How is that going to make Venus cool enough to support Earth life? Without the carbon dioxide in the atmosphere, I could see it becoming slightly cooler, due to the decreased greenhouse effect, but it wouldn't be anything like Earth. It's atmosphere would still be much thicker than Earth's, and it would still recieve more solar radiation than Earth.
Mars is a better candidate for terraforming, in my opinion.
Yes, the popular thought at this time is that d orbitals can be used to explain the bonding in molecules that exceed the octet rule. In this case, the chlorine atom in ClF3 is not sp2 hybridized, but is rather dsp3 hybridized. The s, p, and d valence orbitals of the chlorine atom all mix together to generate 5 hybrid valence orbitals. 2 of these orbitals are "lone pairs", which contain two electrons each. The other 3 orbitals are bonding orbitals and each contains 1 electron from the chlorine atom and 1 electron from the fluorine atom. So yes, you do have to use all 7 electrons from the chlorine atom.
Most people here are most likely familiar with how an atom absorbs a photon. A photon with energy X is absorbed by an electron in orbit around an atom. This electron, now with energy X added to it, jumps to a higher energy state. After another photon with energy X is emitted by that electron, it falls back into its lower energy state once more.
But, once that electron absorbs the photon, what prevents it from re-emitting that same energy as a graviton with energy X instead of a photon with energy X? Neither photons nor gravitons have properties such as lepton number or electric charge which must be conserved. Both of these particles are pretty bare as far as conserved properties are concerned. My guess is that it would have to do with the spin differences between the two particles.
On another note, can an electron in orbit around an atom theoretically absorb a graviton and re-emit it in a similar fashion that some electrons absorb and re-emit photons?
Is there any way to stimulate an excited atom with excess energy X to emit a graviton with energy X?
Say you have a tornado, ranked as F5 on the Fujita scale (318 mph winds), with a funnel diameter equal to 1 mile. This tornado travels towards a nuclear testing facility. At this facility, there is a nuclear device sitting in the middle of a nearby desert, whose energy is rated at 50 megatons (equal to the yield of Tsar Bomba, the largest bomb detonated by mankind). The F5 tornado passes directly over this device, and just as it is sitting right on top of it, the device detonates, creating a gigantic explosion. Does this nuclear explosion destroy the tornado?
I have read that a tornado with a windspeed of merely 200 mph produces 1 billion watts, so you might imagine a funnel with 318 mph winds producing much more power. One might be able to calculate the total kinetic energy of the funnel if they were to consider it to be a cylinder 1 mile wide and 10 miles high (if you consider that the majority of the tornado is hidden within the cloud) composed of air that is moving at the rotating edge with a speed of 318 mph. I don't have the exact figures with me.
Tsar Bomba was detonated at only a 50% yield, producing 50 megatons. Even at half-power, the blast produced 209 quadrillion joules of energy, and generated a mushroom cloud that ascended to 210,000 feet. This hypothetical bomb is equal to Tsar Bomba's half-power.
Is the tornado too powerful to be destroyed by the bomb, or is it easily annihilated? The thunderstorm that produced the tornado could generate as much as 40 trillion watts, which might help stabilize the tornado or produce new ones if the original is destroyed. My personal belief is that the tornado would be destroyed, but it's possible that I'm not considering all the variables, as the atmosphere is a large and complex entity.
I've read that a nuclear bomb stands no chance of destroying a hurricane, by comparison.
The fact that some galaxies recede faster than the speed of light would be evidence enough that it is space that is expanding and not the galaxies moving themselves. Space and time are not bound by the speed of light, and are allowed to exceed it because they are neither matter nor energy. Any object resting on an area of space that is moving (or expanding) faster than light would look like it was moving faster than light itself. Relative to its own surroundings, however, that object is still moving quite subluminally.
Since no amount of energy can push an object faster than c, you can't explain superluminal galactic recession by repulsive energy alone.
I've read much about Robert Lazar (I even own a 1:48 scale model of his claimed flying saucer), and I currently dismiss at least some key points of his claims.
First of all, he claims that element 115 (ununpentium) is a stable element. According to theory, there are certain numbers of nucleons called "magic numbers" which confer a special added stability to the nucleus that possesses them. Examples of such magic numbers for protons are 2, 8, 20, 28, 50, 82, 114, and 126. The atomic number 115 is not one of these numbers. In fact, no odd number is ever a magic number.
The "island of stability", which is a theoretical place in the super-heavy elements where a particular element is much more stable than those before or after it has been predicted. This element is 114, also called ununquadium. However, even an atom of this surprisingly stable element only lasted 30 seconds (as opposed to fractions of a second seen in other super-heavies) before it decayed. If even this unusually stable element decays so quickly, then 115 should decay at an even faster rate, quite contrary to Lazar's claims. It makes no sense to say that 115 is stable.
Secondly, his description of the strong nuclear force makes no sense. He calls it a type of gravity, when in fact, it is much different from gravity. Gravity has an infinite range, the SNF only acts on subatomic levels. Gravity is extremely weak, the SNF is extremely strong. Gravity acts on mass, SNF acts on color or hypercharge. Gravity, as we know it, is only attractive, while the SNF can be attractive or repulsive. The exchange particles of the two forces have much different properties.
An obvious mistake is how he describes the RANGE of the strong nuclear force in 115. He says it extends past the atom's perimeter. In a typical nucleus, the range of the SNF is on the order of 10^-15 meters, while an atomic diameter is on the order of 10^-10 meters. Given Lazar's claims, the SNF in an atom of element 115 somehow has a range that is around 100,000 times larger than what it is typically supposed to be. I find that hard to swallow.
Perhaps he made up the story entirely. Perhaps he really did work at Area S4 but was given flawed information by his superiors there. Perhaps he simply got mixed up and didn't remember things correctly. Or, perhaps he has really stumbled onto some new physics. As of now, I don't believe the craft (if there is one) operates in the way he says it does.
 Are supersymmetric particles (a.k.a. sparticles) predicted to have antiparticle counterparts? Would they be called antisparticles? Could we expect sparticles and antisparticles to annihilate upon interacting with each other?
 Have supersymmetric atoms (maybe called "satoms") predicted? I've heard that some sparticles are predicted to be stable, which might mean they could form stable snuclei, satoms or even smolecules. These satoms wouldn't necessarily be composed of selectrons, sneutrons, and sprotons, would they? How about gluinos, photinos, winos, or zinos?
 I've heard that the Planck Length (1.6 x 10^-35 m) is supposedly the smallest length that makes physical sense. Would this mean that nothing can be smaller than the Planck Length? Relativity seems to contradict that notion. In length contraction, you can theoretically contract an object to a length that is smaller than the Planck Length if you move it fast enough. Would this then refute the Planck Length as being the smallest unit of length, or could it indicate a flaw in Einstein's equations? Perhaps instead of getting asympotically closer to zero size, a moving object will get asympotically closer to the Planck Length, finally equalling the Planck Length when it travels at light speed?
gsmollin, you say that an electromagnetic dipole is required to produce electromagnetic waves. How can this be applied in the case of Cerenkov radiation? If a single charged particle, such as an electron, is sped up faster than light in a particular medium, it will release electromagnetic waves. Since the electron has a single charge, it acts as an electric monopole, and yet produces waves. Were you refering to a magnetic dipole instead of an electric one (electrons have a magnetic dipole)? This stuff is relatively new to me.
Wait a second. Could another gravitational analogy be pulled off with Cerenkov radiation? If an object with mass is sped up past light speed, might it emit gravitational waves, like a charged particle emits EM waves?
I'm wondering if my analogy here is an appropriate one. You know how the electromagnetic force operates, right? It's probably the best understood of the four forces. If my understanding of it is correct, then:
-A stationary charge produces an electric field. -A moving charge produces a magnetic field. -An accelerating charge produces electromagnetic waves.
There have been parallels drawn between the electromagnetic force and the gravitational force. Hence, we might make a similar analogy with gravity:
-A stationary mass produces a gravitational field. -A moving mass produces a gravitomagnetic field (aka frame-dragging). -An accelerating mass produces gravitational waves (uncomfirmed).
