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It takes 6 months or longer if you use a low-thrust solution such as ion propulsion or solar sails. It took SMART-1 over a year to get to lunar orbit, and that required the vehicle to be firing its engines about 2/3 of the time. It takes only 3 days or so to get from low Earth orbit to low lunar orbit if you use a high-thrust solution such as was done with the Apollo missions, and that requires the firing the engines for only ten minutes or so.

First off, to be very blunt, most of "free thinkers" are idiots. Peer review is an important part of both science and engineering. The kind of criticism that goes on at this site is mild compared to what happens amongst practicing scientists and engineers. The standard mantra for such a review is "check in your ego at the door". That way, when you come out of the room feeling six inches tall, you can check your ego back out. In retrospect, if your idea has any merit, the criticisms will help you make forward progress. It is best however not to go into a peer review with a meritless, "free-thinking" idea. That 12-year old boy: Here he is in 2007. His name is David Hahn. His story is a rather sad one. A 1998 Harper's Magazine story: http://web.archive.org/web/20001215100600/www.findarticles.com/cf_0/m1111/n1782_v297/21281407/print.jhtml "The Radioactive Boy Scout" from the "Tales of the Nuclear Age" blog: http://talesfromthenuclearage.wordpress.com/2009/12/13/the-radioactive-boy-scout/

Bzzzt. Wrong. A thing that is not falsifiable is not a scientific theory.

Do you know what those adjectives mean? Incommensurable means unable to be compared (with what?) Since you did not say what your theory is incommensurable with, I can only assume that you mean it is incommensurable with everything: Existing theories, reality, ... If that is the case, why would I even be interested in reading it? Why would anyone? Irreducible means unable to be reduced. And you know this because?? Catholic presumably means universal here. Aren't you being redundant when you say this is a theory of everything? Unfalsifiable means it cannot be shown to be false, which in turn means you do not have a theory. Empirically validated means you have tested it. Against what? You just said your theory is unfalsifiable. With what? Do you have your own personal particle collider? Validated means someone has checked your work. Who? Did you submit it for peer review, or did you validate it yourself (never a good idea). Testable. But wait! You said your theory was unfalsifiable. Complete has a couple of different mathematical meanings, neither of which apply where. I am completely baffled with regard to your meaning. Consistent. Sorry, you can't prove this. Godel's theorems are going to get in the way.

OK, thanks for that. And yes, the location sucks. When the underlying software thinks I have last visited seems quite random. Sometimes it will thinks I last visited 8 minutes ago, other times, two days ago. The appearance is that it just pulls a number out of the hat. Does it really? I got completely random results when I tried to search for 41,000. The old search tool had lots of options. I could make it search only in selected subfora, look only for posts by a particular user, have it report results either as posts or as threads. I can't even find an advanced search tool with this new scheme. Another complaint: The underlying formatter is both too smart and too stupid at the same time. Heck, it is worse than Microstuff's Word, which is saying a mouthful. It is very easy to get mixed fonts when cutting and pasting. It is very easy to get stuck in a list. Where is the Make plain text button?

I'll try to be nice: The search tools in this new setup are awful. (Whew, no curse words. Told ya' I'd try to be nice.) The "View New Content" button has a rather random view of what is new. How do I find the posts made in the last day? The last two days? How do I find posts made by a particular user? Going to the user's profile and clicking "posts" shows the full text of the last two or three posts made by the user. Want to search for content? Doing a search forums gives random nonsense. Doing a google search on "<content> site://scienceforums.net" is much more likely to find what you are searching for. Edit: I now see that you have the merge working But it doesn't show a separator between the merged posts. Another issue: Touch a post, even 5 seconds after you post it, and you get "This post has been edited by ..." displayed at the bottom of the post. Any way to make that only show up if there is some reasonable lag between the initial post and the edit?

The entry page can take a long time to load.

