So what? I never walk through the town's park, because it's too far away from my home. So I pay taxes for a service I never use. I drive with the bicycle along the river path to work, but I pay taxes for road maintenance. I throw away unread the leaflets with the special offers of my local supermarket, but it pays for them with the revenue it makes also from my shopping. Or to come back to the restaurant analogy: I don't salt my food, but I still have to pay for the salt on my table. I don't eat the salad leaf on my steak, but I still have to pay for it. I've never used the cassette player in my car stereo, but I paid for it. Just because you don't use a service you get thrown in with the other services you pay for doesn't allow you to refuse payment at all.
The big difference between your examples is that corporations are not generally in the business of providing parks or maintaining streets.
No? Never driven on a private road? Never been in a privately owned park?
I can't just understand why you want to forbid a certain entity to provide a service. A town is in charge to maintain a certain quality of life within its bounds. Quality of life means lots of things: having clean streets, attracting business, create zones for recreation, plan urbanization, provide security for persons and property. Most of those things are paid for by taxes. Or did you ever get a bill from your police department "patrolling at 3.45am through the neigbourhood: $15"? A town is in a certain way in the business of making it agreable to live in. It is in this business in competition with other places, with other towns. Everyone is calling for free markets and free competition and in the same sentence is heavily regulating the ways a town can do its business. Normally this should be the matter of the citizen's vote, how the town has to do its business. Why can a restaurant offer its customers WiFi without additional charge, but a town is forbidden to offer the same service? That's schizophrene. When the restaurant does it, and the internet café in the neighborhood loses business, because it's charging for WiFi, that's ok. When the town is offering the service, and the telco loses business, the so called free market guys are crying foul. To me exactly those people never understood the idea of a free market at all, because they want to exclude participants from the market, just because they fear they might have an influence on prices other participants can charge. Do you want to forbid a computer store to distribute free T-shirts as advertisement, just because the clothes store might lose business?
And no one has the right to have a green park or cleaned streets in downtown or whatever public services are there. And don't tell me you don't live downtown and have to pay your gardener or the cleaning lady! Sometimes it's just a good idea from a town to offer a service for free, even though you don't use it. If a mayority in a town wants to have municipal WiFi, then let them have their way. If it gets too expensive for your wallet to pay the taxes, move somewhere else. Sheesh!
First: It is nearly impossible to automatically convert a single thread application into a multithreading one. Multithreading requires a lot of things to be guaranteed that aren't in a single thread application. One of the most important is dealing with reentrance: What happends if two threads are running the same code at nearly the same time and try to access the same global variable? Which goes first? Which writes the result first, which last? What happens if the first thread later wants to read from the global variable again and the second thread has changed the contents? Is it possible to have the global variable twice, one for each thread? Or would that destroy the semantics, and in the end you are having just the same program running twice (which is quite different from having the program run in parallel on different cores, speeding up the execution twofold). Maybe a compiler can spot complete data independence between two different parts of the program and put them in different threads. Also the compiler could be part of the operating system as a type of on-the-fly-compiler, compiling machine code into itself (or into micro ops for the special processor, like the Transmeta processor does in hardware) and again spot data independence. But there is no guarantee this will really speed up the program execution. What if the newly found threads are never used at the same time? Then they will be still executed serially. Imagine the single threaded program as a single rail track. You can't just increase the transporting capacity by having two trains running on the single track. You have to build new tracks to let the trains cross each other. And you have to design a schedule to take advantage of the different trains arriving at about the same time at the crossing point. But there is hope: In a multi tasking environment like all modern operating systems there is nearly never only a single task running at a given time. A single threaded program would profit from a multi core machine that it will probably run exclusively on a single core, where all other task are sharing the other cores, if it is demanding enough (that means: if it runs with high enough priority to go always first if the OS has to decide which task now gets the next free core).
As I said: It was developed in analogy. But the word creation is completely logical and according to the rules of the source language. If a table were you get books from a library (this time the latin word libra = book) is a bibliotheque, then a table were you play records in disc shape is a discotheque. There are other words newly created for old language: photography (from photon = light and graphein = to write), geology (from gaea = earth and logos = word, lesson), telescope (from telos = far away and skopein = to see). None of those words were existent when the ancient greeks were talking to each other. But still: Those are greek words.
This was the easiest way to do it. "Lied in his resume" is easy and accepted at every court, even though it might not have been a prerequisite for his job. I guess the whole NASA staff just waited for a single thing to pop up.
