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statistically speaking
You are [a] disembodied brain. You just came into being randomly out of the chaotic void
Your memory of your entire life also just came into being through a chance arrangement of particles
That includes your memory of that last statement and that one and that one
You my friend are a boltzmann brain
statistically speaking
Ludwig Boltzmann
Revolutionized physics in the latter half of the 19th century [his] most incredible insight was the kinetic theory of gases
He showed that the laws of thermodynamics
Can be explained by thinking of gas as a collection of microscopic particles in constant random motion
take entropy for example: prior to Boltzmann, Entropy was only understood as a measure of the proportion of energy in a system that
Can be used for useful work for example the hot dense gas in a recently fired engine piston
Only expands because it's surrounded by a colder less dense environment. The energy in that burning gasoline
Does the useful work of driving your car down the street, but if you put the compressed piston in an environment?
That's full of equally hot dense gas
Nothing happens. The gas in the piston still contains the same amount of energy
But it's useless energy. Why? Because in the latter case the gas inside the piston is in
thermal equilibrium with the gas outside the piston
Everything the same temperature and pressure
perfectly mixed
Entropy is a measure of how far from equilibrium a system is the lower the entropy the further from equilibrium
Any part of the universe left to its own devices always tends to flow back to equilibrium
That's the second law of thermodynamics right there
Entropy must always increase in a closed system
And it's that flow back to equilibrium that increase in entropy that can be harnessed to do work
But why does the universe have to return to equilibrium?
Why does Entropy always increase?
Boltzmann figured this out
Entropy is just a measure of the specialness or the degree of order in the current arrangement of positions and velocities
Of the system's particles, it's the proportion of possible states that are indistinguishable from the current state
Instead of an engine imagine a room full of air the air. The air molecules are moving randomly and over time they pass through all possible
Arrangements that they could have in most of those random arrangements the room is filled pretty evenly and we can't tell those
arrangements apart from each other
That's a high entropy situation because a high proportion of all possible states look just like this one
but in a tiny fraction of those possible distributions
All of the air molecules end up randomly bunched together in one corner
Or I don't know. Produce a density way of playing the ballad of serenity over and over
If you count up all the possible arrangements of particles only [a] tiny proportion
Do weird highly ordered stuff like that so they would be a low entropy situation.
Entropy increases because particle positions and velocities
get randomized over time
Boltzmann's interpretation of Entropy leads to a prediction that seems innocuous but has some astounding implications
his statistical interpretation
doesn't prohibit entropy from decreasing in fact it allows it.
For example tiny localized dips in entropy happen all the time when you get a chance
convergence of a few particles in one corner of the room
The larger the Random Dip in entropy the less probable it is but improbable isn't impossible
There's an Incredibly tiny chance
That all the particles in a room of gas will happen to all end up in one corner of the room
Due to their random motion. It would take vastly longer than the age of the universe for it to happen so in practice
We never observed the second law of thermodynamics being broken on macroscopic scales
But given infinite time any non impossible arrangement will happen
Imagine an infinitely large room a universe that's in perfect thermal equilibrium for infinite time
all sorts of dips in entropy will happen. Particles will occasionally converge into a dense environment like a black hole or a galaxy
Or Into a complex arrangement like a teapot or a box DVD set of the never made seasons two through eight of firefly.
All incredibly improbable
However, there's one arrangement that those particles could randomly fall into that will be even less probable than all the above
All the particles in a region much larger than our universe could randomly end up in almost the exact same location
Such an arrangement would give us the big bang
It's not known whether the big bang originated as a low entropy dip in an otherwise high Entropy universe
I mean, it may have, but however it happened
Entropy was extremely low at the instant of the big bang
And it's been increasing ever since the useful work performed by that increase in entropy
includes the formation of Galaxies Stars planets
Alan Tudyk
Indeed the entire process of evolution. In the far future the universe will reach
Maximum entropy the black holes will evaporate the last proton will decay and all of that cool stuff will cease
The universe will spend almost all of its time in that high Entropy state
Nonetheless it shouldn't really be so surprising that we observe a low entropy blip in an otherwise
Mostly high Entropy universe after all our existence is a byproduct of the universe's progression towards that high entropy state
What other time can we possibly observe? This is an application of the anthropic principle
We can only observe an environment capable of producing
Observers is not surprising that we view the universe from the comfy biosphere of a Terrestrial planet
even though the volume of all biospheres is
miniscule compared to the volume of the universe
Similarly we must have appeared at a time and in a universe
Capable of producing biospheres the anthropic principle may explain why we exist in monstrously improbable or rare?
circumstances
But the principle doesn't allow us to assume a circumstance for our existence. That is [anymore] improbable than is absolutely necessary
In fact, we're most likely to be in the most common most probable circumstance that could possibly explain our current experience
This is just Occam's razor or the law of parsimony don't add unnecessary complexity to your explanation
But it can also be thought of as an extension of the copernican principle
We observe the universe from as typical a vantage point as is consistent with our experience
So aren't there more probable smaller dips in entropy that could lead to conscious observers for example?
Why collapse a whole universe with the particles [a] single [galaxies] should be enough?
Such systems should massively outnumber larger big bang collapses
And so should the conscious observers that evolve in them
But we can go further
Why not just have particles converge directly into a single human brain in?
Exactly the right arrangement to have an illusion of memory and sensation that duplicate exactly our current experience
even if just for an [instance]
That would be a boltzmann brain
in a universe where structure results from Entropy fluctuations
The vast majority of Conscious experiences that ever occur should be Boltzmann Brains
Rather than ones that arise from say evolution it sounds ridiculous
But it's the logical conclusion if we assume a big bang from Entropy fluctuations
The hypothesis is also impossible to prove wrong
Every experiment. I do [may] [be] the randomly assembled
illusion of a Boltzmann brain that happened to come into existence
With the memory of trying to prove it isn't a Boltzmann brain
The hypothesis is unfalsifiable
But that alone may be enough reason to reject it
Sean Carroll has another nice argument against Boltzmann Brains
He says the idea is cognitively unstable by accepting that [we're] a Boltzmann brain
we're admitting to a state of fantastic Delusion and in doing so admitting our
incapacity to deduce our own nature
To expand on that we can also go back to parsimony and the copernican argument if we're Boltzmann brains
then we're the most common type of boltzmann Brain that has an experience that is indistinguishable from
this
So surely it's vastly simpler to accidentally manifest a brain with an Instantaneous
Delusion about its ability to understand the world in complex ways than it is to assemble one with true intelligence
That can trust its own conclusions
Conclude that you're a boltzmann brain and you must deny your capacity to reach that conclusion
This is [a] cute philosophical point however
I think the real interest in the idea of boltzmann brains is as a lesson in caution caution in arguing probabilities
Before really understanding the prior assumptions in this case
There's no evidence that the big bang arose from a random fluctuation
Pondering the cause of the extremely low entry big bang is probably more useful than wondering whether you existed a second ago
There's a similar idea for which we [should] also exercise caution. That's the idea that. We live in a simulation
It's been argued that simulated minds should be vastly more abundant than real minds
Or go where pokemons?
We're actually going to jump into that rabbit hole next time and it'll be with a very special guest
That's assuming
We don't blink out of existence in the next instant as momentary fluctuations in the [unit] [payoff] of [the] match
as a maximally and tropic
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