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Comment Re:Can it decipher the Indus Valley script (Score 2) 99

That is what I was wondering. I'm betting the answer is "no". When you have very limited source material, and the correct translation of the source material is probably long lists of items like "3rd year, Nowhereville, 5 bushels wheat" I doubt this approach would get you anywhere.

In every case which I am aware of, (hieroglyphs, Linear B, Mayan) decypherment of ancient scripts required that a close relative of the script language was known to the decypherers. (If anyone has counter examples, I'd love to know about them.) If the language of the script is completely extinct, we may never be able to decypher it.

Comment "...defamatory, false, and malicious slander." (Score 1) 70

From GEMSA's cease and desist letter "... to write you in relation to the defamatory, false and malicious slander which you and Electronic Frontier Foundation made concerning our client..."

There really can only be one response:
"I resent that! Slander is spoken. In print, it's libel."

(In passing, I find it curious that they say "to write you" rather than "to write to you". Previously I've only seen the former construction from Americans, but this is an Australian law firm.)

Comment Matching trailers? (Score 1) 373

I can think of two extra features you'd like your trailer to have with one of these: cameras which talk to the tractor, and regenerative breaking. Some sort of trailer camera standard would be great whether the tractor is electric or ICE. If you're towing a standard trailer, do you need extra airbrake hardware, or does the trailer contain all of that?

Comment Re:If it's only 250 MPH, it won't be fastest. (Score 1) 373

Assuming you can get it there and you can build a really good road for it, it should go way faster than 250 on Mars, as there is much less air resistance, which is the main limiting factor for speed. However you'll die at the first corner because it will have the same momentum but only 1/3 the gravitational downforce (and little opportunity to use aerodynamic downforce) so it would look like a fish, move like a fish, steer like a cow.

Comment Re:Expansionism vs China (Score 1) 110

My criterion was world-dominant nations, and world domination tends to require expansion. I'm pacifist, so if you want to make a list of countries which achieved great influence without expansionism, I'd be happy to receive it.

20th C USA and 21st C China are (so far) not so much into expanding their borders, although they are into projecting military and economic power to influence other parts of the world to their advantage. (The non-expansionism is recent: 19th C USA was very much into expanding its borders, and 20th C China nabbed Tibet.)

I'm not sure I agree with your classification of Qin as non-expansionist.

Comment Country of the century (Score 1) 110

The 20th century was dominated by the USA. The 19th century was dominated by the United Kingdom. It looks rather likely (as demonstrated by this story) that the 21st century will be dominated by China. Can we find other nice clean examples?
I suggest:
16th century Spain (on the back of New World gold and silver)

Anything earlier than this is well short of global impact, due to lack of communications (particularly between the Americas and the rest of the world)
13th century Mongolia
8th century expansion of Islam
1st century BCE Rome
2nd century BCE Qin
3rd century BCE Macedonia

Comment Re:NTP because... (Score 3) 172

Until you start up the reactor, you just have uranium fuel (half life about 1 billion years), not lots of nasty highly radioactive stuff. If it fails on launch and the fuel is not contained you only have chemical heavy metal toxicity to worry about. I expect they can do a good job of containing the fuel in any case.

Once the reactor starts up, you are safely in orbit. The biggest danger would be on return from Mars to Earth orbit. You'd certainly want to design these things not to ever attempt reentry. It would take a lot going wrong to cause accidental reentry.

I'd want there to be a high quality risk assessment, but I think it wouldn't be hard to reduce the risk of atmospheric contamination to very low levels.

Comment Re:Spectacularly confused summary (Score 3, Interesting) 173

So if I happen to have a couple of charm or bottom Lambda bosons, I can do something clever to collide them and I can get energy. Alternatively, I could just wait about 10^-12 seconds until they decay of their own accord, and I can get energy.

It got past the Nature reviewers, so I suppose there must be some point, but I'm not seeing it.

Comment S process (Score 2) 109

I learned quite a bit about nucleosynthesis, but haven't revisited it in decades.

There are three main processes for synthesizing heavy elements. In the s-process (slow), neutrons are absorbed by heavy nuclei slowly enough that the nucleus has time to beta decay, if it is too neutron rich to be stable. The s-process happens in red giant stars, and the products can be released by stellar winds and planetary nebula formation.

In the r-process (rapid), neutrons are added very quickly to heavy nuclei, which absorb as many neutrons as they can and then, once the neutron bombardment ceases, beta decay back to stability. I don't recall whether we knew where the r-process happened when I was studying this, but this result would be r-process.

In the p-process (proton), nuclei grow by having protons added one at a time. This is presumed to happen in supernovae, and p-process nuclei are rare.

Isotopes coming from the s process will have abundances inversely proportional to their neutron cross section, because that cross section determines how quickly they move on. Also, while many isotopes can be produced by several of these processes, some can only be produced by one. My understanding is that these methods indicate that the s process is the predominant source of heavy elements. However this table (pointed out by other /. posters) contradicts my understanding, so possibly my knowledge has become outdated.

Can someone with more recent knowledge comment on how these new results can be reconciled with isotope abundances?

Comment Re:Why Lithium? (Score 4, Informative) 131

Battery chemistry is a hot topic and pretty much anything that shows promise is being researched by someone somewhere.
and those results are just for 2016-2017, and I didn't search for synonyms "Nickel", "Iron", "Zinc", "cell" (instead of "battery".)

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