LISA was in development for quite a few years (10 maybe ?) when it was cancelled. Now that LIGO did find evidence for gravitational waves ESA wants to be at the winner's table, so the bad project is good again.
I remember an article a couple of years back on this subject, and it explained that exascale computing is not feasible unless the energy cost of moving a single bit around goes down from the picojoules range into the femtojoules.
"Data needs to move on interconnects and they found that even using some really cool emerging technology it still cost 1-3 picojoules for a bit to go through just one interconnect level"
The old version of that machine (more than 10 years ago) was using 384 Itaniums with 2GB of RAM per CPU and custom SGI interconnects so that the operating system saw one single memory space an all the CPUs.
No big news here.
It looks like HP wants to take something out of the effort that was put into the whole Itanium business, now that it is being discontinued.
The new version of Cosmos uses x86 CPUs and GPUs as accelerators.
The man is 94 and still active. I remember Hans Bethe's colloquium when he was 94. I tip my hat to these people, they keep on going strong long after they made their major contributions to their fields.
You just have to sample a large enough number of environments (please note, environments, not people) and you may find out that "some" != "few" either. In large cities you are very likely to find people on their phones most of the time, but large cities are not all there is.
As for cars, when I lived in a small town in North America I had to buy a car. I was too restricted without one. When I lived in a large European city with good public transportation I did not drive a car in more than 10 years. Cars are enablers (allow you to get quickly from one place to another), but in some places there are alternative enablers, like public transportation. I am expected to use one or the other, so I cannot tell the boss that I will walk to work.
If you don't like the phone example take the example of a trans-Atlantic trip. Will your boss agree for you to spend 5 days one way by ship, and another 5 days on the way back or will she/he tell you to get on a plane ?
The enabler (plane) has shifted the expectation (the length of the trip reduced from 5 days to 8 hours one way)
I stopped reading when I saw: "Now that the world has become addicted to portable electronics..."
Not one of these authors mention the fact that many people will gladly do without portable electronics, but they have not choice but to use them. The fact that mobile phones are affordable, almost all populated areas have coverage and they enable people to get in touch at any moment, brings the _expectation_ that everyone has a cell phone with then and can be contacted at any moment.
Let's say you live in a large city and you tell your boss "I will check with you when I get to a public phone". Will your boss tell you "OK, check with me when you get to a public phone", or "Get a cell phone" ?
The scourges passed the world shrinks, For a long time peace and populated lands: One will travel safely by air, land, sea and wave, Then the wars stirred up anew. (C I â" 63) They will think they have seen the Sun at night When they will see the pig half-man: Noise, song, battle, fighting in the sky perceived, And one will hear brute beasts talking. (C I â" 64)
... such that it would be amenable to have a simple, self-contained explanation. He avoided the more hairy subjects. He did not go over the structure of the proton, or QCD and try to make those accessible.
And for the more accessible subjects other physicists have done a great job at explaining them as well. Landau and Kitaigorodsky come to mind.
The problems appear when people with no technical background make the decision of which language to use for a particular project. They base their decision on what they heard from friends or on the latest buzzwords. For example Scala is now imposed on some projects simply because of the word going around that it is the latest and greatest thing.
Experienced developers have already agreed that C++ is great for writing libraries. Personally I use it because I can do everything I need with one language. Handling large data trees, SSE optimizations, OpenGL graphics, all in the same language, but these are all one-person projects.
Go to any large organization and look at a C++ code base developed over 20 years by a team of kept to a size of about 50 developers, when each developer spent an average of 2 years on the job. After a while you can identify what different developers tried to learn on the job.
By the way, I saw similar code bases, but developed in Java. They look just as bad as the C++ ones, and the managed environment which prevents crashes makes the bugs more difficult to find.
... when he shot the stag in the head with the cherry kernels, right between the antlers. A year later he saw the stag again with a beautiful cherry tree growing out of its head.
They should hire him.
