Mr Skeptic

Like giving matches to children... Thanks! One of those is about information being destroyed or not in a black hole. Would it be possible to tell the difference between two black holes of equal mass, charge, and angular momentum, if, say one were made of matter and the other of antimatter? To that let me add, if you collided two black holes, one made of matter, and the other of exactly opposite antimatter, what would happen? Could you actually destroy a black hole like that?

I don't know how easy that is to do. Take some paint, and you can draw some pretty pictures, but you can't put the paint back in the jar. Stem cells have mechanisms to specialize into other cell types, but it might not work the other way. It might be easier to find a method to keep them from specializing than to find a way to turn them back. Only type that I know can turn back into stem cells are gametes, but that is where the controversy starts. Perhaps we could trick their precursors before they turn into sperm and eggs?

Most people here have suggested using hydrogen peroxide instead of water. It's a good suggestion, as H2O2 will easily break down to water and oxygen. But hydrogen peroxide is not as easy to find as water. I think that if you mix something with a higher electronegativity than oxygen with water, it will displace the oxygen to combine with the hydrogen. Mixing chlorine or fluorine gas with water will form HCl or HF and oxygen. These are exceptionally powerful gaseous acids and would probably kill you. I think you would want a solid that mixes with water to form an acid and oxygen. Disclaimer: I do not know very much chemistry.

Seems like a good idea. We've got to do something about coal, and not everyone has uranium. I'm not sure I understand why it is not considered a weapons risk. Thorium itself is not fissile, but Thorium 232 absorbs a neutron decaying twice into U233, which is fissile. Since Th and U are different elements, it would not be so hard to separate them. Is U233 not usable for weapons, or is it simply destroyed as quickly as it is created?

Is it science? Easy way to tell: can it make predictions about the physical world, such that if the predictions were wrong, the theory would be wrong? Also, could you put up a piece of your idea for the benefits of those who can't read rar files at the moment?

After considering what Klaynos and Martin have said, it does seem clear that I should change my starting point. However, I think I should change it to period or frequency, not time. It may seem like splitting hairs, but exactness is important in definitions. Besides, people might not know what time is, but they are very familiar with period -- the changes in time per event/cycle -- the ticks of a clock. And as Martin has pointed out, this is what we currently use to measure both time and distance. Atomic clocks are insanely accurate, so much so that they make light look slow So, here we go: wavelength [math]\lambda_{light} = \vec{c} T [/math] I wonder what would happen if I tried to replace distance with wavelengths... Period [math]T = \frac{1}{f} = \frac{h}{E_{photon}} = \frac{h}{\vec{p}c} = \frac{\lambda_{light}}{c}[/math] Period is a change in time per event or cycle. So now we can also start from knowing frequency, the energy of a photon, momentum of a photon, or the wavelength of light. Lots of stuff to think about.

There is ample evidence of such. Kittens in the wild do not have balls of yarn to practice their hunting skills with... Of course this is nature taking its course. Just another bunch of members of a species engaging in behaviour that increases both the individual's and the species' chances of survival. Only odd thing is that a few members of that species are knowingly opposing such behaviour. You made no distinction between human lives and animal lives before, why start now? Are you saying we are not part of nature? PS: one of the things that sets us apart from the animals is our more developed sense of morals, and the insane amount of power we have acquired due to our superior intellect, tool using ability, and language. Can you imagine just what would happen if a different species wielded the amount of power that we do?

Do you eat plants? Is not their life as important as yours? Do you take antibiotics when you are sick? What about the poor bacteria!?! I think that any human is more important than an amoeba, a fly, a frog, a mouse, a chimpanzee, or a plant. Don't you? Think carefully about all the resources you consume; they could be given to other living things. Even if you artificially created your own food from solar cells in outer space (so is to not impinge on the plants), that is food that could be given to some starving animal. Plants compete for sunlight, water, and nutrients; animals for food, water, and shelter. What one takes, is deprived from another. That's the nature of life. Competition and natural selection are not kind. Life is a competition, and we can compete pretty well.

Earnshaw's theorem assumes that only electrostatic interaction is holding things in place (and that they are not moving). This is not going to be the case, because you also have the ground holding the bottom magnet in place, which is not an electrostatic force. Rocket Man's suggestion to use a non-ferromagnetic hanging thing to prevent the magnet from flipping just might work. It would need to supply enough torque without being too heavy, and there would have to be the dip of magnetic field strength in the middle.