Discus is greek for plate, and theke is also greek for table. A discotheque is a table with plates on, in this case the table of the disc jockey. It has indirectly to do with the bibliotheque, the table for books (biblio: greek for book).
Indeed the latin word virus (slime, poison, venom) is the source for today's word virus. The problem is that the latin virus is a singularitantum, a word that only exists in singular, because it doesn't describe a countable entity. There is no correct latin plural for virus at all. When the word 'virus' was used to describe something that was causing sickness and was not really alive for itself (like bacterias are), the word was used for the phenomen. Later one it was recognized that there are single countable entities contained in the poisonous slime, but then the name already stuck. Finding the correct plural for 'virus' looks a little like finding the correct vocative for 'ego'.
The special thing about a Moebius ribbon is the fact that it doesn't have orientation, left and right are the same. The fact, that it is a closed loop is less interesting. There are also unlimited mathematical objects with Moebius property.
There is a group of crabs called Sacculinae, which do the same to the crabs they are parasiting on.
The sacculina is a barnacle which grows on (or rather below) other crabs, squeezing and growing its so called rhizocephalae into the body of the host crab and trying to reach the brain of the crab. After the brain is reached, the host crab turns into a zombie, reacting on each command from the sacculina, even searching for a mate for the sacculina.
The costs of a defense measure should be too much more expensive than the costs for circumventing the defense measure. I guess having the rockets zig-zagging to the target is cheaper than trying to precalculate their route and send a warhead where they might go to to hit them and destroy.
The whole missile defense only works because you know where the missile is going to. For a purely reactive device (like a heat seeker missile) the ballistic missiles are just too fast.
It's the same game again like with the S.D.I. of the 80ies. The whole laser based defense system could have been easily defeated by coating the missiles with a reflective surface (e.g. with chrome), thus increasing the required power to blow them up easily about 20 times (an 98% reflective surface just absorbs 2% of the power of a laser beam, whereas a normal coating will take about 20-40%).
That entity no longer exists. The treaty was useless since the collapse of the Soviet Empire.
Wrong. The Union of Independent States formed after the collapse of the Soviet Union was successor in interest for all treaties and contracts. So the ABM contract was still valid.
If Russia and Turkey, both reaching into both Europe and Asia, are counted as European countries, EU citizens probably are a minority in European countries.
If we look at the geographic definition of Europe (the land limited by the Ural mountains, the Caucasus mountains, the Mediterranean and the Atlantic), then most of the Turks don't live in Europe (and those, who do, live mainly in Istanbul and Edirne, maybe 5 to 7 mio, many of the inhabitants of Istanbul live in the asian part of the town though). The european part of Russia has about 100 mio inhabitant. The next big non EU land in Europe is the Ukraine (~60 Mio inhabitants), then Belarus (don't know exactly, 20 mio?), all the others mostly in the Balkan region: Croatia, Serbia-Montenegro, Bosnia-Herzegowina, Albania, Romania, Bulgaria, Moldova maybe 40 Mio to 50 Mio together. All the other non members are either very small states: Monaco, Andorra, San Marino, Liechtenstein, Vatican (which has a special state because of the contracts with Italy). Switzerland and Norway have another 7 mio resp. 3 mio inhabitants. So there are maybe 250 Mio non-EU europeans, still considerably less than in the EU (and with all Turks and Russians, even if they live in Asia, we are still at less than 350 mio).
Because most of the countries in Africa are very poor (the cross domestic product of Africa is about the same size than Belgium, Netherlands and Luxemburg together, and South Africa accounts for about 40% of it), it is not a big market for new computers. Africans often come shopping for used computers and parts to Europe, which wouldn't count towards 'newly sold units'.
Also many people of the Balkan and East European countries don't have much money to spend on IT investitions. So I guess, the EU accounts for at least 75-80% of the numbers for EMEA.
No. I am from a former communist country, and I recognize the signs of a demise for a dictatorship;) I would have given Saddam another two, at maximum three years.
The grandma-slamming type is called 'false positive', the building detonation type is called 'false negative'. False positive are supposed to happen much more often, because many more regular people are checked than really dangerous people. Lets calculate some wild guesses: If the identification is 99.99% correct, and you are checking 1 mio people, of which 10 people are really dangerous, you get 100 false positives and about all dangerous ones (the risk to let one of them slip is only at 1:1000). That means only every tenth person you are slamming on the hood of the police car is really a terrorist. So biometric identification doesn't really need to be that good to perfectly identify one. It should be perfectionated the other way: To really dismiss the data of a not searched person. Back to the example numbers: If the system was able to identify a person 99% for sure, but would be also able to not misidentify a person to 99.9999% (for a tradeoff we basically allow for only a 1:100 chance to identify a person, but make sure that it doesn't falsely identify one by 1:1mio), we would only have 1 person falsely slammed on the car hood, but still were 10:1 sure to not let a suspected terrorist slip.
