sykh
Joined 8 years ago
Joined 8 years ago
The cardinality of the reals is called c. It is known to the be the same as the cardinality of the power set of the naturals. It is not known, in ZFC, which aleph this is. We just know that it is the same as the size of another set.
If you want to add an axiom and say that c is aleph1 then you are free to do so. But if you don't have this axiom then you don't know which aleph it is. So in what sense can you say that you know how many reals there are? You only know it if you add an axiom that says, "It is aleph1."
If I have a jar of pennies and I know it has the same number of pennies as the number of quarters in another jar that I have, does this mean I know how many pennies are in the jar?
I haven’t read the paper but I think the author is arguing that most real numbers don’t make sense physically. If sqrt(2) were shown to be normal and since it’s the hypotenuse of a right triangle of legs with length 1, I wonder what the author's response to this would be. Perhaps he’d say that such a triangle doesn’t exist physically.
Your premise is incorrect. The "sort of" part of my statement is important. There are lots of forces at play that cause this. I see it as sort of an emergent phenomenon and not the design of some clever genius or powerful organization.
Assuming we don’t want to live in a society in which vast numbers of elderly live in penury this isn’t true. It’s well known that when retirement savings are the responsibility of the emoloyee then they don’t save enough.
What you say about bad governance is certainly true and incompetent or badly incentivized leadership will exacerbate problems. I don’t know what the solution is for the U.S. but the current system is going to make us end up with a society with large numbers of destitute elderly. Shifting the onus to the employee via 401Ks is just kicking the can down the road so to speak. It also allows politicians and voters off the hook because the liabilities aren’t on the books. On paper it looks good but the reckoning will occur.
It seems, at first thought, unreasonable that people trying to kill themselves by jumping off a bridge would be more likely to regret the decision than people who shoot themselves in the head. I wonder if this is mostly a selective choosing of the survivors of jumping off the bridge to fit a narrative.
But a normal number has "random" digits in the sense that all finite sequences of digits (in a given base) occurs uniformly in the expansion. What other notion of random can one meaningfully give for an expansion of a number's digits? Without getting into too much philosophy.
From [1]: We call a real number b-normal if, qualitatively speaking, its base-b digits are “truly random.
My expertise is in commutative algebra so I'm outside of my comfort zone.
[1]: https://www.davidhbailey.com/dhbpapers/bcnormal.pdf