Uh, would it be ok if we replace your construction with a chain of length L and density 1 resting on a frictionless surface a distance d above the ground, with constant acceleration g? Then the gravitational force on the chain will be canceled by the normal force (the same force that prevents you from falling through the floor). That way we don't need to imagine an impossible gravitational field that is constant g and suddenly disappears. Anyhow, the problem you are having is that you assume both that the chain is in free fall (by your use of the equations for terminal velocity of an object in free fall), and that it is not in free fall (by stating that it moves off like a thread) If you know some calculus, I can cook up some equations for you. Otherwise, consider that only a portion of the chain has gravitational attraction, but it has to pull the mass of the entire chain. You can calculate the terminal velocity of the chain by using the law of conservation of energy: (1/2) m v^2 = m g h so v = square root (2 m g h /m) = square root (2 g h). This is why you should learn to love the law of conservation of energy; it will let you calculate things you wouldn't know how to do otherwise. Cheers, Mr Skeptic

Well, it all comes down to your values and priorities. Animal testing speeds up research and in doing so saves human lives and increases human comfort. But it kills animals and increases their suffering, by a lot more than it benefits humans. Call me racist, but I would rather animals suffer than humans. But whether I would agree or not on doing a particular experiment would depend on what animal is involved (eg fruit fly vs chimpanzee) and on how important the experiment is. You can't look at the world in such black and white terms. What I am more concerned about is the systematic elimination of habitats; while you are crying for a tortured lab rat, several species are going extinct. If I recall correctly, there was at least one regime that condoned experimentation on condemned prisoners. Not very popular. I do think that some convicts deserve a harsher punishment than a peaceful death, and bonus if they can give back to society, but the ability to profit from the death and suffering of others is likely to be abused. And there is likely an international ban on forced human testing since the Holocaust, and it would also be illegal with the current interpretation of the Constitution (in the US). In summary, I disagree with all your points. I'm a monster!

Thanks for the contribution It seems that we also need to understand what a cycle/event is (same with my use of wavelength, which would make no sense without a wave, to define momentum). Events are invariants in relativity, yes? I just realized that I changed my definition of energy to that of work and potential energy, but forgot about it. Also, that work definition should have been for change in work. Reason I changed it is because I had a bit of uncertatinty about energy. I think total energy (which includes relativistic) should be a sum of positive potential energy and positive total work energy, where the work might come from a different force than the potential energy. But trying to get positive potential energy has infinity problems, and it would also ASS-U-ME (useful mnemonic) that rest energy is potential energy. That seems like a reasonable enough assumption, given matter-antimatter annihilation, but I dunno if it still works if we have more matter than antimatter. More on that later, after I think a bit about it. Until it is fixed, all my definitions based on energy are suspect. You're probably right that this should go in general physics. the subject doesn't really fit in any particular area. And I think I pissed off some people in the theoretics section by using relatively simple (for them) math and then explaining it besides What are the requirements to make this a sticky? I'd still like to venture a little out of accepted definitions, like where I defined momentum in terms of wavelength rather than mass and velocity. Or should we condense it after we figure everything out? I still like the distance idea better, but due to popular demand, I had better start from time, or do both. I thought distance would be more intuitive, and preferred turning a vector into a scalar than a scalar into a vector. Since my first step is to define time and distance in terms of the other, it doesn't make a difference to past the second step anyhow. distance [math]\vec{r} = \vec{c} t[/math] Hmm, it does look simpler that way, but we need to know the direction the light is travelling, and knowing direction without knowing distance seems weird. Eventually, I will see if we can't define time/distance from various other starting points as well, and let people choose their favorite. [math]\lambda = \frac{h}{\vec{p}}[/math] etc. It seems to me that we are working with a system of n equations and n+1 unkowns. I think we are missing one more law of physics to tie all of these together (eg it seems to me that the period of an electron about an atom should be deriveable from basic principles). You are right about that: v = dr/dt was already defined; it is not my own definition, rather what (instantaneous) velocity means and has always meant. However, we didn't *know* what it was, because we did not know t. But we *know* that the speed of light is c (because we know light is an electromagnetic wave as defined by Maxwell's Equations), and we can use that to solve for t. Then we *know* both distance (which I said at the start you needed to know to know the rest) and time, so we now *know* velocity. In fact, most everything I wrote was already defined like that, with the exception of the few places I plugged a law of physics in instead, and the places I replaced some things with others.

We do see color differently. That's why we have adjustable red, green, and blue settings on our monitors. Some people's cones are optimized for a different color, so, say, the red wavelength the monitor uses might appear less bright.

Definitely. I don't know how to continue, but I was hoping that some people here who know more physics might be able to add something. I thought I got around that by using the speed of light. Since we know the speed of light, [math]\frac{d\vec{r}_{light}}{dt}=c[/math], then solving the differential equation to get t seems reasonable.

