D H
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Everything posted by D H
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Self pity is not a good thing. Something quite remarkable happens to people as they learn ever more: They learn how little they know. It is the unskilled and incompetent who don't know that they are completely unqualified to comment upon something. Perhaps you should read this: J.Kruger and D. Dunning, Unskilled and unaware of it: How difficulties in recognizing one's own incompetence lead to inflated self-assessments, Journal of Personality and Social Psychology (1999) 77:6 1121-1134. http://people.psych.cornell.edu/~dunning/publications/pdf/unskilledandunaware.pdf
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You aren't familiar with the Michelson Morley experiment and yet you feel qualified to conjecture on physics? Your conjectures are pure, unadulterated nonsense. That's not surprising as you aren't even familiar with the most basic facts. I just do not get this phenomenon of people who feel qualified to conjecture on some subject of which they are completely ignorant, and completely ignorant by their own admission!
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Of course not, for the same reason we haven't brought back unicorn horns from Hyboria, or wherever it is that those elusive unicorns live.
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"That web page"?? Seriously? That web page happens to be either the #1 or #2 science journal in the world. Not just anyone can publish there.
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You did, you just joined a science forum that allows crackpots to have their say. For a while. It keeps us on our toes, and we do learn something when someone truly knowledgeable slaps the silly posters upside the head. Your posts were appreciated. Some of us did learn something from them. Thanks!
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NASA finds planet outside of our solar system eerily similar to Earth
D H replied to The Peon's topic in Science News
There are no theoretical space craft able to reach astonishing speeds. The only space craft able to reach astonishing speeds are found in science fiction. The one possible exception in the Alcubierre drive. However, many experts in general relativity find the physics of this to be dubious. Even taking it as valid, the energy required to move even a few atoms is more than the entire energy output of the Sun. So, a non-starter. While money can buy lots of things, one thing that it can't buy is a way to violate the laws of physics. -
Try 400 million years. http://www.nature.com/nature/journal/v271/n5643/abs/271316a0.html. Your conjecture is nonsense.
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I saw this speech as pretty much a run of the mill final state of the union address by an incumbent President running for reelection with a Congress that is either divided or belongs to the other party. Presidents of both parties tend to hold back on what they think is the true state of the union until the final speech of their second term. The final speech of their first term is inevitably a campaign speech. This was very much an anti-Mitt Romney kind of speech. Several of Obama's statements were direct barbs at Romney, with not much said against Gingrich or Paul. Obama and his reelection committee would love nothing better than to face Gingrich or Paul. Either one of those two as an opponent would result in very close to a clean sweep for Obama. The campaign will be a lot tougher and the election a lot closer should Romney win the Republican nod.
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There's plenty of evidence, arguably better than fossil evidence. The title of this thread, "The failure of fossil records", is a bit disingenuous. Perhaps I'm being over sensitive, but that is a phrase straight out of the creationist playbook. Creationists argue (underhandedly, IMO) that anything but a complete record is an abject failure. Biologists from Darwin see it as remarkable that the fossil record can tell us anything. A complete record, as others have already pointed out, is not needed to tell us quite a bit about how things were and what lived a long, long time ago. To answer the question raised in this post, ice cores from the Antarctic, Greenland, and mountain glaciers all over the world tell us a lot, an awful lot, about the climate of the recent past, recent meaning the last million years or so. The seasonal changes mean that those ice cores are banded, year by year, just like tree rings. They are time machines that let us look year by year into the ancient past. The variations in thickness, variations in amounts of soot and other aerosols, variations in chemical makeup, and variations in isotopes tell us quite a bit about snowfall, volcanic activity, average temperature, continental erosion, biological load, etc. Those ice cores are a treasure trove.
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With no background in physics, don't you think that a better plan of action for you just might be to learn some physics rather than to make up nonsense? How are we to collect this bucket of nonsense? And it is nonsense. Learn some physics. The Feynman lecture series is an excellent way to start.
