Speed of Light – I’ve never seen it explained this way #physics #science

The speed of light in a vacuum is a constant – a serious constant that never varies no matter your frame of reference. I can write the words, but the concept is hard to grapple with. My intuition has been crafted here on the surface of a pretty little planet where there is always something that can go faster than something else. But forget intuition.

The most common explanation for this cosmic speed limit is that as an object goes faster and faster, its mass increases. And this explanation makes some sense. After all, it’s harder to push a mountain than a pebble. If the mass of objects become infinite as they get closer to the speed of light, it makes sense that you cannot break that speed barrier — it would take infinite energy to accomplish. BigThink.com

I can read those words too… but… mass gets bigger?

Einstein, the year he completed his dissertation and published four groundbreaking papers. The guy was quite something.

How about this: You can move through space, like intuition tells you. And you move through time (though you can’t control that rate, not as a clock measures it.) Einstein said, any object is traveling through both space and time: through spacetime. Part of its journey is through space and part is through time. That’s not so hard.

When the theory was pushed harder, what was revealed was that every object travels through spacetime at a single speed — the speed of light. From one of Einstein’s professors, mathematician Hermann Minkowski

The maths are beyond my abilities, but… okay. “If you move at fixed speed, you can move in any direction you want, but in no direction can you move faster than that fixed speed. And it’s identical in spacetime.”

Objects move in spacetime at the speed of light. A stationary object isn’t moving through space at all, so the object is moving through time at the speed of light. Furthermore, an object moving through space at the speed of light has no speed left over to move through time.

Thus, the absolute maximum speed an object could move through space or time individually is also the speed of light. Note that this idea also explains the weird features of relativity, like time slowing down for an object as its speed gets faster and faster. An object traveling more through space is traveling less through time.

So, that’s it. The real reason you cannot travel through space faster than light is because you are always traveling through spacetime at the speed of light. The best you can do is transport all your effort into moving through space; but, once you have pushed all your motion in the space direction, there just isn’t any more speed left. BigThink.com

I’ve quoted a lot from the article because I’m still absorbing the “wow.” Now, I need time to let it settle into my brain (at the speed of light.) Of course, I still don’t know why there is a limit to the speed of light, but (hand-wave) that’s just somewhere in the math. Thanks to Don Lincoln for his article.