Theory of Information Could Resolve One of the Great Paradoxes of Cosmology 183
KentuckyFC writes: When physicists attempt to calculate the energy density of the universe from first principles, the number they come up using quantum mechanics is 10^94 g/cm^3 . And yet the observed energy density is about 10^-27 g/cm^3. In other words, our best theory of reality misses the mark by 120 orders of magnitude. Now one researcher says the paradox can be resolved by considering the information content of the universe. Specifying the location of the 10^25 stars in the visible universe to an accuracy of 10 cubic kilometers requires some 10^93 bits. And using Landauer's principle to calculate the energy associated with all these bits gives an energy density of about 10^-30 g/cm^3. That's not a bad first principles result. But if the location has to be specified to the Planck length, then the energy density is about 117 orders of magnitude larger. In other words, the nature of information should lie at the heart of our best theory of reality, not quantum mechanics.
Numerology (Score:5, Insightful)
Why, for instance, 10 cubic-kilometer voxels? Why not 100, or 1, or 0.1? How about 10^{15} cubic kilometers, which is about the volume of the sun? Adjust this number correctly, and you can match any energy density you want.
This is the problem with the science blogosphere: they'll take any press release whatsoever and echo it around regardless of whether or not it makes any fucking sense at all.
Re: Numerology (Score:5, Interesting)
The idea does actually work if the assumption is that we are living in a simulation, similar to ours. ;)
Re: Numerology (Score:5, Interesting)
The idea does actually work if the assumption is that we are living in a simulation, similar to ours. ;)
That's actually what I thought too. I've actually pondered this before. If we are in a simulation then stuff at the microscopic
or macroscopic only has to exist when viewed and can be generalized to a much lower resolution the rest of the time which
would greatly reduce the processing power required. This might also help explain some of the observation effects of quantum
physics where it seems that things act differently when observed.
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Re: Numerology (Score:1)
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A collapse is the same as taking a single statistically random sample from a probability distribution given by the wave function.
This is wrong: the complex amplitude collapses, not just the probability (which is the square of the amplitude, and contains less information). This distinction is the heart of what makes quantum mechanics intrinsically different from classical physics.
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To be clear, I (parent AC) wasn't saying that the probability distribution is the wave function, just that it is given by it (which you confirm, it is the square of the amplitude). Now consider you make an observation and collapse the system to a single state. This state had a certain probability of occurring (again, given by the wave function). If you try to measure again, you will get the same state.
Only if you don't observe any orthogonal characteristics in the meantime. Consider a two-state system, with eigenstates |a> and |b> (for example, z-spin). Now consider an orthogonal basis |1> and |2> (for example, x-spin) which spans the same Hilbert space, such that
|1> = 1/\srqrt{2} |a> + 1/\sqrt{2} |b>
|2> = 1/\sqrt{2} |a> - 1/\sqrt{2} |b>
Now, suppose we observe the system to be in state |a>. Then if we perform an observation in the orthogonal basis, we will have a 50% prob
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The idea does actually work if the assumption is that we are living in a simulation, similar to ours. ;)
That's actually what I thought too. I've actually pondered this before. If we are in a simulation then stuff at the microscopic
or macroscopic only has to exist when viewed and can be generalized to a much lower resolution the rest of the time which
would greatly reduce the processing power required. This might also help explain some of the observation effects of quantum
physics where it seems that things act differently when observed.
No, you can't generalize to a low resolution case most of the time because the resulting computed "frames" would begin to deviate immediately from any form of calculation you try to apply. Chaos and all that.
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Depends on what's simplified. I could imagine stars that were represented by a collection of variables, such that the difference can't be perceived by any current instrument. As the instruments improve, more detail is used on local stars. Back in Greek times, stars were simple, having position, proper motion, spectrum, and magnitude (which could be fixed or varying). When people got instruments that could tell more about stars, the simulators plugged in more detail, keeping it completely compatible wit
Re: Numerology (Score:5, Insightful)
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A completely bogus concept can be very accurately modeled with math. Reality doesn't care.
Ah! But according to Landauer's principle [wikipedia.org], reality *DOES* care.
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Landauer's principle rests on the Second Law, which itself rests on Kelvin's ego. The same ego that proclaimed heavier than air machine flight to be impossible. In other words, the second law is a conclusion without proof.
