I'm not sure. They might be doing lots of things that wouldn't be very obvious. They also may have sanitized the whole thing, but can't afford the burden of sanitizing something historically (aka. going back and altering everything in chronological order). It'd be much easier to sanitize the latest code release than clean the CVS source tree.
Agreed, it isn't great form, but then again, it would be a pretty big burden for them to release the entire CVS source.
And I'm not basing that on the ease of transferring the CVS backup over- I'm basing it on the need for them to then sort through, and take out things which are internal to Apple. -> Private comments that are as of yet secret -> Anything that could allow competitors to easily identify/target apple developers... and so on
I'm not sure about that. From what I understand, open source doesn't mean you have to give other people everything verbatim, and explain the changes.
You have to make available the source you based your code on. That's all. Apple would be under no obligation to make modifications publicly available. It's just a bit silly not to contribute back, otherwise they end up working off a completely different source tree, and lose most colateral benefits of having an open-source basis.
Apple might simply plan to let the open-source crowd stay a few months behind their closed source implementation. That way the community still contributes useful bits, but doesn't ever get in Apple' face with competition for users.
Because then you don't need to worry about running 50kV wires in and out of the enclosure which is sealed. That would also *change* the electric field in the enclosure. This is a REALLY elegant way of getting a huge voltage in there. It also makes it pretty easy to regulate. It also makes it easy to mount the mast.
Imagine trying to get a stable 50-100kV step-up DC converter, and slowly ramping it up in a controlled manner (see EMCO HV power supplies. With one end of the wires in a -50 C container, there would be a lot of condensation on the wires. Also, if there was ever an arc, it would kill a whole lot of complicated power supplies.
The point of using the crystal wasn't to save energy. When running experiments, we're about as concerned about saving energy as wasting O2 while breathing (in all fairness, there are some scientific branches concerned with this, but not the majority).
Their setup: The 'crystal' mentioned in the mainstream articles, is a z-cut lithium tantalate crystal (LiTaO3), with the negative axis facing outward onto a hollow copper block. A tiny tungsten probe (80 microns long and 100 nm wide) is then attached to the other crystal face. This probe acts as a tiny mast for the electric field so that there is a powerful electrical field at the tip of the probe. Then there were a bunch of fancy neutron-counters and single-photon counters bundled around it.
What they did: First they added deuterium gas (at 0.7 Pa) and then cooled the crystal down using liquid nitrogen (to 240 K). Then they used a little heater to increase the chamber temperature slowly.
What happened: Less than 3 minutes later, and still below 273 K (0 degrees Celcius), the neutron signal rose above the background level. There were x-rays coming from the probe tip, and a whole bunch of neutrons. After a few more minutes, the electric field was so strong that it caused arcing between the probe tip and the enclosure (because they kept heatingthe crystal, and the field thus kept getting stronger). The arcing stopped the process (and I'd guess it damages the crystal?).
They added a few links in the article to previous papers: a pdf describing the concept they are trying to harness, another pdf with more about how they use the crystals with the deuterium gas, and a brief abstract.
I think this is pretty cool. I bet/hope that before long (within 10 years), this will be powering small extrasolar probes.
Pretty neat stuff. I don't even mind dupe posts when they're on such important stuff.
Sadly enough, I *know* that he didn't paste it from the prompt. But even if he did, shift-enter allows newlines on the prompt without immediately executing the code. (hence, you can write something like the following snippet right on the command line:)
% print the fibonacci sequence t=[0,1]; for i=1:10; t=[t(2),sum(t)]; disp(t); end
And yes, I do include comments right on the command line, because matlab keeps a history of commands, and I tend to go back to copy/paste stuff into new segments of code.
I kid you not, this is real code my supervisor writes.
if(preproct(7) >=thres), for j=size(at,2),at(:,j)=at(:,j)-maa;,for i=1:size(at,1),at(i,j)=(at(i,j))/(stda(i)+.0000000 01);,end,end,end
Note that this is matlab code, where commas are both an end-of-statement indicator (it's also possible to use just a semicolon), and an array index separator. The nice thing about this code, is that I can at least guess where most of the variable names come from. Oh, and there was *no* line break in the original code. Hooray for the avoidance of those wasteful '/n' characters?!?!
To answer the original poster: yes, comments are of vital importance.