It will teach commandos how to hitch a ride on a cannon shell too.
The problem with relying on the timing of the pulses is dispersion of the wave packet in interstellar space. Keep in mind that these signals travel hundreds of light years trough interstellar space, which is by no means a perfect vacuum.
Sometimes entire pulses are missing from the signal. Pulsar study groups use computer clusters for the sole purpose of reconstructing the original form of the pulse. For example, the one at McGill Univ. was student-built, but it made it to the (bottom of the) Top 500 list at the time it was built.
A spacecraft has very limited computing power, certainly not of the magnitude required to reconstruct pulses. The signal is very dirty, it would be a bad idea to rely on its timing. The pulses are very regular, "when the signal is good".
Pulsar navigation may allow to determine the direction in which the spacecraft is traveling, but not the actual distance from Earth, unless the spacecraft has traveled very large distances.
A simple example. Last time I checked, Voyager1 was 18 light-hours away from Earth. Now Alpha Centauri is 4 light-years away. Multiply 4 by 365 and then by 24 and divide by 18. That tells us that Alpha Centauri is about 2000 times more distant than Voyager1.
Put two dots on a blackboard, 2 meters apart. The dots represent Earth and Alpha Centauri. Then Voyager1, the spacecraft that has traveled farthest from Earth, is a full 1 millimeter away from the Earth point.
The closest pulsar to Earth is at an estimated distance of about 250 light-years. The pulsars will be very useful to find the direction, but for distance timing radio signals from Earth to the spacecraft remains the best method.
It is well known that chess players try to unsettle their opponents before important matches, and a world championship match is as big as it gets.
However, capitalizing on the fact that the opponent is Russian, the match is played in New York, the fact that it starts immediately after the presidential elections, and that there was a lot of noise about Russia hacking US servers, is quite low. Well below what is expected from a reigning Chess World Champion.
Everyone agrees that China plans their space missions such that they learn the maximum from the current one before planning the next one. The lessons are learned and applied before moving on the next step, hence the result that they are learning the same things on much smaller budgets.
What I am amazed is that the Russians managed to achieve what they did despite the very incompetent political leadership. One highly incompetent (and mostly illiterate) politician used to sit close to the rockets during launches to prove to the engineers that they had nothing to fear, and that they should trust the wisdom of the party.
During the height of the space race with NASA, the Russian engineers were simply informed by the politicians when the next launch will take place, typically on some politically important date. They rarely had more than 2 years to prepare and therefore had to cut a lot of corners to meet the deadline.
1) A lot more people die driving/biking/walking/taking the bus/teleporting/etc over to a friend's place than those sitting in front of a computer. 2) Using Facebook 18 hours a day dumbs down the senses to the point that nothing will give the person a heart attack. 3) Slow metabolism induced by the lack of physical exercise when using Facebook reduces the wear of the vital organs, hence longer life is a given.
Now I will follow Garry Kasparov's advice from his book "How life imitates chess". That one was about articles that explain what type of food is bad for your health, but it applies here a well:
Just wait 6 months for the next study that will prove the opposite.
Slashdot Mirror
LISA was in development for quite a few years (10 maybe ?) when it was cancelled.
Now that LIGO did find evidence for gravitational waves ESA wants to be at the winner's table, so the bad project is good again.
I think we should call that "having a vision".
One guy walks into a store and asks for a pack of cigarettes. As usual, to discourage smoking, there is a warning printed on the pack:
"Smoking causes impotence"
The customer hands back the cigarette pack and tells the store clerk:
"This is disgusting! Can I have a pack on which it says that smoking cause cancer ?"
The name of the supercomputer "Piz Daint" is extremely offensive in many Europen languages.
But it looks like the owners don't care.
I remember an article a couple of years back on this subject, and it explained that exascale computing is not feasible unless the energy cost of moving a single bit around goes down from the picojoules range into the femtojoules.
The closest reference I can find now is:
http://spectrum.ieee.org/tech-...
