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Comment Re:Fifth force - Harrummpphhh! (Score 1) 240

You mean physics isn't finished yet!? Oh the horror!

Physics has always been "in a muddle", from the time before Newton, in the sense you assert since there has never been a time when we thought we understood it all.

There was a short time at the end of the 1800s when some made a silly claim that physics was complete, around 1888 when electromagnetic radiation was discovered. Except for the Ultraviolet Catastrophe prediction that all hot objects would radiate infinitely high frequency photons, and the photoelectric effect that had already been discovered in 1887 that could not be explained. And then new unexplained physics started showing up every couple of years in the 1890s. The non-existence of the ether shown in 1892, the discovery of X-rays, radioactivity, the electron, Curie's work showing that an enormous mysterious energy source existed inside the atom...

Comment Re:Higgs still there (Score 2) 240

...As for the latter: we still don't really know how dark matter works, and maybe it has its own forces (some oddball ones have been proposed).

And that is the motivation discussed in the cited paper, that this could be related to dark matter.

Asserting that we "know" that dark energy is a fifth force, in the same sense as the other four forces in the Standard Model, is claiming more than we actually know at this point. Maybe it is, but there are no good theories at this point that make it one, and it could be something quite different from the particle/force models physicists have been working with. Physics derived from the behavior of the Cosmological Constant in General Relativity may be some really new physics.

Comment One of the Best Showers I have Ever Seen (Score 1) 62

This was a superior shower, one of the best I have seen. I watched from the outskirts of Wrightwood, CA; elevation 1800 m just 20 km north of the Los Angeles basin but with an SQM 19.05 sky, a measure of sky darkness. due to mountain shielding of the light dome (the Milky Way is visible). This published list of darkness comparisons: rates this as "Typical for a suburb with widely spaced single-family homes.".

Starting at 12:40 a.m. (when I went out and started viewing) I saw 5 spectacular Earth-grazing fireballs leaving persistent glowing trails, with apparent colors of white, reddish, and greenish. In two hours of total viewing time, ending at 3:30 a.m. (I did some driving around testing different viewing sites), I saw 91 meteors, with the peak right at the end when the radiant in Perseus was high overhead, and it had hit about 80 meteors and hour in a 15 minute period.

Comment Re:Type 3s? (Score 3, Informative) 105

It would still give off the same total energy, shifted into the IR...or much lower. I wonder if they detected longer wavelengths.

I also wonder if thjs impacts the estimate for total number of galaxies at 100 billion.

Good questions.

No, this being a ground-based instrument, they could not look at the infrared wavelengths you are thinking of. The James Webb Telescope will be the perfect instrument to investigate this when it is launched in two years.

Yes this will gave some impact on estimated galaxy counts.

Comment Re: Unpasteurized milk production (Score 1) 258

there is such a thing as "good bacteria" but never mind, this process will kill it all. sterilizing away most of the nutritional benefit.

Because protein and calcium are unimportant sources of nutrition in milk? These are unaffected by pasteurization.

What "nutrients" are actually lost? Do tell.

Comment Re:Amazes me how much these scientists have missed (Score 2) 202

BMI is antiquated as a measure of health because it completely ignores body composition.

As a weight-lifter, I am very well aware of the limitations of the BMI since it declares everyone with a lot of muscle mass "overweight" or even "obese" even if their body-fat is in the low single digits.

But it is an excellent tool for studying populations, where the odd individual to whom it does not apply are averaged out of importance. This is what the BMI was developed for, and it is well proven in this role.

It is a useful tool for assessing the health status of most individuals also, but not everyone. Healthy weight increases with age, it is normal and healthier to carry somewhat more weight, but apparently there is no age-adjusted scale available, strangely enough. It is less accurate for very tall people (though an adjusted BMI scale is available for this). And it is useless for people will a lot of muscle mass, as I mentioned above.

It is annoying that most health advice sources ignore these caveats, or seem utterly unaware of them.

Comment Re:Rule of thumb (Score 4, Insightful) 622

The diamond ring and the family car are both 20th century inventions. I thought the rule was spending 52 weeks income on a car and 4 weeks income on a diamond ring. Now it's 21 weeks for a suburban necessity and 13 weeks for a shiny decoration. What strange priorities for a not so brave, new world.

