Nope, the universe would seem to be 2D if it was 3D, but the universe is actually 4D, so it looks to us to be 3D.
"If the distance of everything from the big bang was equal, someone would've noticed and found that point using simple trigonometry by now"
The distance to the big bang is measured in time, and you can get a rough idea of where it would be, as that's what the estimated age of the universe is; the distance to the big bang. The distance in space is measured as zero, ie, nothing has moved further away from where the big bang happened, only further away from other things within the universe. Again, go with the expanding balloon idea, with the distance from the surface to the center being time, and the two dimensions of the surface being space (ignoring one of the space dimensions to do this). All points on the surface are the same distance from the center (the same age), moving further from each other, but are still on the same bit of rubber that they were when the balloon was totally deflated (they haven't moved away from the rubber).
The surface of a balloon is only 2D. What makes the "everywhere is middle" argument here is not the number of dimensions, but the loop property of it (if you keep going, you end up where you started). Thus we can only say "everywhere is the middle" for our universe if we assume the universe shares that property. Otherwise, the universe could go on forever, in which case there's no middle (only a middle to the observable universe, which is wherever you are observing from), or has an edges which the middle can be defined from.
Of course a looped universe doesn't necessarily imply we could keep travelling and get back here, due to expansion; the distance from one point, all the way round back to itself, expands faster than we could travel.
Without agreeing on the shape of the universe, it makes no sense really to talk about absolute coordinates. The only "edge" that has shown to exist so far is an edge of time at time zero.
(this is my intuition speaking here... it seems right, but I know how much trouble that can get you into when talking about things like the shape of the universe!)
"If you construct a car that lacks brakes it's a disaster"
That's not really what we're talking about here though is it. If there's some force that we haven't spotted here in earth, but comes into play when large galaxies are observed, then until we start trying to build large galaxies, it's not exactly a huge worry. It doesn't affect our cars, our planes, our coal stations; our inventions do work. At some point our technology may progress to the point where we need more accurate information about what's going on our there, eg when it comes to intersteller travel, but that doesn't invalidate anything we've done so far or are doing so far, just as newtonian physics is enough for most current inventions as figures only start going off when relativistic speeds are reached, which isn't a common day occurance.
cool! Anyone who wants to try it, it's IPv1 address is 12. You can download an IPv1-in-IPv4 tunnel from sourceforge. Please note, it doesn't support ICMP-echo-request (not having enough memory to receive an ICMP packet), it only supports 12.
So... what you're saying is we need to invest the required huge amounts of money and effort into an inspiration-speech AI? Then we'll be able to justify to the people the money and effort required to send out loads of probes?
"( >90% of the universe are dark matter and dark energy)"
"Could be", it's a bit early to say with that kind of certainty (as you know by your previous sentence). There could [likely?] also be some unknown force at play, something that changes the way time's perceived (thus things look to be moving faster/slower than they are, throwing off mass estimations), a property of matter that changes how much it interacts with/produces gravity. How many constants in the equations we use are really constants, and how many are maybe functions of the length of time since the big bang, that we're not yet aware are changing?
Our current model I wouldn't say it "way off", just only a [small] part of the overall picture.
Actually everything already is travelling at the same speed, but in a 4 dimensional space. What we see as "speeding up" and "slowing down" is actually just a change in direction. Travelling at the speed of light means you're moving at a right angle to the time dimension. You can't increase this angle further than 90degrees, it just becomes 89degrees again, measured from the other side (ie, you're travelling backwards in time, getting younger, and moving backwards... which is indistinguishable from travelling fowards in time, getting older, and moving forwards). So, travelling above and below the speed of light inflicts the exact same consequences onto the rest of the universe, which is why saying "travelling faster than the speed of light" is such a redundant thing to say.
My guess is that the ASID space may only be small (eg, a single byte); big enough to give each virtual machine its ID, but not big enough to give each process its own... what you'd need is some simple heuristics to work out which processes are running most often, and give them their own ASID, and all others would have to share and flush the TLB between switches between them. I guess if you gave processors which support this tagged TLB to kernel developers, we might see it come into mainline, otherwise people don't feel it's worth it? *shrug*
I think it's along the lines that mass appears to pull things through time; objects with mass age. When energy loses its mass, it no longer ages, and is therefore travelling at speed C (to the energy, it travels instantaniously, to everything else, it will pass at the speed of light). This is what happens when you eg, charge a particle so that a photon is given off. If that photon gains mass (eg, is absorbed into matter, warming it slightly) it will be pulled through time, will begin to age, therefore will be travelling through less space per time, which is under the speed of light.