Speed. The new scienceforums.net is slow.

jryan, you're still thrashing. Suppose the jobs have an immense amount of value. Execs #2, #3, and #4 may well go along with anything that exec #1 proposes because they foresee that should they vote against his proposal they will suffer the same fate as will exec #1. In other words, exec #1 can propose a split in which all of the money goes to exec #1; nobody else gets a dime. On the plus side, everyone gets to keep their fantastic jobs. We don't know what the value of the jobs are. All we can say is that the problem is underspecified -- or we can ignore the salary aspect and treat this as a mathematical rather than humanistic problem. (In which case you get to the Nash equilibrium solution.)

No, there isn't. You are making up information about salaries and such precisely because the problem lacks specificity. The only solution that makes any sense given the (limited and incomplete) information at hand is a 999997,0,1,0,1,0,1 split. The even numbered execs get nothing, execs numbers 3, 5, and 7 get a pittance, and exec #1 gets almost everything.

jryan, you are thrashing here. You are just throwing out solutions with no logic behind then. This is not the way to solve these kinds of problems. First off, interesting find. I suspect the OP changed the problem from pirates to executives so we wouldn't be able to find a solution on the 'net. Do note that the author came to the same conclusion that I came to: This is an evens versus odds proposition. The following paragraph in that paper is key (epmphasis mine): The secret to analyzing all such games of strategy is to work backward from the end. At the end, you know which decisions are good and which are bad. Having established that, you can transfer that knowledge to the next-to-last decision and so on. Working from the beginning, in the order in which the decisions are actually taken, doesn’t get you very far. The reason is that strategic decisions are all about “What will the next person do if I do this?” so the decisions that follow yours are important. The ones that come before yours aren’t, because you can’t do anything about them anyway. This pirate problem is almost exactly the same problem as the topic of this thread, only it is a bit better specified. The reason that the pirate problem is a bit better stated is that there is no particular advantage accrued by moving up a notch on the fierceness totem pole. This problem is about executives, not pirates. In most companies, a huge financial advantage accrues from moving up the executive seniority totem pole. That isn't true in all companies. Some are much more egalitarian. (Prototypical example: Ben & Jerry's, at least up until 2000 when Ben and Jerry sold out.) Compensation is fairly flat in such companies; what is accrued in advancing up the totem pole is a bit more glory at the expense of a lot more headaches. The division in this kind of company would be simple: Even shares for all, with everyone patting each other on the back for a job well done. No mention of wheelin' and dealin' (the thing that salescritters do for a living). Imagine a more cutthroat corporation than a Ben & Jerry's. Exec #4 pulls aside execs #5, #6, and #7. "We can sink every proposal up to mine. I'll split the pot between us, and we can all move three notches up the ladder. BTW, hit men are cheap; don't think of voting down my proposal." This wheelin' and dealin' makes for a solution that is not a Nash equilibrium. The simplistic Nash equilibrium solution is simple: Exec #1 offers $1 each to execs #3, #5, and #7. The remaining $999,997 dollars goes to exec #1. This simplistic split is not realistic. Even ignoring the dollar value inherent in moving up the executive ladder, one of those three odd numbered executives may reject exec #1's proposal on grounds of fairness. So they lose a buck; exec #1's proposal is not fair. We humans (and other animals) appear to have some kind of built-in fairness mechanism. Google "Ultimatum game" for more.

Look at it from a bottom-up perspective, jryan. Posts #3, #4, and #10. Without any other info from the OP, this is clearly an evens-versus-odds proposition. Merged post follows: Consecutive posts mergedTo illustrate how much harder this is when the odd numbered execs get their shot versus the evens, consider that exec #1 needs 3 cohorts, #2 only needs 2, etc. In tabular form, [math]\begin{array}{ccc} \text{Turn \#} & \text{\# cohorts} & \text{As percent} \\ 1 & 3 & 43 \\ 2 & 2 & 33 \\ 3 & 2 & 40 \\ 4 & 1 & 25 \\ 5 & 1 & 30 \\ 6 & 0 & \phantom{0}0 \end{array}[/math] There is no turn #7. The last exec will never get a shot. Exec #6 gets the requisite 50% from his/her own vote.