Well, the original "explained" series had some interesting if vague ideas, but the reaction to scrutiny was pure entertainment. The reason I did not choose time is because more people do not understand it (or is it that people know that they do not understand it?) . I might be able to derive everything else from a starting point other than distance and time, but it would look ... different. And more complicated. Perhaps that is reason enough to try it. The derivatives and integrals with respect to something other than distance and time might be impossible, though. I'm pretty sure that we want a distinction between rest mass and relativistic mass (or we could say rest energy and energy). Otherwise you would end up with massive photons or somesuch. Do photons have a gravitational field? Well, I thought that figuring out what all that stuff is was theoretical. And since explanation for momentum and everything past it uses the de Broglie wavelength and mass uses relativity, it is not very classical. That said, I don't mind if it gets moved elsewhere.

Here I attempt to show how if you understand what distance *really is* then you understand what everything *really is*, in nice, mathematically precise terms. Oh, and you also need to understand some calculus. The explanation for the title is that it is a salute to another poster who likes to tell us what stuff really is. Each definition is given in terms of previous definitions and physical laws, though I have occasionally added an alternative definition which doesn't, but serves more as clarification. Except, of course, for distance distance [math]\vec{r}= ? [/math] Well, I don't actually understand distance, unless we are talking about a flat space (which doesn't correspond to the real world). Mathematicians and folks who understand general relativity would know this, though. time [math]t=\frac{r_{light}}{c}=\int{\frac{1}{v}dr}[/math] Time is the distance light moves divided by its speed, which we know is c. You could also say that time is the ticks of a light clock. Or you could use the movement of something else if you really wanted to, but then you would have to know its speed. You already know the speed of light is c so you are better off using that. velocity [math]\vec{v}=\frac{d\vec{r}}{dt}[/math] Velocity is the rate of change of distance with respect to time; that is, how quickly something moves. acceleration [math]\vec{a}=\frac{d\vec{v}}{dt}=\frac{d^2\vec{r}}{dt^2}[/math] Acceleration is the rate of change of velocity with respect to time; that is, how quickly something changes its velocity. momentum [math]\vec{p}=\int\vec{F} dt[/math] or [math]\vec{p}=\frac{h}{\lambda}[/math] If you knew what force was, you could integrate it with respect to time to get the momentum (that is, momentum is the amount of time a force is applied). Or you could calculate it by using the wavelength of the particle (since you know distance). Then the direction of the wave (and hence, of the wavelength) would give you the direction of the momentum. Then momentum is a measure of how small your particle's waveform is. force [math]\vec{F}=\frac{d\vec{p}}{dt}[/math] Force is how quickly you change the momentum of a particle. work [math]W=\int_{\vec{r}_i}^{\vec{r}_f}\vec{F} \cdot d\vec{r}[/math] Work (energy) is how much force a particle has moved away from. I think that work should be a vector in the direction of the force, but no one seems to do that (and it seems to be taken care of by momentum, anyhow). potential energy [math]\Delta U=\int_{\vec{r}_f}^{\vec{r}_i}\vec{F} \cdot d\vec{r}[/math] (Change in) potential energy is how much force a particle has moved against. This is the opposite of work. The total potential energy is usually defined as being zero at infinity, so that it is always negative. This is a definition gimmick to avoid embarrassing infinity problems at [math]\vec{r}=0[/math] (which I take to mean that our usual concept of inverse square laws don't work at tiny distances). power [math]P=\frac{d\vec{W}}{dt}=\int\vec{F} \cdot d\vec{v}[/math] Power is how quickly you can do work. (relativistic) mass [math]m = \frac{E}{c^2} [/math] Mass is condensed energy. Dunno what kind of energy, just that it is energy. Or, it is the stuff that causes gravitation. rest mass [math]m_0 = \sqrt{\frac{E^2}{c^4} - \frac{p^2}{c^2}}[/math] Derived from Einstein's other most famous equation. Uh, I think you should only use the positive root, though. charge [math]e = \sqrt{\frac{F_{electric}r^2}{k}}[/math] Charge is the stuff that causes electrostatic attraction. (And yes, that is lame) So what do people think of this? I don't understand the strong and weak forces nor particles, so I can't explain them.

