Play the tape backwards and gravity turns into a repulsive force. That seems to be a time-orientation to me, so what am I missing here?
Throw a stone upwards and catch it as it falls. Play the tape backwards. Can you easily tell apart the throwing from the catching backwards?
What's irreversible is not gravity itself, it's the breakage that happens when something hits the ground in a fall, and that is a thermodynamic phenomenon. When a solid body is smashed to the ground, kinetic energy is converted into heat.
Thermodynamics is one of two sets of phenomena that are irreversible. The other is rather obscure, but is related to the fact that "ordinary" matter seems to be so much more abundant in our universe than anti-matter.
All other phenomena in our universe are reversible in time, which raises an interesting question: are we unable to see the future because our brains work on thermodynamic operations?
Not only biologic brains, but digital computers also depend on non-reversible operations. A two-input AND gate has a "0" output in three different input conditions: "00", "01", and "10". Now imagine a computer that uses a reversible logic system that is reversible, would that computer have a time-symmetric operation?
But you can tell them to perform preventative maintenance like fluid changes, etc.
Tell that to people who have grown used to clicking on icons and expecting everything to work just like magic.
And if something does not work as expected blame the third-party device driver.
Car maintenance is something like "tail/var/log/messages". Preventive maintenance is installing rkhunter and chkrootkit. That's what mechanics do, not the owner.
These "content providers" should realize that publishing content is like releasing oxygen in the atmosphere.
Imagine a farmer that wants to profit from the oxygen his plants release. He could build a greenhouse to capture the oxygen and sell bottled oxygen to customers that agree to pay his price. But that would need investment in the greenhouse and the oxygen bottling equipment. Instead of investing money to get a profit, he releases the oxygen in the atmosphere and lobbies to get a law forcing people have oxygen meters installed in their lungs, so they can pay for the oxygen they consume.
The entertainment industry is like that greedy farmer. To get a profit from their creations, they should invest in an infrastructure of theaters so they can charge entrance to allow people to see their shows. Instead of this they want to release their products in the internet and demand that other people take charge of metering how their products are consumed.
Once the ISPs are having trouble maintaining their REAL services for their users just because some non-sense law bullies them into this filtering, they will take action to change the law.
One of the main differences between rich countries and poor countries is how the law is regarded by the population.
In developed countries there is a general sentiment among the people that obeying the law is something that benefits everybody. In the Third World the general sentiment is that the law is something created by those in power for their own benefit.
The way things are going, expect a major increase in corruption and violence in the currently rich contries in the next decades. You cannot keep creating law after law that go against the wishes of the majority of the people without unwanted consequences.
1) Programming in Python is faster than in C, and Python lets you use C libraries where performance is needed. Python will not make C go away, but will let it be used where it's really needed.
2) Python is more secure and much more powerful than PHP. With a programming environment like Django, Turbo Gears, or Zope, Python can easily do anything PHP can, but PHP is not even near to doing everything Python can do.
The classic is issuing notes, but with blanks left in "so you have to pay attention". Result: lecturer flies through material and nobody pays him any attention while they try to find and copy down the blanks. Grrr.
I had a teacher who did that, but not in math, he was a History teacher. Actually, he went a step further, he issued no printed notes at all, the students had to write down everything. Being too lazy to do that, I bought a textbook.
Nothing helps you get over an anxiety problem like people telling you you're just lazy, let me tell you. You're just not working hard enough, stupid!
Well, what if someone *is* lazy? Exercises start at the easiest levels. Chapter 2 is too hard for you? Then you need to do all the Chapter 1 exercises! If you just skip to Chapter 3 and find it too difficult don't blame others.
I guess this explains why so many "first post"s actually aren't...
No, no, you got it wrong!
Posts that claim to be "first" but aren't usually are in the "subitizing range" (you see, I not only did read the fscking summary but also borrowed a link from it).
These people actually have the much feared Reverse Math Anxiety Syndrome (RMAS). People with RMAS suck at dealing with numbers up to four, but are very good with numbers from five upwards. Have you ever seen the 137th post claiming to be first?
Until I have some more data on this, I won't make an assumption on what happened.
