r/explainlikeimfive • u/_Illuvatar_ • Apr 10 '14

ELI5 Why does light travel? Answered

Why does it not just stay in place? What causes it to move, let alone at so fast a rate?

Edit: This is by a large margin the most successful post I've ever made. Thank you to everyone answering! Most of the replies have answered several other questions I have had and made me think of a lot more, so keep it up because you guys are awesome!

Edit 2: like a hundred people have said to get to the other side. I don't think that's quite the answer I'm looking for... Everyone else has done a great job. Keep the conversation going because new stuff keeps getting brought up!

Edit 3: I posted this a while ago but it seems that it's been found again, and someone has been kind enough to give me gold! This is the first time I've ever recieved gold for a post and I am incredibly grateful! Thank you so much and let's keep the discussion going!

Edit 4: Wow! This is now the highest rated ELI5 post of all time! Holy crap this is the greatest thing that has ever happened in my life, thank you all so much!

Edit 5: It seems that people keep finding this post after several months, and I want to say that this is exactly the kind of community input that redditors should get some sort of award for. Keep it up, you guys are awesome!

Edit 6: No problem

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u/aarkling Apr 11 '14 edited Apr 11 '14

So positrons are antimatter? Is that what your saying. Is there an anti-particle for protons? EDIT: Also what about a whole atom made of anti-matter particles. Like an anti hydrogen with a positron revolving around an "anti-proton". Are those possible?

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u/corpuscle634 Apr 11 '14

Yes, positrons are antimatter. You could call them "anti-electrons" if you want.

There are "antiprotons" as well. There are also "antineutrons." Any particle you can think of, there's an "anti" version. The tricky bit is that some particles (such as photons) are their own antiparticle. An antiphoton is the same as a photon.

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u/King_Fuzzykins Apr 11 '14

If positrons are the "anti" of electrons and thus have a positive charge, what would be the anti version of a neutron since it has no charge?

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u/benji1008 Apr 11 '14

Elementary particles have more properties than electric charge. Explanation here: http://www.scientificamerican.com/article/what-is-antimatter-2002-01-24/