The real twist here is that for an object to be accellerated past the speed of light, that object would actually 'see' the rest of the universe travelling backwards, and would arrive at its destination younger than it was when it left... so it'd simple appear to us as if the packet had travelling from the 'destination' to the 'source', at a speed below the speed of light... objects travelling faster than the speed of light, and objects travelling below it, appear indistinguishable to us.
Xen has implemented use of tagged TLBs to save TLB flushing between switching virtual machines. The technology (on x86) is reaching (or has reached) two years old now, so there may well be other users of it by now.
"There is nothing special about java or net that would allow this optimization"
Sure there are. A profiler could quickly pick up on a function that's getting called many times from within a loop, and decide it could speed it up more by inlining it. Or, a bit of inline code that isn't being used often could be moved out of line, so the rest of the loop fits into a single cache line.
Profiling is useful for code produced by any language, and being able to profile without adding code, eg, at the beginning of functions, means you get to see how the actual software runs, without doing things that affects caching etc (for example, profiling code might push certain instructions onto a different cache line, skewing the results)
Aside from what others mentioned, "3D-Now!" was added by AMD on the K6/2, as a kind of floating point MMX type thing I seem to recall. Intel later incorporated* these instruction sets, and AMD incorporated* Intels SSE instruction sets.
Slashdot Mirror
"Also the universe as we see it would be 2D"
Nope, the universe would seem to be 2D if it was 3D, but the universe is actually 4D, so it looks to us to be 3D.
"If the distance of everything from the big bang was equal, someone would've noticed and found that point using simple trigonometry by now"
The distance to the big bang is measured in time, and you can get a rough idea of where it would be, as that's what the estimated age of the universe is; the distance to the big bang. The distance in space is measured as zero, ie, nothing has moved further away from where the big bang happened, only further away from other things within the universe. Again, go with the expanding balloon idea, with the distance from the surface to the center being time, and the two dimensions of the surface being space (ignoring one of the space dimensions to do this). All points on the surface are the same distance from the center (the same age), moving further from each other, but are still on the same bit of rubber that they were when the balloon was totally deflated (they haven't moved away from the rubber).
Hope this helps.
The surface of a balloon is only 2D. What makes the "everywhere is middle" argument here is not the number of dimensions, but the loop property of it (if you keep going, you end up where you started). Thus we can only say "everywhere is the middle" for our universe if we assume the universe shares that property. Otherwise, the universe could go on forever, in which case there's no middle (only a middle to the observable universe, which is wherever you are observing from), or has an edges which the middle can be defined from.
Of course a looped universe doesn't necessarily imply we could keep travelling and get back here, due to expansion; the distance from one point, all the way round back to itself, expands faster than we could travel.
Without agreeing on the shape of the universe, it makes no sense really to talk about absolute coordinates. The only "edge" that has shown to exist so far is an edge of time at time zero.
(this is my intuition speaking here... it seems right, but I know how much trouble that can get you into when talking about things like the shape of the universe!)
Relatively speaking, the universe could be a constant size and everything in it getting smaller :-)
*lol* excellent
hehe, i like the way you get to tell a joke and seem disapproving of it at the same time.
...and I'm a little bit rock 'n roll ya!
Cuz I'm a little bit country...
"If you construct a car that lacks brakes it's a disaster"
That's not really what we're talking about here though is it. If there's some force that we haven't spotted here in earth, but comes into play when large galaxies are observed, then until we start trying to build large galaxies, it's not exactly a huge worry. It doesn't affect our cars, our planes, our coal stations; our inventions do work. At some point our technology may progress to the point where we need more accurate information about what's going on our there, eg when it comes to intersteller travel, but that doesn't invalidate anything we've done so far or are doing so far, just as newtonian physics is enough for most current inventions as figures only start going off when relativistic speeds are reached, which isn't a common day occurance.
"Computers increased the number of things humans could do without thinking"
:-)
And of course, the number of mistakes per second that can be made
cool! Anyone who wants to try it, it's IPv1 address is 12. You can download an IPv1-in-IPv4 tunnel from sourceforge. Please note, it doesn't support ICMP-echo-request (not having enough memory to receive an ICMP packet), it only supports 12.
