we are always feeling the force of gravity, right?
It depends very much on what you mean by "feel" gravity.
On the surface of the earth, the way I use the word "feel", I "feel" the pressure in my legs when I am standing up, and I "feel" the pressure in my butt when I sit down. It "feels" exactly like the floor or seat is pushing me up.
Now, in my usual frame of reference (fixed to the floor), I am not accelerating. But Newton says "F=ma" and I feel a force acting from the floor. How can that be, says the physics student? Well, says the physics guru, there must be *another* mysterious force acting on you to balance out that force that you feel from the floor. I will call that force "gravity". You can measure the magnitude of the force by putting a thing called a "scale" between your feet and the floor, and it will measure the force the floor exerts on the scale, and that the scale exerts on you, (because, after all, the scale isn't accelerating, either, when you use it properly).
The important thing to know is that YOU ARE NOT MEASURING THE GRAVITATIONAL FIELD! What you can measure is the force exerted on the scale, OR, throw something in the air and measure its ACCELERATION in your frame of reference. The only way you can link this to something called "gravity" is to have a *theory* of gravity.
The only way (known to current physics) you could really measure the gravitational field (actually, the curvature of space-time) directly is some very sensitive measurement, for instance, to use optical means to detect curvature of space; in practice, this only works for looking for bright, distant objects behind big things like planets, stars, galaxies, etc. You can also use a big metal resonator to pick up minute vibrations caused by things like stellar explosions. It is no coincidence that these experiments, done by physicists, all are testing something they call the GENERAL THEORY OF RELATIVITY.
This slashdot discussion is a perfect example of "a little knowledge is a dangerous thing." You people all *think* you paid good attention in your Physics 101 class, or whatever, but you didn't really think very hard about what you supposedly learned.
Now, you may have some magic ESP-like power that lets you feel the gravitational field, but I'm guessing not.
How do you know? Imagine an experimental method for determining that a region of space has zero gravitational field (or zero space-time curvature, if you like). How would that method distinguish the zero curvature from free-fall?
Note, in particular, the problem of establishing a "fixed" frame of reference in space-time. Perhaps that is what Einstein was talking about when he called his theory "General RELATIVITY."
You flakes are all getting worked up into a lather about something that is nowhere near as clear-cut as you make it out to be, and a careful consideration of the facts should make that clear to you, if you spent as much effort on asking yourself difficult questions as you do lambasting others.
Note also that it is by no means obvious, for instance, that "looking out the window" of the spacecraft and seeing a planet rotating "below" you means that you are in orbit around the planet. It is only clear if you know that the thing out the window has MASS. How do you really know it has mass? Through gravity? Well, that's a circular argument, isn't it?
In fact, it is easy to imagine that you *could* set up masses around you to cancel out the gravitational fields of every other object. Putting yourself *inside* a massive spherical shell would be a good start. Then, add small lumps to the spherical shell to cancel out the residual effects of far-away bodies.
Einstein's Theory of *General* Relativity includes the Principle of Equivalence, namely,
There is no physical way of distinguishing between a UNIFORM gravitational field from a UNIFORM linear acceleration.
Since there is no way to distinguish between the gravitational field being uniformly *zero* and a uniform acceleration of *zero*, there is no distinguishable difference between your "Zero G Force" (F=ma ---> F=0 a = 0) and "Zero Gravity" (F = 0 because Gmm/r^2 = 0).
Now, the nit to pick that leads to the term "microgravity" is that the gravitational field in Earth orbit is not uniform over a finite region; there are (minute) tidal effects, anisotropies, spacecraft vibration, drag at low earth orbit, etc., all of which are, in principle, detectable, and some of which could not be produced except by a non-uniform gravitational field, although determining that might be beyond a particular experimental error.
Note, in passing, that NASA uses the "Zero Gravity" term to describe it's Earth-based drop facilities.
If you find a 100 years old film sitting in an attic you'll be able to watch it pretty easily
Actually, if you find a 100 year old motion picture, the film base was probably celluose nitrate. After 100 years, there is a very good chance you'll have nothing left but a dark brown, extremely flammable, acidic powder. Even if you have film, it is extremely hazardous and fragile. Hardly "easy."