It's one thing to watch kids on their bedroom, it's another thing to find an image the kid made on his or her computer. I suppose that's exactly what the FBI wants to find out, who made those images?
These days when people start screaming "Ohmigod! There's pedophiles everywhere!" the school administration should be very careful if they give computers with cameras to the students.
What if a 15-year-old girl sent a picture of herself wearing a bikini to her 16-year-old boyfriend? There would be lots of people claiming the school administration was facilitating the creation and distribution of "child pornography".
I know of studies (sadly in German) that combined many different power sources to a virtual power plant, in a lot of different locations all over Germany
Usually such studies are advocacy papers, presenting things in the most favorable light.
Denmark is the country where wind power is most widely used because of its favorable conditions and, even there, wind farms produce less than 1% of the needed power 20% of the time. This means that even if you spread it over the whole country there are at least two months each year where the total wind power production is negligible.
Even assuming that you have other sources of power, wind is still terribly inefficient. A nuclear power plant typically has a capacity factor of 90%, which means it can produce 90% of its maximum capacity continuously. Hydro power plants have a capacity factor around 50%. Wind generators have a typical capacity factor around 20% to 30%.
Their shadow capacity was about 20%, meaning peak power was 20% above the highest needed levels.
The only power plants reliable enough to achieve that are nuclear. Look at this Wikipedia article to get an idea of what to expect from a given power plant. Fixing numbers to look good in an advocacy paper is one thing, doing it in a practical situation is another.
It's funny how every time a nuclear power plant stops for maintenance it gets reported in newspapers, but so many people forget that wind generators need maintenance, too. Having many small generators means there's a negligible probability of all of them failing at the same time, it's true, but, on the other hand, it means there's a high probability that some of them will be stopped for maintenance at any time.
Having many small generators dispersed over a wide area means that for each maintenance task a team will have to move to a remote place. The time spent moving the maintenance crew will probably be more than that spent doing the actual maintenance for a typical wind farm, so the mean time to repair should be significant.
Where is the harm in covering area with windmills?
First of all, I, for one, object to seeing propellers everywhere I look.
You have to do so much construction everywhere. You have to build them where the wind is, spread out over a large area, which means building roads and transporting construction materials all over the place. This also means dismantling and recycling the units after their useful lifetime, something much easier to do if you power plant is concentrated at one site.
Windmills have to be built with a much higher power handling capacity than other power plants, because wind power is so intermittent. This means a lot more materials are used to build a windmill than a plant to generate the same average power by other means. More copper, more aluminum, more steel is needed.
The generators, being at the top of a tall column in a high wind stress area, need to be made smaller and lighter than usual, so they use rare materials, such as neodymium for the magnets. This means more waste is created in producing the materials needed to make a wind generator than for other types of generators.
A typical wind farm generates 50% of it power during 15% of the time. Even in Denmark, which has almost ideal conditions for wind power, wind generators are idle at least 20% of the time. This means that you still need to build power plants with the largest total capacity you will ever need, a wind plant does not bring any savings in system capacity, only in fuel use.
All in all, although wind power is certainly greener than fossil fuels, it's not the magic solution to all our problems and they are certainly very far from being harmless to the environment.
Subduction zones have the inconvenient that they are potentially like shredders that may crunch your waste and spread it over. A better alternative is to bury it at the bottom of abyssal plains, some of which have been stable for a billion years or more.
Waste enclosed in a glass or ceramic cylinder buried a hundred meters deep in mud that's under 5000 meters of water is as safe as it can get.
2/Having to store waste for over 100000 years is not what someone with any common sense would call 'green'.
As opposed to dumping waste in the atmosphere, like fossil fuel plants do, yes, it *is* "green". Or as opposed to flooding huge areas of land, like hydroelectric power plants do. Or as opposed to covering huge areas with windmills.
What makes nuclear power "green" is how small a footprint the plants have. In a few hectares of land you can produce as much power as covering the whole state with river dams or windmills.
Linux has plenty of native apps to handle what wine might bring
In another thread someone was asking about games. That's a chicken or egg question, why should game companies invest to support Linux if the market is so small? How can Linux grow in the home computing market without games?