I'm not so much after letting Bush off the hook as I am in asking what other real ideas of what to do are out there.
What about waiting, drinking tea and look at the Iraqi regime crumble to dust? I would have given the Saddam regime another two years before it would have fallen in. Dictatorship only carries so far, and a dictatorship that isn't even able to cater for the persons supporting it will be dead tomorrow.
The U.S. led invasion took the Iraqi people the chance to help themselves and get rid of their oppressors themselves and be proud of it. Didn't you ever wonder why nearly no one ever cheered for the U.S. troups? Because they were seen as just another foreign force taking foothold in their beloved land.
And about the dead poll: Look at the numbers for the last two years: The yearly account of Iraqis dying by violence is about the same as we know for the worst years of the Saddam rule. I guess for the families there is no difference if their loved ones die from Saddamists or Terrorists or Criminals or as "collateral damage" from military actions against them. The terms are exchangeable. The people are still dead.
This was so in the past, it is now, and it will be in the future.
I can't see any bias against the U.S. there. Get back to me again, when the headline on the NY Times reads: "2534 domestic flights today without any problem".
You are misreading:) 'on behalf of a foreign power' is connected to 'engaged in espionage or international terrorism against the United States', not to 'request judical authorization'.
So FISA is exactly for the cited case:
If you want judical authorization for electronic surveillance and physical search, because you suspect someone to spy or prepare terroristic acts on behalf of a foreign power, then FISA describes the method to get it.
The foreign power is al-Qaida, and the persons suspected are residents or citizens of the U.S. in connection to al-Qaida. That's the perfect case for FISA. And the President didn't invoke FISA, but ordered the wiretapping directly. That's the problem.
When termites build mounds, or beavers build damns, are those interference?
Yes, they are. There are also situations where those interferences kill off whole ecosystems. The main difference between termites or beavers and their constructions and human interference is the impact. In the most cases for each termite mound and for each beaver dam, there are hundreds of square miles without mounds and dams. Human interference is felt at global level, and it is only comparable in impact with the interference chlorophylic plants have to the atmosphere: Turning an atmosphere that is supposed to consist mainly of N2 and CO2 (80:20) into an atmosphere consisting mainly of N2 and O2 (80:20) by taking out about 99,9% of the world's CO2.
If we killed off all chlorophylic plants on earth at once, the level of CO2 would return to 'natural' levels within weeks. Oxygene is reacting with about everything on earth because it is such a strong agence.
No, I am a technician without a formal education:) But I have coded in many different languages, and I found that you can create buffer overflows in about any language you want (Ever destroyed a spreadsheet by looping through cells and writing into the wrong rows?). Sometimes it's not the C equivalent, but having memory that is unaccounted for, is taken without content checking or writing data into places where it overwrites other data used by other routines is always possible. Returning data by reference is often unavoidable, but is prone to be wrongly overwritten.
One-Off-errors are probably the oldest thing in coding, but they still happen. To know that a possible error can be happen doesn't protect you from that error.
1. There is no way to formally prove in general that a program is logically correct. You can prove it formally for single programs, but then you don't have the formal proof, that your proof is formally correct (there are not only bugs in programs, there are also bugs in theorems about programs).
2. A programming environment is either primitive-recursive (and thus very simple and doesn't offer too much for programming) or it is Turing complete and thus capable (in theory) to host every conceivable program. There has been no solution yet for a set of possible programs, which is really smaller than the set of Turing computable programs and still really larger than the set of primitive-recursive programs. It's either Scylla or Charybdis.
3. There is always the problem of covert channels. As long as different entities share the same ressources, they can also communicate to each other. And communication means influence, and influence means not predicted situations which are not tested for (again there is the exception for a primitive subset of programs).
4. The solution to 3. is sandboxing: Creating a closed environment with non-shared ressources. Problem: You can't use it for much, because it is per definitionem not able to communicate to the outside.