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Baloney. More baloney. And even more baloney. Just because you said this is the case does not mean it is true. You are making a bald assertion here; please read the rules of this forum. There is absolutely no scientific evidence in favor of an expanding earth. None, zero, zip, nada. There is overwhelming scientific evidence that subduction has occurred and continues to occur. There is overwhelming scientific evidence that the Earth is more or less the same mass, and more or less the same size that it was shortly after its formation. There is overwhelming scientific evidence that the physical constants have indeed been constant over the last 4.5 billion years (the age of the Earth).
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THe OP is anything but specific. Keep in mind that this poster apparently believes in the ultra-crackpot nonsense of the expanding earth "theory": http://www.scienceforums.net/topic/63469-expanding-earth-theory-missing-mass-resolved.
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You might want to rethink that. I went into that particular interview to see if I wanted to work for that company. My employer at that time was on the verge of being bought out by a larger company. We were told not to pass this information along to anyone. I obeyed that mandate. However, nobody told me that I couldn't go on a job interview with that potential buyer. I needed to see if I was going to stick around should the deal go through. Fortunately, being a small part of a big company, the group with whom I interviewed didn't know that their corporate masters were about to engulf and devour my corporate masters. I didn't really care if I did or did not get the offer. I wanted the offer as an ego boost, but getting the offer was not the main reason I was interviewing. (I eventually did get the offer, but I did not accept it.) Besides asking canned questions, this interviewer made another huge gaffe: He talked money first. I pretty much got the answer I wanted when he gave a figure that was 80% of my salary at that time.
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I once answered with something along the lines of: Being short and snippy when asked stupid questions such as what is my greatest weakness. I did get the offer.
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Of course there are. Oceanic crust is considerably denser than continental crust. The continental crust float, the oceanic crust sinks. It's simple physics. You appear to be on the verge of creating a fallacious argument. If that is truly your intent, please read the rules you agreed to abide by when you joined the site. If on the other hand you are just a bit confused about modern geology, ask away. You are assuming here that "there are no rules", that "each plate is apparently able to do what it wants, slip, slide under, slide over, go up, down, left, right." That's just wrong. The motion is not (completely) random. There are "rules". You are ignoring that oceanic crust is (a) much denser and (b) much, much younger than continental crust. The two go hand in hand. Subduction is oceanic crust sliding underneath continental crust. The opposite process, continental crust sliding beneath oceanic crust, occurs but rarely because of the huge disparity in density. This subduction pulls oceans apart but also pulls the continent across the ocean toward the subducting ocean crust. Well of course not. You are assuming there are no rules, that the process is purely random. This is falsified by your own statement. It's not random. There are "rules."
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Same here (I interview quite a few people). I almost never ask that stupid interview question, "What is your greatest weakness?" I try to ask questions for which the interviewee does not have a canned answer.
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What philosophy is that? Perhaps composition fallacy, perhaps false dichotomy, perhaps begging the question, perhaps all three at once? You are ignoring that a relativistic observer can calculate what a stationary observer would see. You are defining the "true shape" of the Earth to be that shape seen by a stationary (or non-relativistic) observer and then saying that relativity is wrong because a relativistic observer doesn't see that shape. That's a fallacy, not logic. Every argument you have made in this thread is just one fallacy after another.
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How can you raise something to the power of i?
D H replied to questionposter's topic in Speculations
Where does one exist in reality? Not one planet, one apple, one meter. Just one. How about pi? The square root of two? Math is an incredibly power tool that we use to describe reality. That does not mean that it is reality. Saying that it is is confusing the map for the territory. -
T.V. ? You mean that silly box where you see crap about Nostradamus and ancient aliens? Let's start with a non-rotating, uniformly dense spherical Earth. Drill a negligibly small tunnel that passes through the Earth. It's a fairly standard freshman physics problem to show that a test mass falling through this tunnel is a simple harmonic oscillator that has exactly the same period as the orbital period of a test mass orbiting just above the surface of the Earth, or 84.3 minutes. Falling from the surface to the center of the Earth takes 1/4 of this period, or just over 21 minutes. The Earth is not a uniformly dense sphere. Density increases markedly with depth, with the most marked change at the core/mantle boundary. The simple uniform density model overestimates the required time. The correct answer is less than 21 minutes (it's about 19 minutes). I haven't the foggiest why someone would have said three hours. That is utter nonsense.
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Sure. Pluto and Charon, and closer to home, Earth and its Moon (were the Moon just a bit more massive it would have to be classified as a twin planet rather than a moon).