Nice job. That the spit does not have to be even is, I think, crucial. Since the OP did not provide any information regarding the value of each position the question is essentially unanswerable. The OP also did not answer my question regarding wheelin' and dealin', and that can obviously change the outcome immensely. Of course, one way to overcome this is to not offer an even split. That #1 gets to keep his job might well be worth a lot more than 1/4 million. Heck, it might be worth so much that exec #1 will sweeten the pot with some of his own money. He could offer $1 million each to execs #3, 5, and 7, for example. I would expect that jumping up a notch in the hierarchy is worth more to exec #3 than it would be to exec #7. For most people, pay levels out as one progresses. Pay raises can be quite phenomenal for fresh-outs. Some fresh-outs simply aren't qualified to do fresh-out level work, and the pay for them reflects that. Once fresh-outs have proven their worth their pay jumps by quite a bit (percentage wise). After that, pay raises start becoming rather pathetic; eventually they barely keep pace with inflation. This is not the case in the cutthroat executive world. Pay starts going off the charts the higher one climbs. Exec #1 is most likely paid more, a whole lot more, than #2, #2 is paid a lot more than #3. Things probably start to flatten out from there. To forestall a rebellion by any one of his odd numbered cohorts, exec #1 may want to offer more to #3 than #5, and more to #5 than #7. As said earlier, the OP didn't supply enough information needed to truly solve the problem. All we can do is speculate. Merged post follows: Consecutive posts merged You are forgetting that by rejecting #1's proposal exec #2 gets a shot. Exec #2 only needs two cohorts -- and those two cohorts most likely will not include exec #5. Exec #5 stands to get zero by rejecting #1's proposal. Without any other info, this is an even numbered versus odd numbered execs proposition, and the evens have a distinct advantage each step of the way. Exec #1 needs three cohorts but exec #2 only needs two. Exec #3 needs two cohorts but exec #4 only needs one. Exec #5 needs one cohort but exec #6 does need any.

Read post #7, jryan. Why would exec #2 vote for your proposal? If he joins execs #4, #5, and #6 and votes against exec #1's proposal, exec #2 can get the same amount of money as offered by exec #1 and he will get exec #1's job.

There is no reason the second most senior exec would accept such a deal. Suppose he rejects the deal along with those other three. The first deal is sunk, and so is the topmost exec. The new top exec only needs to find two cohorts to attain the requisite 50% vote. That's a bigger slice of the pie for our former #2 (new #1) exec -- and he's the new #1 exec.

Is wheelin' and dealin' allowed ("Vote against this next proposal; my turn is next and I'll reward you nicely")? Merged post follows: Consecutive posts mergedWithout wheelin' and dealin', the top person offers a four-way split amongst himself and execs #3, #5, and #7. Let's suppose it goes all the way down to #6. #6's proposal is easy: Everything goes to #6. #6 will vote for this proposal, garnering the needed 50%. Exec #7 will be screwed if it gets down to #6. Before it gets down to #6, #5's proposal needs to be sunk. Unlike #6, #5 needs 1 cohort to go along with his proposal. #7 will go along with anything #5 proposes so long as it is better than nothing. Exec #6 will be screwed if it gets down to #5. Before it gets down to #5, #4's proposal needs to be sunk. #4 also needs 1 cohort to garner 50%, the obvious target being #6. Execs #5 and #7 will be screwed by #4's proposal. Before it gets down to #4, #3's proposal needs to be sunk. #3 needs two cohorts, the two who would be screwed by #5's proposal. #3 offers a three-way split between himself, #5, and #7. Execs #4 and #6 will be screwed if it gets down to #3. Before it gets down to #3, #2's proposal needs to be sunk. #2 also needs two cohorts to get 50%, and these are execs #4 and #6. Execs #3, #5, and #7 will be screwed if it gets down to #2. Before it gets down to #2, #1's proposal needs to be sunk. #1 needs three cohorts: Execs #3, #5, and #7. Exec #1 should offer a four-way split amongst himself and execs #3, #5, and #7.

