I cannot access the PDF, so that I have to assume the 3 nm/s^2 for 2 ns are correct. That's small, but not hopeless.
The experiment is probably involving a resonating mass, which is tuned to the packet frequency of the LHC. With 2800 packets making one cycle per 90ms, this gives a frequency of about 3 * 10^7 Hz. If the resonator is of sufficient quality, we might get (I am guessing) 10^9 impulses before the oscillation is damped significantly. This amounts to a maximum velocity of the oscillator of 3 * 10^-9 m/s^2 * 2 * 10^-9 s * 10^9 = 6 * 10^-9 m/s. Assuming a harmonic oscillator, that's a displacement of 6 * 10^-9 m/s/(2 * pi * 3 * 10^7 Hz) ~ 3 * 10^-17 m.
This effect is minuscle, but it might be just at the limit of dectability. A significant problem will be the shielding of the detector, because the LHC should generate a lof of 3 * 10^7 Hz noise, which would influence the experiment. Maybe it would pay to use a higher frequency resonator, despite the smaller displacement.
The problem with GWT is that it mixes so badly with other web toolkits. And it is not standardized, being neither fully Java nor JavaScript at all.
If you want to work in a class-oriented fashion for web development, you should probably go the way of JavaScript 2 as implemented by Jangaroo or Mascara. While JavaScript 2 is not finalized yet, we have a good idea of how it must be like from looking at ActionScript 3.
For example, in a lot of financial applications, float would be good enough since 2 decimal places is enough.
Floats are good for 7 decimal places, but in total, starting with the most sinificant digit. That means that even a number like 999999.00 cannot be represented as a float precisely. (If this number can be represented, it is by pure luck and 999999.01 will fail.) Moreover, the rounding errors will be a permanent source of trouble, even for significantly smaller numbers. That said, it is common practice to use integers (of a sufficient size, with 64 bit being enough in most cases) for financial application. Of course, your basic unit is the cent.
Humans, by contrast, take a couple years before they comprehend the simplest words and actions.
Do you have children? While full control of language is not reached for a few years, a child aged one can make itself understood for all practical purposes. It also reacts correctly to simple commands like "Crawl here!" or "Give me the ball!". (If it likes to.) At the age of two, it should be able to speak two-word sentences and have a vocabulary of over 100 words. My personal experience is that as soon as it understands the concept, it understands the word. Of course, individual development varies widely.
MySQL cannot continue reselling licenses to MySQL w/InnoDB
An interesting twist is that MySQL has not been reselling licenses in the recent past. About two months ago, I looked at the MySQL website, but there was no GPLed code to download, no trial to download and no pricing information for a commercial offer. They were advertising that they can provide that cute transactional store, but they were not providing it, probably until a customer asked really really loudly.
It is left as an exercise to the reader to determine how InnoDB felt about that issue.
Example: Airbus' fly-by-wire system, designed to override a pilot when a dangerous decision was made, erroniously concluded a forest was a runway after a very low pass was made over it. Deciding the speed was too high, it cut the engines. Both pilots and something like 18 journalists were killed. Airbus blamed the pilots - a safe decision as the pilots couldn't answer back, being dead and all, and the only one they could have made. Blaming the computer could have put them out of business.
The way I heard this story was that the pilots deliberately flew near stall speed and that simply pulling up was not possible without crashing the plane immediately (which the plane's computer determine correctly). Before the turbines could give the plane a boost, the plane flew into the forest, which slowed it down and sealed its fate.
It may be possible that I am referring to a different incident, though. I think the crash I described happened in France maybe 15 years ago.
...including seeing earth as a tiny sphere in the distance...
Actually, the earth is not quite so tiny when viewed from the moon as one might think. Being about 3.5 times as big in diameter, it shows up 3.5 times bigger on the moon's sky as the moon shows up in the earth's sky. I would think that is quite impressive...
I am going to spend my 100M on somethings else, though. (Once I get them...)
This thread tends to confuse provability with true, a distinction that Godel clarified. Godel's result applies to any interesting formal system, of which logic is one,
Sorry, not unless you clarify what you mean with 'logic'. First-order predicate logic (the logic known to most people who learned some logic and are not mathematicians) is completely formalizable. This is actually the result of Gödels completeness theorem. All true statements are provable. The set of provable theorems remains uncomputable, though.
The continuum hypothesis is that the power set of the integers is equal to the number of points on a line.
No, this is easily proved. The continuum hypothesis is that there are no sets that are larger than the set of integers and smaller than the power set of the set of integers.
In case of contradiction, there is an axiom that can be added to resolve the contradiction.
Not in most logics that we use today. A contradiction means that a statement and its negation can both be proved. But when you add more axioms, the existing contradicting theorems still hold. You can resolve incompleteness, but not contradictions. (Exceptions are logics like default logic that may loose theorems as they gain axioms. Very nonstandard.)