Wine is the way out of that dilemma. Having a way to play Windows games on Linux machines will remove one of the obstacles against Linux adoption. Tuxracer is not good enough for everybody...
yes we have been emitting a lot of crap in the air for quite some time. and the world has seemingly been changing. however we are only seeing these changes for a short period of time.
Do the words "exponential growth" ring a bell to you? What about "reaching the limit"? It's like saying we have been pumping a lot of air into that balloon and why should it blow up right now?
have you guys considered what the climate was like in 1813? during the medival era? the classical era?
This is so that I can actually own a house and not bring up my kids in some silly apartment (which is all we could afford if we lived right by work).
If you aren't satisfied with the current setup, then your children have something in common with crack babies: they were born of parents who couldn't afford parenthood.
The writing was on the wall long ago, much before anyone who is a child today was born. Oil will end. If you bet that oil prices wouldn't start rising until after your children were grown up, you bet wrong.
Not having adequate living conditions in locations served by mass transit and not having mass transit in places with adequate living conditions only means too many people like you chose to disregard the inevitable future.
One question for the multipliters reading. Can the theory of Multiplication be falsified?
Twenty is four times five.
Twenty is two times ten.
Twenty is one times twenty.
When Phil Jones says twenty is not six times five, it doesn't mean anything. In fact, to date only the Moonies at the Wash. Times and Fox News consider his statement worthy of repeating. (He said it to the BBC, btw, not known as a bastion of Deniers.)
So my question is this: When will you learn that Science takes hard work, a lot of study, and lots of math (not meth) to understand. If you want to be a climatologist you should learn physics and chemistry and mathematics (lots of math!).
When you do study enough, you will start to get a grasp on the facts. Faith does not, repeat *NOT*, get into it. You can believe as much as you wish that your car will work, if it's broken it will not. You can believe as much as you wish that CO2 does not absorb infrared radiation, but it does.
Global warming is a simple fact. But it takes hard work to understand the details of some simple facts. If you think it's just a question of belief then obviously you aren't doing enough study to understand the simple facts.
a lot of power is lost during transport from the central plant to the consuming device.
Large electric transformers and transmission lines are very efficient. The loss in electric energy transmission is much less than the loss in transporting fossil fuels. Or do you drill the oil and refine the gasoline you use in your own backyard?
Besides, a large fossil fuel burning power plant is more efficient than a vehicle engine. Burning oil or coal in a power plant to move electric vehicles uses less fuel in total than burning fuel in diesel or gasoline powered vehicles.
Slashdot Mirror
Throw a stone upwards and catch it as it falls. Play the tape backwards. Can you easily tell apart the throwing from the catching backwards?
What's irreversible is not gravity itself, it's the breakage that happens when something hits the ground in a fall, and that is a thermodynamic phenomenon. When a solid body is smashed to the ground, kinetic energy is converted into heat.
Thermodynamics is one of two sets of phenomena that are irreversible. The other is rather obscure, but is related to the fact that "ordinary" matter seems to be so much more abundant in our universe than anti-matter.
All other phenomena in our universe are reversible in time, which raises an interesting question: are we unable to see the future because our brains work on thermodynamic operations?
Not only biologic brains, but digital computers also depend on non-reversible operations. A two-input AND gate has a "0" output in three different input conditions: "00", "01", and "10". Now imagine a computer that uses a reversible logic system that is reversible, would that computer have a time-symmetric operation?
It's quite simple.
If you can't read English, here's the audio version.
Tell that to people who have grown used to clicking on icons and expecting everything to work just like magic.
And if something does not work as expected blame the third-party device driver.
Car maintenance is something like "tail /var/log/messages". Preventive maintenance is installing rkhunter and chkrootkit. That's what mechanics do, not the owner.
These "content providers" should realize that publishing content is like releasing oxygen in the atmosphere.
Imagine a farmer that wants to profit from the oxygen his plants release. He could build a greenhouse to capture the oxygen and sell bottled oxygen to customers that agree to pay his price. But that would need investment in the greenhouse and the oxygen bottling equipment. Instead of investing money to get a profit, he releases the oxygen in the atmosphere and lobbies to get a law forcing people have oxygen meters installed in their lungs, so they can pay for the oxygen they consume.
