timo

The point where energy is put into the system is when water is moved from the ocean and moved up on the mountain. As far as I know the energy for that ultimately comes from the sun's solar irradiation.

I guess that largely depends on your implicit assumptions you make when speaking about "path finding". One thing that immediately comes to my mind is reaction and protein folding paths in organic chemistry. You might think of finding a reaction path with a minimal energetic barrier as a path-finding issue, but in a possibly high-dimensional space with a complicated cost function (and in my case without actually knowing much about chemistry). Generally, I think one could fantasize about many different optimization problems being describable as path finding. The first limit to such fantasies will probably be the actual constraints/assumptions of your solution.

In that case ...:

It would be soooo awesome for lazy people like me if you could be bothered to still answer the question instead of just linking to a non-further explained text ("very good paper" is not an explanation) that does not even contain any of the terms "testable", "untestable" or "test" in its body. Would also somehow serve the "discussion" aspect of this forum.

I don't know what that is supposed to mean, and attempts of making sense of it failed at the stage where I suspect you put a lot of implicit assumptions into your reply. My best interpretation of "two independent variables and one equation for each variable" so far was assuming two first-order differential equations dX/dx = f(x,t) and dX/dt = g(x,t) (with X being the property in question). But my gut feeling is that already this starting point is not what you meant.

Two quick comments: Your original question has already been answered with "no", I believe. The 500 Watt listed for your power source is peak power. If it was average running power, then running your computer alone 24/7 would require more 500 W * 8400 h/y = 4200 kWh of electricity, which is above the total annual consumption of an average (German*) household. That would be a very significant source of electrical energy consumption, indeed! My desktop has a power rating of 60 W, btw. (*) Values can change significantly between countries. I took Germany as a reference because I happen to know the numbers. Countries with cheap electricity, many air conditioning systems or simply a solid ignorance for environmental affairs may have larger electrical energy footprints. To my knowledge it is commonly believed that a key enabler for fully-renewable energy supply scenarios is improved energy efficiency on the demand side. That often refers to thermal efficiency of buildings. But electric efficiency of appliances does not seem to far away from that.

May be a chicken-egg thing. In my experience, it is not that you start out with a wave-like solution and then want to express it as a 2nd order differential equation. But that you arrange conditions on your system, come out with a 2nd order differential equation of a particular kind, and know that the solutions to this are wave-like.

The statement "the electromagnetic force is stronger than gravitation" is popular, but at least not necessarily correct. It is correct for atoms, but incorrect for the earth-moon system where electromagnetic force is so insignificantly small that it is completely neglected. To answer your question: Consider two electrically charged masses at a distance d. Write down the expressions for the gravitational force |F|=G m1 m2 / d² (with m1 and m2 being the masses and G being the gravitational constant) and the force for the electrostatic force |F| = E q1 q2 / d² (with q1 and q2 being the charges and E being some constant that I currently don't know what it equates to - just look it up). You can then compare these values for different combinations of m1, m2. q1, q2 and d. A more detail analysis will also reveal that the distance d in this case is insignificant for the question which force is greater. Hope that helps.

Non-terrorist muslims are probably not supposed to count as real muslims in the context of this discussion . Asking if Islam can be watered down under the premise that watered-down Koran readings do not count as Islam seems a bit mood to me. But apparently it still has enough volume for three pages of conversation.

As a side-comment: Teaching has traditionally been considered one of the "higher" forms of a field in Germany. For teaching in university until recently you needed a "habilitation", a special scientific certification usually obtained during the end of the process of becoming a full professors (*). Emmy Noether was not allowed to do a habilitation and hence not allowed to teach. The lectures she gave were officially lectures of David Hilbert, with everyone looking away from the fact that Prof. Hilbert wasn't physically present in his own lectures. (*) Remark: recently, becoming a full professor does not require a habilitation anymore, but that would go too far to discuss in detail. EDIT: I bothered reading her WP article after writing the above. Apparently Mrs. Noether later was allowed to do her habilitation and to teach. Still, I find the story about her initially giving lectures inofficially (because everyone knowing her knew how good she was) quite interesting.

I don't know how many muslims you know. I know quite a few, some of them actually being religious (most are about as religious as the average european christian, which is not very much by US or fundamentalist standards). I not only coexist with them peacefully, some of them I actually call friends. And that's with being one of those atheist infidels. None of them declared a holy war recently, as far as I know.

A hype term I recently hear very often in relation to databases are graph databases (https://en.wikipedia.org/wiki/Graph_database), a particular case of the already-mentioned NoSQL databases (which are a similar hype term). A somewhat well-known incarnation of this is Neo4J. Depending on other details of your project you may also consider if there are standard database-like solutions relating to the technology stack you already use or plan to use. For example, for one of our Java projects one consultant recommended using JPA (https://en.wikipedia.org/wiki/Java_Persistence_API) - we did go for a custom-made solution, though. For relational databases my gut feeling mixed with some limited experience tells me MySQL should be fine. EDIT: Please assume that when writing the above I was not aware of the contraint "web" in your thread title. You'll have to check to what extend solutions proposed match this criterion.

I don't think your "Environmentalists" seriously want civilization to go back to a stage before early agriculture. Even if some people behave as if that was the actual intention of polar bear lovers.