Regarding the limits of Godel's proof, it does not necessarily apply to infinitely large axiom sets.
Indeed it does not. Use all true statements as axioms, then the system is trivially complete. It ceases to be interesting, though.
... it has potential energy, regardless of what it really is. Sounds stupid?
There has been another suggestion for launching things using long cables, which does not work quite the way as the space elevator: Put a moderately long cable in low-earth orbit and spin it in such a way that the lower end just touches the stratosphere and does not move a lot relatively to the earth's surface. Attach an object to that end (by means of a high flying plane or the like). The object will be thrown into space.
The bad thing about this design is that the spinning cable will loose height in the process and must be powered up using rockets. So in the end, you gain very little. But if you could send in mass from the moon cheaply, you could use that to power up the wheel by catching the packet with the spinning cable when it is high up and releasing it near earth.
This requires extreme precision, but at least the law of physics do not stand in the way. You would have to plan for missing the material from the moon, making sure that it will burn up in the atmosphere or dive in the ocean. You will have to make huge advances in egineering, but it is an option if we cannot get at material that is strong enough for a real elevator.
Re:Is there a better URL? The Minoans are fascinat
on
Atlantis Found. Again.
·
· Score: 2, Funny
You know you have been reading/. too long when this appears to you as:
Actually, it doesn't. However far apart those pennies are when you set up the communications, the "remote half" had to travel at most the speed of light to get there. So, you do not get any increase in the total communication speed.
The breakdown of the analogy here is that the remote end cannot determine whether the penny is still spinning, not even by performing a destructive measurement. (It is not spinning after the measurement, but that is not the question.) No faster than light communication, sorry.
I use a router/firewall for a single box. I decided to buy despite the guy at the shop claiming that I do not need one... From the logs, I can see that I do need one.
What I'd like to know though, is the following: Why does this happen with broadband/DSL connections and not with dialup connections of ye olde tyme? At least for me, there were virtually no attacks when I used that 56k-modem. And that is only a few months ago.
Ok, I'll try to explain. I assume that the hypothetical object in near-sun orbit does not have much more surface on the side that shows away from the sun that on the side that faces the sun. (For a long cylindrical object this would not hold, but I assumed that we were talking about a somehow "football-field" shaped object that is flat rather than long.) Note that folding the back side does not really help, because the radiating surface should see the dark sky without obstruction.
I also assumed that more or less all of the energy from the hot side is actually absorbed. (This is probably the case for a Stirling engine. Otherwise, why move so close to the sun?)
If this is the case, then the back side has to be about 900 K hot to radiate that 130 kW/m^2 we talked about earlier. Ok, so the Stirling engine converts some of the 130 W to a usable form of energy, but it leaves plenty of heat through. Even if it gets 90% efficiency, then we are still at about 500 K.
Granted, this is hot, but manageable. But to achieve the given efficiency, we would have to have about 6000 K at the hot side. Unrealistic. Therefore the hot side must be kept at, say, 1500 K, reducing the efficiency and raising the temperature of the cold side.
Just as a note: You will have a high temperature on the *dark* side, too, because you have vent off the excess heat. You simply cannot do that when the body's temperature is near zero.
A more realistic scenario would be a sun facing side that uses mirrors to achieve hot spots with a high temperature and a cold side of 900 K. But as I said, it gets tough material-wise when get that close to the sun. One of Mercury's Lagrange points might be suitably far away, though.
As the power per area grows with the inverse square of the distance, the wattage at 0.1 AU is 100 times that of 1 AU, not 1000 times.
By the way, 100 times the wattage yields more that 3 times the temperature (4th power law). So you get about 900 K instead of 300 K on earth. That precludes solar panels, I guess.
Gerhardt Schroeder, the current Chancellor, is from the major "liberal" opposition party- I forget the name now. For what it is worth, West Germany only had one Chancellor in the postwar era from the opposition party. All the rest were CDU/CSU until the "wiedervereinigung".
Gerhard Schroeder is from the major left-wing party, the SPD (ie., the social democrats). The liberal party would be the FDP. But then again, the meanings of "social" and "liberal" vary quite a lot with your relative location with respect to the Altantic Ocean...
There were actually two chancellors from the SPD: Willy Brandt and Helmut Schmidt.
they're coded to a single frequency and product, not to each instance of the product!
Informative. This might not be sufficient to cool
down a heated geek discussion, though.
People are typically
wearing more than one piece of clothing,
let's say 6, and carry a wallet and shoes, leaving you with 8 frequencies. These may not tell who you are, but they allow tracking you reliably, I'd expect. (Short signal range not accounted for.) E.g. in a supermarket, they can track you until you reach the point of sale, where you hand over your credit card. They are know knowing exactly how long you spend in front of that 40" flatscreen. Expect some ads soon.
