Point. Let me clarify. Mathematically, they are the same thing. The principle of least action applies in both cases, just the path the minimizes the particular Lagrangian (T - V) (or Hamiltonian (T + V), if you prefer) differs depending on the potential energy. (Both methods are applications of the Calculus of Variations. ) Either way, it is a minimization problem and the same techniques apply. So, as far as I'm concerned, they tend to blend together.
Both follow the path of least resistance. It just happens that most of the time light follows a straight line. A mirage is an example of when light doesn't follow a straight line.
In your statement, "like light and radar waves", I'm going to assume that you meant light within the visible spectrum. Radio waves and microwaves are also light, just outside of the visible spectrum. They both have wavelengths longer than infrared light.
Sorry to jump down your throat, but this is one of my pet peeves.
It is been approx ten years since I had astronomy, but if I remember correctly this is how stars operate:
The stellar furnace operates in several distinct stages where each stage fuses a particular element and the byproduct is the element used in the next stage. The first is hydrogen, the second is helium. The third is the Cargon - Nitrogen - Oxygen cycle (I think this is the third stage). The CNO cycle produces Silicon. This is where things get interesting... Most stars don't get beyond the CNO cycle (they're not massive enough), but those that do start to fuse Silicon. The final stage is Iron, which is only fusable at a net cost of energy (you get less out than you put in). Once, a star starts producing Iron in its core, its death is assured. I believe (here's the part that is foggy), that once a star starts to fuse Silicon into Iron the star begins to collapse. This process only takes about 3 mins total, from starting to fuse Silicon in any great quantity to supernova!
There are a couple stages of collapse, also. The first is an electron degeneracy stage (don't know much about this stage). It provides some outward pressure, and may prevent further collapse. Stars with between 1.4 and 3 solar masses may have enough mass to push beyond the electron degeneracy stage to the neutron degeneracy stage (neutron stars). At this stage, there is enough gravitational pressure to push the electrons in the atoms into their nucleuses. The electrons and protons pair up and become neutrons in a sort of reverse neutron decay. Beyond 3 solar masses, not even the outward pressure of the neutron degeneracy can prevent the star from collapsing into a black hole.
Incedently, I had always heard that a neutron star was between 1.4 and 3 solar masses. So, the fact that the article discusses it requireing less than 1.4 is curious...
According to the Harvard-Smithsonian Center for Astrophysics' article, this is the farthest known planet @ ~1500 parsecs away (50 times farther than any discovered so far).
Actually, iron, and everything above it, is fusible. The issue is that it requires more energy to get them to fuse then is gained by the fusion process. In practice, only one physical process produces enough energy to fuse iron: supernovas. Under those conditions everything above iron is formed. Why do you think we have heavy elements?
They explain it was detected by observing the effects the stars magnetic field has on charged particles. With a magnetic field of 10^15 gauss (vs 1-5 for the sun and the 10 - 50 for the Earth), it was mentioned that it won't just suck change out of your pocket, but rearrange the molecules in your body. Sounds like fun, doesn't it.
Your definitions are correct, but incomplete. The speed of light, c, (and cmed for that matter) are defined as c^2 = e*u (electric permittivity of the substance times the magnetic permeability of the substance). In other words, the speed of light is determined by how well the substance it is travelling through can be influenced by electric and magnetic fields.
To complete the definition:
n^2 = c^2/cmed^2 = (e0 * u0)/(e * u).
(The zeroes indicate that they are in free space.)
Now to the questions: Negative refractivity should be impossible. Both e and u are positive quantities, and if they weren't, the square would make them at the minimum postive imaginary numbers. The problem is that e and u are only scalars if you are working with the prefered direction of the substance. Otherwise, they are 2nd order tensors (3x3 matrices). (e0 and u0 are always scalars.) I am not sure how this would influence the outcome w/o doing the math. But, it may allow for this type of effect.
NASA's been talking about this for over a year now, here and later here. The second article includes a reference to the NASA report about the space elevator. Additionally, it, also, includes details on other propulsion technologies that can come out of this study.