Then again, if a program is structured right, things can be organized into sections, each of which is then commented, as opposed to a bunch of seemingly random lines with comments spaced throughout. Sometimes the layout of code, in conjunction with good variable names, is the best possible method of commenting it. The one thing comments are good for is to assure that someone not familiar with the particular language being used, will still understand the purpose of the code.
How about the amount of debris that it could leave in the upper atmosphere as a result of collisions with small orbital junk?
Aside from taking out satellites, its trajectory would most likely be affected by small impacts of earth-bound debris. The solar wind would most likely be disrupted around this massive object. Piles of dust would probably be ejected into a variety of orbits around earth.
Certainly not doomsday material, but probably a serious hindrance to spaceflight and other orbital technologies. Just the possible debris could pose significant risk to a space elevator, assuming we will have built one.
Re:Stitching together? How about Montreal, cut in
on
Satellite Easter Eggs
·
· Score: 1
I think they own the bird itself.
Stitching together? How about Montreal, cut in two
on
Satellite Easter Eggs
·
· Score: 1
Sorry, you're entierly correct. I'm actually a grad student in Chemistry, so that's kind of a sumsumption for me. After all, I'm trying to contribute new ideas to science in exchange for a couple of years of my own time:). I assume that the vast majority of theory we accept right now, will change in substantial ways or be replaced entirely in the future.
I was more referring to periods of substantial discovery in the various fields, not trying to gage the level of completion of our knowledge. After all, every field will continue to advance (indefinitely?).
I disagree, the computational power of a single computer will not likely continue to increase at the same rate.
The problem limiting the number of cores in a single die becomes twofold: heat dissipation and data transfer. Even if we move to huge numbers of processors, we still have the same issues.
Semiconductors must be run at a fairly low temperature to avoid errors. Additional gates and current generates additional heat. Heat dissipation is limited by heat transfer, which is related to surface area. Unless the CPU package grows significantly, or some magical way of getting heat out of the CPU arises, heat prevents potential growth.
This is also a function of making the wires smaller. In addition, joints between different materials change properties when built on a really small scale: so the entire process doesn't get better when we continue to shrink the package.
Data transfer if critical: we can only process the data actually in the CPU. There are a limited number of external connections possible. What's the point of a pentaflop CPU, if you can only squeeze in/out a few megabytes or gigabytes of data per second?
Besides those issues, once we achieve processing power beyond the region Moore's law persists in, we will have difficulty harnessing said power. A radical departure in input/output methods will be necessary to harness calculation power. Whether AI, some kind of ubiquitous computing, or perhaps direct neural connections, it'll probably be quite interesting.
I agree, 40 years is actually pretty short. Most common math was proven hundreds to thousands of years ago. A good portion of physics was known a few hundred years ago. A good portion of chemistry has been around for about 150 years.
What is impressive: he predicted the growth would follow the trend it did, in an area that hadn't really been well-established.
Which leads to a second dilemna: since Moore was heavily involved in the industry that the law describes growth in, did Moore's law follow the natural growth, or the growth match Moore's law because industry decided to follow the law?
That's a really good idea, although I'm not sure it would work because of the extremely small size of the particles. The cyclonic action would work especially well for larger particles (as I understand it, cyclonic vavuum cleaners work through deposition by gravity filtration).
Then again, consumers in the markets you mentioned are probably more interested in PowerMac G5's... IMHO.
I haven't seen any dual-processor PC's of similar price point with the power/slickness of the recent Mac systems... (I'm a recent convert, although I HATED macs for about 10 years, back in the age of the imac. *shudder*)
I don't really trust reviews I read. Mostly because the metrics used for assessing the hardware are generally not clearly understood by the reviewers (or at least not from what is written), or by consumers. The biggest problem in comparing things is coming up with a really good evaluation function.
As for user reviews... they're usually edited, moderated or moved around by vendors to highlight positive reviews. At least that's my impression with the tigerdirect.ca reviews, and a few other online stores.
My review method is usually to wait for a product to be on the market for 6 months, and then do a thorough search on the web for "product X problems". By looking for configuration problems, bugs, lockups, warranty problems and so on, I can usually spot things that are truly flawed. The rest I base on price.
Really good point. Although some people have replied to the effect that it has already been in contact in the Apollo missions, I agree with you that not enough of the adverse surface chemistry is known.
The chemical reactivity of the particles is not the only concern. Due to the quantity of particles (in a wide variety of shapes and sizes), these dust particles might act as catalysts or enzymes when in contact with biological media. The strange mix of rough crystals/minerals involved would probably cause significant additional complications.
