The speed of light surpasses everything
Albert Einstein also believed that the speed of light must be a constant. He started with another scientist's theory of light, namely the Scottish physicist James Clerk Maxwell. Maxwell believed that a beam of light moves forward by a small bit of electricity which, as it moves forward, forms a magnetic field that follows and forms new electricity. A kind of jumping jack.
But Maxwell never fully grasped how light could move faster or slower.
Albert Einstein introduced a completely new thought. Namely, that light always moves at the same speed. Completely independent of whether it is sent out from a moving point or not.
Einstein also suggested that because electricity is always pushed forward by the resulting magnetism, it will be faster than anyone following behind. Light waves jump at the ultimate physical speed in the universe. What is Albert Einstein’s IQ?
Mass is solidified energy
And what does the speed of light have to do with mass and energy? Imagine a space shuttle approaching the speed of light. The pilot continues to supply energy to the engines, but the energy cannot be used to exceed the speed of light. And the energy can't just disappear either. Instead, it is compressed into pulp. The space shuttle is simply getting bigger. E (energy) becomes m (mass).
The sun is a reversed example. Every second tons of hydrogen (mass) is lost and transformed into energy.
Every substance on earth is thus "solidified" energy. And if the energy can be released, even a piece of paper has the potential to take over the energy supply in all of Sweden.
But it is not easy to release energy. The fuels we use to obtain energy (for example petrol) only release a fraction of the bound energy.
Albert Einstein's theory of relativity shows that light has a constant speed and thus it also affects our understanding of time. Namely, time is relative and the fact that we perceive time differently is called time dilation.
Let's take an example of time dilation:
The fact that light has a constant speed also affects our understanding of time. When two spacecraft send out a flash of light toward Earth, the light travels at the same speed from both spacecraft.
But if one spacecraft is stationary and the other is moving in the same direction as the light, there will be a difference in how long it takes to reach Earth. It depends on which spacecraft you are in. On a stationary spacecraft, time will pass faster than on board a moving spacecraft.
It can be difficult to accept because we are not used to moving near the speed of light. The speeds at which we move on Earth are so infinitely low that we do not experience variations in time.
But time is relative unlike the speed of light which is constant.
Here you can see a video that explains the relative time phenomenon:
The twin paradox
The relative time is often illustrated with pairs of twins where one travels to a star several light years away, while the other stays on Earth.
The transport is close to the speed of light and as we saw earlier, time will pass more slowly for the twin that is in motion than for the twin that is "standing still" on Earth.
Because time passes more slowly for the traveling twin relative to the twin remaining on Earth, the astronaut twin will age more slowly. In fact, they will be several years younger than their twin when they return home.
American astrophysicist Neil deGrasse Tyson explains it in this video about relativity and the twin paradox: