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Why? That begs the question that an anomaly even exists. What does exist are limits to the applicability of 14C dating techniques. Several of the test results touted by creationists were definitive experiments to assess those limitations. There is no arguing with young earth creationists. They are immune to logic and evidence.

An astronaut in orbit still has weight if you use the tautological definition of weight being mass times gravitational force. How many times do I have to say this: There are multiple, conflicting meanings of "weight". You are stuck on just one.

Read the previous posts, Lance. That is not the definition of weight used in advanced physics classes (weight is mass times accelerometer reading) and even in some intermediate physics classes (weight is what a spring scale measures). Gravity isn't a real force. It's a pseudo force. Pseudo forces (centrifugal force, coriolis force, inertial force) have two things in common. One is that the magnitude of such a force acting on an object is proportional to the mass of the object. Gravity: The gravitational force acting on object is proportional to the mass of the object. The second thing pseudo forces have in common is that the pseudo force acting on some object cannot be measured by any sensor on that object. Pseudo forces are not intrinsic forces. They instead are a consequence of the observer. Gravity: There is no way to measure the gravitational force acting on an object. This is a direct consequence of the equivalence principle. Correct. Also correct. Also correct. However, that deceleration results from some real force acting on the object. The scale is measuring those other forces. It is not measuring the gravitational force. The gravitational force is unmeasurable. From a Newtonian perspective, the reason is that the gravitational force cannot be shielded. From a general relativistic perspective, the reason is even simpler: Gravity is not a real force. The rest of your post indicates your thinking is too Newtonian. While gravity is a real force in Newtonian mechanics, it is not a real force in general relativity. Newtonian mechanics is not the be-all and end-all to physics. In physics, the model that more accurately represents reality is the winner. General relativity does a better job of explaining reality than does Newtonian mechanics. Gravity is not a real force.

The premise doesn't conform with reality. That mass causes gravitation is a well-observed phenomenon. The planets orbit the Sun, satellites orbit their planets. This is an observed fact. You have proposed something that flies in the face of reality. The behavior of objects due to mass is very well explained by extant theories. A new theory of gravity will have to simplify to these existing theories because these existing theories are very well-confirmed within some range of applicability. For example, Newton's law of gravity simplifies to the constant acceleration of 1 g observed by Galileo and others under conditions of close proximity to the surface of the Earth and simplifies to Kepler's laws under conditions of a bunch of small objects (e.g. planets) orbiting a very large object (e.g., the Sun). General relativity simplifies to Newtonian gravity under conditions of small mass concentrations, moderate distances, and small velocities. A future theory of gravity will similarly have to simplify to yield general relativity in the domains where general relativity has been observed to be correct. Physicists have three concepts of mass. Active gravitational mass, passive gravitational mass, and inertial mass. That different masses generate different gravitational fields is again a well-observed phenomenon. Active gravitational mass is a measure of the strength of the gravitational field generated by some object. Given a gravitational field generated by some massive object, the passive gravitational mass of another object represents the interaction between the object and that gravitational field. Finally, there are other forces of nature. The inertial mass of an object dictates how objects react to those non-gravitational forces. The equivalence principle hypothesizes that these three distinct definitions of mass are equivalent. The equivalence principle is one of the best observed phenomenon of all of physics. Where exactly your conjecture fails is a bit hard to pin down. The reason: There's not much to it. You have not supplied a mathematical description. All you have supplied is meaningless philosophical rambling.

This is not a theory. It is a WAG (wild-assed guess), and a bad one at that. The first thing a scientific theory must do is conform to reality. This doesn't.

We can't feel gravity. Suppose you are standing upright with your arms hanging at your sides. You can feel forces other than gravity, including the upward normal force of the ground on your feet (which keeps you from sinking into the ground) and the upward tensile force of your shoulders on your arms (which keeps your arms from falling off). Thought experiment: Imagine a tunnel (walls made of unobtanium) that goes all the way from the surface to the center of the Earth, evacuated of all air. This serves to separate the concepts of pressure and gravity. Now imagine taking an elevator that slowly descends to the center of the Earth. The Earth's gravitational force will drop off roughly linearly with depth as one descends, becoming zero at the center of the Earth. Now suppose you take pressure readings through the unobtanium walls as you descend. The pressure will rise because the material is (nearly) in hydrostatic equilibrium. The downward force of the weight of the material above is balanced by an upward force of the compression of the material below.

It's not an illusion. It is very real. You are assuming weight is mass times gravitational acceleration. This is not the only definition of weight used by physicists (see my prior posts), and IMHO it is not a very useful one. Why not? Simple. No device can be constructed to measure weight defined this way. Weight in general relativity is mass times the reading from an ideal accelerometer. This is a useful definition because it suggests a measurement scheme. With this definition, an astronaut in orbit is weightless.

There are scientific dictionaries, mooey. This one specializes in chemical and environmental terminology. This one specializes in biological and paleontological terminology. This one is a metadictionary of links to several jargony dictionaries. There are even jargon to jerga translators (and probably jargon to жаргон translators, as well). For example, this one is a bilingual English-Spanish dictionary that specializes in dental terminology. And this one defines physics jargon. It of course leaves common words like exist to the common dictionaries.