Even for film that is only 60 years old, it is likely to be on acetate base, which degrades into acetic acid (vinegar), which doesn't provide much support for the emulsion.
Which doesn't even touch the topic of the degradation of color dyes in color film.
No body is trying to take away your little "brother." Maybe he just doesn't want to come live with you. He moved away a *long* time ago, and likes his own home. If he stays away until 2020, you plan to hunt him down?
Again, what gain is there for the people of Taiwan? NONE. The only reason you give is basically to save face for the mainland rulers. If you had non-violent reasons that the Taiwanese would find persuasive, the PRC wouldn't have to keep the military threat alive and install more and more missiles on the mainland which threaten Taiwan.
If you are so big on "trust", why don't you "trust" the people in Taiwan to decide what is right for themselves without bringing military threats into it?
Taiwan has been taking care of itself for the last fifty years and did a hell of a lot better than the Communist party has done with their chance to govern the mainland. They even have this miraculous thing called democracy with truly free, fair, and open elections. In the meantime, every mainland leader talks about "democracy in 50 years" meaning "democracy sometime after I am dead."
Instead, you follow the typical mainlander line of: "we should be husband and wife, so marry me or I'll kill you." No benefits for the Taiwanese mentioned at all. Who would want to take an offer like that?
Twentieth-century physics also gave us the solid state (quantum mechanical) theories needed to understand semiconductor rectification and other phenomena used to make things like, oh, TRANSISTORS. And the atomic physics necessary to make LASERS. So that computer with its CD-ROM drive in front of you wouldn't exist without the efforts of 20th century PHYSICISTS.
None of these were "technologists" working on something they didn't understand, but scientists who actually used the full power of modern physical theories to predict and discover useful phenomena.
And I haven't even reached back to the 19th century to mention a guy by the name of Maxwell, and all the great things made possible by his theoretical research. Like, oh, I don't know, radio.
Even Edison wouldn't have gotten very far if it hadn't been for Ampere, Coulomb, and Faraday. All that funky telegraph stuff that gave Edison his start depended on what was once cutting-edge physics.
I'll freely admit general relativity hasn't (and almost certainly won't) lead to technological breakthroughs. But quantum mechanics has pretty clearly kicked ass.
Most languages which have tail-call elimination ALSO have implementations which put effort into making function calls efficient. Basically, the call is reduced to the same jump that your for-loop solution has anyway.
Whether recursion is "natural" or not depends on the PROBLEM, not the language. Recursion is a natural solution to mapping over a binary tree, for instance. It is the most straightforward solution for factorial and the Fibonacci sequence. You might argue that calculating the Nth member of the Fibonacci sequence is not naturally recursive, although the usual definition of the *sequence* is, because of the extreme redundancy of the computation. (Actually, the Fibonacci sequence is the best example of a recursive solution that is unnaturally inefficient; that's why everyone uses the same example.)
The ability to express a solution in the natural way, of course, does depend strongly on the language.
Code reviews and debugging tools can be used for any language.
The difference is that code reviews, and management resources in general, for more powerful languages can focus more on high-level issues that make a difference, and automated tools can be used for useful end goals such as improving run-time performance and adding features.
While the C++ guys are still crawling around in the dirt playing a game of "who dropped the pointer."
In my experience, the most annoying things are all the electronics-type stuff (EEPROM burners, etc.) that were meant to hang off a parallel port. Vendors typically only provide Windows support, but sometimes a Linux hacker has made an equivalent too, but still using the parallel port hardware.
I keep looking around for something that gives me a USB/Firewire interface to a box which has a bi-directional parallel port, so at least I could adapt all the hacked-up x86 linux clone software on a Mac. But I can never find one.
4) Run your crucial apps a minimum of 4--5 times SLOWER in emulation than a native PC, so that your engineers can waste their precious time (at minimum $50/hour each) waiting for screen refreshes, in order to save you the $500 Windows license.
1) Vital to the success of the products you are engineering
2) Usually the worst citizens in the Windows world, so they are the hardest to emulate.
3) Dwarf Windows in cost.
Who in their right mind is going to run a critical engineering app in an emulator?
1) Run into any issue, call up the CAD vendor and have them say "we don't support running it on anything but real 100% windows....click, dial tone,..."
2) Make critical engineering work depend on the least-used portions of the emulator, written by random open-source jockey, and only lightly tested by the thousands of teenage users who mainly use it to run video games.
3) Save the cost of a $500 Windows license, while still spending $30,000 on a CAD license, and $100+k/year on the engineer. Penny wise, pound utterly stupid.
The most commonly mentioned difficulty is the number of registers in PPC vs. x86. RISC instruction set architectures like PPC tend to have a relatively large number of general purpose registers, vs CISC ISA's which have a smaller number of registers, some of which have special purposes. (CX for count, SI, DI for offset indices,..., my x86 knowledge is VERY stale, so I'll be vague from here on)
In emulation, to keep things fast, you would like to dedicate one hardware register for each emulated register, plus you need hardware registers to actually run the emulator!
A RISC ISA emulating a CISC ISA will enough registers to do so. (r1 = AX, r2 = BX,..., r17..r32 available) The CISC ISA emulating the RISC will tend to
1) need to use the most flexible registers (AX) to run the emulator (e.g. load the RISC opcode from RAM into AX, extract the opcode field, compare it to your opcode table, and dispatch, because AX has the best support for bit operations, let's say)
2) also use the special-purpose registers to run the emulator (e.g. use an index register to index into your opcode tables)
3) leaving too few registers to hold all the emulated registers (oops, we only got r1..r3 in the left over registers; what about r4..r32...)
4) having to use "weak" or wrongly-specialized registers to hold the key RISC registers which are heavily used in the actual RISC program. (E.g., your program is trying to number crunch so it wants to do a lot of floating-point math on data which is being stored in some left-over CISC register which doesn't support floating point natively.)
[note, I'm well aware that x86 is not a CISC hardware implementation under the hood, but to the assembly programmer, it presents a CISC instruction set architecture. Emulating the underlying microcode RISC engine, however, would likely need even more registers, causing the same problems, so you would tend to emulate the CISC model.]
Or, you could recognize all belief is tenative. That as much objective evidence exists for the divinity of the Buddha, for instance, as exists for the divinity of Christ. That just as the truth of Christian scriptures is vehemently believed by Christians, the truth of the Koran is vehemently believed by Muslims.
Which is to say that a truly thoughtful person with religious beliefs ought to be able to empathize with the religious beliefs of others, although they might be quite different.
Although I am a Christian in upbringing, if a Jew tells me his faith requires me to cover my head when I enter a synagogue or attend a Jewish wedding, or for him to abstain from a cheeseburger, I respect that belief, just as I would expect him to respect the doctrine of transubstantiation if I explain it to him. I don't expect him to *believe* in it, but I would expect him to *respect* it.
Unfortunately, there are few truly thoughtful people in the world.
Instead, we get thoughtless people who can simultaneously push to re-introduce prayer into American schools, while decrying the madrassahs of the Mideast for teaching hate and intolerance.
Gosling is not discussing the details of widgets, etc., which make up the (hopefully consistent) USER EXPERIENCE of a graphical user interface; instead, he's concerned with the low-level plumbing which lets multiple applications share the screen and mouse, without having to be aware that other applications have windows which might be overlapping one's own. These problems are totally different, and mostly unrelated.
The widgets that make up the GUI of each application, as well as the lowest-common-denominator graphics tasks could be provided by a single system-wide library that every application would use, to ensure consistency. Gosling is only thinking about how this library would send colored bits to the screen and get mouse clicks from the user.
Quartz doesn't enforce a single user interface, as Apple's own "interface of the year" adventures demonstrate.
Garbage collection means you don't have to use tools that run your program in a sandbox to avoid programming errors which are unfortunately easy to make. Instead, you can spend the time making enhancements and improving performance instead of plugging stupid leaks all day.