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Except that "math" itself is a human construct and has no connection to reality. We developed math purely from an observational perspective (Hey I have two apples. If I get two more, I have four.) of patterns we noticed, and expanded it from there using rules that we made up. Math itself is mostly self-consistent, but that's because we built it that way. There is no reason or evidence to suggest that the universe operates in any way that correlates directly to our mathematics, or even that our mathematical
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There is no reason or evidence to suggest that the universe operates in any way that correlates directly to our mathematics
I agree that there is no reason. But there is plenty of evidence.
Plenty of Evidence (Score:5, Insightful)
There is no reason or evidence to suggest that the universe operates in any way that correlates directly to our mathematics
Actually there is a lot of evidence that the universe operates in a way that correlates directly with mathematics. Using our mathematical models of fundamental physics we used them to predict the existence of a new particle, the Higgs boson, to solve the flaws in the model. Similarly the same principle applied to the discovery of quarks and the W and Z bosons before.
The fact that we can use mathematical models of the fundamental nature of the universe so incredibly successfully to predict new fundamental phenomena that we have never seen before is clear evidence that the universe does work in a manner that correlates with our mathematics. Indeed I would say that this is one of the truly remarkable things about the fundamental nature of the universe: we can construct mathematical models of it which agree perfectly within our, admittedly limited, ability to test them.
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The use of "perfectly" indicates how strong your faith is. Epicycles "perfectly" predicted planetary motion, thus math underlies everything, and orbits are circular because circles are perfect! Oh wait...
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Possibly, but if we're in a "game of life" type situation where the universe pauses, all the positions
are updated, and then the next cycle begins, we would never be able to observe it as it just means
that a "cycle" takes longer. This "cycle" could take 1 minute or 100 years but being inside the
simulation we have no way of observing actual time and therefore have no idea how long it takes
to go from moment to moment.
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Having to apply an arbitrary fudge factor to a calculation just screams BS.
Also, who says that the universe, at some point, isn't analog, or at least multi-state instead of binary.
Crap "science" based on a series of crap assumptions. Using the same technique (using arbitrary values and assumptions) we can "prove" that the dark matter is magic jelly beans.
Re: Numerology (Score:4, Insightful)
Fun fact: Everything you know is predicated on some set of assumptions.
Re: Numerology (Score:5, Funny)
Fun fact: Everything you know is predicated on some set of assumptions.
You're just assuming that's true :-)
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What about the trustworthiness of your own senses? What about the idea that our universe is an inherently logical and rule-following one?
You cannot "prove" those. You cannot even prove that everything out of your perceptive range continues to exist for the time that you cannot perceive it. Heck, one cant even really prove that their entire experience is not a simulation or dream.
These are all assumptions, not axioms; they cannot be proven, and must be accepted.
But more than that, I would wager that you w
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You cannot even prove that everything out of your perceptive range continues to exist for the time that you cannot perceive it.
So that crazy old guy who came up behind me and whacked me on the head with a rake (I was picking up my dog poop on public property, but he hates dogs) didn't exist until the rake hit me? And after the cops took him away he went back to fairytale land?
This is proof that objects don't have to be perceived by you to be real. Any argument that tries to work around that requires so many absurd assumptions that it's just not worth it.
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Re: Numerology (Score:1)
The first time we stumbled upon pi or any one of the constants, they were also just arbitrary numbers.
But sure, it's way too premature to be making any sort of publications about analysis like this.
If this value starts popping up when doing various unrelated research, it may warrant a closer look.
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Pi is easily proven to be valid by observation and measurement. It wasn't invented, it's a description of what people had already observed.
Same with the speed of light in a vacuum.
This number has no physical manifestation - it's an unfalsifiable claim [logicallyfallacious.com]. There is absolutely no evidence, nor any way of testing, this "theory." We could just as well say that the dark matter is all magic pixie dust - magic because it can't be detected even though it has mass (an undetectable mass? can't happen).
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That's complete nonsense. Either a constant is;
- static --> constant or
- dynamic --> variable
A constant divided by another constant is _still_ a _single_ constant.
Vi is simply trolling people.
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A circle is the set of points in a plane equidistant from a fixed point. That distance is called the radius. The perimeter of the circle is the circumference. The circle constant should be th
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If you don't like the extra 2, then use Tau. It is not like you don't have a choice.
