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?
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Physical constants, like the speed of light in a vacuum, remain constant because they are not affected by local interactions or entropy in the same way ordinary matter is. These constants are more like the underlying structure of the instrument itself – they don’t change just because the instrument is being played.
The speed of light in a vacuum is a fundamental constant because it is a property of space and time in our universe. It’s not determined by local interactions of matter and energy; rather, it is a feature of the fabric of spacetime itself.
So, while entropy affects local systems and can lead to disorder, it doesn’t directly impact these fundamental constants because they are not dependent on the specific conditions of any one place or time in the universe. They remain constant, providing a stable framework within which the processes of entropy and change can occur.
Entropy is our rationalization of the concept that ordered things will trend toward a state of disorder over time if allowed to do so. Take a drop of blue dye and drop it in water. At first the water closest to the dye will be bluer than the distant water, but over time the dye will disperse across the water until the water is the same shade of blue throughout. This is the state of maximal disorder, where the dye and water are uniformily distributed.
Entropy is commonly considered to be synonymous with ‘chaos’, much to the detriment of those first trying to understand concept. Entropy is not the breakdown of rules, it is itself a rule of the universe. In fact, entropy is predictable, even measurable. Entropy would have no bearing on the speed of light, but it does on, for example, the dispersal of photons (small units of light) away from the point of origin into an open space.
The constants are only magic numbers because that’s all we know about them for now. They keep popping up all over in important places regardless of what else we are actually calculating.
Eventually we may find that they can be derived from something else, but it’s not clear if that’s true.
Entropy is unrelated, it’s basically just saying things get messy if you don’t put effort into cleaning them up. They might randomly become clean on their own but it’s so improbable you can ignore that.
I could be getting some details wrong since I’m not a physicist, just an interested layperson.
From what I understand, at a simplified level, entropy is the tendency of *stuff* toward disorder, where *stuff* is really just matter and energy – everything that’s physically tangible and has form or energy. It’s everything we can touch or see.
Universal constants are not matter, nor are they energy. They’re more like the framework that allows matter and energy to exist. Since they aren’t *stuff*, rather they are rules, intangible ideas like the concept of entropy itself, it’s not possible for them to break down or trend towards disorder. There’s no disorder that they can achieve – disorder is a property of matter and energy, not the rules upon which the universe depends.
In this context “disorder” isn’t the same idea as “chaos” or “randomness”. It’s more like “homogeneity”. Entropy says that if you have a concentrated bundle of stuff in a system, that stuff will eventually spread out to an average state. An average state is one that is less clumpy – no bundles of stuff, only a smooth homogeneous mixture. My favorite thing to think about here is stars. Once a star forms, it starts to spew energy all over the place, causing what was once clumpy (a star being a clump of matter and energy) to spread over a larger area – stars are entropy machines!
Now hopefully you can see that, because universal constants aren’t “stuff”, there is no way for them to spread out and become more homogeneous. The concept of what this would mean for a universal constant isn’t really well defined. Since it’s not stuff, it can’t become more homogeneous. There’s no “where” for a constant to “spread” to. There isn’t really any way that a constant or rule could become more disordered since it doesn’t have any order to begin with. It has no clumps, no way of becoming more average or more spread out. It’s just a single number – the average of a number is itself, and there is no direction or dimension in which it could spread out.
The important point is that disorder is more like homogeneity, not randomness or chaos. In order to become disordered, a thing must have form. Constants don’t have form.
Entropy is a statistical effect that makes a big difference when you have a large number of things (usually atoms or other atomic/subatomic particles)
If you only have one thing, entropy doesn’t really apply.
It’s a bit like how demographics doesn’t really apply to one man living on an island alone.
>But, for example, the speed of light in a vacuum is constant, and continues to be constant.
It is constant by definition (and only for inertial frames). If tomorrow Einstein v2 comes up with a completely different (but more empirically accurate theory) that doesn’t define it as constant, it won’t be.
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.
Paul Dirac had the same thought in 1937 🙂
https://en.m.wikipedia.org/wiki/Time-variation_of_fundamental_constants
Entropy is an emergent property. It exists because things move around following these laws that have these constants. There’s nothing in any of those laws that says entropy must increase. Every individual particle in a system can obey the same laws and become more ordered over time without violating any laws. The problem is that it’s extremely unlikely, infinitesimaly unlikely.
Take a room that’s nicely organized. Now randomize the positions of everything in the room. Now it’s disorganized, entropy has increased. Now randomize the positions of everything again, it’s still disorganized. It’s entirely possible that you can randomize everything back to where it belong and you have an organized room again, but there’s only 1 way the room is organized, and n! ways it’s disorganized, so you’re much more likely to get a disorganized state than an organized one.
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