Valgrind only fixes memory allocation problems which you can reproduce in a test situation. It doesn't fix memory allocation problems which occur when your application reaches the field and can be subjected to long runs with unpredictable inputs.
Garbage collection IS a modern programming tool. Why are you so afraid of it?
If Apple sold its wares at CostCo, any $500 iMac would sit right next to a $399 Windows machine.
If anyone *did* buy it because daughter Missy thought it was "cuter", they'd bring it home and wonder why why they didn't get the blue-sky-and-clouds when they boot up and why all their pirated software from work wouldn't install on this machine.
The mass market doesn't understand Windows != computer.
Except, if you make the same mistake with a monetary value card, you're out the $1.50 (or is it up to $2 now?) instead of just 18 minutes of your time.
Also, the real problem LTCM had was that a lot of the opportunities that they were trying to exploit involved markets that were rather small and illiquid. Meaning it was impossible for them to adjust their (highly leveraged) positions if their predictions were wrong without causing havoc.
Their models were in some sense correct, but they couldn't be put into practical use because of the "everyone runs for the exit at the same time" problem when the model switched from "green light" to "red light".
Stock price is related to expected future earnings (discounted by a suitable interest rate) only indirectly: through expected dividends, and also through the net value of the company as a whole given the possibility of future acquisition.
There's already wiggle room dependent on the time frame in which dividends will actually be paid out (despite the M&M theorem), and in the interest rate you use, but the key issue is EXPECTED.
EXPECTED earnings depend strongly on the current state of "animal spirits" in stock traders, as well as actual events.
The feedback loop of a bull market also can have a strong effect: the rising price indicates someone expects future earnings to be strong, so it causes others to revise their expectations upward, bidding up the price. A bear market has a similar feedback mechanism: falling prices indicate someone believes future earnings to be weak, causing others to revise their expectations downward.
When technical "analysts" can still find an outlet for their voodoo "support level" nonsense, you know the stock market isn't based on a rational evaluation of earnings.
Sure, and maybe we'll have robots with positronic brains by 1985. Oops. You are talking about science fiction. Putting "superstring" and "brane" or "black hole" in your post is not the same as making a scientific argument.
There are many possibilities outside the realm of current physics theories. It's trivially easy to come up with some, as you have. The problem is not to come up with ideas beyond current physics, it is to come up with ideas which are WITHIN this tricky thing called REALITY. And modern physics does a damn good job of describing reality already. Improving it is hard work.
Might as well hope that future scientific discoveries allow "chocolate cake for everyone! Yay!"
Funny, the "right" to watch a baseball game or movie in person is something I buy at the box office. No ticket, no admission; that's not a violation of my Constitutional rights, is it? The right to use equipment at my gym is another thing I buy. The right to eat a cheeseburger from McDonalds is another thing I have to buy on the market.
When a "right" is the "right to make use private property" it *is* something that can be bought in the market. And it so happens that in this reality, musical works and performances are (intellectual) property, for which the right of re-distribution is restricted to those licensed by the copyright owner, except under the *limited* free use exceptions.
I can't find any that are exactly 1600x1200. When I chose a 8600, and configured it like the low-end 15-inch (Combo drive only, 256 MB ram, 64 MB VRAM, 60 GB hard drive, 1.5 GHz Pentium M, PLUS remembered to add 802.11b/g built-in), I got a price of $1422. Compared to the $2000 for the Powerbook.
That's $578, not $1000, AND, I still didn't get Gigabit Ethernet, a Pro version of the OS, or Firewire 800, and the external video port isn't digital. And it weighs a pound more (6.9 vs. the 5.7 lb powerbook).
We may not have reached the end of physics, but if you are relying on the claim that "undiscovered physics will allow transistors made smaller/faster than current physics permits" you aren't making a very persuasive argument.
Are you expecting atoms to be made smaller? Are you expecting light to go faster? Hoping won't make it so.
Or are you suggesting all the evidence for quantum and relativistic limits to be simply "not thinking hard enough"? If so, you have an insultingly low opinion of the physics community.
Slashdot Mirror
we are always feeling the force of gravity, right?
It depends very much on what you mean by "feel" gravity.
