"Matter can neither be created or destroyed." Who said this, and what, exactly, does it mean?

It’s the second law of thermodynamics. A principle of physics rather than a specific quote.

I know it’s the second law of dynamics, but what does it mean?

My science teacher told us that once, and then he became a principal, so he was like a principal of physics, and then he became the superintendent which is an entirely different things…

It means that when you burn something if you could gather the gas released the ashes and everything it would add up to the same as the whole that was burned

basically and stupidly put, sorry im not a science guy

said better below

Pretty self-evident; that the energy that is in matter is converted into another form of energy if it is changed. Think of water being frozen into ice or evaporating into air; it doesn’t go away, it just changes.

So the matter that makes up our bodies, our minds, our brains, has been around since the universe began?

Seems to be implied, I don’t know, I don’t tend to do well with questions like this, if someone disagrees with what I say or asks why, I end up shouting “because I say so!” As my response.

So why would you even open up and comment in a question like this, or the other one about where water comes from? I can see you’re new, but, FYI, you aren’t required to answer all the questions. It’s OK to ignore them if you want.

So, is “matter” referring to atoms, or to the protons, neutrons and electrons that make up the atoms?

@Dutchess_III have you ever been really bored? Like really really bored? Yeah that’s why, I haven’t had a client in weeks, it’s getting down right depressing. So basically answering these questions is fun, even if it makes me look like an idiot. That’s all.

Last time I was that bored I posted a Q about food stamps and pyjamas. I was not bored for the next 2 months! It’s hard to be bored when you are getting beat to hell! :)

So, the original form is the conservation of matter, it’s now known that what we actually have is the conservation of energy, though they are technically the same thing, which we’ve known since Einstein figured out E=mc^2. We can actually annihilate matter (matter-antimatter reactions do exactly that), but it doesn’t annihilate it as much as convert it into the equivalent amount of pure energy. And through a similar way we can technically create matter out of energy, though I don’t think we’ve accomplished that yet.

So, yes, the result of that means that since the big bang the total amount of energy in the universe has been constant, though the relative amount of pure energy to matter, the forms of that energy and matter (for instance, the universe was almost entirely helium and hydrogen until the first stars formed) as well as the density of energy (way, way higher at the beginning, and going to be so low that nothing can occur any more at the ‘end’ unless there’s a new big bang, which is possible), has changed over time.

Thanks @BhacSsylan.

Recognize that the very molecules that make up your body, the atoms that construct the molecules, are traceable to the crucibles that were once the centers of high mass stars that exploded their chemically rich guts into the galaxy, enriching pristine gas clouds with the chemistry of life. So that we are all connected to each other biologically, to the earth chemically and to the rest of the universe atomically. That’s kinda cool! That makes me smile and I actually feel quite large at the end of that. It’s not that we are better than the universe, we are part of the universe. We are in the universe and the universe is in us. – Neil deGrasse Tyson

Nice, @Blondesjon! Thank you.

The only exception is when matter falls into a black hole. It sort of leaves our universe then though its gravitational effects remain.

I don’t think so @flutherother. It just gets ripped down into the very smallest bit of energy that it possibly can. If it didn’t, if it was completely destroyed, the largest black holes would have the same gravitational density as the smallest ones, but they don’t, so there’s something in there still working.

@flutherother Yeah, that’s not true, at least from everything we currently know about them. Black holes do eventually (eventually as in billions upon billions of years for most) ‘evaporate’ via Hawking Radiation, however that again is transforming matter into energy, the matter is converted into the ejected hawking radiation, it doesn’t go anywhere.

How do they “evaporate” @BhacSsylan?

PhiNotPi is stuck in the fluther black hole I think!

I should mention this is a hypothesis, they’re searching for proof now. However, according to quantum mechanics, a black hole must emit radiation over time. I won’t defend the equations much since I’m a chemist, not a astrophysicist, but I think Hawking is rather trustworthy in that regard. So, if they emit radiation, in order to satisfy the conservation of energy they must lose mass. A black hole that ‘eats’ constantly would grow, but if it doesn’t energy is still emitted and so over time the black hole will shrink. This is actually an accelerating process as the black hole heats as it shrinks, increasing the rate of emission, and so eventually it’ll emit all it’s stored matter as energy and cease to exist as a black hole.

This is part of the reason the stories about the Hadron Collider destroying the world via black holes was wrong, while under some theories the LHC can create black holes, they’d evaporate almost instantaneously. However, this hasn’t been seen to occur yet, anyway.

This phrase can be interpreted on a few different “levels.”

In the context of chemistry, it refers to the fact that chemical reactions only rearrange atoms. It means that the number and types of atoms is equal on both sides of a reaction. An atom can never be created, nor destroyed, in a chemical reaction. The atoms are merely rearranged.

