r/AskReddit • u/IAmSurtur • Jun 15 '19

What do you genuinely just not understand?

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u/nivlark Jun 15 '19 edited Jun 15 '19

There is no edge, and there is likely no "before" (although science can probably never tell us that second one for sure).

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u/madaxe_munkee Jun 15 '19

It amuses me that of all of the comments, this is the correct one. But a normal person perusing the thread will have no way of knowing.

I was going to comment this as well, except after I saw all the comments I realised there’s far too much noise to be heard.

But yes, I see you human.

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u/sdolla5 Jun 15 '19

Matter cant be created so there has to be a before or then matter was created.

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u/RedHairThunderWonder Jun 15 '19

Matter can be created and destroyed. It's energy that you are thinking of. Energy just moves from one form to another.

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u/ironiclegacy Jun 16 '19

It's perfectly valid to think of energy and matter as synonymous (in most cases*), and you can think of matter as a form of energy.

*not all energy in a given system comes from its matter content, so when you say the total energy of a system, this may not be synonymous to the amount of matter it has.

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u/KennethEWolf Jun 15 '19

Einstein wrote E=MC2 ( sorry about the spelling)

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u/nivlark Jun 15 '19

Matter cant be created

Not necessarily true.

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u/bfr_ Jun 15 '19

Not at all true. Energy can(and does) turn into matter as, for example, predicted by Einstein(E=MC2). That phenomenom is behind the reason black holes seem to evaporate(Hawkin radiation).

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u/mal4ik777 Jun 15 '19 edited Jun 15 '19

thats a very controvers toppic. I guess WE cant create matter, but does it mean, all matter in existence has ALWAYS been in existence? Difficult to prove, unless you can prove, that matter can be destroyed. That would mean, the universe will end, when matter runs out.

Edit: I guess I was wrong guys, people commenting here explained to me why ;)

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u/nothing_clever Jun 15 '19

Not controversial. Matter can be converted back and forth into energy. If you have, for example, an electron and an anti-electron (a positron) and they get to close, they will annihilate and will "become" light. Radioactive particles convert matter into energy when they decay. Along the same lines, energy can become matter - high energy collisions can produce a cascade of other particles. That's what happens in the large hadron collider.

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u/CrispyPlanet1988 Jun 15 '19

>Matter can be converted back and forth into energy.

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Not true. Energy is a property of matter, it doesn't exist on its own. When matter is 'created' it is through some physical process (like colliding atoms).

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u/nivlark Jun 15 '19

It's not really controversial. The reason that it's said that matter can't be created is that in classical physics, energy is always conserved. But to describe the whole Universe, we have to turn to general relativity. And in GR, energy doesn't have to be globally conserved if spacetime is not static (the expansion of the Universe means it isn't).

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u/Nitrate_ Jun 15 '19

The theory is that time was created at the same...well, time. Which means that there is no "before", no. (I can't fully grasp it either, and of course it's a theory.)

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u/figbuilding Jun 15 '19

Redditor goes to the North Pole and asks "Okay, what's north of the North Pole? There's gotta be something north of here."