It's not a programmer thing; just look at the comments to the Wall Street Journal article and you'll find the same complaints. I find that pedantry is mostly a class issue. The educated upper classes (and those who see themselves as such) use pedantry to place themselves above others they view as lower class and uneducated ("begging the question" being a perfect example). You will never hear complaints about Bostonians who don't pronounce "r" (*Pahk the cah in Hahvahd Yahd."); you will hear endless complaints about black people who say "ax" instead of "ask" (even though "ax" is actually the original pronunciation). The Boston accent is perceived as cosmopolitan and part of a historic American tradition. African-American vernacular is saddled with poverty and ghetto stereotypes by those outside the communities.
By definition, "improper" English is how poor people speak.
This depends on the possible quality and size of a universe simulation. Is it possible to simulate the entirety of a universe using only a finite subset of that universe?
If yes, then there are (at maximum) an infinite number of simulated universes and and infinite number of recursively simulated universes. Thus the probability of us being the root/real universe is zero ("of measure zero" if you ask a mathematician). Perhaps the holographic principle comes into play to allow the entire universe to be simulated without using the resources of the entire universe.
If no, then there can be only a finite number of simulations in the observable universe. Also, each of the simulated universes is a smaller and/or less-precise version of the simulating universe. In this case, there are (at maximum) a finite number of simulated universes and a finite number of recursively simulated universes capable of hosting intelligent life (a cellular automata with only one cell could hardly be called intelligent). In this scenario, there is a non-zero probability that we live in the root/real universe.
I lean towards no, but I don't have any evidence, just a bias for thinking myself real.
True, in a contracting universe, photons gain energy. Noether's theorem says that energy conservation is a consequence of time translation symmetry (t -> t + constant), not reversal symmetry (t -> -t), so conservation of energy isn't required. The "energy imbued by the creation of the universe" seems ill-defined. If you believe Hawking and Krauss, this energy is zero.
Read the blog post I linked to above. There's no way to consistently assign an energy density to spacetime curvature. Quoting Prof. Carroll:
[U]nlike with ordinary matter fields, there is no such thing as the density of gravitational energy. The thing you would like to define as the energy associated with the curvature of spacetime is not uniquely defined at every point in space. So the best you can rigorously do is define the energy of the whole universe all at once, rather than talking about the energy of each separate piece. (You can sometimes talk approximately about the energy of different pieces, by imagining that they are isolated from the rest of the universe.) Even if you can define such a quantity, it’s much less useful than the notion of energy we have for matter fields.
Consider the region of space that contains the photon. If each dimension of the universe double in size, then the photon loses half its energy. But, the vacuum energy increases by a factor of 8 (volume increases by 8 since space is 3 dimensional). This process can't keep energy constant.
You can also reason that different photons will lose different amounts of energy depending on the energy they started with. There's nothing to keep these changing energies balanced with the vacuum energy in expanding or contracting space.
It has been known for quite some time that energy is difficult to define rigorously in General Relativity. A good explanation can be found in this post by CalTech physicist Sean Carroll. Key point:
The point is pretty simple: back when you thought energy was conserved, there was a reason why you thought that, namely time-translation invariance. A fancy way of saying “the background on which particles and forces evolve, as well as the dynamical rules governing their motions, are fixed, not changing with time.” But in general relativity that’s simply no longer true. Einstein tells us that space and time are dynamical, and in particular that they can evolve with time. When the space through which particles move is changing, the total energy of those particles is not conserved.
As a simple example, imagine a photon traveling through an expanding universe in a region with no other matter or energy (dark or otherwise). The expansion of space stretches the wavelength of the photon (cosmological redshift, which is distinct from Doppler redshift), causing it to lose energy. The photon loses energy with nothing around it gaining. Energy is lost because spacetime itself is changing, so Noether's theorem doesn't apply.
"Copacetic" is a perfectly fine word. It's just very rarely used. A native speaker would only use it to show off that they know the word. Other examples: peripatetic and callipygian.
How do you let people know what the compiler does? Unless there's a human-readable spec, people can't plan for future code/contracts. Writing random code/contracts and seeing if it "compiles" is not a great way to program/negotiate.
Doing the same thing every time is only a prerequisite for being correct. What if most people don't like what the current compiler does? After editing, how do you let people know what changed? How do you even know the compiler is correct without a human-verifiable document of expected behavior?
If a new version of the compiler comes out, does that mean that all previous versions were interpreting code incorrectly? Is there any existing compiler that behaves correctly?
