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    B Ideas to protect the Earth from possible asteroid impacts

    I imagine pretty much any type of asteroid has surface layer of dusty fractured regolith, similar to what Moon has. It does not transmit shocks well.
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    B Ideas to protect the Earth from possible asteroid impacts

    Completely negligible, considering the magnitude of catastrophe humanity is trying to prevent in this scenario.
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    B Ideas to protect the Earth from possible asteroid impacts

    Surface or near-surface blast may be preferable, it has a more predictable effect - part of asteroid is ablated away, pushing the entire remaining asteroid, still in one piece. Especially if you have even just an approximate control over the location of the blast and thus, the direction of the...
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    B Ideas to protect the Earth from possible asteroid impacts

    "Discovered" in that legislation means "orbit known with high precision". This means that positions of almost all hazardous 1+ km asteroids are already known for decades in advance.
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    US solar power generation for 2014-17

    What would be the cost of transporting it to the users? LOX is much cheaper than petrol, thus it is usually it is produced right at the use site. Needs only air and electricity. Yes. But ~30% conversion efficiency is a problem.
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    Oumuamua may be an alien lightsail?

    No, this wasn't the consensus. Interstellar objects were expected to be seen inevitably. A number of similar objects probably flew through our system undetected in the last ~200 years. As large survey telescopes become more numerous, we finally saw one.
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    Oumuamua may be an alien lightsail?

    Oh boy, *entire year* and we didn't see another one? I'm sure you know that in the last 400 years, this one is the first. Why are you surprised we didn't see two in 1 year timespan? Telescopes do improve, but not THAT fast. What are you talking about? Its behavior is explained quite well by a...
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    US solar power generation for 2014-17

    Well, the point was to recover stored energy. With unintended air liquefaction, that goal fails... IIRC what they do currently is they inject and burn a bit of natural gas in the compressed air just before it enters the turbine.
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    B Ideas to protect the Earth from possible asteroid impacts

    ?! The NASA Authorization Act of 2005 required the detection of 90 percent of NEOs of 140 meters (around 459 feet) or larger by 2020. Even though it seems that NASA will miss that tight target, the coverage of 1+ km sized objects is already better than 90%: https://cneos.jpl.nasa.gov/stats/...
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    B Ideas to protect the Earth from possible asteroid impacts

    Why this idea that "nukes wouldn't work" persists for so long? Try doing some back-of-envelope math. Nukes seem to work, unless we talk about 10+ km sized objects.
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    B Ideas to protect the Earth from possible asteroid impacts

    What are you talking about?? Moving either the Earth or the Moon by even a microscopic amount is totally beyond our capabilities in the next few thousands of years. Moving an asteroid is way more practical.
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    US solar power generation for 2014-17

    There are few other ideas (apart from ones in common use already, like hydro-storage). (1) Use excess electrical energy to synthesize fuel from easily available source materials (such as air or water). Burn this fuel at night. (On Mars, probably use "air" as a source? CO2 -> O2 + CO). Does not...
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    US solar power generation for 2014-17

    It does not work that great. Air gets hotter as it is compressed. Then it cools down in the cavern. Then it gets cold when it's expanded through a turbine. IIRC sometimes up to partially becoming liquid :/
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    US solar power generation for 2014-17

    Germany is a very densely populated country. There are no big sunny deserted places. Also, 47+ degrees northern latitude... not great insolation (most of the CONUS territory is more southerly than that!).
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    US solar power generation for 2014-17

    Tesla Powerpack is more appropriate product to consider for mass storage. 210 kWh per fridge-sized box. You'd need "only" 7.6 millions of those.
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    US solar power generation for 2014-17

    Solar utility scale generation growth 2014 to 2015: 24893 / 17691 = 1.407, or ~41% growth 2015 to 2016: 36054 / 24893 = 1.448, or ~45% growth 2016 to 2017: 53286 / 36054 = 1.477, or ~48%
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    Insights The Quantum Mystery of Wigner's Friend - Comments

    "The second assumption of FR is that there is only one outcome for a quantum measurement, so Xena doesn’t measure both heads and tails and send both versions of state s." Which sounds obviously false to me. We assume that Schrödinger's cat can indeed exist in superposition of states. IOW: the...
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    US solar power generation for 2014-17

    Solar generation results for US are out for 2017. Year over year: http://www.eia.gov/electricity/annual/html/epa_01_02.html https://www.eia.gov/electricity/annual/pdf/epa.pdf US: Net Generation (Thousand Megawatthours) 2014 Solar: 17691 (that's 0.43%) All sources: 4093606 US: Net Generation...
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    I "Surface" gravity of gas giants

    Note: the number of captured objects depends on many other factors as well, such as the density of asteroids/planetesimals crossing this planet's orbit, the size, density and longevity of protoplanet cloud when this planet was forming (this cloud was probably the most efficient capture...
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    I Core collapse of a supernova: the "void" left by the collapsed core?

    A stellar core of 1.5 solar mass star is larger that the Sun (not the core - the entire Sun)? I very much doubt it.
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    I Core collapse of a supernova: the "void" left by the collapsed core?

    Radius of the entire star is not what you need. Outer parts of the envelope are mere bystanders of the event. You need the radius of the *core* - only core is initially collapsing. It is about white-dwarf-sized - ~10000km radius.
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    I Core collapse of a supernova: the "void" left by the collapsed core?

    Thanks for the support/understanding my point. However, the inner part of envelope should be much closer to the newly formed NS - on the order of 10000 km instead of 400000 km - since only the core of the star is collapsing.
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    A Quantization isn't fundamental

    It did this for color force, here: Why the same should not apply to "the next next level" of gravitons?
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    A Quantization isn't fundamental

    This article's train of thought regarding 1/2 -> 1 -> 2 spin particles and their coupling leads to a prediction that graviton's coupling should be ~4 times stronger than color force. This is obviously not the case. Just observing that families of particles seem to "bifurcate" when we look at...
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    I Higgs potential shape meaning

    Field which isn't constant everywhere means you have "particles" of this field (perturbations of the field). When you look for a vacuum state, of course this shouldn't be the case. Therefore, yes, you assume that the field does take the same value everywhere in the vacuum. Modulo gauge...
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    B What would happen if the speed of light were different?

    You are right. ##\mu## is not the Higgs mass. Higgs mass is ##\sqrt {2}\mu##.
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    B What would happen if the speed of light were different?

    See ##\mu^2## in the definition of LH here in section "The Higgs mechanism": https://en.wikipedia.org/wiki/Mathematical_formulation_of_the_Standard_Model#The_Higgs_mechanism
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    B What would happen if the speed of light were different?

    That's different from this post: Here, you said that Higgs mass is emergent *in SM*. It is not. Higgs mass is a direct consequence of ##\mu^2## coefficient. I agree that SM may be supplanted by an extended theory without dimensionful parameters. Koide rule and other mass relations are signs...
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    B What would happen if the speed of light were different?

    Sure. They are related via ##\mu^2 = m_H^2/2 = \lambda v^2##. My point is that SM has one *dimensionful* parameter (while other 18+ parameters are all dimensionless).
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