On the surface of the earth, the way I use the word "feel", I "feel" the pressure in my legs when I am standing up, and I "feel" the pressure in my butt when I sit down. It "feels" exactly like the floor or seat is pushing me up.
Now, in my usual frame of reference (fixed to the floor), I am not accelerating. But Newton says "F=ma" and I feel a force acting from the floor. How can that be, says the physics student? Well, says the physics guru, there must be *another* mysterious force acting on you to balance out that force that you feel from the floor. I will call that force "gravity". You can measure the magnitude of the force by putting a thing called a "scale" between your feet and the floor, and it will measure the force the floor exerts on the scale, and that the scale exerts on you, (because, after all, the scale isn't accelerating, either, when you use it properly).
The important thing to know is that YOU ARE NOT MEASURING THE GRAVITATIONAL FIELD! What you can measure is the force exerted on the scale, OR, throw something in the air and measure its ACCELERATION in your frame of reference. The only way you can link this to something called "gravity" is to have a *theory* of gravity.
The only way (known to current physics) you could really measure the gravitational field (actually, the curvature of space-time) directly is some very sensitive measurement, for instance, to use optical means to detect curvature of space; in practice, this only works for looking for bright, distant objects behind big things like planets, stars, galaxies, etc. You can also use a big metal resonator to pick up minute vibrations caused by things like stellar explosions. It is no coincidence that these experiments, done by physicists, all are testing something they call the GENERAL THEORY OF RELATIVITY.
This slashdot discussion is a perfect example of "a little knowledge is a dangerous thing." You people all *think* you paid good attention in your Physics 101 class, or whatever, but you didn't really think very hard about what you supposedly learned.
Now, you may have some magic ESP-like power that lets you feel the gravitational field, but I'm guessing not.
Zero-g doesn't exist anywhere in our universe
How do you know? Imagine an experimental method for determining that a region of space has zero gravitational field (or zero space-time curvature, if you like). How would that method distinguish the zero curvature from free-fall?
Note, in particular, the problem of establishing a "fixed" frame of reference in space-time. Perhaps that is what Einstein was talking about when he called his theory "General RELATIVITY."
You flakes are all getting worked up into a lather about something that is nowhere near as clear-cut as you make it out to be, and a careful consideration of the facts should make that clear to you, if you spent as much effort on asking yourself difficult questions as you do lambasting others.
Note also that it is by no means obvious, for instance, that "looking out the window" of the spacecraft and seeing a planet rotating "below" you means that you are in orbit around the planet. It is only clear if you know that the thing out the window has MASS. How do you really know it has mass? Through gravity? Well, that's a circular argument, isn't it?
In fact, it is easy to imagine that you *could* set up masses around you to cancel out the gravitational fields of every other object. Putting yourself *inside* a massive spherical shell would be a good start. Then, add small lumps to the spherical shell to cancel out the residual effects of far-away bodies.
Einstein's Theory of *General* Relativity includes the Principle of Equivalence, namely,
There is no physical way of distinguishing between a UNIFORM gravitational field from a UNIFORM linear acceleration.
Since there is no way to distinguish between the gravitational field being uniformly *zero* and a uniform acceleration of *zero*, there is no distinguishable difference between your "Zero G Force" (F=ma ---> F=0 a = 0) and "Zero Gravity" (F = 0 because Gmm/r^2 = 0).
Now, the nit to pick that leads to the term "microgravity" is that the gravitational field in Earth orbit is not uniform over a finite region; there are (minute) tidal effects, anisotropies, spacecraft vibration, drag at low earth orbit, etc., all of which are, in principle, detectable, and some of which could not be produced except by a non-uniform gravitational field, although determining that might be beyond a particular experimental error.
Note, in passing, that NASA uses the "Zero Gravity" term to describe it's Earth-based drop facilities.
If you find a 100 years old film sitting in an attic you'll be able to watch it pretty easily
Actually, if you find a 100 year old motion picture, the film base was probably celluose nitrate. After 100 years, there is a very good chance you'll have nothing left but a dark brown, extremely flammable, acidic powder. Even if you have film, it is extremely hazardous and fragile. Hardly "easy."
