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Both are bad left wing propaganda pieces. I don't want to play that game other than to comment on this gem from the article referenced above: Oh please. The exact same thing can be asked about the Democrats lack of support for any one of the many balanced budget approaches the Republicans have offered. The answer is simple: The proposals made by the Democrats were intentionally laced with arsenic, as were the proposals made by the Republicans. Neither party wants a real solution. Both instead want to score political points by making the other party look bad. And that is the heart of the problem. Right now, compromise is a four letter word to both Democrats and Republicans. Maybe after November this current recipe for disaster will change. I sincerely hope that the result of the November elections is an even closer House and Senate than we have now, and a squeaker for the Presidency. No mandate for either party, please. I want a mandate for solving the dang problems instead. My biggest fears are that the elections will result in a clean sweep (Presidency, Senate, and House) for one party or the other. I don't know which clean sweep would be worse. Right now now it looks like the Senate could easily flip to Republican due to the large number of Democratic seats up for re-election, the House could easily flip to Democrat due to the large number of Tea Party Republican wins in 2010. The Presidency? It will come down to hanging chad yet again.

As a follow-on, here's the derivation of that ‘Equation of Trickery’. The first equation in the paper is the first equation in section I.3 of Einstein's 1905 paper, [math] \frac 1 2 \biggl[\tau\Bigl(0,0,0,t\Bigr) + \tau\Bigl(0,0,0,t+\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\biggr] = \tau\Bigl(x',0,0,t+\frac{x'}{c-v}\Bigr) [/math] This is just [imath]1/2(\tau_0+\tau_2) = \tau_1[/imath] (light always travels at c), with [imath]\tau[/imath] expressed as a function of x',y,z, and t. Now do a first order Taylor expansion of [imath]\tau[/imath] about (0,0,0,t). The left hand side becomes [math] \begin{aligned} \frac 1 2 \biggl[\tau\Bigl(0,0,0,t\Bigr) + \tau\Bigl(0,0,0,t+\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\biggr] &= \frac 1 2 \biggl[\tau\Bigl(0,0,0,t\Bigr) + \tau\Bigl(0,0,0,t\Bigr) + \Bigl(\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\frac{\partial \tau}{\partial t} + \mathcal O(x'^2)\biggr] \\ &= \tau\Bigl(0,0,0,t\Bigr) + \frac 1 2 \Bigl(\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\frac{\partial \tau}{\partial t} + \mathcal O(x'^2) \end{aligned} [/math] The right hand side becomes [math] \tau\Bigl(x',0,0,t+\frac{x'}{c-v}\Bigr) = \tau\Bigl(0,0,0,t\Bigr) + x'\frac{\partial \tau}{\partial x'} + \frac{x'}{c-v}\frac{\partial \tau}{\partial t} +\mathcal O(x'^2) [/math] Equating left and right hand sides, [math] \tau\Bigl(0,0,0,t\Bigr) + \frac 1 2 \Bigl(\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\frac{\partial \tau}{\partial t} = \tau\Bigl(0,0,0,t\Bigr) + x'\frac{\partial \tau}{\partial x'}+ \frac{x'}{c-v}\frac{\partial \tau}{\partial t} + \mathcal O(x'^2) [/math] The [imath]\tau\Bigl(0,0,0,t\Bigr)[/imath] terms on the two sides cancel, and in the limit [imath]x'\to0[/imath], the higher order terms vanish. What's left is [math] \frac 1 2 \Bigl(\frac{x'}{c-v} + \frac{x'}{c+v}\Bigr)\frac{\partial \tau}{\partial t} = x'\frac{\partial \tau}{\partial x'}+ \frac{x'}{c-v}\frac{\partial \tau}{\partial t} [/math] Factoring out the common factor of x' yields [math] \frac 1 2 \Bigl(\frac{1}{c-v} + \frac{1}{c+v}\Bigr)\frac{\partial \tau}{\partial t} = \frac{\partial \tau}{\partial x'}+ \frac{1}{c-v}\frac{\partial \tau}{\partial t} [/math] This is the equation that the author of the paper entitled the ‘Equation of Trickery’.