I second this. KPhotoAlbum was specifically made for fast tagging. Tagging 1,000 images with places, people, interesting things, etc., in half an hour is pretty normal for a session. As for lock-in, your image tags are kept in an all-text XML file. I run it off of Gnome and XFCE and don't notice any problems.
No exception. Rule #1 is broken by reviving old forms and rules, usually with a Neo- prefix. First examle that comes to mind is Stravinsky's Neoclassical period. Compare The Rite of Spring (which gave birth to the Modern period of classical music) to his Italian Suite, which was the first of his Neoclassical pieces, written seven years later.
Rotating the nut clockwise always moves it away from you; rotating it counter-clockwise always moves the nut towards you. You're flipping your position axes (looking from the top/bottom) but keeping your velocity axes the same (moving in the same direction), hence the direction of rotation flips.
Mostly quantum mechanics. The fact that an electron can only exist at certain distances from the nucleus has to do with its wave properties. It's similar to how there is a minimum frequency that a guitar string can vibrate at due to its length, tension, and mass. Due to the forces and energies involved, there is a minimum distance that an electron can exist from a nucleus.
However, sometimes that minimum distance lies inside the nucleus. The element mercury (among others) can capture one of its own inner electrons. A proton reacts with the electron to form a neutron and a neutrino. Mercury minus one proton is gold.
The summary and articles are a little vague about what the "shape" of an electron is supposed to be. As are as we know, an electron is a point particle, meaning it has zero size. What these scientists mean by "spherical" is that the electron's electric field is perfectly spherically symmetric (measured to a higher degree of accuracy than any previous measurement). This means that if you imagine a sphere with an electron at the center, then the electric field of the electron is exactly the same magnitude over the entire surface of the sphere. If the electron had a dipole component, as many supersymmetric theories predict, then the electric field of the electron would be stronger on one side of the imaginary sphere. The scientists did not measure any dipole component.
Yes, we might finally get a court ruling that the Civil Rights Act is blatantly unconstitutional because it infringes on the property owner's right to refuse service to anyone for *any* reason, and the resulting crazy would be fun to watch from the other side of the ocean.
I'd like to know where in the Constitution this right is established.
The only physics bit that bugged me was the tether scene. Spoilerish. Two astronauts tied together falling past a structure, once one of them grabs on and withstands the shock of the other astronaut snapping the tether taut, he should rebound back towards the secured astronaut, not dangle as if still being pulled by gravity. This would not be the case if, say, they were on a rotating structure or on a rocket making a significant burn but neither is the case.
[More Spoilers] I've seen this film twice now, and I think I know what was happening. The astronauts were swinging in an arc on the tethers. The force pulling Clooney away was centrifugal force. Even after catching him, their momentum would still be carrying them sideways, requiring more centripetal force than the loose straps around Bullock's legs could provide.
This explanation is insufficient. If neutrinos were indeed massive particles we'd see a wide distribution of their velocities, just like we can observe slow and fast protons, slow and fast electrons, slow and fast everything that moves slower than c. Yet, in 100% of experiments that have been done all neutrinos are propagating through space at the speed close to or exactly equal to c.
The reason for this is the extremely small mass of neutrinoes. The current experimentally-derived upper bounds on their mass is around 1 eV (in contrast, an electron has a mass of 511,000 eV). This means that any process that creates a neutrino will give it enough energy to send it off at ultrarelativistic speeds. Even something simple like neutron decay can impart 1 MeV of kinetic energy to a neutrino, which, as the grandparent calculates, means the neutrino is traveling at 0.999999999999*c. Only chemical reactions would release a small enough amount of energy to have non-relatvistic neutrinos. But, chemical reactions don't release neutrinos.
This is why we only see speed-of-light neutrinos. This is also why it's taken so long to discover that they have mass.
If it were up to me, I'd prefer that Martian life had no relation to life on Earth. Two results from this:
1) It will give us new information on the kinds of life that can exist (Is it carbon-based? Does it need water?). Similarities add constraints on how life must be; differences remove them. 2) It will all but prove that life is plentiful in the universe. If life independently emerged twice in the same solar system, then wherever it is possible for life to exist, it will be found.
The new result, from Yitang Zhang of the University of New Hampshire in Durham, finds that there are infinitely many pairs of primes that are less than 70 million units apart...
This means that for every prime p such that p+q (where q is less than 70 million) is also prime, there exists another prime r bigger than p such that r+s (where s is also less than 70 million) is also prime. Note that there is no limit to the distance between p and r.
