puzzledobserver

Joined 7 years ago

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Comment · 1 month ago
Did you mean: > Only 12% of American male youth who are __not__ qualified for the military __are__ in college?

Without reading your citations, your argument threw me for a loop.

Comment · 1 month ago
In a theoretical sense, you are right.

The life of most currency notes is bank to customer to merchant to bank, and the bank could just track serial numbers to figure out your spending habits.

Practically, it would make little sense. The actual life of most currency notes is bank1 to customer to merchant to bank2, and there is a large probability that bank1 and bank2 are different entities. And then, so many more people use the credit card system, and it is so much easier to track people there, that the ROI on tracking people using cash would be low.

I would be very surprised if any bank tried to scan currency note serial numbers.

Comment · 2 months ago
I always thought that the Gettier problem was an academic curiosity.

Someone who justifiably holds beliefs about the eventual impact of AI that later turn out to be true---can they be declared to have been knowledgeable about the subject matter?

Comment · 4 months ago
Disclaimer: I'm not a physicist.

For a particle to "oscillate", it must "experience" time. All massless particles travel at the speed of light. As a consequence of special relativity, they don't "experience" time.

Therefore, neutrinos must be traveling slower than light, and they must have mass.

Comment · 7 months ago
Wikipedia tells me that the package index PyPI (launched in 2003) is about 4 years older than the interpreter PyPy (first released in 2007).

Still, at its core, PyPy is a Python interpreter which is itself written in Python and the name PyPy fittingly describes its technical design.

Comment · 1 year ago
Comment · 1 year ago
A natural follow-up to your question might be: "If everything is expanding, then wouldn't the ruler itself be expanding, so the expansion becomes unobservable?"

I'm not a physicist, but from my understanding, the situation is a bit more complicated than the phrasing in your question suggests.

Observation #1: The light from far-away galaxies is redshifted (spectral lines are a bit off from where we'd expect them to be). This suggests that these galaxies are moving away from us. The farther away the galaxy, the more it is redshifted. This suggests that the farther away the galaxy, the faster it is moving. Observations indicate that the recession speed is directly proportional to distance.

This observation is consistent with general relativity, which suggests an expanding universe with homogeneous mass.

But on a smaller scale, gravitational binding somehow takes over, and on even smaller scale, things like electromagnetic and nuclear interactions start having a greater impact, and that's why the Milky Way isn't itself expanding. For that matter, even Andromeda (0.8 Mpc) is too close to be affected by Hubble-style expansion, which only becomes observable at the multi-megaparsec scale.

Comment · 1 year ago
The Indian Supreme Court introduced the Basic Structure Doctrine in 1970, allowing the judiciary to overrule constitutional amendments if they are found to contradict the "basic structure" of the constitution.

It's original purpose, if I understand correctly, was to guarantee that fundamental rights were an essential part of the constitution and couldn't be amended away.

Wikipedia says that multiple countries appear to have adopted the principle: Pakistan, India, Bangladesh and Uganda.

Comment · 1 year ago
Could this lead to better semiconductor manufacturing? Increased yields, fewer defects, larger chips, etc.?
Comment · 1 year ago
It's also because making some of these decisions (choosing health insurance, deciding how much to save, etc.) involve two considerations---the first being purely analytic (mundane cost vs. probability of contracting major disease vs. cost of catastrophe) and the other being necessarily extra-analytic (how risk averse the individual is).

One can objectively reason through the first set of considerations, while the second involves a subjective element and is likely heavily influenced by their upbringing and life experiences.

Nobody knows how much to save or how much to spend on insurance. It's completely reasonable to seek advice, and one's parents might be a great starting point.

Comment · 1 year ago
It looks like the website is based in India.

Instead of the ones(10^0)-thousands(10^3)-millions(10^6)-billions(10^9)-... system followed in most other parts of the world, the Indian numbering system uses ones(10^0)-thousands(10^3)-lakhs(10^5)-crores(10^7)-...

So, for example, half a million subscribers (500,000) would translate to 5 lakh subscribers (5,00,000).

Comment · 1 year ago
If you ignore syntax and pretend that the following is a snippet of Java code, you can declare that a variable x always holds an int, like so:

var x: int = y + 5

Here x is the variable being defined, it is declared to hold values of type int, and its initial value is given by the term y + 5.

In many mainstream languages, types and terms live in distinct universes. One starts by asking whether types and terms are all that different. The first step in this direction of inquiry is what are called refinement types. With our imaginary syntax, you can write something like:

val x: { int | _ >= 0 } = y + 5

Once again, x is the variable being defined, it is declared to always hold a value of type int at all relevant instants in all executions, and that its initial value is given by the term y + 5. But we additionally promise that x will always hold a non-negative value, _ >= 0. For this to typecheck, the typechecker must somehow also confirm that y + 5 >= 0.

But anyway, we have added terms to the previously boring world of types. This allows you to do many things, like so:

val x: int = ... val y: int = ... val z: { int | _ >= x && _ >= y } = if x >= y then x else y

We not only declare that z is an integer, but also that it always holds a value that exceeds both x and y.

You asked for the type of a function that multiplies two numbers. The type would look weird, so let me show you an imaginary example of the type of a function that computes the maximum:

val f : (x : int) -> (y : int) -> { int | _ >= x && _ >= y } = ...

This doesn't really get you to the maximum, because f might be computing max(x, y) + 5, but it does show the idea.

The final step in this direction is what are called full-blown dependent types, where the line between types and terms is completely erased.

Comment · 1 year ago
Not really.

Or at least not completely extinct in South India. Some of my favorite childhood memories are from these messes (short for mess hall, I assume). You go there, pay what they ask, eat what they serve.

MTR, Brindavan on MG Road (though that's long gone), Iyer Mess in Malleshwaram.

What they lack in choice they usually make up for in taste.

You're right that they have a more traditional ambience and newer restaurants offer more choice, but they are definitely thriving in the parts of Bangalore that I grew up in.

Comment · 1 year ago
I agree that over-reliance on pictograms frequently causes confusion.

I remember reading an article some time ago about European vs North American traffic signs. The article was praising the European system that relies more heavily on icons over the North American system which is more text-heavy. I can't remember the details now, but I remember disagreeing vehemently with the article.

I find many of the traffic icons (particularly the ones indicating something about parking, stopping and one-way streets) very unintuitive. I strongly prefer the text-heavy signage that I see in the US.

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