That's because everyone knows that the current theories are flawed -- they make a few wrong predictions, fail to make other predictions, and provide explanations that fundamentally disagree with each other (eg gravity caused by warped spacetime or gravitons) While the new theory should be better, but that does not necessarily mean that it should be more accurate in its predictions. Copernicus' heliocentric theory did not produce more accurate results (some say it was less accurate), yet because of its elegance it was a good theory. (It was, of course, later modified to have elliptical orbits and more accurate results.) Your requirement that any new theories have better predictions is a ban on new theories on this site. If someone had a better theory than the current ones, they would publish in a prestigious peer reviewed journal, rather than in an internet science forum. I think that alternative (even crazy) theories should be allowed here, so that they can be developed or poked full of holes. Surely poking holes in a new theory is more interesting than answering the silly questions that take up half the threads and would be better answered by wikipedia or a quick google search? Surely people learn at least as much from this? I totally agree, and it is also a good learning experience. Perhaps the problem is not with the crazy theories, but with the crazy people who refuse to quit trying to shove a disproven theory/hypothesis down our throats?

Well, you don't actually know anything you didn't know already about the second particle. That is, you already knew its spin was opposite of that of its twin. What bothers me more is how the second particle knows that the first has been measured:confused:

All that the elements "want" from life is to complete their electron shell (so that they look like a noble gas). The closer an element is to the noble gasses from the left (the halogens) the higher the electronegativity, and the farther from the left, the less electronegativity (the alkali metals). This also will help you to understand bonding. Usually, this bonding is sharing pairs of electrons, increasing the effective number of both, but in the more extreme cases (those elements which are just right of the noble gasses mixing with those just to the left of the noble gasses), you can get ionic bonds where one element completely takes away an electron from the other element. I'm not a chemist, so take what I say with a grain of NaCl.

One must also consider that this study is claiming that most studies are false, so if it were true, one should expect this study to be false. This is not unlike the claim that 87.31% of statistics are made up on the spot. Actually, what the study is claiming is that most published studies are false. One problem is that results considered statistically significant are sometimes simply due to coincidence, whereas some results that are true fail to get significant results. Both problems increase with smaller sample size, and also because editors preferentially publish surprising results (which tend to be false) rather than expected results (which tend to be true, but boring). But most of us already know that we should take small sample sizes and unexpected results with a grain of salt, so this is not as big a problem as is claimed.

I think what some are saying is that determinism is unsatisfactory for free will. After all, the choice has effectively been made in advance; anyone with enough computational power could compute what you would choose. And there is no way you could change your mind. Chance likewise is unsatisfactory, besides which it is obvious that we are not completely random. And what manner of choice is the requrement to flip a coin? If that were so, the coin would have free will. Finally, one might consider that free will could be a combination of laws and chance. Yet, if there is no free will to be found in laws and none in chance, where would the free will in this combination come from? Could you write a computer program with a random number generator that would have free will? <Occam Razor mode = off>One might say that chance allows for a loophole into the metaphysical world. If God decided to play dice (apologies to Einstein) and fiddled with the "random" results of quantum mechanics (in such a way that the probabilities remain unchanged, of course), would that not allow for massive yet undetectable control over the physical world? Likewise, if someone's spirit could similarly control the quantum events inside "his" body, you could have someone controlled by a metaphysical spirit, rather than just his brain.</Occam> And yet, even if it were so, scientists would then want to ask, what sort of laws does that metaphysical free follow? One might conclude that free will, as some wish it to be, is completely out of the realm of science. On a more serious note, isn't random chance a total cop-out? Kind of like saying "God did it" but without the metaphysical implications?

Consider evolutionary algorithms http://en.wikipedia.org/wiki/Evolutionary_algorithms These are basically mutation and selection applied to the real world right now. They are, of course, artificial, but there are some good parallels. The information adding part is carried out by the fitness algorithm. Now the fitness algorithm has very little information, but the ability to recognize stuff that gives a good score. Also of interest is the manner in which the system is tuned (mutation rate, intermixing, etc). Bonus: if you have someone who believes God created us through evolution, then our purpose is given by the selection criteria (ie to have as many surviving offspring as possible). So God's most important command would be: "Go forth, and multiply."

Plus, most of the heavier metals (above 92) weren't discovered until various degrees of recently.

I believe that Aggregated Diamond Nanorods are the hardest known substance (they were discovered recently btw). A neutron star is probably "harder" but I would not want to go test. But diamond, and I think also the nanorod form, will shatter if you hit it with a hammer. If you could make a composite of diamond nanorods and carbon nanotubes, it would probably be pretty tough. I think carbon is the strongest material possible (by weight), because it is the lightest element that can form 4 bonds. Anyone know if this is true?

Like what swansont said. Think of the two wheels as spinning tops. They add stability in the same way. Also like the flywheels in spacecraft.