The entertainment industry is like that greedy farmer. To get a profit from their creations, they should invest in an infrastructure of theaters so they can charge entrance to allow people to see their shows. Instead of this they want to release their products in the internet and demand that other people take charge of metering how their products are consumed.
One of the main differences between rich countries and poor countries is how the law is regarded by the population.
In developed countries there is a general sentiment among the people that obeying the law is something that benefits everybody. In the Third World the general sentiment is that the law is something created by those in power for their own benefit.
The way things are going, expect a major increase in corruption and violence in the currently rich contries in the next decades. You cannot keep creating law after law that go against the wishes of the majority of the people without unwanted consequences.
I know you are trolling, but here's the answer:
1) Programming in Python is faster than in C, and Python lets you use C libraries where performance is needed. Python will not make C go away, but will let it be used where it's really needed.
2) Python is more secure and much more powerful than PHP. With a programming environment like Django, Turbo Gears, or Zope, Python can easily do anything PHP can, but PHP is not even near to doing everything Python can do.
Don't worry, your flying car will have one on the instrument panel.
I had a teacher who did that, but not in math, he was a History teacher. Actually, he went a step further, he issued no printed notes at all, the students had to write down everything. Being too lazy to do that, I bought a textbook.
Well, what if someone *is* lazy? Exercises start at the easiest levels. Chapter 2 is too hard for you? Then you need to do all the Chapter 1 exercises! If you just skip to Chapter 3 and find it too difficult don't blame others.
No, no, you got it wrong!
Posts that claim to be "first" but aren't usually are in the "subitizing range" (you see, I not only did read the fscking summary but also borrowed a link from it).
These people actually have the much feared Reverse Math Anxiety Syndrome (RMAS). People with RMAS suck at dealing with numbers up to four, but are very good with numbers from five upwards. Have you ever seen the 137th post claiming to be first?
That's impossible. The AC to which you answered is an incontrovertible proof of Intelligent Design.
Until I have some more data on this, I won't make an assumption on what happened.
It's one thing to watch kids on their bedroom, it's another thing to find an image the kid made on his or her computer. I suppose that's exactly what the FBI wants to find out, who made those images?
These days when people start screaming "Ohmigod! There's pedophiles everywhere!" the school administration should be very careful if they give computers with cameras to the students.
What if a 15-year-old girl sent a picture of herself wearing a bikini to her 16-year-old boyfriend? There would be lots of people claiming the school administration was facilitating the creation and distribution of "child pornography".
To use CATV cable for cat5 all you need to do is you run X-Base-II with L ohms terminators. Or would those be LXXV ohms?
Usually such studies are advocacy papers, presenting things in the most favorable light.
Denmark is the country where wind power is most widely used because of its favorable conditions and, even there, wind farms produce less than 1% of the needed power 20% of the time. This means that even if you spread it over the whole country there are at least two months each year where the total wind power production is negligible.
Even assuming that you have other sources of power, wind is still terribly inefficient. A nuclear power plant typically has a capacity factor of 90%, which means it can produce 90% of its maximum capacity continuously. Hydro power plants have a capacity factor around 50%. Wind generators have a typical capacity factor around 20% to 30%.
The only power plants reliable enough to achieve that are nuclear. Look at this Wikipedia article to get an idea of what to expect from a given power plant. Fixing numbers to look good in an advocacy paper is one thing, doing it in a practical situation is another.
It's funny how every time a nuclear power plant stops for maintenance it gets reported in newspapers, but so many people forget that wind generators need maintenance, too. Having many small generators means there's a negligible probability of all of them failing at the same time, it's true, but, on the other hand, it means there's a high probability that some of them will be stopped for maintenance at any time.
Having many small generators dispersed over a wide area means that for each maintenance task a team will have to move to a remote place. The time spent moving the maintenance crew will probably be more than that spent doing the actual maintenance for a typical wind farm, so the mean time to repair should be significant.
First of all, I, for one, object to seeing propellers everywhere I look.
You have to do so much construction everywhere. You have to build them where the wind is, spread out over a large area, which means building roads and transporting construction materials all over the place. This also means dismantling and recycling the units after their useful lifetime, something much easier to do if you power plant is concentrated at one site.