The relevant part is:
"Data needs to move on interconnects and they found that even using some really cool emerging technology it still cost 1-3 picojoules for a bit to go through just one interconnect level"
The old version of that machine (more than 10 years ago) was using 384 Itaniums with 2GB of RAM per CPU and custom SGI interconnects so that the operating system saw one single memory space an all the CPUs.
No big news here.
It looks like HP wants to take something out of the effort that was put into the whole Itanium business, now that it is being discontinued.
The new version of Cosmos uses x86 CPUs and GPUs as accelerators.
... my clothes are going to be dry any minute now.
Does anyone remember Webvan ?
Or I am the oldest /. reader ?
https://en.wikipedia.org/wiki/...
The man is 94 and still active. I remember Hans Bethe's colloquium when he was 94. I tip my hat to these people, they keep on going strong long after they made their major contributions to their fields.
On Aurora and Solaria life expectancy has hit 350 and nobody seems to worry about it.
You just have to sample a large enough number of environments (please note, environments, not people) and you may find out that "some" != "few" either. In large cities you are very likely to find people on their phones most of the time, but large cities are not all there is.
As for cars, when I lived in a small town in North America I had to buy a car. I was too restricted without one. When I lived in a large European city with good public transportation I did not drive a car in more than 10 years. Cars are enablers (allow you to get quickly from one place to another), but in some places there are alternative enablers, like public transportation. I am expected to use one or the other, so I cannot tell the boss that I will walk to work.
If you don't like the phone example take the example of a trans-Atlantic trip. Will your boss agree for you to spend 5 days one way by ship, and another 5 days on the way back or will she/he tell you to get on a plane ?
The enabler (plane) has shifted the expectation (the length of the trip reduced from 5 days to 8 hours one way)
I stopped reading when I saw: "Now that the world has become addicted to portable electronics ..."
Not one of these authors mention the fact that many people will gladly do without portable electronics, but they have not choice but to use them.
The fact that mobile phones are affordable, almost all populated areas have coverage and they enable people to get in touch at any moment, brings the _expectation_ that everyone has a cell phone with then and can be contacted at any moment.
Let's say you live in a large city and you tell your boss "I will check with you when I get to a public phone".
Will your boss tell you "OK, check with me when you get to a public phone", or "Get a cell phone" ?
... assholes appeared only in recent times. Back then creatures were more civilized.
The scourges passed the world shrinks,
For a long time peace and populated lands:
One will travel safely by air, land, sea and wave,
Then the wars stirred up anew. (C I â" 63)
They will think they have seen the Sun at night
When they will see the pig half-man:
Noise, song, battle, fighting in the sky perceived,
And one will hear brute beasts talking. (C I â" 64)
... such that it would be amenable to have a simple, self-contained explanation. He avoided the more hairy subjects.
He did not go over the structure of the proton, or QCD and try to make those accessible.
And for the more accessible subjects other physicists have done a great job at explaining them as well. Landau and Kitaigorodsky come to mind.
The problems appear when people with no technical background make the decision of which language to use for a particular project. They base their decision on what they heard from friends or on the latest buzzwords. For example Scala is now imposed on some projects simply because of the word going around that it is the latest and greatest thing.
Experienced developers have already agreed that C++ is great for writing libraries. Personally I use it because I can do everything I need with one language. Handling large data trees, SSE optimizations, OpenGL graphics, all in the same language, but these are all one-person projects.
Go to any large organization and look at a C++ code base developed over 20 years by a team of kept to a size of about 50 developers, when each developer spent an average of 2 years on the job. After a while you can identify what different developers tried to learn on the job.
By the way, I saw similar code bases, but developed in Java. They look just as bad as the C++ ones, and the managed environment which prevents crashes makes the bugs more difficult to find.
... when he shot the stag in the head with the cherry kernels, right between the antlers. A year later he saw the stag again with a beautiful cherry tree growing out of its head.
They should hire him.