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Oh please. Stating a bald assertion in ALL CAPS does not make it true. It is still a bald assertion. You are the one making extraordinary claims. The burden falls entirely on you (not us!) to demonstrate with mathematics the validity of your claims and to suggest an experiment that will demonstrate the validity of your claims. You have done neither. Special relativity has absolutely no problem with the speed of light through your glass rod being the same regardless of orientation of the rod. In fact, special relativity says that the orientation of your rod has no observable effect. (Note: General relativity says otherwise, but the rod would have to be unrealistically long to make the effect observable.) You presume correctly.
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No, it doesn't. A constant acceleration means the local density is 2/3 the average density, where average density is the total mass inside the sphere out to the radial distance in question divided by the volume of that sphere. You'll end up with a nasty Volterra integral of the second kind. Never mind. You're correct. A constant acceleration from the core to the surface would require [math]\rho® = \frac 2 3 \bar{\rho}(r_0) \frac{r_0}{r}[/math], where [math]r_0[/math] is the radius of the core and [math]\bar{\rho}(r_0)[/math] is the average density of the core. Whether this is something that is at all generalizable seems rather dubious. Never extrapolate from a sample size of one.
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Given that, your supposition in post #11, "If this were true, we could measure e.g. the speed of rotation of the Earth, by measuring differences in velocity of light in a glass rod (flint 170 000 km / s) in the parallel direction to the Earth's movement and in the transverse direction to this movement.", is incorrect. You are the one making extraordinary claims. The burden of proof lies upon you to justify your claims. Stationary with respect to what? It's important to keep the historical context of the Michelson-Morley experiment in mind. The purpose was to find the medium via which electromagnetic phenomenon propagate through vacuum. Maxwell's equations indicated that electromagnetic radiation was a wave phenomenon that somehow propagated through vacuum. All wave phenomena known to physicists at that time required some medium through which the wave could propagate. So what was this medium that enabled light to move from the Sun, the planets, and the remote stars to the Earth? A stationary medium, one that moves with the Earth as it orbits the Sun, would make the Earth a very special place in the universe. It would also show up as some very weird (and never seen) variations in the light from the planets and the remote stars.
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How can you raise something to the power of i?
D H replied to questionposter's topic in Speculations
I'll go one step further: It is (per Rudin) the most important function in all of mathematics. With the exponential function it's easy (for positive real values of x): [math]x^{\sqrt 2}=\exp(\sqrt 2 \ln x)[/math]. This in fact is how a positive real rasied to a non-rational power is defined. It's called analytic continuation. You're going to have a very hard go at it if you want to describe [math]x^{\surd 2}[/math] without resorting to the exponential function. Without the exponential function, you are going to have to use a limit of a rational number that approaches the square root of two, Dedekind cuts, or Cauchy sequences. The only people who have to do that are math majors who have to show that the analytic continuation via the exponential and these alternative approaches are equivalent. No, it's just a misfortunate name. Mathematicians are, at there core, conservative and stodgy humanities majors who are loath to accept newfangled ideas. Just take a look at the names of some the kinds of numbers that mathematicians have invented. Irrational numbers. Irrational = not logical. The irrational numbers are numbers that don't make a lick of sense. The ancient Greeks threw Hippasus of Metapontum overboard for discovering the irrationals. That nomenclature sticks around to this day in the name "irrationals" and in the name for this symbol, [math]\surd[/math]. That is the "surd" symbol: Short for absurd. Negative numbers. Negative = not. The negative numbers are not numbers. Mathematicians did not kill the messenger this time around, but acceptance of the negative numbers as real took quite some time. Imaginary numbers. Once again, we have an unfortunate label that reflects on the reluctance of some mathematicians to accept radically new ideas. Giving the imaginary numbers a disparaging name helped ease that acceptance along. The term "imaginary" is just a label. Don't take it is meaning that complex numbers are any less "real" than the real numbers themselves. -
Yes, it is difficult to grasp because it is nonsense. Where is the observer, where is the rod, how long is the rod, what is the velocity of the rod with respect to the observer? How is the experiment to be performed? How are you measuring one-way speed of light in this rod?