cosmic neighborhood or, who knows if, as some suggest, create new propulsion systems for our ships.

But how do you get these almost sci-fi accelerations? Scientists point to three specific forms, as collected by the specialized portal Phys.org.

Light: electromagnetic fields

Most of the processes that accelerate particles to relativistic speeds work with electromagnetic fields, the same force that keeps magnets glued to your fridge. the two components, electric and magnetic fieldlike two sides of the same coin, work together to move particles at relativistic speeds throughout the universe.

electromagnetic fields accelerate charged particles because it pushes them, similar to how gravity attracts objects with mass. Under the right conditions, electromagnetic fields can accelerate particles to near the speed of light.

On Earth, electric fields are often harnessed in laboratories – albeit on a smaller scale – for laboratory experiments.

But they are not as small as they may seem: particle accelerators, such as the Large Hadron Collider and the fermilab -which occupy tens of kilometers-, use pulsed electromagnetic fields to accelerate charged particles up to 99.99999896% of the speed of light.

At these speeds, particles can break apart to produce collisions with immense amounts of energy. This allows scientists to search for elementary particles and understand what the universe was like in the first fractions of a second after the Big Bang.

magnetic explosions

The magnetic fields are everywhere in space: surrounding the Land and encompassing the Solar System. They are responsible for guiding charged particles moving through space, which rotate around them.

When these magnetic fields collide with each other, they can become entangled. And the moment the tension between the crossed lines becomes too great, the lines explosively snap and realign.

This is a process known as magnetic reconnection: The rapid change in the magnetic field of a region creates electric fields, which causes all charged particles to travel at high speeds.

Scientists suspect that magnetic reconnection it is a way in which particles, for example, the solar wind -which is the constant flow of charged particles from the sun-, accelerate to relativistic speeds.

But those fast-moving particles also create a variety of secondary effects near planets. Thus, on our planet we can observe them in the form of northern lights: When a magnetic reconnection occurs on the side of the Earth that is away from the Sun, the particles can be launched into our planet’s upper atmosphere, where they produce the auroras.

Magnetic reconnection is also thought to be responsible for other effects around other planets such as Jupiter and Saturnalbeit in slightly different ways.

The results of the analyzed data can help scientists understand the acceleration of particles to relativistic speeds around the Earth and throughout the universe.

Wave-particle interactions

Apart from the two methods already mentioned, particles can be accelerated by interactions with electromagnetic waves, called wave-particle interactions. When electromagnetic waves collide, their fields can be compressed. Charged particles bouncing between the waves gain energy, like a ball between two surfaces that are brought together.

These types of interactions occur constantly in near-Earth space and are responsible for accelerating particles to speeds that can damage the electronic components of spacecraft and satellites in the space.

Wave-particle interactions are also thought to be responsible for accelerating some cosmic rays that originate outside our Solar System. After a supernova explosion, a hot, dense layer of compressed gas—called a blast wave—is ejected from the stellar core.

Filled with magnetic fields and charged particles, these bubbles’ wave-particle interactions can launch high-energy cosmic rays at 99.6% the speed of light. Furthermore, it is believed that wave-particle interactions may also be partially responsible for accelerate solar wind and cosmic rays of the sun.

Font: ABC

Reference article: https://www.abc.es/ciencia/abci-tres-formas-viajar-casi-velocidad-201906031503_noticia.html