Cap'n Refsmmat

What exactly does it hit? Objects? "The universe"? Air? How does light propagate through a vacuum?

Light does exert force on objects it strikes; that's called radiation pressure, and is why solar sails work. Furthermore, that force is indeed dependent on color -- specifically, the force depends on the light's momentum, which in turn depends on its energy, which is a function of wavelength. This would of course make blue light more powerful than red light, rather than the other way around. However, light does not have mass. As for Dekan's explanation: no, that does not make sense. With the Sun at horizon-level, if one color were heavier than another, we'd see a smeared-out rainbow-like image of the sun. The red Sun would appear low, since the red light is dragged down; the blue portion of the sun's light would appear higher, making the Sun look like a poorly-printed newspaper whose colors don't quite line up. Sunsets are already adequately explained by Rayleigh scattering.

Different angles are different reference frames, in this analogy. You've only examined Earth from one. This should be very clear from my earlier "jest." Why do you think we should choose the "objective earth", in Earth's reference frame, when Earth is hurtling at high speeds through the universe compared to many other astronomical objects? You're just choosing an Earth-centric point of view. You still haven't answered how subjective idealism can work when the viewpoint from different reference frames is deterministic. The atmosphere doesn't "get" thinner; it is thinner in their reference frame. You can view the problem in two ways: as a matter of lifespan, or a matter of length contraction. It merely depends on the reference frame you choose. I will be out of town until Tuesday.

Nope. Earth science is right... in this reference frame. Any observations Earth scientists make in this reference frame do not prove anything about how Earth appears to someone in a different reference frame. Your argument is like saying "I've stared at this side of the statue for four hundred years, so you can't possibly be correct about what's on the other side, which I have not yet looked at!" Lorentz contraction of spaces 200 miles wide is known to exist, given the muon experiments mentioned earlier -- the muons enter the atmosphere many miles up, and reach the ground. They find that that significant distance is contracted. You're the one denying the substantial evidence for all parts of relativity.

That's because it doesn't. Regardless, that doesn't contradict my point; they do correlate exactly, in that I can transform observations between reference frames and get exactly the correct answer. That's hardly subjective, is it? Any bans on SFN are made with the agreement of multiple staff members. Nobody is banned for being wrong or against the mainstream; they are, however, warned for presenting incorrect or unproven ideas as the answer to a discussion in the mainstream science sections of the site.

How can relativity be considered subjective idealism if "reality" as seen from any reference frame is inextricably mathematically related to the "reality" observed in another reference frame, independent of the perceptions and thoughts of the observers that exist in that frame? Subjective idealism would seem to suggest that observations in any reference frame could just be anything, since reality is but a perception of our mind. But no, we find that our observations correlate in a much deeper way. Also, I'm offended by the insinuation that I am petty enough to ban someone for a slightly snide remark. We do not punish people for making mildly derogatory remarks about things they do not fully understand.

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Earth science has thoroughly established Earth as nearly spherical in our reference frame. A physicist can tell you exactly what it will look like in any other reference frame. I suppose one could make an analogy to looking at a sculpture. If I stand at one angle and view a sculpture, I see a certain view; if someone else stands on the other side, they see something markedly different. However, if I have knowledge of the shape of the sculpture, I can tell you how it will look from any angle, and the varied appearances do not mean that the reality of the sculpture is entirely in my mind.

Well, it is. But I can take the squished Earth and use the relative velocity between Earth and observer to calculate what an observer sitting on Earth would see, and I would calculate that he'd see something very nearly spherical.

The key point against relativity being a form of subjective idealism is that observations in any reference frame can be transformed into observations from another frame using a predictable and consistent mathematical formula. I can determine exactly what should be observed in any reference frame if I know what I observe in mine. That's hardly subjective.

Yes, I'd forgotten about that for a moment, but I'm assuming the scientists on their rocket ship are decently competent physicists. The relativistic Doppler effect would certainly make Earth look rather strange as well. A couple months ago I started an online relativity simulator with another SFN member. I should get back to working on that. It could be useful for discussions like this.