> Using the diameter is one of the biggest blunders in the history of mathematics.
Equations are statements of facts. Projecting your _opinion_ and _emotions_ onto them doesn't change the truth about them.
First, you argue that the superfluous 2 ...
... is sloppy. Now you arguing it is a blunder to use the simpler ...
C = Pi * D
So which is it? Sl
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Nice!
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Ah, you're not an old FORTRAN programmer. Often, small integers would be stored in memory locations (I don't know exactly why). If you passed a constant to a subroutine that passed it to another subroutine that changed it, you could change 4 so it was now 5. If you assigned the constant to a variable in the first place, the variable would be changed by the third subroutine, but that wouldn't change the underlying number. Hence, constants were dynamic.
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You can actually do the same thing in Python.
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Sorry, I don't use old broken languages that pass everything reference, whether you want it or not.
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By the same logic observed energy density is not "real" either. We who live inside the universe are those observing both star positions (actually how definite their position is)
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Re:Numerology (Score:4, Informative)
Why, for instance, 10 cubic-kilometer voxels? Why not 100, or 1, or 0.1? How about 10^{15} cubic kilometers, which is about the volume of the sun? Adjust this number correctly, and you can match any energy density you want.
This is the problem with the science blogosphere: they'll take any press release whatsoever and echo it around regardless of whether or not it makes any fucking sense at all.
No, they are basing it on Plank Length: http://en.wikipedia.org/wiki/P... [wikipedia.org]
A unit of measure derived specifically from universal constants, the speed of light, the Planck constant, and the gravitational constant.
So it's not some arbitrary unit of measure as you suggest. It's the universes unit of measure. (assuming our current model of the universe holds) It's the smallest unit of measure that has any meaning in the real world.
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Specifying the location of the 10^25 stars in the visible universe to an accuracy of 10 cubic kilometers...gives an energy density of about 10^-30 g/cm^3. ...But if the location has to be specified to the Planck length, then the energy density is about 117 orders of magnitude larger.
So they roughly recover the quantum mechanical (apparently incorrect) result if they use Planck length^3 voxels.
Not that I read the article of course, but this seems an odd thing to do, as you should probably be confining them to hbar units of phase-space, not just confining them to voxels.
Re:Numerology (Score:4, Interesting)
It makes a tiny bit of sense to me.
"If we use [unstated first principles] to estimate what energy density should be, it's about 10^94 g/cm^3.
If we use the information content at the Planck scale, it's pretty close -- about 10^90 g/cm^3.
But we actually observe an information density of about 10^-27 g/cm^3.
And if we decrease the resolution from Planck scale voxels to 10 km^3 voxels, we get an information density that equates to 10^-27 g/cm^3.
This is evidence that we are living in a simulation, and the programmers aren't running the universe at Planck scale voxels, but only star sized voxels."
A large mountain of salt needs to be taken with this argument, but it does make sense -- as an argument.
Re:Numerology (Score:5, Insightful)
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Not that I read the article of course, but this seems an odd thing to do
Most slashdotters seem to agree with you, for pretty much any article :-)
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Another approach is to suppose that relative to a single point of space we try to nail down the position of everything we can see to as accurately as we can. We're going to have more trouble nailing down the position of distant locations because it's harder to build out a sensory network to triangulate positions or launch retroreflectors to everythin
Re:Numerology (Score:5, Informative)
IANAP but it still smacks of numerology because the paper does not make any basis for why the mass of stars is important in any way. There is plenty of ordinary matter not in stars, black holes etc. what would have caught my attention is if it made a case based on mass and not just stars. Or at least gave a relevant basis for why it is negligible to discard non-star matter.
tl:dr numerology. Though props to the author for saying it can be easily dismissed as numerology in his own paper - that's good scientific method.
Re:Numerology (Score:5, Insightful)
Is it just me, or does all this math wrangling seem like what Geocentric scientists were doing to properly figure out the path of stars in our night sky to align with their theory?
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> It's the smallest unit of measure that has any meaning in the real world.
That's actually an open question in Science.
We _assume_ that because we can't _actually_ measure anything smaller then the Planck meter (at this time with our current technology.)
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:-) -- My caricature of Muhammad. Please don't kill me.