Even for film that is only 60 years old, it is likely to be on acetate base, which degrades into acetic acid (vinegar), which doesn't provide much support for the emulsion.
Which doesn't even touch the topic of the degradation of color dyes in color film.
No body is trying to take away your little "brother." Maybe he just doesn't want to come live with you. He moved away a *long* time ago, and likes his own home. If he stays away until 2020, you plan to hunt him down?
Again, what gain is there for the people of Taiwan? NONE. The only reason you give is basically to save face for the mainland rulers. If you had non-violent reasons that the Taiwanese would find persuasive, the PRC wouldn't have to keep the military threat alive and install more and more missiles on the mainland which threaten Taiwan.
If you are so big on "trust", why don't you "trust" the people in Taiwan to decide what is right for themselves without bringing military threats into it?
Taiwan has been taking care of itself for the last fifty years and did a hell of a lot better than the Communist party has done with their chance to govern the mainland. They even have this miraculous thing called democracy with truly free, fair, and open elections. In the meantime, every mainland leader talks about "democracy in 50 years" meaning "democracy sometime after I am dead."
Instead, you follow the typical mainlander line of: "we should be husband and wife, so marry me or I'll kill you." No benefits for the Taiwanese mentioned at all. Who would want to take an offer like that?
So you're saying the interface seems snappier?
Twentieth-century physics also gave us the solid state (quantum mechanical) theories needed to understand semiconductor rectification and other phenomena used to make things like, oh, TRANSISTORS. And the atomic physics necessary to make LASERS. So that computer with its CD-ROM drive in front of you wouldn't exist without the efforts of 20th century PHYSICISTS.
None of these were "technologists" working on something they didn't understand, but scientists who actually used the full power of modern physical theories to predict and discover useful phenomena.
And I haven't even reached back to the 19th century to mention a guy by the name of Maxwell, and all the great things made possible by his theoretical research. Like, oh, I don't know, radio.
Even Edison wouldn't have gotten very far if it hadn't been for Ampere, Coulomb, and Faraday. All that funky telegraph stuff that gave Edison his start depended on what was once cutting-edge physics.
I'll freely admit general relativity hasn't (and almost certainly won't) lead to technological breakthroughs. But quantum mechanics has pretty clearly kicked ass.
Most languages which have tail-call elimination ALSO have implementations which put effort into making function calls efficient. Basically, the call is reduced to the same jump that your for-loop solution has anyway.
Whether recursion is "natural" or not depends on the PROBLEM, not the language. Recursion is a natural solution to mapping over a binary tree, for instance. It is the most straightforward solution for factorial and the Fibonacci sequence. You might argue that calculating the Nth member of the Fibonacci sequence is not naturally recursive, although the usual definition of the *sequence* is, because of the extreme redundancy of the computation. (Actually, the Fibonacci sequence is the best example of a recursive solution that is unnaturally inefficient; that's why everyone uses the same example.)
The ability to express a solution in the natural way, of course, does depend strongly on the language.
Code reviews and debugging tools can be used for any language.
The difference is that code reviews, and management resources in general, for more powerful languages can focus more on high-level issues that make a difference, and automated tools can be used for useful end goals such as improving run-time performance and adding features.
While the C++ guys are still crawling around in the dirt playing a game of "who dropped the pointer."
In my experience, the most annoying things are all the electronics-type stuff (EEPROM burners, etc.) that were meant to hang off a parallel port. Vendors typically only provide Windows support, but sometimes a Linux hacker has made an equivalent too, but still using the parallel port hardware.
I keep looking around for something that gives me a USB/Firewire interface to a box which has a bi-directional parallel port, so at least I could adapt all the hacked-up x86 linux clone software on a Mac. But I can never find one.
Anyone have a hint?
Oh, and forgot
4) Run your crucial apps a minimum of 4--5 times SLOWER in emulation than a native PC, so that your engineers can waste their precious time (at minimum $50/hour each) waiting for screen refreshes, in order to save you the $500 Windows license.
I'm not sure that these are good examples.
