Prem Mehta

Python Programmer Interested In Quantum Mechanics And Math

1 minute read

I named the first post in this section “The Invisible Force” - but gravity isn’t actually an invisible force. It isn’t even a force itself. In the next two blog posts, I will explain Einstein’s relativity and why gravity isn’t a force, but rather the curvature of space-time.

Symmetry

Before we get into special relativity, we must go over symmetry. Symmetry is the principle that the laws of nature remain the same after a transformation. A transformation could refer to moving in space or time. Let’s say, for example, you do the same experiment many times in different places, and the physical laws don’t change. The physical laws would be symmetrical. Einstein used symmetry to develop the special relativity.

Space-Time

Before Einstein published his theory of relativity, people thought space and time were two separate things. In 1905, Albert Einstein unified space and time together into a single four-dimensional spacetime. This was a mind blowing understanding of space and time, which changed everything on how we see things today. This unification was proven to be correct, which you will find more about in the next post.

The Two Pillars

Einstein’s theory of special relativity comes in two main parts. For any object moving at a constant speed, the laws of physics are all the same. And the speed of light in a vacuum, also known as the universal speed limit is always the same, about 300,000 km/s. Since it’s not possible to move faster than the speed of light, there must be a change as we move faster.

  • Time Dilation: Time ticks slower as we move faster.

  • Length Contraction: The length of an object shortens as it approaches high speeds.

  • Mass-Energy Equaivalence: Mass and energy are equivalent.

Conclusion

As you can see, Einstein’s theory of special relativity changed our understanding of space and time. Einstein used symmetry when developing the principle of relativity and the constancy of the speed of light. The next post will also be about Einstein’s theory of relativity. Make sure to check out my other posts!

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