5. The same arguments are also telling us that DRM doesn't work. DRM requires problems 1 to 4 to be solved.
Slashdot Mirror
So what? I never walk through the town's park, because it's too far away from my home. So I pay taxes for a service I never use. I drive with the bicycle along the river path to work, but I pay taxes for road maintenance. I throw away unread the leaflets with the special offers of my local supermarket, but it pays for them with the revenue it makes also from my shopping.
Or to come back to the restaurant analogy: I don't salt my food, but I still have to pay for the salt on my table. I don't eat the salad leaf on my steak, but I still have to pay for it. I've never used the cassette player in my car stereo, but I paid for it. Just because you don't use a service you get thrown in with the other services you pay for doesn't allow you to refuse payment at all.
No? Never driven on a private road? Never been in a privately owned park?
I can't just understand why you want to forbid a certain entity to provide a service. A town is in charge to maintain a certain quality of life within its bounds. Quality of life means lots of things: having clean streets, attracting business, create zones for recreation, plan urbanization, provide security for persons and property. Most of those things are paid for by taxes. Or did you ever get a bill from your police department "patrolling at 3.45am through the neigbourhood: $15"?
A town is in a certain way in the business of making it agreable to live in. It is in this business in competition with other places, with other towns. Everyone is calling for free markets and free competition and in the same sentence is heavily regulating the ways a town can do its business. Normally this should be the matter of the citizen's vote, how the town has to do its business. Why can a restaurant offer its customers WiFi without additional charge, but a town is forbidden to offer the same service? That's schizophrene. When the restaurant does it, and the internet café in the neighborhood loses business, because it's charging for WiFi, that's ok. When the town is offering the service, and the telco loses business, the so called free market guys are crying foul. To me exactly those people never understood the idea of a free market at all, because they want to exclude participants from the market, just because they fear they might have an influence on prices other participants can charge.
Do you want to forbid a computer store to distribute free T-shirts as advertisement, just because the clothes store might lose business?
Ok. Let me rephrase: Sometimes it's just a good idea to provide a service without charging the people directly who are actually using it.
And no one has the right to have a green park or cleaned streets in downtown or whatever public services are there. And don't tell me you don't live downtown and have to pay your gardener or the cleaning lady! Sometimes it's just a good idea from a town to offer a service for free, even though you don't use it.
If a mayority in a town wants to have municipal WiFi, then let them have their way. If it gets too expensive for your wallet to pay the taxes, move somewhere else. Sheesh!
First: It is nearly impossible to automatically convert a single thread application into a multithreading one. Multithreading requires a lot of things to be guaranteed that aren't in a single thread application. One of the most important is dealing with reentrance: What happends if two threads are running the same code at nearly the same time and try to access the same global variable? Which goes first? Which writes the result first, which last? What happens if the first thread later wants to read from the global variable again and the second thread has changed the contents? Is it possible to have the global variable twice, one for each thread? Or would that destroy the semantics, and in the end you are having just the same program running twice (which is quite different from having the program run in parallel on different cores, speeding up the execution twofold).
Maybe a compiler can spot complete data independence between two different parts of the program and put them in different threads. Also the compiler could be part of the operating system as a type of on-the-fly-compiler, compiling machine code into itself (or into micro ops for the special processor, like the Transmeta processor does in hardware) and again spot data independence. But there is no guarantee this will really speed up the program execution. What if the newly found threads are never used at the same time? Then they will be still executed serially.
Imagine the single threaded program as a single rail track. You can't just increase the transporting capacity by having two trains running on the single track. You have to build new tracks to let the trains cross each other. And you have to design a schedule to take advantage of the different trains arriving at about the same time at the crossing point.
But there is hope: In a multi tasking environment like all modern operating systems there is nearly never only a single task running at a given time. A single threaded program would profit from a multi core machine that it will probably run exclusively on a single core, where all other task are sharing the other cores, if it is demanding enough (that means: if it runs with high enough priority to go always first if the OS has to decide which task now gets the next free core).
... a team from Memphis, Tennessee, finds a grave near Memphis, Egypt.
As I said: It was developed in analogy. But the word creation is completely logical and according to the rules of the source language. If a table were you get books from a library (this time the latin word libra = book) is a bibliotheque, then a table were you play records in disc shape is a discotheque. There are other words newly created for old language: photography (from photon = light and graphein = to write), geology (from gaea = earth and logos = word, lesson), telescope (from telos = far away and skopein = to see). None of those words were existent when the ancient greeks were talking to each other. But still: Those are greek words.