Those people are correct. Your argument that weight is a force carries less weight than theirs that it is mass. Legally and colloquially, weight is mass. Our scientific definitions of weight are jargon. The people who write dictionaries always view jargon as having less weight than the common use of a word. The gravitational force and normal force acting on an astronaut nearly cancel when the astronaut is standing on the surface of the Earth. When the astronaut is in orbit, the normal force is essentially zero. So are you saying an astronaut is weightless when he is on the ground, but not when he is on orbit? If not, you need to rethink what you just said.

"Centripetal" means "toward the center". Another name for centripetal force is central force. Gravitation is a central force, and it certainly does not cancel itself. I suspect you might mean centrifugal force, and that of course is not a real force. It is instead a fictional force. For all practical purposes, the only real force (Newtonian mechanics) acting on Mercury is that of gravitation. Other forces include drag against the interplanetary medium and the solar wind and solar radiation pressure; these are tiny. Those other forces don't come close to canceling that of gravity. The term "weight" has several conflicting meanings. Legally, weight is a synonym for mass. To a lawyer and to a merchant, the contents of a can of vegetables weighs exactly the same on the Earth, on the Moon, and on the International Space Station. Forgetting the legal definition (who cares?), the term "weight" has multiple meanings even within the context of physics. One definition of weight is simply mass times the acceleration due to gravity. In this sense, Mercury is anything but weightless. Then again, an astronaut in the space station is anything but weightless by this definition. Their weight is about 90% that of what they weigh on the surface of the Earth. So why do we say astronauts are "weightless" when they are in orbit? Simple: Their weight as measured by a spring scale would be near zero. A spring scale doesn't sense gravity. This leads to the second definition of weight: the net force acting on an object except for gravitational forces. For a person standing on the surface of the Earth, these two definitions of force are nearly identical in magnitude and nearly opposite in direction. For a person in the space station, the two definitions are quite different. A third definition of weight is mass times the acceleration measured by a perfect accelerometer. This is essentially the same as weight as measured by a spring scale. The reason a scale or an accelerometer do not and cannot sense gravity is deep. Scales cannot sense fictitious forces such as centrifugal force. Gravity itself is a fictitious force in general relativity. In Newtonian mechanics, gravitation is a real force. You will do fine looking at gravity as a real force until you start studying general relativity. If you are a 12th year student, that won't happen for three of four years. I'll stick with the Newtonian interpretation for the rest of this post. What do you mean by this? In particular, what is a "perfect orbit"? You appear to have a misconception of Newton's third law. Not surprising; most pre-university physics instructors themselves have a poor understanding of Newton's third law and they impart this misunderstanding on their students. An example of a misapplication of Newton's third law: A person standing on a spring scale. Many instructors teach that the downward gravitational force by the Earth on the person and the upward force by the scale on the person is an example of Newton's third law. This is completely wrong. A third law pair always involves the same force acting on two different bodies. The cited example is wrong because it involves two different forces acting on one body. Moreover, the forces are not equal but opposite. The person is undergoing uniform circular motion at the rate of one revolution per day. There are several third law force pairs involved when considering a person standing on a scale. The Earth exerts a gravitational force on the person. The third law counterpart: The person exerts an equal-but-opposite gravitational force on the Earth. So what about the scale? That is the normal force (electrostatic repulsion). The scale is exerting an upward force on the person. This upward force keeps the person from sinking into the scale. The third law counterpart: The person exerts an equal-but-opposite normal force on the scale. This in turn compresses the scale's spring. The reading displayed on the scale is this compression, translated from distance to force by means of Hooke's law.

I'll take a look, but later this afternoon/evening. I'll even look out for a goth version. x[/hr] I've poked around some. I didn't see anything that grabbed me. Most have too many adornments, goofy fonts, goofy color schemes: Too much pizazz with too little thought regarding readability and understandability. OTOH, genecks might like this or this.

You are not understanding what I wrote. You claimed that it is the centripetal force that stops Mercury from falling into the Sun. That statement taken by itself is incorrect, for two reasons. First, any centripetal acceleration (a kinematic rather than dynamics concept) will not do. The centripetal acceleration has to take the correct form. Orbits are not stable if, for example, the centripetal acceleration is of the form constant+f®. Things get even more restrictive when moving from kinematics (centripetal accelerations) to dynamics (central forces). While circular orbits are metastable for any central forces of the form krn, they are stable only if n>-3. Moreover, closed orbits only appear if f=kr (e.g. Hooke's law) or if f=k/r2 (e.g. gravitation). Secondly, the object in question needs a non-zero angular momentum with respect to the central body. An object with zero tangential velocity relative to the Sun will fall into the Sun.