Article 1 is a straw man misinterpretation of the principle of relativity. From the abstract, The other postulate of ‘laws by which physical systems undergo change are not affected when referred to different inertial reference frames’ is in contradiction with all the derivations in the article. Since the change in any physical system; due to whatever reason; could be mainly in reference to the space and time of that physical system; whereas article derives that space and time of any physical system would be different when referred to different inertial reference frames. Einstein's postulate says that the laws of physics are the same in all inertial frames. It does not say that space and time are the same in all inertial frames. Another problem in this first paper is that the author assumes that space and time are absolute and then uses this assumption to prove that space and time are absolute. Article 2 is also at vixra: http://vixra.org/pdf/1202.0004v1.pdf From that paper, None of the physicists, till date, seem to have bothered as to from where Einstein had got the ‘Equation of Trickery’. That ‘Equation of Trickery’ follows directly from the first cited equation in the limit of infinitesimally small x'. It's quite simple. There is no trickery other than perhaps the use of partial derivatives and the standard physicist semi-abuse of infinitesimals. Yes, partial derivatives are tricky. Yes, physicists abuse infinitesimals all the time. Nonetheless, it works. Non-standard analysis shows why we physicists have been able to get away with this for so long. Note that there are more rigorous derivations of the Lorentz transformation from Einstein's postulates that avoid the use of infinitesimals. They're longer, and they don't add anything other than being more rigorous. There isn't anything fundamentally wrong with Einstein's formulation.

It's the other way around. We've occasionally had some economic upswings that have masked these growing problems. The underlying problems have been there all along. Two big problems are hordes of lost jobs and a baby boom that is starting to retire. Some of those lost jobs result from jobs moving to other countries, others due to increased efficiency, and yet others because whole industries have vanished. Neither punishments nor rewards will bring those jobs back. Those jobs are gone. We need to create new industries, new markets that will employ lots of people and do so acknowledging that different people have different skills. (Not everyone can learn to be a rocket scientist.) Nobody has a clue regarding how to accomplish this. Regarding the baby boom, this has been a problem politicians have known about for decades. They didn't do anything about it decades ago because it wasn't their problem. It's our problem, and it's here to stay.

Nicely said. This is especially the case when the gauntlet is tossed in some crackpot journal. This recent onslaught of crackpot / extremely low quality journals is problematic, and the technical publication industry certainly is not helping with their rather extreme price gouging.

Sorry, you're wrong. Relativity is one of the most strongly tested theories in all of physics. Just because you don't understand it or because it doesn't fit with your worldview doesn't mean that it is wrong.

For "someone to take over the reigns", we, the voters, would have to give complete control to one party or the other. We, the voters, have been quite reluctant to do that. For good reasons. Each party sees an obvious solution to the budget morass: Simply cut all that worthless junk from the budget and change the tax code in a fair manner and in such a way that more revenues come in. There's a problem with this. Republicans and Democrats don't quite see eye to eye. They disagree strongly on what constitutes worthless junk, and they also disagree strongly on how to change the tax code. The only way out of this morass is for the two parties to come to consensus on what to cut ("I'll agree to cut this program that means a lot to my side if you agree to cut that program that means a lot to your side") , how much to raise taxes, and so on. That's not going to happen until November, and probably not even then. The current problems will have to escalate even further to force the parties to lose their intransigence. "Compromise" will remain a four letter word until November.

Absolutely not! There is no difference between F=ma and F=dp/dt for constant mass systems. There's a huge difference for variable mass systems, and those who work with variable mass systems almost invariably prefer F=ma over F=dp/dt. Use F=dp/dt and force is no longer invariant. It's instead a frame-dependent quantity.

Wood preservatives?

Kinky! Edited to add: I think you meant some word other than preservatives. See http://en.wikipedia.org/wiki/Preservative.

Neither of these sentences make sense. Try again, but not in this thread. Invoking Newtonian mechanics is not valid when relativistic effects come into play. The mass of a photon is zero. The momentum is not zero. End of story. Note well: Discussions regarding the mass of a photon do not belong in this thread. This thread was split from the photon mass thread because the issue raised in apurvmj's post was off-topic to that thread. Similarly, discussions regarding the mass of a photon are off-topic to this thread.

Nah. It would make it a theorem of everything. Law is just another term for theory, maybe even less than that. In any case, all of this is tangential to the topic of this thread. Even if there was a "theory of everything" that explained all four fundamental interactions, it still wouldn't be applicable to describing (for example) predator-prey relationships. Different sciences attack rather different problems. There is no one size fits all in the sciences. If anything, it's the other way around. Sciences are getting more and more specialized as time passes. Saying that one science pwns all the others is just silly.