Perhaps the dust might be sorted (in a mass spec?) and used in industrial processes?
Someone else suggested (as a wisecrack?) using flypaper, or gluing the dust to paper as an adornment (moon-dust paper, cute).
Actually, that's not a bad idea.
Using sticky paper (like tape, or flypaper), the moon dust could be efficiently captured inside the airlock, regardless of particle size.
Rebeka: I keep running across your slashdot comments. They're usually insightful to a point where I recognize your writing. Do you have a background in chemistry? Thanks for the interesting percepts.
I wonder how this viewpoint isn't more generally expressed by the population of North America.
This continent is becoming a lot like that which we seem to want to avoid.
I wonder if there is a higher level of concern among the tech sector as compared to the general populace?
I wonder if what's next is having obligatory tracking of people. It's already happening with parolees, so when does it begin to happen with more people?
I've expressed my concern at the level of secrecy involved in portable electronics. It's alarming to me that so many devices run code which can't legally be verified to confirm that they perform *only* the tasks we expect.
What *moderate* organizations exist to combat the tricky points of where our society is going? It'd be nice to organize to try to find solutions to the serious governance problems that seem to be brewing.
I think that people with more money generally have less free time than people with less money. This is because they tend to work more. At least in my experience. Although the idea of having more flexible work hours is definitely true...
I think you are missing the point of the media ban. The point of the media ban was to try to preserve an untainted portion of the population as a possible jury pool. Otherwise the tendancy exists that jurors become biased by media coverage.
The completely sealed state of affairs is what is doomed to failure: hence making things closed, and allowing the proceedings to be unveiled shortly afterwards. I think it makes a lot of sense as a solution. As per the idea that the defense might have leaked it, perhaps that's true, or perhaps it's a political thing. I'm not in a position to comment on that.
What's more interesting is that there is a huge line-up to go to the proceedings, and gallery space is limited, so not everyone can actually get in.
Slashdot Mirror
I agree, it'd be great if they did.
Haven't they released the source?
I'm not sure. They might be doing lots of things that wouldn't be very obvious. They also may have sanitized the whole thing, but can't afford the burden of sanitizing something historically (aka. going back and altering everything in chronological order). It'd be much easier to sanitize the latest code release than clean the CVS source tree.
yeah...
but then again, they wouldn't necessarily know exactly what apple would want to sanitize...
Don't get me wrong, I can understand how useful that cvs repository history would be, I'm just not sure that apple is being all that unfair.
Agreed, it isn't great form, but then again, it would be a pretty big burden for them to release the entire CVS source.
And I'm not basing that on the ease of transferring the CVS backup over- I'm basing it on the need for them to then sort through, and take out things which are internal to Apple. -> Private comments that are as of yet secret -> Anything that could allow competitors to easily identify/target apple developers... and so on
What do you think?
It's strange, where should we draw the line for what we expect from private companies?
That they allow fair-use and backup?
That they make file-formats public?
That they go open-source?
That they make all their software free?
That they not make any money?
hmmn...
I'm not sure about that. From what I understand, open source doesn't mean you have to give other people everything verbatim, and explain the changes.
You have to make available the source you based your code on. That's all. Apple would be under no obligation to make modifications publicly available. It's just a bit silly not to contribute back, otherwise they end up working off a completely different source tree, and lose most colateral benefits of having an open-source basis.
Apple might simply plan to let the open-source crowd stay a few months behind their closed source implementation. That way the community still contributes useful bits, but doesn't ever get in Apple' face with competition for users.
Because then you don't need to worry about running 50kV wires in and out of the enclosure which is sealed. That would also *change* the electric field in the enclosure. This is a REALLY elegant way of getting a huge voltage in there. It also makes it pretty easy to regulate. It also makes it easy to mount the mast.
Imagine trying to get a stable 50-100kV step-up DC converter, and slowly ramping it up in a controlled manner (see EMCO HV power supplies. With one end of the wires in a -50 C container, there would be a lot of condensation on the wires. Also, if there was ever an arc, it would kill a whole lot of complicated power supplies.
The point of using the crystal wasn't to save energy. When running experiments, we're about as concerned about saving energy as wasting O2 while breathing (in all fairness, there are some scientific branches concerned with this, but not the majority).
But IANANP either, I'm a chemist.
Except auto-indent doesn't add the line breaks where necessary to get one command per line.
