PlasmaGryphon's Comments

I've never liked that quote, as it seems to add to the black magic nature people attribute to statistics. To me it is the same as saying there are lies, damned lies and big words. If you misuse a big word or statistics, it is either a regular lie or mistake. Otherwise at some point the onus is on reader to understand, look up, or realize they don't understand.
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Statistics is a very rigorous branch of mathematics. But at lower levels it is taught as if it were a bunch or oracles in black boxes that spit out answers. Learning where those tools come from can make their limits and uses much clearer. But without that knowledge, a fully well intentioned and honest researcher could get garbage out of a tool and not realize is the tool was inappropriate.

It is like giving someone a recipe vs. teaching them cooking techniques and ingredients. Things work fine if you have exactly what you need, but go awry if you need substitutes. Sometimes novices don't even realize they made a substitute. And there are the few special ones that will not realize they should sometimes peel a shrimp or remove the seeds from hot pepper, and then say the recipe is broken because that was not spelled out.
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I'm don't really understand why anyone would ask, "Why hold a music festival?" or, "Why would they use a gimmick to sell something?" Unless there is another why I am missing.
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Kind of funny they open with eggs as there was yet another major study in the news this week that too many eggs is connected to an increase in heart disease. At least from a cursory search through PubMed and some journals, now repeated a couple times over the years, to me it looks like research supports some sort of threshold model to eggs being bad. A few eggs a week is ok, more than several starts to have significant effects. Studies argue for the threshold being somewhere between 3-8 eggs a week.
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I was wondering if this was going to be about second sound, yet another odd property of superfluids. From what I remember, second sound might be specific to He4. The isotopes of helium behave differently when very cold, as having an odd number or even number of parts in certain cases can affect how an atom behaves in quantum mechanics.

In the superfluid helium, you basically end up with two components: one that acts like a normal fluid, and another part that has no viscosity and can essentially pass through itself. Boiling and normal convection stop when you get cold enough to go into that state, as the part without viscosity can carry heat from hot to cold very quickly and pass right through the other component.

Second sound comes somehow from the mixture of those two components, so a wave that changes the composition of the two also changes temperature, and you get a temperature wave. But it has been a long time since I took that class and I don't remember much of the details...
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The place I live is pretty high up and probably the favorite of every place I've lived before in many ways... But also feels crowded and is a struggle to afford even with a way above average salary.
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Some LCD screens change the backlight brightness based on what is on the screen, in the name of more contrast. On a screen with a mix of light and black parts, people would notice a mediocre black more than a dimming of the light parts, so less backlight looks better.
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Scientific glass blowing is a very small field from what I've seen. It used to be a lot bigger many decades ago. But common chemistry glassware products are now mass produced, including some nice modular systems, and physics uses a lot less glass, partially from standardized vacuum components. This leaves just the most custom parts, and sometimes a single shop can supply a whole region.

I tried to actually join an apprenticeship when I was in undergrad, but lost out to essentially a flip of a coin to another student. The glassblower took only a single apprentice every other year and the student would essentially have an extra class for the next 3-4 years. I've met two scientists over the years that did go through an apprenticeship, but neither ended up using it in their career (at least directly, there is a lot of value to knowing how things are made when designing stuff, even if you don't make it yourself). About all they did with it beyond a hobby was sell just enough glass "toys" to pay for their equipment.

The area I work in would probably have used a lot more custom glassware parts 50+ years ago. But the only thing I've gotten from a university glass shop is cut straight tubes because they were cheaper than going out of house and a lot more accurate than trying to do it myself. Modern ceramics and glass optics on the other hand are a different story.
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I think 300,000 Yen is closer to $2700 US.

For $1000-1500 you could just commission a fursuit maker to make an airbrushed cat head, possibly of higher quality...
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Your last paragraph is parallel to why the field I work in uses eV for temperature.

A select few special people get rather indignant if you mention that scientists use any non-SI units. It seems amusing some would pick that hill to die on.
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I rarely have had to know more than pi~3 for the vast majority of my work. 3.14 or 22/7 or 3+1/8 (what your binary works out to) is about the limit of what most people would need if doing multiplication with paper and pencil, or on a slide rule. Base 7 would be far better since the classic approximation 22/7 -> 3.1, but that seems penny wise pound foolish.

I find the obsession some have with memorizing pi a bit odd. Nothing wrong with it, but ultimately impractical. If someone were worried about the desert island scenario where they don't have access to a book, calculator or computer, I think they would be far more versatile with a bit of calculus, as you could then figure out how to calculate pi, do it once, and write it down.

As far as actual constants with units, they are arbitrary and you can change more than one of them to be convenient whenever you want. General relativity is commonly done with what we called theorist units, where c and G are set equal to one simply to avoid writing those lets in equations a lot (and suddenly time, distance, mass and energy are all now the same unit value...). Otherwise the updated SI just picks these values to be consistent with what we already use (including Avogadro's constant which will have an exact value).
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In my limited, biased personal experience, a lot of Americans have a rough idea of metric units (except maybe air temperature), but I've heard complaints from people from outside of North America about how it is simply impossible to convert units without a computer.

My issue with converting is not signage and labels, but screw threads. I use metric threads for most projects, but some still need imperial threads and I try not to mix. For example, 1/4-28 is used on vacuum parts, and I don't want an M6 anywhere near that. It is one thing to change a product over when it is stand alone and after market parts are willing to change for new models (e.g. for a car), but harder when you have to interface with existing equipment. Even then, there is a lot of science equipment that is spec'ed metric only, but comes only in 12.7 and 25.4 mm sizes.
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Some such effects get subtle or down right scary once used in marketing, especially ones that still work when you're fully aware of the effect. I wonder if these researchers still go out of their way for free food/coffee even when it isn't worth the time (a common occurrence I still miss from working at a university).
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Why does 99% of species being extinct mean evolution doesn't work? Wouldn't that mean the exact opposite?

This sounds equivalent to saying because 99% of restaurants that ever existed are out of business, therefore food trends don't exist and all restaurants opened the same year.
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Profile for PlasmaGryphon

  • Member Since 2013/02/01



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