Core engineering applications are
1) Vital to the success of the products you are engineering
2) Usually the worst citizens in the Windows world, so they are the hardest to emulate.
3) Dwarf Windows in cost.
Who in their right mind is going to run a critical engineering app in an emulator?
1) Run into any issue, call up the CAD vendor and have them say "we don't support running it on anything but real 100% windows....click, dial tone,..."
2) Make critical engineering work depend on the least-used portions of the emulator, written by random open-source jockey, and only lightly tested by the thousands of teenage users who mainly use it to run video games.
3) Save the cost of a $500 Windows license, while still spending $30,000 on a CAD license, and $100+k/year on the engineer. Penny wise, pound utterly stupid.
The most commonly mentioned difficulty is the number of registers in PPC vs. x86. RISC instruction set architectures like PPC tend to have a relatively large number of general purpose registers, vs CISC ISA's which have a smaller number of registers, some of which have special purposes. (CX for count, SI, DI for offset indices, ..., my x86 knowledge is VERY stale, so I'll be vague from here on)
..., r17..r32 available) The CISC ISA emulating the RISC will tend to
In emulation, to keep things fast, you would like to dedicate one hardware register for each emulated register, plus you need hardware registers to actually run the emulator!
A RISC ISA emulating a CISC ISA will enough registers to do so. (r1 = AX, r2 = BX,
1) need to use the most flexible registers (AX) to run the emulator (e.g. load the RISC opcode from RAM into AX, extract the opcode field, compare it to your opcode table, and dispatch, because AX has the best support for bit operations, let's say)
2) also use the special-purpose registers to run the emulator (e.g. use an index register to index into your opcode tables)
3) leaving too few registers to hold all the emulated registers (oops, we only got r1..r3 in the left over registers; what about r4..r32...)
4) having to use "weak" or wrongly-specialized registers to hold the key RISC registers which are heavily used in the actual RISC program. (E.g., your program is trying to number crunch so it wants to do a lot of floating-point math on data which is being stored in some left-over CISC register which doesn't support floating point natively.)
[note, I'm well aware that x86 is not a CISC hardware implementation under the hood, but to the assembly programmer, it presents a CISC instruction set architecture. Emulating the underlying microcode RISC engine, however, would likely need even more registers, causing the same problems, so you would tend to emulate the CISC model.]
Or, you could recognize all belief is tenative. That as much objective evidence exists for the divinity of the Buddha, for instance, as exists for the divinity of Christ. That just as the truth of Christian scriptures is vehemently believed by Christians, the truth of the Koran is vehemently believed by Muslims.
Which is to say that a truly thoughtful person with religious beliefs ought to be able to empathize with the religious beliefs of others, although they might be quite different.
Although I am a Christian in upbringing, if a Jew tells me his faith requires me to cover my head when I enter a synagogue or attend a Jewish wedding, or for him to abstain from a cheeseburger, I respect that belief, just as I would expect him to respect the doctrine of transubstantiation if I explain it to him. I don't expect him to *believe* in it, but I would expect him to *respect* it.
Unfortunately, there are few truly thoughtful people in the world.
Instead, we get thoughtless people who can simultaneously push to re-introduce prayer into American schools, while decrying the madrassahs of the Mideast for teaching hate and intolerance.
Gosling is not discussing the details of widgets, etc., which make up the (hopefully consistent) USER EXPERIENCE of a graphical user interface; instead, he's concerned with the low-level plumbing which lets multiple applications share the screen and mouse, without having to be aware that other applications have windows which might be overlapping one's own. These problems are totally different, and mostly unrelated.
The widgets that make up the GUI of each application, as well as the lowest-common-denominator graphics tasks could be provided by a single system-wide library that every application would use, to ensure consistency. Gosling is only thinking about how this library would send colored bits to the screen and get mouse clicks from the user.
Quartz doesn't enforce a single user interface, as Apple's own "interface of the year" adventures demonstrate.
Garbage collection means you don't have to use tools that run your program in a sandbox to avoid programming errors which are unfortunately easy to make. Instead, you can spend the time making enhancements and improving performance instead of plugging stupid leaks all day.