How about this?
oO:-|>>
Is that enough to be blasphemy?
Re:Numerology (Score:5, Interesting)
Why, for instance, 10 cubic-kilometer voxels? Why not 100, or 1, or 0.1? How about 10^{15} cubic kilometers, which is about the volume of the sun? Adjust this number correctly, and you can match any energy density you want.
Fundamentally, you can't model the universe as voxels in the first place. The Holographic principle, [wikipedia.org] or at least the part about maximum information density, seems quite solid. There's a maximum entropy available in a volume (and thus a maximum amount of information needed to describe that volume) that's proportional to surface area, not volume. The number is absurdly high, well over 10^100 per square meter, but for extremely large volumes the cube/square effect starts making that limit meaningful. And that limit always prevents you from using voxels of the "natural" size of one cubic Planck length - the precision we know can model everything.
Perhaps the 10 cubic-kilometer voxels are reasoned from the limit for the visible universe? Still sounds high, even for that volume, and the visible universe seems like an arbitrary boundary.
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that said the 10km cubes come from the free energy associated with representing a classical definate spatial location of all th
So the Universe is Shrinking? (Score:5, Funny)
Need to consider this (Score:3)
What if the universe is 120 times larger? Maybe our part of the observable universe just looks like it happened from a Big Bang.
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What if the universe is 120 times larger? Maybe our part of the observable universe just looks like it happened from a Big Bang.
Well, actually, the universe is infinite in all directions according most. They're basing their math here on a given volume, "The observable universe" which, makes sense given how relativity works. You know, it's the whole cat paradox. If you cannot observe it, it does not exist, etc...
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Shrinking Horizon (Score:2)
Each second we can see another 186 thousand miles, revealing new 'observable universe'.
Actually that is not quite true. The size of the universe that we can see is actually shrinking. This very counterintuitive result is due to the fact that the universe's expansion is accelerating due to Dark Energy. Hence a distant point in space that is currently moving away from us very close to the speed of light today due to the expansion of space will actually be moving away from us faster than the speed of light tomorrow and so will become causally disconnected from us. So with time our horizon will
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It's not 120 times. It's 120 orders of magnitude or 1,000,000,000, 000,000,000,000,000,000,000, 000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000, 000,000,000,000,000,000,000, 000,000,000,000,000,000,000.
(the spaces are to get past the lameness filter)
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What if the universe is 120 times larger? Maybe our part of the observable universe just looks like it happened from a Big Bang.
For all we know our universe is just the latest in a string of "detonations" due to a locus of instability in the omniverse, Think of it like ripples in water caused by a drop falling into it. Each drop (the "bang") creates a universe and the resulting "wave" pushes the preceding bangs outward, causing expansion. Simultaneously all other bangs are hidden by the peaks of the wave since they all reside in the troughs.
The waves in this case would represent a multi-dimensional "buckling" as result of the explos
First principles? (Score:2)
Error 500, Error 404, (Score:1)
Is it just me? slashdot seems to be very broken right now
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...I actually had a relevant thing to post but slashdot lost it.
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Sincerely, Slashdot
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You'd think someone who can reverse entropy could keep a damn website up...
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It was broken for me for a minute or two.
Also, once in a while I've been getting SSL certificate errors regarding ./ from Chrome.
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At times, everything but the front page is being served by a third-party CDN, by the looks of it. When that happens, you get "logged out", and content pages fail with certificate errors because they're not coming from slashdot.org but a cdn domain.
Either slashdot are under attack and keeping quiet, or they're falling over and keeping quiet.
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My hunch is attack, since slashdot is a tech site it would be nice if they actually told us what is going on.
And if it is an attack, then is it business or pleasure? Lame either way.
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Is that because you can or you cannot read the fine articles?
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Reality is a configuration space (Score:1)
To start with, I should point out that I am far from knowledgeable on these topics. I took physics in college, but my degrees are in math and CS.
But I've been reading a little on cosmology, QM and speculations about where our understanding is headed, and it's occurred to me (probably because one of the books I read suggested it; I don't recall) that a plausible explanation for observed reality may be that matter and energy are merely configurations of an underlying "substance": spacetime. Or, if you're a
Scientists in the Wonderland (Score:2, Interesting)
"Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality." - Nikola Tesla
"The scientists from Franklin to Morse were clear thinkers and did not produce erroneous theories. The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane" - Nikola Tesla
"There is not self containing theory possible aside from pra
Re: Scientists in the Wonderland (Score:5, Insightful)
Sounds like a bunch of philistine engineers to me. Armstrong's quote could easily be applied to Einstein or Maxwell. Heaviside probably would have condemned the Manhattan Project as a bunch of theorists.