There's no inertial frame of reference for which the Earth is a flat surface. No velocity will achieve that, just like no reference frame includes a circular, flat Earth on the backs of four elephants which walk on top of a giant space turtle. Don't be silly. They're not flying at c, they're stationary. It's just that the Earth is moving particularly fast in their general direction. They're stationary, so it's their measurements that make sense, not ours. How could you propose we rely on measurements taken on Earth when Earth is moving so fast? If we consider the space of velocities and directions I may travel in, very few possibilities have a spherical Earth. The majority of situations, if you chose randomly, would have an observer traveling at a significant fraction of light speed compared to Earth. Face it: you're outnumbered by hypothetical observers.

What do you mean? They had plenty of time to make observations, perform experiments, use radar and laser measurement technology, and pull every trick in the book. The Earth is definitely a flattened oblate spheroid. I don't know why you think that centuries of knowledge are relevant; we had centuries of knowledge of miasmas and bad airs causing tuberculosis, and we all know how that worked out.

I dunno; the Earth scientists I asked as they shot past on their rocket were very definite about the Earth being a remarkably oblate spheroid. Apparently it looks like it's been squished in one direction. I can't imagine how you could think the Earth is nearly spherical; it's a tough, rigid body, so stretching it out to a sphere would be impossible. You just can't do that with solid rock.

The lab I worked in a year ago had a chart on the wall listing chemicals and the gloves that may be used with them; we used acetone all the time to clean equipment while wearing nitrile gloves, but IIRC the chart said that was a bad idea. I still have hands, though.

Yeah, there are tons of good code editors for Windows these days. Notepad++ is the one I've heard most about. You might also consider Komodo Edit, jEdit, or any of the other big names.

Do you use Dreamweaver as a WYSIWYG editor for HTML, or just as a code editor?

The receiver's clock can be corrected using time signals from multiple satellites: http://en.wikipedia.org/wiki/GPS#Correcting_a_GPS_receiver.27s_clock

Again, this is why we must clarify our points very carefully. CharonY's graph shows definitively that as a fraction of GDP, total state, local, and federal taxes have not increased since the 50s. The article I pointed to from USA Today shows that as a fraction of household income, the federal, state, and local combined tax burden is at the lowest level since 1958. But if you want to argue that total tax revenues are higher than ever, sure... Also, increased spending doesn't have to happen with increased revenues, as I'm sure the deficit crisis has made you aware. This also demonstrates how politics threads often get derailed by minor points because posters don't clearly express their points and cite dodgy evidence (like quoting revenue and GDP statistics rather than tax burden). Unfortunately it's nearly impossible to enforce rules about this.

That's what I get for trying to remember what I read in a popular science book. I suppose it's one of those metaphors which makes everything very much clearer while being wrong in nearly every detail. Thanks for the explanation.

I doubt it. Considering the economic pickle the EU is currently in, the US's fierce independence, and the stark differences between the political atmosphere in the States and in Europe, I doubt we'd get along very well.

Do you have prior programming experience? If you don't like the thought of spending hours typing code, you may not enjoy computer science; there's certainly a lot of mathematics and theoretical courses, but there will also be programming projects. Lots of them. Lots of courses on data structures to be used by programs and algorithms for solving problems when programming. It sounds like your interests would work well with physics. If you like being hands-on with interesting concepts, you won't be disappointed by physics, although your first few years in the degree will of course be old, settled physics, not new and exciting stuff.

One must also consider income growth. Higher government revenue is unimportant if family incomes have shot up dramatically, as is in fact the case. The current tax burden, as measured as percentage of family income and including federal, state and local taxes, is at the lowest point since 1958. http://www.usatoday.com/money/perfi/taxes/2011-05-05-tax-cut-record-low_n.htm

Seems to me that adding deliberate misspellings to your code is a great way to slow down people trying to crack it.