Valgrind only fixes memory allocation problems which you can reproduce in a test situation. It doesn't fix memory allocation problems which occur when your application reaches the field and can be subjected to long runs with unpredictable inputs.
Garbage collection IS a modern programming tool. Why are you so afraid of it?
If Apple sold its wares at CostCo, any $500 iMac would sit right next to a $399 Windows machine.
If anyone *did* buy it because daughter Missy thought it was "cuter", they'd bring it home and wonder why why they didn't get the blue-sky-and-clouds when they boot up and why all their pirated software from work wouldn't install on this machine.
The mass market doesn't understand Windows != computer.
Except, if you make the same mistake with a monetary value card, you're out the $1.50 (or is it up to $2 now?) instead of just 18 minutes of your time.
Actually, it was Russia.
Also, the real problem LTCM had was that a lot of the opportunities that they were trying to exploit involved markets that were rather small and illiquid. Meaning it was impossible for them to adjust their (highly leveraged) positions if their predictions were wrong without causing havoc.
Their models were in some sense correct, but they couldn't be put into practical use because of the "everyone runs for the exit at the same time" problem when the model switched from "green light" to "red light".
Stock price is related to expected future earnings (discounted by a suitable interest rate) only indirectly: through expected dividends, and also through the net value of the company as a whole given the possibility of future acquisition.
There's already wiggle room dependent on the time frame in which dividends will actually be paid out (despite the M&M theorem), and in the interest rate you use, but the key issue is EXPECTED.
EXPECTED earnings depend strongly on the current state of "animal spirits" in stock traders, as well as actual events.
The feedback loop of a bull market also can have a strong effect: the rising price indicates someone expects future earnings to be strong, so it causes others to revise their expectations upward, bidding up the price. A bear market has a similar feedback mechanism: falling prices indicate someone believes future earnings to be weak, causing others to revise their expectations downward.
When technical "analysts" can still find an outlet for their voodoo "support level" nonsense, you know the stock market isn't based on a rational evaluation of earnings.
Sure, and maybe we'll have robots with positronic brains by 1985. Oops. You are talking about science fiction. Putting "superstring" and "brane" or "black hole" in your post is not the same as making a scientific argument.
There are many possibilities outside the realm of current physics theories. It's trivially easy to come up with some, as you have. The problem is not to come up with ideas beyond current physics, it is to come up with ideas which are WITHIN this tricky thing called REALITY. And modern physics does a damn good job of describing reality already. Improving it is hard work.
Might as well hope that future scientific discoveries allow "chocolate cake for everyone! Yay!"
Funny, the "right" to watch a baseball game or movie in person is something I buy at the box office. No ticket, no admission; that's not a violation of my Constitutional rights, is it? The right to use equipment at my gym is another thing I buy. The right to eat a cheeseburger from McDonalds is another thing I have to buy on the market.
When a "right" is the "right to make use private property" it *is* something that can be bought in the market. And it so happens that in this reality, musical works and performances are (intellectual) property, for which the right of re-distribution is restricted to those licensed by the copyright owner, except under the *limited* free use exceptions.
Which Inspiron do you mean?
I can't find any that are exactly 1600x1200. When I chose a 8600, and configured it like the low-end 15-inch (Combo drive only, 256 MB ram, 64 MB VRAM, 60 GB hard drive, 1.5 GHz Pentium M, PLUS remembered to add 802.11b/g built-in), I got a price of $1422. Compared to the $2000 for the Powerbook.
That's $578, not $1000, AND, I still didn't get Gigabit Ethernet, a Pro version of the OS, or Firewire 800, and the external video port isn't digital. And it weighs a pound more (6.9 vs. the 5.7 lb powerbook).
We may not have reached the end of physics, but if you are relying on the claim that "undiscovered physics will allow transistors made smaller/faster than current physics permits" you aren't making a very persuasive argument.
Are you expecting atoms to be made smaller? Are you expecting light to go faster? Hoping won't make it so.
Or are you suggesting all the evidence for quantum and relativistic limits to be simply "not thinking hard enough"? If so, you have an insultingly low opinion of the physics community.