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Comment Re:String theory like saying algorithm is O(n^a^b^ (Score 1) 387

I think the problem is that by the very nature of it, it can't produce falsifiable predictions (if I'm understanding the arguments correctly). If a beautiful string-theory framework could produce something that COULD produce a falsifiable prediction, I think everyone would be super-happy, but I don't think it can do that either - at least I don't think anyone has successfully demonstrated anything like that.

It been more than 40 years and nobody seems to have done that. Compare that with any number of other 'beautiful frameworks' that produced falsifiable predictions (e.g. Relativity (both Special and General)). Even the weird stuff has often produced falsifiable predictions.

I'm not even sure what string-theorists think the end-game is. Do they actually believe they will discover some new theory of everything? Or have they given up?

Comment String theory like saying algorithm is O(n^a^b^c) (Score 1) 387

A theory that can't predict anything, that has an automatic 'out' seems pathological. String theorists may point out that they have proven that there are only so many consistent parameters for their theories, but it still seems there are no falsifiable predictions.

It's like someone saying the time-complexity of an algorithm is O(m^a^b^c). You then say - wtf? and they say 'Great news, we've proved that c can only be between 9 and13!. You then say integers? and they say 'Uh, NOOOOOO you idiot, obviously they are rational numbers. Did you know that c=9 7/13 has some fascinating characteristics!. So you then say what about a, b and c and they say 'rational numbers between 4-8'... we think.

Submission + - Help Save Arecibo Observatory, World's Largest Operating Single-Dish Observatory (whitehouse.gov) 1

earth2allie writes: The National Science Foundation has recently discussed the possibility of closing the Arecibo Observatory (http://www.scientificamerican.com/article/world-s-largest-radio-telescope-faces-a-troubling-future/). This facility is used for ground-breaking research in the fields of Radio Astronomy, Aeronomy, and Planetary Astronomy. As an astronomer myself I can tell you it is truly one of its kind, and the Arecibo community is asking everyone to take action by signing the petition to keep it open. Help us save Arecibo!

Comment Game Changer; Best-defense? Nuke your own airspace (Score 2) 208

This is great for defense. Unlike some people have said, you don't need to physically destroy the entire missile engaging you. For IR heat-seekers, you just have to blind the seeker. For radar guided missiles, deform the radome. Missiles tend to travel at high speeds, if you can screw up the radome or any part of the structure sufficiently it'll make a big difference to the attacking missiles pk (probability of a kill).

Your same offensive weapon makes an awesome countermeasure against HOBS (High-Off-Boresight) stuff that someone might launch using a HMCS (Helmet Mounted Cueing System). If you have decent secure networking, there's no reason why a bunch of your team couldn't target the same target too. So instead of being hit by one laser, you hit the target with N lasers. The enemy having better kinematics becomes moot too. A rotating mirror can rotate much faster than even the most maneuverable airframe.

The best countermeasure to this stuff if you don't have equivalent stealth? It's tough. You can't detect attackers well enough to get a firing-solution, you have nothing on your warning receivers for your team. Best case, let's say you know somethings up there due to VHF radar. So you send up your stuff, and all of them just get swatted from the sky. You ask your best engineers what to do about it, and they say 'Our best idea is to make the environment so nasty we deny the enemy access'. How do you do that? Nuke your own airspace. If you can't see the enemy but your assets start exploding, fire off a pile of SAMS (in nice solid reflective casings, no fine guidance necessary) and nuke your own the airspace.

If they are at altitude then that's one thing (not much fallout). If they are using terrain shadowing / strike teams going in to take out your ground assets, then you are talking about basically carpeting yourself with fallout.

Comment "Progressives" who don't believe in democracy. (Score 1) 387

It's fascinating to me how many people who purport to believe in democracyare so keen to strip others rights the second the front-runners don't fit their views.

At least the right leaning people seem to admit what they want (less government, less taxes, leave me alone, less intervention). Yet many of the left-leaning "progressives" are in such a state of double-think they don't even realize they are sprouting propaganda.

Just the term "progressive" is propaganda. Being "progressive" about denying others their rights when the views don't align with their own is NOT progressive. It's repressive.

Comment Re:Artillery versus Airplanes (Score 1) 206

Thanks for sending that. I was thinking a little about Plumbbob and the steel-plate as I typed the Orion comment, but hadn't heard of Wang Bullet. It has all the advantages of artillery and NPP combined. Plus the reaction mass (steam) reduces the acceleration. It's awesome.

 

Comment Artillery versus Airplanes (Score 1) 206

That's the analogy to think about with this. When is it best to use the artillery approach, and when is it best to use an airplane approach. An airplane approach implies refueling and re-use. You can amortize investments to improve capabilities over time. Artillery is all about cheap getting payload up there.

If you really want to get pure mass to LEO cheaply - it's hard to beat big artillery with a rocket stage. It has a few issues though.
Your payload has to be able to handle the G's from firing. The payload is probably fairly small unless you build a really big gun. If you are interested - google Gerald Bull.

Another cheapish way to get lots of mass to orbit that is mostly politically acceptable would be *really* big rockets. Some of the plans for humungous solid rocket boosters etc. Big diameter solid rockets are hard to beat for cost if you are going to throw it all away.

The truth is it's a continuum. You can plot this stuff on a graph and it's very informative. You discover the above. Artillery to LEO is very cheap - but limits you to tiny payloads. Massive throw away solids are cheap too, but if the launch vehicle fails you lose a lot. For things you value a lot (like people) you may not want to use a huge solid.

If you want to launch truly huge amounts of stuff to orbit it's very difficult to beat Orion and nuclear pulse propulsion. Politically the only way you'd see that happen would be to save the planet.

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