It's telling that Tesla draws the line at Morse, who invented Tesla's chosen field of engineering. And Tesla was a brilliant engineer. But later, as an actual scientist and researcher, as someone that had to do experiments and develop new theory, Tesla was a failure. His work was a dead end.
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I've read Tesla's Colorado Springs Notes, he spent years, essentially, inventing magic tricks. Academic citations of his work from this period are non-existent. It was a waste.
Heaviside was a genius and made some of the all-time greatest contributions to mathematical physics. He was also an eccentric loner who went mad in his old age.
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The greats -- Newton, Poincare, Einstein, James Clerk Maxwell -- were intuitive.
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- Pedro Ferreira's "The Perfect Theory"
And of course Newton had to invent the math to do his thing. Translation: he conceived of it first, then created the math for it second.
And Poincare... (Score:2)
resonance.is (Score:1)
The Universe is a simulation (Score:2)
The simulation hypothesis contends that reality is in fact a simulation (most likely a computer simulation), of which we, the simulants are totally unaware. [wikipedia.org]
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If we are unaware, then how do we have a hypothesis?
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The concept of "simulation" still requires a reality in which simulation occurs. If nothing exists outside the simulation it's not, in any meaningful sense, a simulation. It's just reality. Also, those who experience a simulation exist outside of it. There is no experiencing of the weather going on within your computer simulation of the weather - although you could do some sort of immersive VR and experience it. But that's because you're in the world it's being simulated from, and do not owe your own existe
High school physics back of a napkin calculation (Score:2)
Color me unimpressed. While somewhat original the whole approach is completely flawed. There are many more things than just stars in the universe. After all, for all we know, the visible universe only makes up a small portion of all matter [space.com].
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Tens of thousands of "Doctors of Philosophy" and just as many historians would disagree with you.
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Then again, I'm a doctor of philosophy and I agree with the original poster.
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I also have a PhD, in physics, and I disagree with the original poster. There are many others that would disagree too. And some of those that agree with such sentiment seem to be confusing the "what counts with science" with "what science is of reasonable importance to follow through on." It seems a lot easier to for some to just dismiss something as unscientific versus arguing it seems unlikely to be fruitful even if technically fitting in fine with the whole real scientific method of proposing new idea
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Considering that the scientific method was created as a philosophical methodology, I don't find that odd at all. As long as the philosophers keep themselves from going into religious or theological thought then it should be okay (as I wobble my hand and grimace). Remember, there were no scientists prior to the modern concepts of science. Everyone before that was pretty much a philosopher or alchemist of some kind. Heck, even during the Enlightenment period, those who delved into scientific research often sp
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Except creativity keeps creating more possible states, therefore more information. New words are created from thought alone.
Re:"to an accuracy of 10 cubic kilometers" (Score:5, Insightful)
Exactly. When they plug in an accuracy that makes more sense, all of a sudden they are 117 orders of magnitude off. In other words, they could have gotten any result they wanted by just picking some arbitrary value for the accuracy. "How much do we need the result to be? OK, then let's pick... 10 cubic kilometers. Because the universe really cares about round units based on the circumference of some arbitrary planet in some arbitrary milky way. See, only three orders of magnitude off, our theory is now better than quantum physics!"
Next month, they'l publish a new paper in which they have refined their theory by taking an accuracy of 0.71 cubic km. There, our refined theory now exactly predicts the correct density of the universe, from first principles! Throw away quantum mechanics, information theory is clearly superior!
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Actually the accuracy depends on whether Schroedinger's cat lives.
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Is that lipstick makes a woman look hot, but it's kind of gross when you actually kiss them.
Obligatory [rifftrax.com]
A problem most of us here will never know.
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Hmmm, maybe not Benford. Nothing in his bibliography strikes a resonant tone. I'll have to fish it off the shelf (I remember feeling somewhat conflicted between the writer's reputation and my lack of engagement with the characters, scenario and underlying re-building of the law