Windmills have to be built with a much higher power handling capacity than other power plants, because wind power is so intermittent. This means a lot more materials are used to build a windmill than a plant to generate the same average power by other means. More copper, more aluminum, more steel is needed.
The generators, being at the top of a tall column in a high wind stress area, need to be made smaller and lighter than usual, so they use rare materials, such as neodymium for the magnets. This means more waste is created in producing the materials needed to make a wind generator than for other types of generators.
A typical wind farm generates 50% of it power during 15% of the time. Even in Denmark, which has almost ideal conditions for wind power, wind generators are idle at least 20% of the time. This means that you still need to build power plants with the largest total capacity you will ever need, a wind plant does not bring any savings in system capacity, only in fuel use.
All in all, although wind power is certainly greener than fossil fuels, it's not the magic solution to all our problems and they are certainly very far from being harmless to the environment.
Subduction zones have the inconvenient that they are potentially like shredders that may crunch your waste and spread it over. A better alternative is to bury it at the bottom of abyssal plains, some of which have been stable for a billion years or more.
Waste enclosed in a glass or ceramic cylinder buried a hundred meters deep in mud that's under 5000 meters of water is as safe as it can get.
As opposed to dumping waste in the atmosphere, like fossil fuel plants do, yes, it *is* "green". Or as opposed to flooding huge areas of land, like hydroelectric power plants do. Or as opposed to covering huge areas with windmills.
What makes nuclear power "green" is how small a footprint the plants have. In a few hectares of land you can produce as much power as covering the whole state with river dams or windmills.
In another thread someone was asking about games. That's a chicken or egg question, why should game companies invest to support Linux if the market is so small? How can Linux grow in the home computing market without games?
Wine is the way out of that dilemma. Having a way to play Windows games on Linux machines will remove one of the obstacles against Linux adoption. Tuxracer is not good enough for everybody...
Do the words "exponential growth" ring a bell to you? What about "reaching the limit"? It's like saying we have been pumping a lot of air into that balloon and why should it blow up right now?
Yes, we have.
If you aren't satisfied with the current setup, then your children have something in common with crack babies: they were born of parents who couldn't afford parenthood.
The writing was on the wall long ago, much before anyone who is a child today was born. Oil will end. If you bet that oil prices wouldn't start rising until after your children were grown up, you bet wrong.
Not having adequate living conditions in locations served by mass transit and not having mass transit in places with adequate living conditions only means too many people like you chose to disregard the inevitable future.
One question for the multipliters reading. Can the theory of Multiplication be falsified?
Twenty is four times five.
Twenty is two times ten.
Twenty is one times twenty.
When Phil Jones says twenty is not six times five, it doesn't mean anything. In fact, to date only the Moonies at the Wash. Times and Fox News consider his statement worthy of repeating. (He said it to the BBC, btw, not known as a bastion of Deniers.)
So my question is this: When will you learn that Science takes hard work, a lot of study, and lots of math (not meth) to understand. If you want to be a climatologist you should learn physics and chemistry and mathematics (lots of math!).
When you do study enough, you will start to get a grasp on the facts. Faith does not, repeat *NOT*, get into it. You can believe as much as you wish that your car will work, if it's broken it will not. You can believe as much as you wish that CO2 does not absorb infrared radiation, but it does.
Global warming is a simple fact. But it takes hard work to understand the details of some simple facts. If you think it's just a question of belief then obviously you aren't doing enough study to understand the simple facts.
Large electric transformers and transmission lines are very efficient. The loss in electric energy transmission is much less than the loss in transporting fossil fuels. Or do you drill the oil and refine the gasoline you use in your own backyard?
Besides, a large fossil fuel burning power plant is more efficient than a vehicle engine. Burning oil or coal in a power plant to move electric vehicles uses less fuel in total than burning fuel in diesel or gasoline powered vehicles.
Protection against backhoes is a redundant path, not a redundant site.
Not if you have adequate fire protection and it's not an area subject to earthquakes, hurricanes, or floods.
No need to overdesign. Having a well designed system also means complying to a budget.