What Is The Fastest Thing In The Universe?

Light thinks that it travels faster than anything else, but is wrong. No matter how fast light travels, it finds the darkness has always got there first and is waiting for it - Terry Pratchett 

Physics and the laws that govern it are irrefutable and whether we’re aware of the way they constantly act upon us and our surroundings or not, they are the singular set of forces that govern the world and the way in which we perceive it.

And as most physicists will happily, and readily tell you if asked about momentum or velocity, that speed, just like Einstein’s most famous theory, is relative.   

As correct as that universal truism is though, there is, and always has been only one universal speed champion and that is light.

Traveling at one hundred and eighty-six thousand two hundred miles a second, light is faster than any other thing in the universe and crosses vast galactic distances at a pace that is almost impossible to comprehend in terms of the way that we think of speed and distance in an everyday context. 

The best way to explain the velocity and rate at which light travels is by looking at how long it takes light from the Sun to reach Earth.

It takes eight minutes for light to travel from the Sun to us, and in that time it covers a distance of ninety-three point four million miles, which is the equivalent of circumnavigating the globe three thousand seven hundred times. In eight minutes. 

Light travels so fast, that every time you look at the sun, you’re not seeing it in real-time. The sun that you’re looking at is eight minutes and twenty seconds old, so when you look at it, you’re gazing into history and seeing the past and not the present.

Which when you think about it, is like traveling in time. That means that light is so fast, that it can almost out race time itself. 

What Happens If You Travel Faster Than Light? 

We should probably point out that it is, according to the General Theory of Relativity, impossible to travel at the speed of, or faster than light. 

Regardless of what James Tiberius Kirk or Jean Luc-Picard would like you to believe, it is a universal constant that you cannot beat light in a race. 

If it were possible to reach that kind of velocity and travel at the same speed that light does, and you managed to do so, time would no longer be constant.

In theory, and it is just speculative theory at best if you were to travel at the speed of light, time while passing normally for everyone else, would slow down for you. 

This means that if you were to journey to Proxima Centauri, the nearest extrasolar star to Earth at the speed of light, the journey would take four and half years for you, but for your nearest and dearest who stayed behind on Earth, the journey might have taken fifty years or more. 

Does Light Have Any Challengers? 

While light doesn’t ever have to worry about losing its place at the top of the universal speed tier, there are a couple of challengers in the universe that come incredibly close to keeping up with it. 

Super hot gas that is expelled from blazars, or active galactic nuclei (AGNs), can reach speeds of point nine nine of the speed of light.

While they’re not quite as fast as light is, these blobs of gas are one of the fastest ways in which matter can travel across the universe. 

That’s right, you didn’t misread the last paragraph. We did say that the blobs that AGNs blasted out were ONE of the fastest ways for matter to travel.

The other challenger to light’s unbroken velocity record are the ultra-high-energy cosmic rays that continually assail our planet and every other celestial body in the universe. 

Just like the aforementioned blobs of superheated gas, they can travel at point nine nine of the speed of light, and even though the matter that they contain isn’t larger than a photon, the rays are still pushing a form of matter at a speed that comes close to the fastest thing in the universe. 

What Is The Slowest Thing In The Universe? 

For every action, there is an equal and opposite reaction, and if there is a fastest thing in the universe, then logically there must be a slowest thing in the universe as well.

And there is, or rather according to different points of view, there are a number of slow-moving objects that are continually vying for the crown that adorns the head of the slowest thing in the universe. 

Some physicists will tell you that the slowest moving thing in the universe is Xenon-124, a radioactive noble gas that has a half-life that is one trillion times slower than the age of the universe, which definitely makes it a contender for the tile. 

Others however argue that the slowest moving thing in the universe is the cosmic microwave background or the red-shifted form of light that has been around since the Big Bang and hasn’t really gone anywhere or moved in the last thirteen point eight billion years. 

The truth though is far simpler and much easier to comprehend. The slowest moving thing in the universe at any given point in time is you.  That’s because you are continually observing everything moving around you, and past you.

You’re the observer in your own microcosm of universal space and relative to everything that is happening and occurring around you at every single moment, you are the slowest moving thing in the universe.  

All of the matter in the universe is constantly swirling around you, and it doesn’t matter how fast you are traveling, whether you’re walking or running, behind the wheel or car or traversing the glove as a passenger in a high-speed aircraft, relative to where you are and what you are doing, you will always be the slowest moving object in the universe.