This was the easiest way to do it. "Lied in his resume" is easy and accepted at every court, even though it might not have been a prerequisite for his job. I guess the whole NASA staff just waited for a single thing to pop up.
For someone who is deutsch (e.g. german), d'oi'tch sounds about right.
No.
Discus is greek for plate, and theke is also greek for table. A discotheque is a table with plates on, in this case the table of the disc jockey. It has indirectly to do with the bibliotheque, the table for books (biblio: greek for book).
Indeed the latin word virus (slime, poison, venom) is the source for today's word virus. The problem is that the latin virus is a singularitantum, a word that only exists in singular, because it doesn't describe a countable entity. There is no correct latin plural for virus at all. When the word 'virus' was used to describe something that was causing sickness and was not really alive for itself (like bacterias are), the word was used for the phenomen. Later one it was recognized that there are single countable entities contained in the poisonous slime, but then the name already stuck. Finding the correct plural for 'virus' looks a little like finding the correct vocative for 'ego'.
The special thing about a Moebius ribbon is the fact that it doesn't have orientation, left and right are the same. The fact, that it is a closed loop is less interesting. There are also unlimited mathematical objects with Moebius property.
Yes. A single Sacculina. And several Sacculinae.
There is a group of crabs called Sacculinae, which do the same to the crabs they are parasiting on.
The sacculina is a barnacle which grows on (or rather below) other crabs, squeezing and growing its so called rhizocephalae into the body of the host crab and trying to reach the brain of the crab. After the brain is reached, the host crab turns into a zombie, reacting on each command from the sacculina, even searching for a mate for the sacculina.
The costs of a defense measure should be too much more expensive than the costs for circumventing the defense measure. I guess having the rockets zig-zagging to the target is cheaper than trying to precalculate their route and send a warhead where they might go to to hit them and destroy.
The whole missile defense only works because you know where the missile is going to. For a purely reactive device (like a heat seeker missile) the ballistic missiles are just too fast.
It's the same game again like with the S.D.I. of the 80ies. The whole laser based defense system could have been easily defeated by coating the missiles with a reflective surface (e.g. with chrome), thus increasing the required power to blow them up easily about 20 times (an 98% reflective surface just absorbs 2% of the power of a laser beam, whereas a normal coating will take about 20-40%).
Wrong. The Union of Independent States formed after the collapse of the Soviet Union was successor in interest for all treaties and contracts. So the ABM contract was still valid.
If we look at the geographic definition of Europe (the land limited by the Ural mountains, the Caucasus mountains, the Mediterranean and the Atlantic), then most of the Turks don't live in Europe (and those, who do, live mainly in Istanbul and Edirne, maybe 5 to 7 mio, many of the inhabitants of Istanbul live in the asian part of the town though). The european part of Russia has about 100 mio inhabitant. The next big non EU land in Europe is the Ukraine (~60 Mio inhabitants), then Belarus (don't know exactly, 20 mio?), all the others mostly in the Balkan region: Croatia, Serbia-Montenegro, Bosnia-Herzegowina, Albania, Romania, Bulgaria, Moldova maybe 40 Mio to 50 Mio together. All the other non members are either very small states: Monaco, Andorra, San Marino, Liechtenstein, Vatican (which has a special state because of the contracts with Italy). Switzerland and Norway have another 7 mio resp. 3 mio inhabitants. So there are maybe 250 Mio non-EU europeans, still considerably less than in the EU (and with all Turks and Russians, even if they live in Asia, we are still at less than 350 mio).
Because most of the countries in Africa are very poor (the cross domestic product of Africa is about the same size than Belgium, Netherlands and Luxemburg together, and South Africa accounts for about 40% of it), it is not a big market for new computers. Africans often come shopping for used computers and parts to Europe, which wouldn't count towards 'newly sold units'.
Also many people of the Balkan and East European countries don't have much money to spend on IT investitions. So I guess, the EU accounts for at least 75-80% of the numbers for EMEA.
No. I am from a former communist country, and I recognize the signs of a demise for a dictatorship ;) I would have given Saddam another two, at maximum three years.
The grandma-slamming type is called 'false positive', the building detonation type is called 'false negative'.
False positive are supposed to happen much more often, because many more regular people are checked than really dangerous people. Lets calculate some wild guesses: If the identification is 99.99% correct, and you are checking 1 mio people, of which 10 people are really dangerous, you get 100 false positives and about all dangerous ones (the risk to let one of them slip is only at 1:1000). That means only every tenth person you are slamming on the hood of the police car is really a terrorist.