More paranoid persons may elaborate on the more evil schemes. Err, of course they won't, because they are paranoid. But that's the general idea.
Only a 50% increase in 5 years? We are very lucky if that turns out correct. Anything below the prediction of Moore's Law (double every 18 months) would be a real surprise to me...
If I only had time to respond to all those fine offers from Nigeria, I would own 850,000,000 (eight hundred fifty million) bits of email already.
Fully agreed. One of the worst things to do is to start taking antibiotics and stop using them as soon as it feels 'somewhat better', for fear of ill effects.
If you use antibiotics, use them for entire period for which they are prescribed. Otherwise, you are giving the stronger bacteria a chance to survive. You don't want to do that.
A worse idea would be to the store remaining antibiotics 'for future use', i.e., self-medication.
The correlation coefficient between IQ and academic success is something like 60%... I believe that high IQ scores correspond to only about a 5% increase in earnings
If have no reason to doubt your numbers, but that would suggest that academic success correlates little, if at all, with earnings. Given the salary surveys (at least here in Germany) I got a totally different impression.
Slashdot Mirror
"Stop Westeners": That's what they said...
Sorry for the typo: Make that 90 microseconds instead of 90ms. The remainder is correct, though.
The experiment is probably involving a resonating mass, which is tuned to the packet frequency of the LHC. With 2800 packets making one cycle per 90ms, this gives a frequency of about 3 * 10^7 Hz. If the resonator is of sufficient quality, we might get (I am guessing) 10^9 impulses before the oscillation is damped significantly. This amounts to a maximum velocity of the oscillator of 3 * 10^-9 m/s^2 * 2 * 10^-9 s * 10^9 = 6 * 10^-9 m/s. Assuming a harmonic oscillator, that's a displacement of 6 * 10^-9 m/s /(2 * pi * 3 * 10^7 Hz) ~ 3 * 10^-17 m.
This effect is minuscle, but it might be just at the limit of dectability. A significant problem will be the shielding of the detector, because the LHC should generate a lof of 3 * 10^7 Hz noise, which would influence the experiment. Maybe it would pay to use a higher frequency resonator, despite the smaller displacement.
The problem with GWT is that it mixes so badly with other web toolkits. And it is not standardized, being neither fully Java nor JavaScript at all.
If you want to work in a class-oriented fashion for web development, you should probably go the way of JavaScript 2 as implemented by Jangaroo or Mascara. While JavaScript 2 is not finalized yet, we have a good idea of how it must be like from looking at ActionScript 3.
"We cannot. They are already launched."
Floats are good for 7 decimal places, but in total, starting with the most sinificant digit. That means that even a number like 999999.00 cannot be represented as a float precisely. (If this number can be represented, it is by pure luck and 999999.01 will fail.) Moreover, the rounding errors will be a permanent source of trouble, even for significantly smaller numbers. That said, it is common practice to use integers (of a sufficient size, with 64 bit being enough in most cases) for financial application. Of course, your basic unit is the cent.
Do you have children? While full control of language is not reached for a few years, a child aged one can make itself understood for all practical purposes. It also reacts correctly to simple commands like "Crawl here!" or "Give me the ball!". (If it likes to.) At the age of two, it should be able to speak two-word sentences and have a vocabulary of over 100 words. My personal experience is that as soon as it understands the concept, it understands the word. Of course, individual development varies widely.
An interesting twist is that MySQL has not been reselling licenses in the recent past. About two months ago, I looked at the MySQL website, but there was no GPLed code to download, no trial to download and no pricing information for a commercial offer. They were advertising that they can provide that cute transactional store, but they were not providing it, probably until a customer asked really really loudly.
It is left as an exercise to the reader to determine how InnoDB felt about that issue.
You will get caught, mind you.
The way I heard this story was that the pilots deliberately flew near stall speed and that simply pulling up was not possible without crashing the plane immediately (which the plane's computer determine correctly). Before the turbines could give the plane a boost, the plane flew into the forest, which slowed it down and sealed its fate.
It may be possible that I am referring to a different incident, though. I think the crash I described happened in France maybe 15 years ago.
Actually, the earth is not quite so tiny when viewed from the moon as one might think. Being about 3.5 times as big in diameter, it shows up 3.5 times bigger on the moon's sky as the moon shows up in the earth's sky. I would think that is quite impressive...
I am going to spend my 100M on somethings else, though. (Once I get them...)
Sorry, not unless you clarify what you mean with 'logic'. First-order predicate logic (the logic known to most people who learned some logic and are not mathematicians) is completely formalizable. This is actually the result of Gödels completeness theorem. All true statements are provable. The set of provable theorems remains uncomputable, though.
