Why does thermodynamics laws look like a tautology ?
from A_A@lemmy.ca to nostupidquestions@lemmy.ca on 10 Sep 2023 14:45
https://lemmy.ca/post/5016031
from A_A@lemmy.ca to nostupidquestions@lemmy.ca on 10 Sep 2023 14:45
https://lemmy.ca/post/5016031
1^st^ law of thermodynamics :
There is something that will always be the same.
2^nd^ law of thermodynamics :
Everything else always changes and never will be what it was before.
#nostupidquestions
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A closed system is closed because all of the edges aren’t open.
I think you are misquoting the laws of thermodynamics.
en.m.wikipedia.org/wiki/Laws_of_thermodynamics
It’s very important to understand the rule and the implications. It’s self-consistent. They are axiomatic, so if you can come up with a better system that and demonstrate it you can beat it. But until then they’re laws.
My misquotation was on purpose.
in the same thread of thoughts : if there was a system without the first law, anything could appear as if by magic !
…that is, until the 1st law appears.
It sounds like you’re confused on what a natural law is. They do not prescribe the behavior of a system, they describe it.
The first law is a law because our observations state that all systems obey it, not the other way around.
What you’re saying is “If there was a system that behaves fundamentally differently than every system yet observed, then it would not follow the laws of thermodynamics.” Which is kind of the point.
I am trying to find a loophole for the origin of the big Bang or whatever created the universe.
P.S. What I’m saying could be something like : “if a system is empty it doesn’t contain the first law”.
To put it another way: These “laws” describe what we think is going on based upon human observations and testing.
The scientific method is our tool for figuring this stuff out, and “laws” are subject to change when we figure out or discover something we didn’t know before.
Just because something is a scientific law does not mean that it’s 100% correct and immutable for all time: It’s just our concept of what seems to be happening based on what we observe and what we think we know.
I think there must be a mechanism behind the (stated) laws. This is what interest my reflection.
Well, yeah, these laws describe what we think that mechanism is. It’s good that you have an interest in science! Don’t give up and keep learning :)
We don’t know that the universe was truly created. The concept of things being “created” is something us humans came up with (usually meaning existing atoms are shifted into place for us to then recognize them as a certain object).
We have never observed anything in the universe just popping into existence from nothing, so the least speculative theories assume that the universe did not either pop into existence from nothing.
We do have evidence for the Big Bang, but it’s not the creation of the universe, it’s rather just the expansion of space (and is still occurring today). Before the Big Bang, the universe must’ve taken place in a more contracted space, but we don’t know what that means in effect.
You could also apply our imprecise human definition of the universe being “created” to mean that everything existed beforehand and it just got shifted into the recognizable universe we know today. That is something the Big Bang did do. I’m really not a fan of that, though, since it obviously confuses people.
Here’s a video explaining the Big Bang in more detail: tilvids.com/w/9kRqDF9pXrDFprLiAG1hAr
(Unfortunately, the guy does talk of the universe being ‘created’ at the beginning of the video. Near the end is a more precise definition.)
Thanks for your time and attention.
if we did, that would be a major shift in physics. in this regards I heard of (or read of) two candidates :
.1 if universe’s expansion continues to accelerate, (it would mean) dark energy is increassing.
.2 an excess of hydrogen (clouds) outside of galaxies was observed that is difficult to explain with current cosmology.
I know these are not direct observation of something popping up, …but still.
Yeah, dark energy is an interesting theory. I certainly don’t understand enough about it to really be able to judge it, but it kind of feels like we’re following our human tendency again, to find someone/-thing to blame, without that really aiding the explanation…
On a side note :
is there something in nature that prescribes the conservation of energy ?
(please, if you answer this, do so under my other comment (big bang…) …I don’t want to lose track of the main topic).
Probably because wherever you got those definitions of the laws of thermodynamics is just wrong. If I assume it's your own paraphrasing of the laws then your understanding of what the laws mean is incredibly flawed
The 1st law discusses energy. The total energy contained within a system totally isolated from others will not gain or lose total energy, but it can be transferred between places or change forms.
The 2nd law discusses entropy. The total net entropy of systems in natural interactions always increases. This isn’t in contradiction to the 1st law, because the same net energy is there, but after any thermodynamic process, that energy just takes on a form that is more entropic than before.
These laws haven’t been “ordained” by anyone, just scientists’ best guesses for how the world works using our observations.
Setting aside for a moment your (purposeful?) mistaken rendition of 2 of the 4 Laws…
I like to characterize them this way:
These aren’t rules some entity has given us. As best we can determine, these just describe the way the universe works as regards energy. But instead of everyone having to discover them over and over or in every new proposed application, our Very Smart People have discovered them and recorded them.
I don’t see anything in there that’s along the lines of “this is true because it’s true.” The laws of thermo aren’t provable except by observation, because they are the first principles. If there were first principles from which we could derive the laws, those would be the laws.
That’s not to say they don’t exist, because they might. We just haven’t found them yet, if they do. I have gone through the mathematical foundation but I’m on the fence as to whether that counts as a “first principle” since it has a sort of “chicken & egg” problem.