I usually see myself as being pretty solid on my general science knowledge, but this one continues to stump me.
Light is photons, little particles that move through space… but then it’s also a wave, like the visible light portion of the electromagnetic spectrum? How can it be both? How would photons red shift over great distances? Do we just not know what light is, really?
In: 9
This is a real, real basic ELI5, but…
Physics “changes” at scale. Behaviours are different.
Think of a little plastic ball. Imagine bouncing it around. Now, imagine a net holding 10 of those balls. Imagine bouncing that around. Change the shape of the net. Make it longer. Wider. Imagine throwing it through a window. A small gap. Down a hall way.
Make it a lot bigger. Make it the size of a house. How would it react to manipulation?
What if the balls were actually bowling balls, or even baseballs? The behaviour at every stage would be radically different, and we have a different set of problems to think about when throwing them around.
Well, it’s kind of like that. Light behaves as a wave, but as we break it down in to more discreet chunks, we start to *quantise* how we think of light, turning from electromagnetic waves to photons, and turn from classical physics to *quantum* physics. Just like you will get different behaviours by changing the “shape” of your net, or the amount of balls inside of it, or what you throw it through, we can manipulate and experiment with these aspects of light.
Now, there is a lot to ask *why* and *how* these things occur, but when we’re working at this scale, the behaviour shifts again and we begin to get *spooky* things occuring. These are the questions people are working towards solving now. 🙂
If anyone wants to correct anything, please do so!
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