So biometric identification doesn't really need to be that good to perfectly identify one. It should be perfectionated the other way: To really dismiss the data of a not searched person.
Back to the example numbers: If the system was able to identify a person 99% for sure, but would be also able to not misidentify a person to 99.9999% (for a tradeoff we basically allow for only a 1:100 chance to identify a person, but make sure that it doesn't falsely identify one by 1:1mio), we would only have 1 person falsely slammed on the car hood, but still were 10:1 sure to not let a suspected terrorist slip.
What about waiting, drinking tea and look at the Iraqi regime crumble to dust? I would have given the Saddam regime another two years before it would have fallen in. Dictatorship only carries so far, and a dictatorship that isn't even able to cater for the persons supporting it will be dead tomorrow.
The U.S. led invasion took the Iraqi people the chance to help themselves and get rid of their oppressors themselves and be proud of it. Didn't you ever wonder why nearly no one ever cheered for the U.S. troups? Because they were seen as just another foreign force taking foothold in their beloved land.
And about the dead poll: Look at the numbers for the last two years: The yearly account of Iraqis dying by violence is about the same as we know for the worst years of the Saddam rule. I guess for the families there is no difference if their loved ones die from Saddamists or Terrorists or Criminals or as "collateral damage" from military actions against them. The terms are exchangeable. The people are still dead.
Only bad news is good news.
Bad news travel fast and far.
This was so in the past, it is now, and it will be in the future.
I can't see any bias against the U.S. there. Get back to me again, when the headline on the NY Times reads: "2534 domestic flights today without any problem".
You are misreading :) 'on behalf of a foreign power' is connected to 'engaged in espionage or international terrorism against the United States', not to 'request judical authorization'.
So FISA is exactly for the cited case:
If you want judical authorization for electronic surveillance and physical search, because you suspect someone to spy or prepare terroristic acts on behalf of a foreign power, then FISA describes the method to get it.
The foreign power is al-Qaida, and the persons suspected are residents or citizens of the U.S. in connection to al-Qaida. That's the perfect case for FISA. And the President didn't invoke FISA, but ordered the wiretapping directly. That's the problem.
Yes, they are. There are also situations where those interferences kill off whole ecosystems. The main difference between termites or beavers and their constructions and human interference is the impact. In the most cases for each termite mound and for each beaver dam, there are hundreds of square miles without mounds and dams. Human interference is felt at global level, and it is only comparable in impact with the interference chlorophylic plants have to the atmosphere: Turning an atmosphere that is supposed to consist mainly of N2 and CO2 (80:20) into an atmosphere consisting mainly of N2 and O2 (80:20) by taking out about 99,9% of the world's CO2.
If we killed off all chlorophylic plants on earth at once, the level of CO2 would return to 'natural' levels within weeks. Oxygene is reacting with about everything on earth because it is such a strong agence.
No, I am a technician without a formal education :) But I have coded in many different languages, and I found that you can create buffer overflows in about any language you want (Ever destroyed a spreadsheet by looping through cells and writing into the wrong rows?). Sometimes it's not the C equivalent, but having memory that is unaccounted for, is taken without content checking or writing data into places where it overwrites other data used by other routines is always possible. Returning data by reference is often unavoidable, but is prone to be wrongly overwritten.
One-Off-errors are probably the oldest thing in coding, but they still happen. To know that a possible error can be happen doesn't protect you from that error.
It goes just more in depth than this:
1. There is no way to formally prove in general that a program is logically correct. You can prove it formally for single programs, but then you don't have the formal proof, that your proof is formally correct (there are not only bugs in programs, there are also bugs in theorems about programs).
2. A programming environment is either primitive-recursive (and thus very simple and doesn't offer too much for programming) or it is Turing complete and thus capable (in theory) to host every conceivable program. There has been no solution yet for a set of possible programs, which is really smaller than the set of Turing computable programs and still really larger than the set of primitive-recursive programs. It's either Scylla or Charybdis.
3. There is always the problem of covert channels. As long as different entities share the same ressources, they can also communicate to each other. And communication means influence, and influence means not predicted situations which are not tested for (again there is the exception for a primitive subset of programs).
4. The solution to 3. is sandboxing: Creating a closed environment with non-shared ressources. Problem: You can't use it for much, because it is per definitionem not able to communicate to the outside.
5. The same arguments are also telling us that DRM doesn't work. DRM requires problems 1 to 4 to be solved.