NASA has been working on an alternative to the Solar Sail. The Solar Sail has one major draw back in its design (other than being technically difficult to implement), and that is the farther out in space it goes, the less force is transmitted to it by the solar wind. (Inverse square law.) A geophysicist is currently working on the idea of using a magnetic bubble as a solar sail. The advantage of this approach is that the mag bubble grows as the solar wind decreases. This creates a force that would be relatively constant until the heliopause (the end of the solar winds effective range) is reached.
You could write a wrapper for your sound driver that dumped all of the uncompressed byte code to your harddrive. So, in addition to being setup to fail, as previously stated, it is (somewhat) easily circumventible.
Your talking about the bulk properties of water. As the other respondents have pointed out, a water molecule is a water molecule regardless of the bulk state the water is in. What your missing is that unless the water molecules are close enough together to begin with, they won't be able to form ice. So, there is a chance that there won't be any ice crystals even when it gets cold enough in the region.
Well I feel, not to be redundant, that this was a very good decision. Having free speech win out over every other law in the land is a good thing. Besides, how can you outlaw a prime number?
The exec branch does influence the judicial branch a little by appointing justices that consistently hand down rulings that are in line with the appointing politicians thinking. That said, the DOJ is fully under the control of the president. Who and how they prosecute is up to them. That, also, means that they can work through arbitration, plea bargains, etc. instead of directly through a judge. Ultimately, enforcement is up to the exec branch, and we must live with their interpretation of the law for at least 4 yrs.
Actually, it doesn't take being stung by 1000's of them to kill you. Developing an allergy to them through repeated exposure is what truly will kill you. After only a couple of stings, some people develop an allergy that is not unlike the allergy to bee stings. Good ol anaphalactic shock...
By writing to a particular memory cell, light passing through that location may be polarized differently because of the different magnetic field. This could then be used to verify the particular state it is in. This could be a very fast way to read the memory.
It is our right and duty to question what our gov't does. Rallying around a central leader is a good idea during times of great need. But, even when we rally together we must watch that we aren't trampled in the fervor.
Re:just speking for the geeks that do get some
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I'm sorry you have to hide it. I'm lucky enough to have one that likes p0rn as much as I do.
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Point. Let me clarify. Mathematically, they are the same thing. The principle of least action applies in both cases, just the path the minimizes the particular Lagrangian (T - V) (or Hamiltonian (T + V), if you prefer) differs depending on the potential energy. (Both methods are applications of the Calculus of Variations. ) Either way, it is a minimization problem and the same techniques apply. So, as far as I'm concerned, they tend to blend together.
Both follow the path of least resistance. It just happens that most of the time light follows a straight line. A mirage is an example of when light doesn't follow a straight line.
In your statement, "like light and radar waves", I'm going to assume that you meant light within the visible spectrum. Radio waves and microwaves are also light, just outside of the visible spectrum. They both have wavelengths longer than infrared light.
Sorry to jump down your throat, but this is one of my pet peeves.
It is been approx ten years since I had astronomy, but if I remember correctly this is how stars operate:
... Most stars don't get beyond the CNO cycle (they're not massive enough), but those that do start to fuse Silicon. The final stage is Iron, which is only fusable at a net cost of energy (you get less out than you put in). Once, a star starts producing Iron in its core, its death is assured. I believe (here's the part that is foggy), that once a star starts to fuse Silicon into Iron the star begins to collapse. This process only takes about 3 mins total, from starting to fuse Silicon in any great quantity to supernova!
...
The stellar furnace operates in several distinct stages where each stage fuses a particular element and the byproduct is the element used in the next stage. The first is hydrogen, the second is helium. The third is the Cargon - Nitrogen - Oxygen cycle (I think this is the third stage). The CNO cycle produces Silicon. This is where things get interesting
There are a couple stages of collapse, also. The first is an electron degeneracy stage (don't know much about this stage). It provides some outward pressure, and may prevent further collapse. Stars with between 1.4 and 3 solar masses may have enough mass to push beyond the electron degeneracy stage to the neutron degeneracy stage (neutron stars). At this stage, there is enough gravitational pressure to push the electrons in the atoms into their nucleuses. The electrons and protons pair up and become neutrons in a sort of reverse neutron decay. Beyond 3 solar masses, not even the outward pressure of the neutron degeneracy can prevent the star from collapsing into a black hole.