Their setup: The 'crystal' mentioned in the mainstream articles, is a z-cut lithium tantalate crystal (LiTaO3), with the negative axis facing outward onto a hollow copper block. A tiny tungsten probe (80 microns long and 100 nm wide) is then attached to the other crystal face. This probe acts as a tiny mast for the electric field so that there is a powerful electrical field at the tip of the probe. Then there were a bunch of fancy neutron-counters and single-photon counters bundled around it.
What they did: First they added deuterium gas (at 0.7 Pa) and then cooled the crystal down using liquid nitrogen (to 240 K). Then they used a little heater to increase the chamber temperature slowly.
What happened: Less than 3 minutes later, and still below 273 K (0 degrees Celcius), the neutron signal rose above the background level. There were x-rays coming from the probe tip, and a whole bunch of neutrons. After a few more minutes, the electric field was so strong that it caused arcing between the probe tip and the enclosure (because they kept heatingthe crystal, and the field thus kept getting stronger). The arcing stopped the process (and I'd guess it damages the crystal?).
They added a few links in the article to previous papers: a pdf describing the concept they are trying to harness, another pdf with more about how they use the crystals with the deuterium gas, and a brief abstract.
I think this is pretty cool. I bet/hope that before long (within 10 years), this will be powering small extrasolar probes.
Pretty neat stuff. I don't even mind dupe posts when they're on such important stuff.
Sadly enough, I *know* that he didn't paste it from the prompt. But even if he did, shift-enter allows newlines on the prompt without immediately executing the code. (hence, you can write something like the following snippet right on the command line :)
And yes, I do include comments right on the command line, because matlab keeps a history of commands, and I tend to go back to copy/paste stuff into new segments of code.
hehe. Nah, I'm just finishing my Ph.D., and this is a pretty meaningless snippet of data-processing code anyways. He wouldn't care that it's here.
I kid you not, this is real code my supervisor writes.
Note that this is matlab code, where commas are both an end-of-statement indicator (it's also possible to use just a semicolon), and an array index separator. The nice thing about this code, is that I can at least guess where most of the variable names come from. Oh, and there was *no* line break in the original code. Hooray for the avoidance of those wasteful '/n' characters?!?!
To answer the original poster: yes, comments are of vital importance.
Then again, if a program is structured right, things can be organized into sections, each of which is then commented, as opposed to a bunch of seemingly random lines with comments spaced throughout. Sometimes the layout of code, in conjunction with good variable names, is the best possible method of commenting it. The one thing comments are good for is to assure that someone not familiar with the particular language being used, will still understand the purpose of the code.
How about the amount of debris that it could leave in the upper atmosphere as a result of collisions with small orbital junk?
Aside from taking out satellites, its trajectory would most likely be affected by small impacts of earth-bound debris. The solar wind would most likely be disrupted around this massive object. Piles of dust would probably be ejected into a variety of orbits around earth.
Certainly not doomsday material, but probably a serious hindrance to spaceflight and other orbital technologies. Just the possible debris could pose significant risk to a space elevator, assuming we will have built one.
I think they own the bird itself.
How's this: http://maps.google.com/maps?q=montreal+quebec&ll=4 5.493226,-73.574066&spn=0.014205,0.017231&t=k&hl=e n Montreal cut in two
What I'm referring to is silicon microelectronics. Photonics is a completely different field, as is quantum computing.
And yes, they do have overlapping uses, but I'd still consider them apart from Moore's law.
No?
Sorry, you're entierly correct. I'm actually a grad student in Chemistry, so that's kind of a sumsumption for me. After all, I'm trying to contribute new ideas to science in exchange for a couple of years of my own time :). I assume that the vast majority of theory we accept right now, will change in substantial ways or be replaced entirely in the future.
I was more referring to periods of substantial discovery in the various fields, not trying to gage the level of completion of our knowledge. After all, every field will continue to advance (indefinitely?).
I disagree, the computational power of a single computer will not likely continue to increase at the same rate.
The problem limiting the number of cores in a single die becomes twofold: heat dissipation and data transfer. Even if we move to huge numbers of processors, we still have the same issues.
Semiconductors must be run at a fairly low temperature to avoid errors. Additional gates and current generates additional heat. Heat dissipation is limited by heat transfer, which is related to surface area. Unless the CPU package grows significantly, or some magical way of getting heat out of the CPU arises, heat prevents potential growth.
This is also a function of making the wires smaller. In addition, joints between different materials change properties when built on a really small scale: so the entire process doesn't get better when we continue to shrink the package.
