Like, I think in terms of a musical instrument; if it’s played and played and played and played, over time it’ll get out of tune. And I would think the various physical “constants” of the universe would work in roughly the same way – over time, there’d be variations due to entropy. But, for example, the speed of light in a vacuum is constant, and continues to be constant. If entropy is an unavoidable aspect of our universe, shouldn’t it affect the speed of light in a vacuum too? Wouldn’t we expect to see some sort of slowdown or at least variation over time as a result of entropy?
In: 49
You misunderstand entropy. It is the simple fact that energy tends to spread out / even out over time. In context of matter, it may *appear* to be a force of chaos tearing things apart… but really it’s a force of order. The end result, barring any other forces, would eventually be perfect uniformity.
Anyway, a “physical constant” is not energy. Heat, light, electricity, matter… that’s all energy and they all adhere to entropy. A number is not energy. A number that describes core characteristics (speed of light in vacuum) or interactions (gravitational constant) are still not energy. Constant just means that they don’t change and why would they?
Example. Gravitational acceleration is Gm/r^2. Doesn’t matter if you can read that, point is number goes up slowly with more mass (m) and goes down very quickly with more distance (r). Entropy affecting mass or distance will change the acceleration, but it will not change the constant.
So what is G? Well, gravitational constant is the number left over because *our measurement systems are entirely arbitrary*. It would be possible to define measurements in such a way that the constant is 1, therefore not needed in the equation at all. But we can’t do that for every constant simultaneously so it’s completely pointless. If you can’t visualize that, search for a decimal to hexadecimal converter and try it out with random numbers. Recommend 102 (66) and 1234 (4D2).
I really want to hammer this point home. Let’s take a random pipe length 3.45ft. If you used it to apply a torque (ie using a car jack) at 42.16lbs you would be applying 145.452ft-lbs. Really messy number, right? Well, let’s define a new unit “pipe feet” where 1pft = 3.45ft. And a new unit “jack pounds” where 1jlbs = 42.16lbs. Well guess what? You applied a torque of EXACTLY 1pft-jlbs. The number is utterly meaningless but you can do this with whatever you want.
And yes we actually do this. 1AU = 150 million km. 1AU is the distance from earth to the sun. It is not bound to fundamental cosmic forces, it does not describe anything meaningful whatsoever… and therefore if you use it to calculate other things the numbers are going to be messy. What I want you to understand is that ALL units of measurement are like that. It is sheer randomness that we ended up with meters in the first place… which means utterly nothing in universal / natural law terms.
Ideally our numbers *would* be based in something meaningful but as it turns out that’s hard. Some countries were working on that recently, here’s the official definition of 1 second:
>One second is the time that elapses during 9,192,631,770 cycles of the radiation produced by the transition between two levels of the cesium-133 atom.
>It is the time required for an electromagnetic field to propagate 299,792,458 meters through a vacuum.
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