You might want to try Manjaro Linux. It's based on Arch, so it's a rolling release, but they have their own repositories for testing updated packages before release. Plus, their installer is much less of a hassle than Arch's, including an automatic graphics card driver installer.
Slashdot Mirror
A quick search says either Germany or Belgium: http://en.wikipedia.org/wiki/N...
It's not a programmer thing; just look at the comments to the Wall Street Journal article and you'll find the same complaints. I find that pedantry is mostly a class issue. The educated upper classes (and those who see themselves as such) use pedantry to place themselves above others they view as lower class and uneducated ("begging the question" being a perfect example). You will never hear complaints about Bostonians who don't pronounce "r" (*Pahk the cah in Hahvahd Yahd."); you will hear endless complaints about black people who say "ax" instead of "ask" (even though "ax" is actually the original pronunciation). The Boston accent is perceived as cosmopolitan and part of a historic American tradition. African-American vernacular is saddled with poverty and ghetto stereotypes by those outside the communities.
By definition, "improper" English is how poor people speak.
Here are a few words from a posh Brit on the matter.
This depends on the possible quality and size of a universe simulation. Is it possible to simulate the entirety of a universe using only a finite subset of that universe?
If yes, then there are (at maximum) an infinite number of simulated universes and and infinite number of recursively simulated universes. Thus the probability of us being the root/real universe is zero ("of measure zero" if you ask a mathematician). Perhaps the holographic principle comes into play to allow the entire universe to be simulated without using the resources of the entire universe.
If no, then there can be only a finite number of simulations in the observable universe. Also, each of the simulated universes is a smaller and/or less-precise version of the simulating universe. In this case, there are (at maximum) a finite number of simulated universes and a finite number of recursively simulated universes capable of hosting intelligent life (a cellular automata with only one cell could hardly be called intelligent). In this scenario, there is a non-zero probability that we live in the root/real universe.
I lean towards no, but I don't have any evidence, just a bias for thinking myself real.
There is no Doppler effect for a single photon, unless that photon is emitting other photons.
True, in a contracting universe, photons gain energy. Noether's theorem says that energy conservation is a consequence of time translation symmetry (t -> t + constant), not reversal symmetry (t -> -t), so conservation of energy isn't required. The "energy imbued by the creation of the universe" seems ill-defined. If you believe Hawking and Krauss, this energy is zero.
Read the blog post I linked to above. There's no way to consistently assign an energy density to spacetime curvature. Quoting Prof. Carroll:
Consider the region of space that contains the photon. If each dimension of the universe double in size, then the photon loses half its energy. But, the vacuum energy increases by a factor of 8 (volume increases by 8 since space is 3 dimensional). This process can't keep energy constant.
You can also reason that different photons will lose different amounts of energy depending on the energy they started with. There's nothing to keep these changing energies balanced with the vacuum energy in expanding or contracting space.
Note that the linked blog post was in response to another Arxiv Blog article that makes the same mistake.
It has been known for quite some time that energy is difficult to define rigorously in General Relativity. A good explanation can be found in this post by CalTech physicist Sean Carroll. Key point:
As a simple example, imagine a photon traveling through an expanding universe in a region with no other matter or energy (dark or otherwise). The expansion of space stretches the wavelength of the photon (cosmological redshift, which is distinct from Doppler redshift), causing it to lose energy. The photon loses energy with nothing around it gaining. Energy is lost because spacetime itself is changing, so Noether's theorem doesn't apply.
"Copacetic" is a perfectly fine word. It's just very rarely used. A native speaker would only use it to show off that they know the word. Other examples: peripatetic and callipygian.
How do you let people know what the compiler does? Unless there's a human-readable spec, people can't plan for future code/contracts. Writing random code/contracts and seeing if it "compiles" is not a great way to program/negotiate.
Doing the same thing every time is only a prerequisite for being correct. What if most people don't like what the current compiler does? After editing, how do you let people know what changed? How do you even know the compiler is correct without a human-verifiable document of expected behavior?
If a new version of the compiler comes out, does that mean that all previous versions were interpreting code incorrectly? Is there any existing compiler that behaves correctly?
When will the questions stop?
I second this. KPhotoAlbum was specifically made for fast tagging. Tagging 1,000 images with places, people, interesting things, etc., in half an hour is pretty normal for a session. As for lock-in, your image tags are kept in an all-text XML file. I run it off of Gnome and XFCE and don't notice any problems.