Unless he OP usually uses a different programming language than you usually do. Out of curiousity: In which programming languages does no initializing a basic float value end up with an error or null?

I am not sure what your objection is, or even if this actually is supposed to be an objection to the link. Do you believe the IPCC report fails to explain "what leads the 97% of scientists to believe that man is the biggest contributor"? I cannot tell, but I expected the report to be a good, rough, 1000-page long overview, assuming hololeap does not want to go into all details. Or are there not enough pictures of polar bears? [*] I do not know exactly what hololeap is looking for - and the thought occurred that hololeap is not actually looking for information at all but rather trying to make a point. But I think a webpage complaining about global warming sceptics getting an over-proportionate amount of media coverage or covering studies indicating that republicans might be convinced of global warming with proper education may be a bit too meta. [*] Yes, I will mention the term "polar bear" in every post in this thread. I'll even post a picture as a measure of last resort

You could try this little tousand-page handbook: http://www.ipcc.ch/publications_and_data/publications_ipcc_fourth_assessment_report_wg1_report_the_physical_science_basis.htm . It's a report of many of those 97% of scientists in which I believe they try to explain what leads them to their concensus. Should lie somewhere between the white papers and the polar bears that impressed you so much. But I must admit I did not completely read it before proposing the link

Given that you are still in your first year an obvious path seems to be to switch to physics. But note that being a physicist I read "interested in pure physics" as a small red flag. It indicates that you are interested in a vision of physics without knowing what it really is about - at least I do not know what "pure physics" would be. Your incorrect statement about high-energy physics being purely theoretical also goes into this direction: not sure if your grammar was unprecise or if your vision is wrong - high-energy physics is so experimentally-heavy that their experiments like LHC are well-known even to people outside of physics, whereas few people outside the field could name any biophysics experiment. But both cases may be indicators better not to go into physics, especially not theoretical physics. And naming MIT first is also a bit suspicious; I find it awkward that so many people mention the world's most famous engineering school as their destination of choice for a degree in natural sciences. One would hope that the content comes before the fame of the university. I am aware these comments are a bit personal. No offense meant by that, and you are of course free to ignore them as the non-sense of some stranger on the Internet. But I would have felt bad not mentioning that the overall feel of your post is that your plan is not really though through at this point (which is not a bad thing, you should merely be aware of it). EDIT: Might have not posted this if I had seen that the thread is over a month old. But it's written now so I leave it here.

I do not know either. But reading your post I get a few ideas. Generally, negative reputations tends to be given out sparsely on SFN in my experience (with maybe a bit increase lately, but that may be stochastic noise). It tends to be given for things like "this was really offensive", "troll post" and "quit ignoring anything that was said in the discussion and reposting the same claims all over again". In short, for bad behavior. Not as a shortcut for saying "you are wrong, but I cannot be bothered to correct you". I am not completely sure what "mods don't let me post negs" means exactly. But I do appreciate that the moderators here tend to support the discussion aspect of the forum and take measures to not let this forum turn into a point-and-click battleground.

It easy to show that gravity does not always pull to the center of mass of an object. Consider a test mass at location (0,0,0) and a pulling object consisting of essentially two equally-massive large masses located at (1,0,0) and (-3, 0, 0), respectively. A calculation will reveal that the gravitational pull is in positive x-direction, i.e. away from the center of mass at (-1, 0, 0) which lies in negative x-direction.

Neither does the existence of a non-zero energy at T=0 imply that T=0 could not be reached, nor is that claimed in the Wikipedia pages you linked. What the two links claim is that thermodynamics assumes T=0 cannot be reached by thermodynamic processes (link 1) and that at T=0 the kinetic energy is not zero (link 2).

I do not think the Microsoft Windows Calculator is really targeted at theoretical computer scientists. Hands-on computer scientists will, at least in everyday work, have to be aware of the convention their programming language gives them, anyways. In my experience that is usually log referring to the natural logarithm.

Go ahead and convince the math and physics community. It's not that we do not know of the notation "ln". It's merely considered archaic by many.

It is a common misconception to assume that inventions must be neccessarily attributed to a single person or a well-defined small group of people. That is only required for the newspapers to write an article about the invention (basic rule of journalism: put a face on your story). And maybe for companies who need to justify putting a patent on buttons on the computer screen. EDIT: But maybe I should also try to anwer the question from my very limited historical knowledge: As far as I know modern (natural) science started with the guy around the time of Newton, where mere philosophising about how things could work was being backed-up with systematic quantitative experimenting. In reality it was probably a much more gradual process than my limited understanding of history suggests, though. And one thing one should also keep in mind is that western society probably does not sufficiently take into account the development in other parts of the world.

Your understanding that "any force must equate to some kind of energy" is probably wrong. Problem 1: Force and energy do not even have the same physical dimensions/units.

That depends on the field, as already said. In physics and math, for example, it usually denotes the natural logarithm (in my experience, at least). Also see https://en.wikipedia.org/wiki/Logarithm#Particular_bases . @fiveworlds: The planethmath convention may be to specify it. But I do not think that is common practice in a professional environment. Unless one explicitly means a non-standard base, of course (non-natural logarithm in my case as a natural scientist). In many cases the base should be clear from the wider context, anyways.