The continuum hypothesis is that the power set of the integers is equal to the number of points on a line.
No, this is easily proved. The continuum hypothesis is that there are no sets that are larger than the set of integers and smaller than the power set of the set of integers.
In case of contradiction, there is an axiom that can be added to resolve the contradiction.
Not in most logics that we use today. A contradiction means that a statement and its negation can both be proved. But when you add more axioms, the existing contradicting theorems still hold. You can resolve incompleteness, but not contradictions. (Exceptions are logics like default logic that may loose theorems as they gain axioms. Very nonstandard.)
Regarding the limits of Godel's proof, it does not necessarily apply to infinitely large axiom sets.
Indeed it does not. Use all true statements as axioms, then the system is trivially complete. It ceases to be interesting, though.
I hope that helps, Olaf
There has been another suggestion for launching things using long cables, which does not work quite the way as the space elevator: Put a moderately long cable in low-earth orbit and spin it in such a way that the lower end just touches the stratosphere and does not move a lot relatively to the earth's surface. Attach an object to that end (by means of a high flying plane or the like). The object will be thrown into space.
The bad thing about this design is that the spinning cable will loose height in the process and must be powered up using rockets. So in the end, you gain very little. But if you could send in mass from the moon cheaply, you could use that to power up the wheel by catching the packet with the spinning cable when it is high up and releasing it near earth.
This requires extreme precision, but at least the law of physics do not stand in the way. You would have to plan for missing the material from the moon, making sure that it will burn up in the atmosphere or dive in the ocean. You will have to make huge advances in egineering, but it is an option if we cannot get at material that is strong enough for a real elevator.
The Minoans were probably the real proto-Geeks.
For the record, Uranium 238 has a half live of over 4*10^9 years.
The breakdown of the analogy here is that the remote end cannot determine whether the penny is still spinning, not even by performing a destructive measurement. (It is not spinning after the measurement, but that is not the question.) No faster than light communication, sorry.
What I'd like to know though, is the following: Why does this happen with broadband/DSL connections and not with dialup connections of ye olde tyme? At least for me, there were virtually no attacks when I used that 56k-modem. And that is only a few months ago.
I also assumed that more or less all of the energy from the hot side is actually absorbed. (This is probably the case for a Stirling engine. Otherwise, why move so close to the sun?)
If this is the case, then the back side has to be about 900 K hot to radiate that 130 kW/m^2 we talked about earlier. Ok, so the Stirling engine converts some of the 130 W to a usable form of energy, but it leaves plenty of heat through. Even if it gets 90% efficiency, then we are still at about 500 K.
Granted, this is hot, but manageable. But to achieve the given efficiency, we would have to have about 6000 K at the hot side. Unrealistic. Therefore the hot side must be kept at, say, 1500 K, reducing the efficiency and raising the temperature of the cold side.
I hope that was understandable.
A more realistic scenario would be a sun facing side that uses mirrors to achieve hot spots with a high temperature and a cold side of 900 K. But as I said, it gets tough material-wise when get that close to the sun. One of Mercury's Lagrange points might be suitably far away, though.
As the power per area grows with the inverse square of the distance, the wattage at 0.1 AU is 100 times that of 1 AU, not 1000 times. By the way, 100 times the wattage yields more that 3 times the temperature (4th power law). So you get about 900 K instead of 300 K on earth. That precludes solar panels, I guess.
There were actually two chancellors from the SPD: Willy Brandt and Helmut Schmidt.
Informative. This might not be sufficient to cool down a heated geek discussion, though.
People are typically wearing more than one piece of clothing, let's say 6, and carry a wallet and shoes, leaving you with 8 frequencies. These may not tell who you are, but they allow tracking you reliably, I'd expect. (Short signal range not accounted for.) E.g. in a supermarket, they can track you until you reach the point of sale, where you hand over your credit card. They are know knowing exactly how long you spend in front of that 40" flatscreen. Expect some ads soon.
More paranoid persons may elaborate on the more evil schemes. Err, of course they won't, because they are paranoid. But that's the general idea.
If I only had time to respond to all those fine offers from Nigeria, I would own 850,000,000 (eight hundred fifty million) bits of email already.
Fully agreed. One of the worst things to do is to start taking antibiotics and stop using them as soon as it feels 'somewhat better', for fear of ill effects.
If you use antibiotics, use them for entire period for which they are prescribed. Otherwise, you are giving the stronger bacteria a chance to survive. You don't want to do that.
A worse idea would be to the store remaining antibiotics 'for future use', i.e., self-medication.
If have no reason to doubt your numbers, but that would suggest that academic success correlates little, if at all, with earnings. Given the salary surveys (at least here in Germany) I got a totally different impression.
Do you have a reference?