It will teach commandos how to hitch a ride on a cannon shell too.
... against Ortnoks and Sheevars. Floaters and Snakemen are obsolete.
I am ashamed of my code !
My code is an abomination that must be ejected from the visible universe !
We must send a message that will pass through the Big Crunch that will alert future universes that my code should not exist in any possible future !
Etc.
I am so ashamed.
The problem with relying on the timing of the pulses is dispersion of the wave packet in interstellar space. Keep in mind that these signals travel hundreds of light years trough interstellar space, which is by no means a perfect vacuum.
Sometimes entire pulses are missing from the signal. Pulsar study groups use computer clusters for the sole purpose of reconstructing the original form of the pulse. For example, the one at McGill Univ. was student-built, but it made it to the (bottom of the) Top 500 list at the time it was built.
A spacecraft has very limited computing power, certainly not of the magnitude required to reconstruct pulses. The signal is very dirty, it would be a bad idea to rely on its timing. The pulses are very regular, "when the signal is good".
Pulsar navigation may allow to determine the direction in which the spacecraft is traveling, but not the actual distance from Earth, unless the spacecraft has traveled very large distances.
A simple example. Last time I checked, Voyager1 was 18 light-hours away from Earth. Now Alpha Centauri is 4 light-years away. Multiply 4 by 365 and then by 24 and divide by 18.
That tells us that Alpha Centauri is about 2000 times more distant than Voyager1.
Put two dots on a blackboard, 2 meters apart. The dots represent Earth and Alpha Centauri. Then Voyager1, the spacecraft that has traveled farthest from Earth, is a full 1 millimeter away from the Earth point.
The closest pulsar to Earth is at an estimated distance of about 250 light-years. The pulsars will be very useful to find the direction, but for distance timing radio signals from Earth to the spacecraft remains the best method.
It is well known that chess players try to unsettle their opponents before important matches, and a world championship match is as big as it gets.
However, capitalizing on the fact that the opponent is Russian, the match is played in New York, the fact that it starts immediately after the presidential elections, and that there was a lot of noise about Russia hacking US servers, is quite low.
Well below what is expected from a reigning Chess World Champion.
Disgusting stuff.
Everyone agrees that China plans their space missions such that they learn the maximum from the current one before planning the next one. The lessons are learned and applied before moving on the next step, hence the result that they are learning the same things on much smaller budgets.
What I am amazed is that the Russians managed to achieve what they did despite the very incompetent political leadership. One highly incompetent (and mostly illiterate) politician used to sit close to the rockets during launches to prove to the engineers that they had nothing to fear, and that they should trust the wisdom of the party.
During the height of the space race with NASA, the Russian engineers were simply informed by the politicians when the next launch will take place, typically on some politically important date. They rarely had more than 2 years to prepare and therefore had to cut a lot of corners to meet the deadline.
It is remarkable that they had so few accidents.
... will be that of a book floating in space.
It has the title:
"Postcards from the edge"
Let's review the facts:
1) A lot more people die driving/biking/walking/taking the bus/teleporting/etc over to a friend's place than those sitting in front of a computer.
2) Using Facebook 18 hours a day dumbs down the senses to the point that nothing will give the person a heart attack.
3) Slow metabolism induced by the lack of physical exercise when using Facebook reduces the wear of the vital organs, hence longer life is a given.
Now I will follow Garry Kasparov's advice from his book "How life imitates chess". That one was about articles that explain what type of food is bad for your health, but it applies here a well:
Just wait 6 months for the next study that will prove the opposite.
There is an old example of how scientific proof can be obtained for the conclusion that you actually want.
A scientist puts a flea on the table and shouts at it:
"Jump!"
And the flea jumps.
Then the scientist carefully cuts off the flea's legs, puts it back on the table and shouts:
"Jump!"
And the flea does not jump.
After this, the scientist happily writes down on his notebook:
"After it lost its legs, the flea cannot hear anymore."