Data transfer if critical: we can only process the data actually in the CPU. There are a limited number of external connections possible. What's the point of a pentaflop CPU, if you can only squeeze in/out a few megabytes or gigabytes of data per second?
Besides those issues, once we achieve processing power beyond the region Moore's law persists in, we will have difficulty harnessing said power. A radical departure in input/output methods will be necessary to harness calculation power. Whether AI, some kind of ubiquitous computing, or perhaps direct neural connections, it'll probably be quite interesting.
I agree, 40 years is actually pretty short. Most common math was proven hundreds to thousands of years ago. A good portion of physics was known a few hundred years ago. A good portion of chemistry has been around for about 150 years.
What is impressive: he predicted the growth would follow the trend it did, in an area that hadn't really been well-established.
Which leads to a second dilemna: since Moore was heavily involved in the industry that the law describes growth in, did Moore's law follow the natural growth, or the growth match Moore's law because industry decided to follow the law?
That's a really good idea, although I'm not sure it would work because of the extremely small size of the particles. The cyclonic action would work especially well for larger particles (as I understand it, cyclonic vavuum cleaners work through deposition by gravity filtration).
Then again, consumers in the markets you mentioned are probably more interested in PowerMac G5's... IMHO.
I haven't seen any dual-processor PC's of similar price point with the power/slickness of the recent Mac systems... (I'm a recent convert, although I HATED macs for about 10 years, back in the age of the imac. *shudder*)
I don't really trust reviews I read. Mostly because the metrics used for assessing the hardware are generally not clearly understood by the reviewers (or at least not from what is written), or by consumers. The biggest problem in comparing things is coming up with a really good evaluation function.
As for user reviews... they're usually edited, moderated or moved around by vendors to highlight positive reviews. At least that's my impression with the tigerdirect.ca reviews, and a few other online stores.
My review method is usually to wait for a product to be on the market for 6 months, and then do a thorough search on the web for "product X problems". By looking for configuration problems, bugs, lockups, warranty problems and so on, I can usually spot things that are truly flawed. The rest I base on price.
Really good point. Although some people have replied to the effect that it has already been in contact in the Apollo missions, I agree with you that not enough of the adverse surface chemistry is known.
The chemical reactivity of the particles is not the only concern. Due to the quantity of particles (in a wide variety of shapes and sizes), these dust particles might act as catalysts or enzymes when in contact with biological media. The strange mix of rough crystals/minerals involved would probably cause significant additional complications.
Perhaps the dust might be sorted (in a mass spec?) and used in industrial processes?
Someone else suggested (as a wisecrack?) using flypaper, or gluing the dust to paper as an adornment (moon-dust paper, cute).
Actually, that's not a bad idea.
Using sticky paper (like tape, or flypaper), the moon dust could be efficiently captured inside the airlock, regardless of particle size.
Rebeka: I keep running across your slashdot comments. They're usually insightful to a point where I recognize your writing. Do you have a background in chemistry? Thanks for the interesting percepts.
Francis
I wonder how this viewpoint isn't more generally expressed by the population of North America.
This continent is becoming a lot like that which we seem to want to avoid.
I wonder if there is a higher level of concern among the tech sector as compared to the general populace?
I wonder if what's next is having obligatory tracking of people. It's already happening with parolees, so when does it begin to happen with more people?
I've expressed my concern at the level of secrecy involved in portable electronics. It's alarming to me that so many devices run code which can't legally be verified to confirm that they perform *only* the tasks we expect.
What *moderate* organizations exist to combat the tricky points of where our society is going? It'd be nice to organize to try to find solutions to the serious governance problems that seem to be brewing.
I think that people with more money generally have less free time than people with less money. This is because they tend to work more. At least in my experience. Although the idea of having more flexible work hours is definitely true...
I think you are missing the point of the media ban. The point of the media ban was to try to preserve an untainted portion of the population as a possible jury pool. Otherwise the tendancy exists that jurors become biased by media coverage.
The completely sealed state of affairs is what is doomed to failure: hence making things closed, and allowing the proceedings to be unveiled shortly afterwards. I think it makes a lot of sense as a solution. As per the idea that the defense might have leaked it, perhaps that's true, or perhaps it's a political thing. I'm not in a position to comment on that.
What's more interesting is that there is a huge line-up to go to the proceedings, and gallery space is limited, so not everyone can actually get in.