No exception. Rule #1 is broken by reviving old forms and rules, usually with a Neo- prefix. First examle that comes to mind is Stravinsky's Neoclassical period. Compare The Rite of Spring (which gave birth to the Modern period of classical music) to his Italian Suite, which was the first of his Neoclassical pieces, written seven years later.
It was skipped; that's a comment in Python. The return statement is all the code needed.
Rotating the nut clockwise always moves it away from you; rotating it counter-clockwise always moves the nut towards you. You're flipping your position axes (looking from the top/bottom) but keeping your velocity axes the same (moving in the same direction), hence the direction of rotation flips.
Those aren't much help to the people already infected.
Mostly quantum mechanics. The fact that an electron can only exist at certain distances from the nucleus has to do with its wave properties. It's similar to how there is a minimum frequency that a guitar string can vibrate at due to its length, tension, and mass. Due to the forces and energies involved, there is a minimum distance that an electron can exist from a nucleus.
However, sometimes that minimum distance lies inside the nucleus. The element mercury (among others) can capture one of its own inner electrons. A proton reacts with the electron to form a neutron and a neutrino. Mercury minus one proton is gold.
http://en.wikipedia.org/wiki/E...
http://en.wikipedia.org/wiki/M...
The summary and articles are a little vague about what the "shape" of an electron is supposed to be. As are as we know, an electron is a point particle, meaning it has zero size. What these scientists mean by "spherical" is that the electron's electric field is perfectly spherically symmetric (measured to a higher degree of accuracy than any previous measurement). This means that if you imagine a sphere with an electron at the center, then the electric field of the electron is exactly the same magnitude over the entire surface of the sphere. If the electron had a dipole component, as many supersymmetric theories predict, then the electric field of the electron would be stronger on one side of the imaginary sphere. The scientists did not measure any dipole component.
Yes, we might finally get a court ruling that the Civil Rights Act is blatantly unconstitutional because it infringes on the property owner's right to refuse service to anyone for *any* reason, and the resulting crazy would be fun to watch from the other side of the ocean.
I'd like to know where in the Constitution this right is established.
The only physics bit that bugged me was the tether scene. Spoilerish. Two astronauts tied together falling past a structure, once one of them grabs on and withstands the shock of the other astronaut snapping the tether taut, he should rebound back towards the secured astronaut, not dangle as if still being pulled by gravity. This would not be the case if, say, they were on a rotating structure or on a rocket making a significant burn but neither is the case.
[More Spoilers]
I've seen this film twice now, and I think I know what was happening. The astronauts were swinging in an arc on the tethers. The force pulling Clooney away was centrifugal force. Even after catching him, their momentum would still be carrying them sideways, requiring more centripetal force than the loose straps around Bullock's legs could provide.
This explanation is insufficient. If neutrinos were indeed massive particles we'd see a wide distribution of their velocities, just like we can observe slow and fast protons, slow and fast electrons, slow and fast everything that moves slower than c. Yet, in 100% of experiments that have been done all neutrinos are propagating through space at the speed close to or exactly equal to c.
The reason for this is the extremely small mass of neutrinoes. The current experimentally-derived upper bounds on their mass is around 1 eV (in contrast, an electron has a mass of 511,000 eV). This means that any process that creates a neutrino will give it enough energy to send it off at ultrarelativistic speeds. Even something simple like neutron decay can impart 1 MeV of kinetic energy to a neutrino, which, as the grandparent calculates, means the neutrino is traveling at 0.999999999999*c. Only chemical reactions would release a small enough amount of energy to have non-relatvistic neutrinos. But, chemical reactions don't release neutrinos.
This is why we only see speed-of-light neutrinos. This is also why it's taken so long to discover that they have mass.
If it were up to me, I'd prefer that Martian life had no relation to life on Earth. Two results from this:
1) It will give us new information on the kinds of life that can exist (Is it carbon-based? Does it need water?). Similarities add constraints on how life must be; differences remove them.
2) It will all but prove that life is plentiful in the universe. If life independently emerged twice in the same solar system, then wherever it is possible for life to exist, it will be found.
"I don't want to achieve immortality by copying my brain to the cloud. I want to achieve immortality by not dying!"
-- adapted from Woody Allen
Not quite.
This means that for every prime p such that p+q (where q is less than 70 million) is also prime, there exists another prime r bigger than p such that r+s (where s is also less than 70 million) is also prime. Note that there is no limit to the distance between p and r.
You might want to try Manjaro Linux. It's based on Arch, so it's a rolling release, but they have their own repositories for testing updated packages before release. Plus, their installer is much less of a hassle than Arch's, including an automatic graphics card driver installer.