Let’s say that you have some methane (CH4). Then, you set the methane on fire. The reaction is as follows:

CH4 + 2O2 = CO2 + 2H2O
(methane + 2 oxygen gas = carbon dioxide + 2 water).

If you add of the mass of the methane/oxygen molecules, and compare it to the combined mass of the carbon dioxide/water molecules, you will find that the masses on both sides are equal.

The next level would be in the case of nuclear physics. The equation E=mc^2 comes into play. As nuclear bombs have demonstrated, it is indeed possible to “destroy” a small percentage of matter during a nuclear reaction. When matter is destroyed, it releases energy.

The reason that nuclear weapons release energy is because of something called “mass defect.” Basically, protons and neutrons can be arranged in different ways, giving way to the different elements with different potential energies. Potential energy manifests itself as mass, so an atom will weigh ever-so-slightly less than the sum of its parts.

A common nuclear reaction is:

U235 + n = Kr92 + 141Ba + 3n
(the n’s are neutrons)

In this example, if you add the weight of the left hand side, you will find that it will weight more than the right hand side. Where does that mass go? If you count the particles (protons/neutrons) on both sides, you will find that the sum has not changed.

When the uranium splits, it lowers its potential energy, reducing the mass of the result. This lost mass is converted into energy. Since it is multiplied by a factor of c^2 (the speed of light squared), a small amount of mass creates a lot of energy.

On an even deeper level, the relationship between mass and energy can become very blurry. In subatomic physics, mass is easily turned into energy, and vice-versa. In fact, when it comes to subatomic particles, mass and energy are the same thing.

Black holes evaporate via Hawking radiation. It’s rather complicated, I don’t understand all of the math behind it.

Hawking radiation doesn’t involve matter escaping the gravity of the black hole, as it rather involves negative matter being created outside of the black hole and entering it.

I have proof that the Hadron Collider screwed things up. Their first test happened while I was on Wis.dm, and Wis.dm no longer exists. That is proof.

OK. I see. Sort of @PhiNotPi…..Could it be compared to, like, there is a fire in the hole, and water is being created outside the hole and getting sucked in and putting the fire out? I know it’s simplistic.

@PhiNotPi Wow. Thank you! It’s like, DAB rearranged is BAD. Still the same letters, but a completely different meaning. (The Jehova’s Witnesses once tried to tell me that Santa Clause is really evil, because it you rearrange the letters in Santa you end up with Satan. I said, “OK, so what does it mean that when you rearrange the letters in GOD you come up with DOG?”)

In one of my university engineering classes we had to estimate the number of molecules of nitrogen we inhale that came from Julius Caesars last breath. Of course there were plenty of assumptions but the answer was quite surprising. If I recall it was something like 7. Every breath you take contains on average 7 molecules that Caesar exhaled when he died. The nitrogen likely never broke down. How awesome is that?
In fact I probably inhaled one of yours just now. (Did you have fish fry last week?)

He sure was one windy dude, wasn’t he?

I’m glad we haven’t tried to calculate where the hydrogen and sulfur went from his last fart, and how much of that we’re breathing. On the other hand, there are folks who, realizing that, might decide not to breathe again, and that might be a very fine thing.

@PhiNotPi is on the right track. Anyone who says matter cannot be created or destroyed is ignoring the Big Bang, which created all matter and energy, and has worded their statement poorly, because mater can be converted into energy, and then it isn’t matter anymore. What’s more, matter and energy are constantly being created and destroyed in what we perceive as the void of space, because nothing is not actually our concept of nothing, at least not at the quantum level. It is a boiling, seething sea of quantum possibilities in which particle/antiparticle pairs poof into and out of existence constantly.

Hawking radiation around the event horizons of black holes occurs because the gravitational well of the black hole swallows certain particles that poof into existence, while their alter-ego tends to escape. At least that’s my best understanding of it. The maths are way over my head too.

@CWOTUS The point of the exercise was to understand that the atmosphere is relatively thin and the number of molecules in a mole, Avogadro’s number, is huge 6.02×10^ 23. Also Nitrogen is quite stable in the N2 form while oxygen and hydrogen are reactive and combine readily with other elements.

But what is matter created from @ETpro?

All energy and matter was created during the Big Bang, it has been transformed and rearranged since then.

As for the individual elements, they are created when nuclear fusion inside stars combines certain elements to create others. This chart shows how helium can be created from hydrogen. A similar process created all of the elements.

I know how the elements were made. That’s a fairly easy concept to understand.
But what was the energy and matter created from in the Big Bang?

Nobody knows. The answer may indeed be nothing. It has been described as “one of the greatest unsolved problems in physics.”

I will stay tuned!

I’ve always really loved Neil DeGrasse Tyson’s The Most Astounding Fact for explaining the interconnectivity of the universe. I don’t think i’ve often heard science be put so poetically, and beautifully and full of awe and positivity for humanity.