That's not quite right. Here is a thought experiment that shows a counterexample. Put a pulley wheel on a pivot so the pulley wheel can rotate around the pivot. Attach a string to a mass and string the string through the pulley. Now swing the string so the mass undergoes circular motion. Now start pulling the string through the pulley. The rock will hit the pulley when the string gets short enough. Note that at all times the force on the rock is a central force. The reason Mercury does not fall into the Sun is because (a) Mercury has a non-zero angular momentum with respect to the Sun, (b) ignoring relativistic effects, gravity is an inverse square central force, and © perturbations such as those due to relativity and other planets are small. That is only true for a circular orbit. Mercury does not have a circular orbit; it's not even close (eccentricity=0.206). No. The magnitude of the acceleration is related to the distance only. That is how gravity works.

Looks good. Note: Using the dot product rather than the cross product will yield a simpler expression. TBH, it appears you might be relying on Maple a bit too much. Try to solve like these by hand first.

While this can turn into a fun discussion, it ain't physics. Moved to the "General discussion" section.

Put your cuboid with the vertex in question at the origin and with the edges leading away from this vertex aligned with the x, y, and z axes. Express the diagonals in question as vectors. What simple vector operations (there are two; pick either one) say something about the angle between the two vectors?

Many superheros are apparently endowed with variable inertia (or maybe the writers are endowed with super stupidity?) This was written in 1970 or so. Story concluded at http://www.larryniven.org/stories/Man_of_Steel_Woman_of_Kleenex.shtml.

Write the problem as a vector equation.

Blue is a bit of an eyestrain to me. I have some blue daze (pictured above) planted next to my mailbox that can be painful to look at on a bright sunny day. I like the cork background on this site. Whatever you do, please do not go to this skin. What were they thinking?

I wasn't calling you an idiot, I was asking you what you meant by "It needs something with black." Since the forum does have "something with black" (the text), that is obviously not what you are asking for. You are asking for more skins, in particular, a gothic skin. That may or may not be reasonable request; Cap'n Refsmmat is the one who can answer that question. (Depends in part on how much tweaking he has to do to the skins.) Those aren't just my views. They are the results of several studies. Some well-written blogs on this topic: http://www.456bereastreet.com/archive/200608/light_text_on_dark_background_vs_readability/ and http://www.joedolson.com/articles/2006/08/on-the-readability-of-inverted-color-schemes/. I really like the background (cork?) on the first of the two web site cited just above. That said, some human factors studies on readability are <choice word deleted>. For example, Readability Of Websites With Various Foreground / Background Color Combinations, Font Types And Word Styles, which found that italicized green Times New Roman on a yellow background offers the best readability. Riiight. Please no. xxx[/hr] Off-topic: New word! Unfortunately, I couldn't find a definition in any online dictionary or in my big fat old-fashioned unabridged dictionary at home. I did find enthymeme (an argument containing a hidden premise) and enthymematic (in the form of an enthymeme). From use in context (here, here, here), it appears "enthymatic" means "enthymematic". In which case, isn't "enthymatic understanding" a bit of an oxymoron?

The text is black, the background is light blue -- in the forums proper, that is. What exactly are you asking for? Does what you are asking for make sense from a human factors POV (readability, comprehensibility, "easy on the eyes")? Light-colored text on a black background is hard to read for people with astigmatism (half the population; it gives them headaches). A lot of websites are incredibly hard to read because the page designers don't know a thing about human factors. This forum is for the most part fairly easy on the eyes. Some places where it isn't: The blue text-on-blue background of the search results is a bit hard to read (too little contrast). Identifying the Administrators with red letters against the dark blue background of the banner literally hurts the eyes (avoiding red on blue at all costs is very basic human factors stuff).

Read up on Reed Smoot. He faced an expulsion hearing for being someone they didn't like. The Senate did come to his senses and voted not to expel him.

Megadeath from an excess of naval gazing?

From the Wiki article, "The Court's interpretation was that the clause meant that expulsion was the only method for a House to determine the qualification(s) of its members." In other words, Reid will have to gather 2/3 of the Senate to vote to impeach Burris. Can he do that?

My eyes glazed right over that "midnight GMT". To be even more pedantic than swansont, GMT is an obsolete concept. Time as measured by an atomic clock has been the standard for some time now: TAI (International Atomic Time; the acronym is apparently backwards because the acronym is properly in French). Swansont mentioned also mentioned UT1 and UTC. UTC is what is broadcast on the US radio station WWVB (and others) and via internet as Network Time Protocol (NTP). UTC is simply TAI plus or minus an integral number of seconds, the cumulative number of leap seconds. UT1 is an after-the-fact determined version of time tied to the Earth's rotation. Those aforementioned leap seconds keep UT1-UTC between -0.9 seconds and +0.9 seconds. Pedantic? Yes. Important? Depends on who you talk to. Mind-numbing? Ask the guy (PhD in astronomy) on our team I assigned to be our expert on time. He still hates me for that assignment (not really). His exact words: "A pedantic pile of <expletive> replete with pre-scientific nomenclature plus angels-dancing-on-a-pin arguments about which time frame is best suited for dynamics."