That's a good thing. You will not always have a calculator on hand to give you the answers, and if you do have a calculator, you will not know if the answer is correct (you might have made a mistake pushing the buttons). We both speak English, and the basics are pretty much the same in any language. Math is math, afterall.

You are in college. There are lots of people there who use computers to do exactly what you are talking about. Rather than asking us what a good language to learn would be, ask them. Ask your advisor. Go snooping around in labs and ask the RAs what they are using. Find out who is publishing papers in this domain at your school and ask those authors. Don't ask us. All you will do is provoke religious wars and get a bunch of wrongheaded answers. Absolutely. Merged post follows: Consecutive posts merged That is an insult. I am more than willing to learn new concepts. I try to learn a new language every year or so. I can easily list twenty plus languages that I have learned over the last thirty years. I did not count several completely immemorable whose names I can no longer remember. ... and sloppily, and more or less by yourself. You are in academia, and you are in a computer science department. Sloppiness and working in very small teams are almost a given. Some elements of computer science used to address issues of reliability, maintainability, understandability, verifiability, verifiability, traceability, cost, and above all, developing and sustaining a large set of knowledgeable workers. Some computer science departments still do concern themselves with such issues. Many no longer do; those boring, real world concerns are now addressed by a rather new discipline, software engineering. The above gets at what the real issue is. It is a modern version of Snow's Two Cultures. Bascule and I are from two very, very different cultures. I worry about reliability and all that crap. Bascule worries slapping crap out quickly. Both concerns are crap, but hey, its the crap we have to worry about. I worry about competing with other companies. Bascule worries about competing with others in academia. These are very different kinds of pressure that lead to very different world views. Different cultures. I worry about being able to hire scientists and engineers who have a rather limited concept of computer programming, computer science, and software engineering. Bascule worries about the keeping up with the state of the art in computer science. Again, very different cultures. I was a part of the 1980-1987 AI revival. I learned several AI languages and made some inroads into applying AI to NASA (one of my programs helped keep a Shuttle flight flying after a major on-board failure). I was also taken in by the AI winter that followed that revival. One reason for that AI winter was that most scientists and engineers could not grok Lisp, rule-based reasoning, or, heaven forbid, backward chaining. The people coming out of schools who could understand logic programming could do Blocks World just fine but were for the most part completely incompetent when it came to real-world applications. There never was a sufficient mass of people who could bridge the different cultures and produce success stories. AI went into a massive decline because of a lack of success. Academic computer science and real-world science and engineering are very, very different cultures. Bascule comes from the former while I come from the latter.

Probably not. Bascule hates useful languages. He has been fully indoctrinated. A few questions to help you narrow things down, ecoli: What domain are you interested in? I do not mean stochastic modeling; that is far too broad. I mean something like atmospheric modeling, chemical modeling, biological systems, ... Academia or industry? Does one, maybe two, languages dominate in that field? If so, you know what you eventually need to learn. It would also behoove you to learn something of the art of computer programming. Scientists and engineers for the most part are quite lousy at programming because they have either learned it on their own or have learned it with the aid of other (equally inept) scientists and engineers.

Surely you jest. Those gross statistics include several programs that are at best peripheral to scientific computing. Haskell even beat C/C++ on a few of those, particular those that are heavy on threads. When you look at the benchmarks that are not peripheral to scientific computing you get a completely different picture. Take one that is near and dear to me: the n-body problem. C++ beats Haskell by nearly a factor of 3, Ruby by a factor of 58, Python by a factor of 73. To boot, this is using the very simple symplectic Euler integration scheme with spherical gravity models. If you look at the Haskell and Ruby and Pascal code, it looks gasp procedural. How much more procedural would the Haskell code look if you had to use a non-simplistic integration scheme and spherical harmonics to represent gravity? How much slower would they be compared to a language suited to scientific computing? Exactly, and you are not going to fight that culture. Scientists and engineers who never touch a line of code in their lives think procedurally. Scientists and engineers who program are first and foremost scientists and engineers. My employers over the past 30 years have uniformly found that it is generally a bad idea to hire computer scientists for anything by computer science type work because computer science majors, for the most part, are incapable of thinking like a physical scientist or engineer. It is a cultural thing.