That recent work is from the Eöt-Wash Group, which I previously referenced in post #8. I initially thought to cite that 56 micron figure in that post, but as you noted, even that is a bit fuzzy. I instead decided to be intentionally vague with the phrase "sub-millimeter range".

No, it doesn't. It means that two teenagers in Europe can have sex with one another without too many repercussions. Shocking as this may sound, teenagers in the US are having sex with one another, too. One part of the difference between age of consent laws in continental Europe versus the US is that the US is a bit puritanical in its views on sex. Unmarried people aren't supposed to have sex. Age of consent laws in the US essentially establish an age limit for marriage. Another factor is the difference between civil law (continental Europe) and common law (Britain and its former colonies). Judges have a lot more leeway in civil law nations than the do in common law nations -- if the law doesn't get in the way, that is. So laws in civil law nations are often written so they won't get in the way. Having sex with a twelve year old is obviously wrong. The law is hard and fast here. Having sex with a 14 year old? That depends on the circumstances. Two horny teenagers will get a slap on the hand and be told to use birth control. Your forty year old man having sex with a 14 year old can easily be tossed into a nasty Spanish prison.

Your question is related to whether light has momentum, which it does. The standard view is that photons are massless -- that the intrinsic mass of a photon is identically zero. It's also good to keep in mind that Discovery Channel has fallen to the sad state of presenting woo as true.

Answering "10 microns" to the original post is a bit strong. That 10 micron figure is from Geraci et al., Improved constraints on non-Newtonian forces at 10 microns, Phys. Rev. D 78:2 (2008). What Geraci et al. were looking to rule out at very small distances were large forces, 104 to 108 times the gravitational force between the test masses. A picture (source: http://physicsworld.com/cws/article/news/2008/mar/05/gravity-test-constrains-new-forces) tells a thousand words: In the above image, the horizontal axis is length and the vertical axis, α, is the magnitude of a non-inverse square force, with α=1 representing a force equal to the gravitational force between the test masses. The shaded part of the graph represents areas where a non-inverse square reaction has been excluded. Different experiments focus on different portions of the distance/force region in that plot. The Stanford group focused on large forces. The University of Washington group has focused on forces comparable to gravity, so length is inherently a bit larger. Expanding that graph to an even broader scale results in this figure (Adelberger, E.G., Heckel, B.R., and Nelson, A.E., “Tests of the gravitational inverse-square law”, Annu. Rev. Nucl. Sci., 53 (2003), http://arXiv.org/abs/hep-ph/0307284):

This is not quite right. Liquid water cannot exist in equilibrium at pressures below the triple pressure, ~612 Pa. That's about seven orders of magnitude higher than the pressure in interplanetary space (~10-4 Pa, or less). Talking about what happens to liquid water in vacuum is asking about non-equilibrium physics. For example, what would happen if a glass container holding liquid water was sent to outer space and then shattered? The water would boil -- at least at the boundary. The boiling would be very explosive. The vapor would not form into snow. However, the explosive nature of the boiling would create droplets that would in turn explosively boil into micro-droplets, and some of these micro-droplets might turn into snow. The reason is that the act of boiling steals heat from the remaining water due to heat of evaporation. Heat of evaporation would also make some remnant of the original quantity of water freeze. End result: A lot of individual water molecules, many small particles of ice (which sublimate rather quickly), and several larger blocks ice (which will sublimate over astronomical timeframes). Too me this is a much more interesting question. Astronaut Don Pettit (also a PhD chemical engineer) has done a number of "Saturday Morning Science" experiments with liquids in space. You can see several of them at this site: http://physicscentral.com/explore/sots/. One of them, "Episode 2: Bistro-nauts", obliquely discusses fuel tanks. How do fuel tanks work in zero G? This is a big problem! There are basically two solutions. One is to put a bladder in the tank. The fuel is on one side of the bladder, a pressurized gas on the other. As fuel is removed, the gas expands and forces the bladder to keep the fuel intact. The other is bladder-less tanks, which use surfaces with weird, sharply angled shapes to move the fluid toward the port thanks to surface tension. Google the term "propellant management device" for more info.

Yes, they have. People misread "not solvable in the elementary functions" as "not solvable". That is wrong.

I too am quite encouraged by these developments. One thing to keep in mind is that the vast majority will inevitably fail. After all, the vast majority of restaurant startups fail, and starting a new restaurant ain't exactly rocket science. Starting a new private space exploration venture? That is rocket science. There's almost always a typo even after you proofread. Well, at least for me there is. I liked the prior software which didn't report that I had edited my post if I caught the problem and fixed it in short order (5 finites, IIRC).