Although both gravitational and gravitomagnetic fields have been confirmed, gravitational waves have not yet been detected. They are predicted, however. (PS: I don't particularly like calling it the 'gravitomagnetic' field because it sounds like some kind of unification between gravity and magnetism, which it isn't).
What about the other two forces, the strong nuclear and weak nuclear forces? Can't similar mechanisms exist for them? For the strong nuclear force:
-A stationary hypercharge produces a strong nuclear field. -A moving hypercharge produces a strong "nucleomagnetic" field. -An accelerating hypercharge produces strong nuclear waves.
Weak nuclear force:
-A stationary weak hypercharge produces a weak nuclear field. -A moving weak hypercharge produces a weak "nucleomagnetic" field. -An accelerating weak hypercharge produces weak nuclear waves.
I do believe that "hypercharge" and "weak hypercharge" are the appropriate terms here. So, taking from this, shouldn't a moving proton generate a kind of strong "nucleomagnetic" field, and an accelerating proton generate strong nuclear waves? Shouldn't the same be true for a moving/accelerating electron and its weak nuclear force?
I realize that both the strong nuclear and weak nuclear forces act on very tiny scales, and that their field analogues of magnetism would probably have a similarly short range. So how might we detect such fields? Could we infer them from anomalous particle behavior? For strong nuclear and weak nuclear waves, might we be able to detect them now?
Another question: Is the weak nuclear force attractive, repulsive or both? The other 3 forces possess a kind of attraction and/or repulsion, so shouldn't the weak nuclear force be the same?
Ah, yes. I've been looking for that. Thanks for pointing it out to me!
PiSystems correctly predicted that benzene (C6H6) is colorless, but it also predicted that coronene (C24H12) is colorless too, whereas it is actually yellowish. I supposed that might be due to imperfections in crystal structure, or impurities, though. I think it is supposed to predict a molecule's color in solution anyway, and not necessarily its solid-state color. Strangely, it gives a large number of colors for colored molecules, so I'm not sure what color they are trying to tell me the substance is.
Photons are generally accepted as having a rest mass of zero. However, since they are never actually "at rest", does that mean they do have a true mass? Similarly, do photons ever exhibit gravitational fields? Are mass and energy the exact same thing, or two seperate things that are merely interchangable?
A further photon question regarding gravity: Imagine that you have a sphere that is mirrored on the inside, and the sphere contains light. The mirrored interior is a "perfect" mirror, that reflects all light without absorption, so the light inside bounces around. Since light is composed of bosons, this sphere can be filled with as much light as you want, since bosons can occupy the same space as other bosons. The light inside this sphere obviously contains a certain level of energy. If there is enough energy in this light, will the sphere collapse into a blackhole? Let's say that the sphere has a radius that is smaller than the Schwarzchild Radius of the mass equivalent of the energy of the light inside of it. Does it collapse into a blackhole? Is this light-filled sphere any more massive than the same sphere would be if it was empty?
It is currently believed that neutrinos undergo "oscillations" of a sort, which allows them to transform from one flavor of neutrino into another (i.e. from an electron neutrino to a muon neutrino or tauon neutrino).
My question: doesn't this violate conservation of lepton number?
For example, take the decay of a muon into an electron, an electron antineutrino, and a muon neutrino. The lepton numbers before the decay are: muon number 1, electron number 0 and tauon number 0. After the decay, the lepton numbers are still the same: muon number 1, electron number 0, tauon number 0. This is conservation of lepton number. However, if that muon neutrino were to transform into a tau neutrino, then the scheme of lepton numbers would change into the following: muon number 0, electron number 0, tauon number 1.
In essence the transformation of one neutrino into another kind of neutrino would change the total universal content of a certain lepton number. Does this mean that lepton number is only approximately conserved, perhaps only in certain interactions or pathways?
The skin secretions produced by many salamanders contain chemicals which discourage predators from eating them. This is because it gives the salamander a bad flavor, or makes it toxic. Another purpose of the secretions is probably to fend off dessication (drying-out). Like many other amphibians, salamanders must keep their skin moist in order to remain healthy. These secretions help keep their skin wet.