Incedently, I had always heard that a neutron star was between 1.4 and 3 solar masses. So, the fact that the article discusses it requireing less than 1.4 is curious
According to the Harvard-Smithsonian
Center for Astrophysics' article, this is the farthest known planet @ ~1500 parsecs away (50 times farther than any discovered so far).
Actually, iron, and everything above it, is fusible. The issue is that it requires more energy to get them to fuse then is gained by the fusion process. In practice, only one physical process produces enough energy to fuse iron: supernovas. Under those conditions everything above iron is formed. Why do you think we have heavy elements?
They explain it was detected by observing the effects the stars magnetic field has on charged particles. With a magnetic field of 10^15 gauss (vs 1-5 for the sun and the 10 - 50 for the Earth), it was mentioned that it won't just suck change out of your pocket, but rearrange the molecules in your body. Sounds like fun, doesn't it.
Your definitions are correct, but incomplete. The speed of light, c, (and cmed for that matter) are defined as c^2 = e*u (electric permittivity of the substance times the magnetic permeability of the substance). In other words, the speed of light is determined by how well the substance it is travelling through can be influenced by electric and magnetic fields.
To complete the definition:
n^2 = c^2/cmed^2 = (e0 * u0)/(e * u).
(The zeroes indicate that they are in free space.)
Now to the questions: Negative refractivity should be impossible. Both e and u are positive quantities, and if they weren't, the square would make them at the minimum postive imaginary numbers. The problem is that e and u are only scalars if you are working with the prefered direction of the substance. Otherwise, they are 2nd order tensors (3x3 matrices). (e0 and u0 are always scalars.) I am not sure how this would influence the outcome w/o doing the math. But, it may allow for this type of effect.
NASA's been talking about this for over a year now, here and later here. The second article includes a reference to the NASA report about the space elevator. Additionally, it, also, includes details on other propulsion technologies that can come out of this study.
NASA has been working on an alternative to the Solar Sail. The Solar Sail has one major draw back in its design (other than being technically difficult to implement), and that is the farther out in space it goes, the less force is transmitted to it by the solar wind. (Inverse square law.) A geophysicist is currently working on the idea of using a magnetic bubble as a solar sail. The advantage of this approach is that the mag bubble grows as the solar wind decreases. This creates a force that would be relatively constant until the heliopause (the end of the solar winds effective range) is reached.
DoS attacks can be nasty, but why don't you use something like LaBrea to slow them down a bit?
You could write a wrapper for your sound driver that dumped all of the uncompressed byte code to your harddrive. So, in addition to being setup to fail, as previously stated, it is (somewhat) easily circumventible.
Your talking about the bulk properties of water. As the other respondents have pointed out, a water molecule is a water molecule regardless of the bulk state the water is in. What your missing is that unless the water molecules are close enough together to begin with, they won't be able to form ice. So, there is a chance that there won't be any ice crystals even when it gets cold enough in the region.
So I tried the BBC which I consider just as, if not better, at reporting then the american journalists.
Well I feel, not to be redundant, that this was a very good decision. Having free speech win out over every other law in the land is a good thing. Besides, how can you outlaw a prime number?
The exec branch does influence the judicial branch a little by appointing justices that consistently hand down rulings that are in line with the appointing politicians thinking. That said, the DOJ is fully under the control of the president. Who and how they prosecute is up to them. That, also, means that they can work through arbitration, plea bargains, etc. instead of directly through a judge. Ultimately, enforcement is up to the exec branch, and we must live with their interpretation of the law for at least 4 yrs.
Actually, it doesn't take being stung by 1000's of them to kill you. Developing an allergy to them through repeated exposure is what truly will kill you. After only a couple of stings, some people develop an allergy that is not unlike the allergy to bee stings. Good ol anaphalactic shock...
By writing to a particular memory cell, light passing through that location may be polarized differently because of the different magnetic field. This could then be used to verify the particular state it is in. This could be a very fast way to read the memory.
It is our right and duty to question what our gov't does. Rallying around a central leader is a good idea during times of great need. But, even when we rally together we must watch that we aren't trampled in the fervor.
I'm sorry you have to hide it. I'm lucky enough to have one that likes p0rn as much as I do.