A theory of everything would cover both general relativity and quantum mechanics. Biologists don't use Newtonian mechanics, relativity theory, or quantum mechanics to describe predator-prey relationships, and they would be even less likely to use this theory of everything. The same goes for sociologists and their descriptions of group dynamics. Different sciences operate at different levels of abstraction. The very detailed level at which physicists work is inappropriate for most aspects of the life sciences and is completely inappropriate for the soft sciences. We physicists tend to look down on the soft sciences as being less scientific, but then again, those in the softer sciences tend to look down on physics as being unimportant to humanity. IMO, both of those viewpoints are wrong.

I was discounting Mars One as non credible. All of the credible Mars terraforming projects require a nuclear reactor. What happens to those light thin-film solar panels when the first Martian storm hits? Six landers, more than six launches from Earth, all for six billion dollars? That is not credible. Baloney. They use tons of new technology. Powered landing of those large landers on Mars. We don't know how to do that. Growing food on Mars. We don't know how to do that. Rovers that can haul large landers around on Mars. We don't know how to do that. Precision landing on Mars, in close enough proximity for those rovers to move the landers to one spot. We don't know how to do that. Extracting water and oxygen from the Martian soil. We don't know how to do that. Aside: What water ice in the Martian soil? There's water ice in the Martian soil near the poles. Away from the poles, not much. Note that depending on power from solar arrays is highly problematic near the poles. They are extracting water and oxygen from the Martian soil. That's mining and refining. Just because a technology exists on paper does not mean that it is an existing technology. Just because an existing technology has been used in a very different setting does it mean that it will work when used in a radically different environment. An existing technology deployed in a radically different setting is a new technology. NASA has learned this lesson, so have the various incarnations of the Soviet Union / Russian space programs. There's no discussion of the landing process at that site. There's very little discussion of growing food. There's very little discussion of power, and no discussion of how the facilities will be powered at night. There's no discussion of waste management. There's no discussion of how to handle medical emergencies. This is just bunk.

There is no link to his work. This was a competition for high school age kids. There is no publication of his results. There is an image: http://m.static.newsvine.com/servista/imagesizer?file=boyle6DB47079-0C04-F6B6-85A6-C21F964A3A06.jpg&width=600 <Aside: What is this BS: I am "not allowed to use that image extension on this board"? Oh well. You can click the link.> This is a known result. It's also not that useful. It's for velocity rather than position, and it's implicit rather than explicit. He also offered a solution for position, but this was in terms of a series. Neither solution is not a closed form solution in the elementary functions. There are tons of problems that cannot be expressed as closed form solutions in the elementary functions. This is one of them. This particular problem, is not an unsolved mystery. The above image is from Alan Boyle's Cosmic Log, http://cosmiclog.msnbc.msn.com/_news/2012/05/28/11920006-16-year-olds-equations-set-off-buzz-over-325-year-old-physics-puzzler. Alan Boyle is one of the very few reporters who got this story correct. Wikipedia is another place that got this story correct. The wikipedia entry on Shouryya Ray has been deleted. Here's the discussion on the vote to delete: http://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletion/Shouryya_Ray, and here are a couple of blog articles by a wikipedia editor on this subject: http://thorehusfeldt.net/2012/05/29/shouryya-ray-and-the-press/ and http://thorehusfeldt.net/2012/06/05/shouryya-ray-closing-remarks/. Part of the problem stems from Shouryya Ray's initial misinterpreting "not solvable in the elementary functions" to mean "unsolvable". For example, [imath]\int_0^x \exp(-(t^2))\,dt[/imath] is not solvable in the elementary functions. That doesn't mean it's unsolvable, period. Big difference. A much bigger part of the problem stems from very bad reporting. Reporters for the most part are drooling idiots when it comes to science, math, and technology.

That, too. I was hoping that that search would have been kinda obvious.

Google is your friend. Why don't you do some of your own research first? A good start is with "small-scale test of gravity inverse square law".

It's in the sub-millimeter range. Gravitation is an extremely weak force, so looking for potential small-scale violations is rather difficult. There are multiple groups that do just this. Two of them: The Eöt-Wash Group at the University of Washington and the Birmingham Gravitation Group at the University of Birmingham.