Having a car as a 20th Century invention is rooted in the undeniable utility of having a vehicle that can transport people and goods long distances quickly.

The "requirement" that every marriage requires a large investment up-front in a diamond is purely the product of a marketing campaign by a diamond cartel (i.e. a price-fixing monopoly). Here is a brief, but honest as far as it goes, account by an organization dedicated to selling you diamonds. Note that the founding of the American Gem Society, in 1934, precisely coincides with the start of the De Beers cartel hard sell. It is striking that a trade organization, founded as part of a marketing scheme, does not try to hide its own origin.

Lengthier accounts of this bizarre pure luxury business are easy to find.

Regarding those "guidelines" (treated as "rules" by the industry) for how much to spend in a diamond ring - if you let marketing literature tell you what you should spend money on, you are perhaps typical, but still you are just being a patsy.

When I got married, no diamond was involved. It was a ridiculous waste of money, absolutely not an investment (they are virtually impossible to resell, the industry makes sure of that), and at that time a prop for the Apartheid regime. That last reason had ended, and recent "conflict diamond" rules have greatly reduced the tendency of diamond purchases to support mass murderers, but not ended that last problem entirely.

Comment Re:median vs average (Score 1) 622

As a statistician (well, once upon a time) let me say that the median is one of three averages. The averages are the median, the mean, and the mode. Each is an average with certain characteristics and areas of utility. If you've got a normal bell curve they are the same number.

For most purposes involving income the useful averages are the median or the mode. Not the mean, which is unduly influenced by extreme values. (I didn't read the article, so I'm only commenting on your response.)

Thanks, I have been peeved about this for a long time. The mean is the easiest to calculate (you only need to retain the total and the number of items), and for many purposes is the most useful (for budgeting for example). And so it is not surprising that in common, non-technical discourse "average" and "mean" are treated as identical.

But then we get the would-be pedants who introduce more technical and precise terms ("median" most often, "mode" is fairly uncommon) but continue to use the average=mean imprecise common terminology.

Again, not addressing the article.

Comment Re:median vs average (Score 3, Insightful) 622

Do the math.

Resale value varies a lot by car and by condition, but to have some numbers, lets look at a car that is worth 1/3rd it's upfront cost after 6 years, vs 10% after 10 years. The difference in depreciation is then 11% vs 9%, per year. If that were the only cost of car ownership, that would be significant - you could get a 20% better car by keeping it for 10 years instead of 6.

But other costs matter too. Maintenance (which does get worse over time), insurance, gas, parking, tolls, etc. So you're maybe looking at being able to get a 10% more expensive car at replacement time by keeping the car for 10 years rather than 6. That's not even a step up to the next model for most manufacturers.

So, for the same money, do you get better value by getting a $30k car every 6 years, or a $33k car every 10 years? Seems very subjective to me: if you value "newness", the former is a better deal, if you don't the latter, but it's a small enough difference either way.

What is a "20% better car"? Is there an objective absolute "car goodness" measurement scale I never heard of?

You seem so deeply embedded in the "car resale and buy new" paradigm that you cannot see that there is an entirely different way to manage you car needs. Buy a car and keep it on the road until such time that the repair costs are no longer economical when prorated over the additional mileage gained, or ti simply becomes too unreliable. I keep my car costs low by buying used (mostly, sometimes new) and then never selling the vehicle while it still runs, subject to the repair cost and reliability criteria just mentioned. "Resale value" is a piece of paper to me, I never resell until end of life.

But you are the source of the good deals on the used car market. Keep it up. I may buy your depreciated but perfectly serviceable car.

If you value "newness" you are absolutely going to spend big additional bucks over the years to satisfy this predilection. If you don't the difference is "not small either way" it is huge.

As you say, do the (real) math.

Comment Re:All hot air? (Score 1) 95

And the Chlorine and Bromine from sea water doesn't?

That's right it doesn't. It requires a special transport mechanism - like a completely chemically inert gas - to transport any chlorine or bromine up the ozonosphere, and then break up under ultraviolet exposure. The halogenated hydrocarbons that do this do not exist in nature. We created a transport mechanism where none existed naturally.

Keep asking questions, you will keep learning (as long as you heed the answers).

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