Exactly. Scientists and engineers, at least the ones I work with, do not think functionally. They tend to think procedurally -- even the ones who have never touched a line of code. Speed is important because we do some very computationally intensive calculations. Just imagine watching the nightly news, where the weather forecaster says "Our new Ruby-based atmospheric model finally churned out an answer. We had a 50% chance of rain six months ago." Popularity is important because we have been using computers to solve problems for fifty years. We have a lot of existing solutions, some written a long, long time ago. Switching to a different language is an extremely expensive undertaking. Doing so is only justified when (a) the new language offers a *lot* of improvements and (b) it is almost impossible to hire skilled people with knowledge of the archaic language used in the legacy systems. Most of the FORTRAN code I encounter (e.g., atmospheric models) is anything but modern Fortran. There is a lot of FORTRAN IV code out there in the scientific world. Admit knowledge of FORTRAN (FORTRAN became Fortran with Fortran 90) and you might well be the stuckee in interfacing with (or horrors, maintaining) that incredibly poorly written FORTRAN code.

Modern computer languages SUCK when it comes to performance and when it comes to mathematical descriptions of physical processes such as the atmosphere. Trying to force scientists and engineers who model physical systems to think functionally is just wrong. That is not how they think. They think procedurally. FORTRAN was written for the scientific community and has evolved with continual oversight by the scientific community because it works well with the way they think. I personally do not like FORTRAN. However, in my opinion, it is better suited to how engineers and scientists, and particularly how atmospheric scientists think, than any "modern" language.

That's the same boat I'm in. "Modern" computer languages seem to have forgotten that some of us still use computers for computing. I've never used C# (we don't do windows), and while Java is nice, it makes Matlab look fast. My experience: Implement the same algorithm in Fortran, C, C++, Matlab, Java, and Python. Fortran and C are about the same, with Fortran just a tad faster. C++, if you are careful, and if you cache a lot of things as pointers, can be almost as fast as C (but making that happen makes the code darned ugly). Without paying attention to speed, I find C++ to be about half as fast as C. Matlab and Java are, in my experience, well over an order of magnitude slower than C, and can be much, much worse. Python is just pathetic. An order of magnitude or more increase in computation time means that the overnight ten thousand case Monte Carlo simulation would take a week or more to accomplish, or (more likely) that pathetically weak arguments would have to be given for reducing the number of cases to a few hundred. The week-long machine learning analysis I once did, spread over a boatload of machines to boot: Forget it. Efficiency is usually the last thing I worry about in scientific computing. That nasty slowdown caused by using C++ in lieu of C or Fortran can usually be mitigated by hacking at a small portion of a very small number of computationally-expensive algorithms. I'll take C++ over C any day. There is no hacking around an order of magnitude or more slowdown.

I learned Lisp twenty+ years ago. It changed my life, literally. That I knew Lisp, could teach others how to use it properly, and could apply it to solve some rather complex problems were motivating factors in my then-employer moving me to my current locale. (That I brought Symbolic's Lisp machine #2 with me as my dowry didn't hurt ...) Lisp teaches you to think differently, and better. The best thing to do is to learn a bunch of very different languages. I do not particularly like Python (I loathe Python), even though you can do neat things with it ... My bias is a bit personal. A coworker has attuned me to accessibility issues. I have a few Python modules that I just modified to add open/close braces as stupid comments because the Python developers reject requests to adopt braces as "overmydeadbody". I'd dump those Python modules for a more sane language if I possibly could do so. I absolutely loathe the whitespace indentation in Python. It's one of those coffee stains on the tray tables issues for me.

Some satellites rotate en masse -- the entire satellite is essentially gyroscope. These spin-stabilized satellites need to use some mechanism to counter the nutation and precession that results from spinning. Some satellites have internal gyroscopes for attitude control in the form of reaction wheels or control moment gyros. These are akin to the "gyros in a suitcase" used to drive hotel valets insane.