"But how does VI&II plan on getting past that pile of space crap called the Oort cloud?"
That very question was asked in a recent interiew. After a long delay, the V1 probe responded: 10.4082.... 10.4083.... 10.4084...
Doesn't sound like much, but is the best plan it could come up with. V2, however, is equipped with a pole vault.
and to occupy rocket engineers who otherwise could've ended up working for (in some way or form) the enemy or an enemy-to-be.
"Currently I do not see the need to hope and pray every time that old crate takes off, whether those 7 people on board will make it"
;-)
Neither do I, there's plenty more astronauts where they come from
So... what you're saying is we need to invest the required huge amounts of money and effort into an inspiration-speech AI? Then we'll be able to justify to the people the money and effort required to send out loads of probes?
It's so crazy it might just work...
But that would remove your post too!
"( >90% of the universe are dark matter and dark energy)"
"Could be", it's a bit early to say with that kind of certainty (as you know by your previous sentence). There could [likely?] also be some unknown force at play, something that changes the way time's perceived (thus things look to be moving faster/slower than they are, throwing off mass estimations), a property of matter that changes how much it interacts with/produces gravity. How many constants in the equations we use are really constants, and how many are maybe functions of the length of time since the big bang, that we're not yet aware are changing?
Our current model I wouldn't say it "way off", just only a [small] part of the overall picture.
"but can't you tell if it HAS collapsed into a state?"
Only by 'observing' it, which would force it to happen anyway.
That's all assuming you can introduce tachyons.
Actually everything already is travelling at the same speed, but in a 4 dimensional space. What we see as "speeding up" and "slowing down" is actually just a change in direction. Travelling at the speed of light means you're moving at a right angle to the time dimension. You can't increase this angle further than 90degrees, it just becomes 89degrees again, measured from the other side (ie, you're travelling backwards in time, getting younger, and moving backwards... which is indistinguishable from travelling fowards in time, getting older, and moving forwards). So, travelling above and below the speed of light inflicts the exact same consequences onto the rest of the universe, which is why saying "travelling faster than the speed of light" is such a redundant thing to say.
My guess is that the ASID space may only be small (eg, a single byte); big enough to give each virtual machine its ID, but not big enough to give each process its own... what you'd need is some simple heuristics to work out which processes are running most often, and give them their own ASID, and all others would have to share and flush the TLB between switches between them. I guess if you gave processors which support this tagged TLB to kernel developers, we might see it come into mainline, otherwise people don't feel it's worth it? *shrug*
I think it's along the lines that mass appears to pull things through time; objects with mass age. When energy loses its mass, it no longer ages, and is therefore travelling at speed C (to the energy, it travels instantaniously, to everything else, it will pass at the speed of light). This is what happens when you eg, charge a particle so that a photon is given off. If that photon gains mass (eg, is absorbed into matter, warming it slightly) it will be pulled through time, will begin to age, therefore will be travelling through less space per time, which is under the speed of light.
:-p)
The real twist here is that for an object to be accellerated past the speed of light, that object would actually 'see' the rest of the universe travelling backwards, and would arrive at its destination younger than it was when it left... so it'd simple appear to us as if the packet had travelling from the 'destination' to the 'source', at a speed below the speed of light... objects travelling faster than the speed of light, and objects travelling below it, appear indistinguishable to us.
(or something like that
Xen has implemented use of tagged TLBs to save TLB flushing between switching virtual machines. The technology (on x86) is reaching (or has reached) two years old now, so there may well be other users of it by now.
"AC gets no real attention from anyone, especially me"
You do a great 'not-giving-attention'.
"x86 does not have a tagged TLB"
/ 05/15/1750200 , search on page for 'tagged')
Traditionally, no, but newer processors have introduced it, eg, along with virtualisation extensions (found one reference here: http://amd.vendors.slashdot.org/article.pl?sid=06
"There is nothing special about java or net that would allow this optimization"
Sure there are. A profiler could quickly pick up on a function that's getting called many times from within a loop, and decide it could speed it up more by inlining it. Or, a bit of inline code that isn't being used often could be moved out of line, so the rest of the loop fits into a single cache line.
Profiling is useful for code produced by any language, and being able to profile without adding code, eg, at the beginning of functions, means you get to see how the actual software runs, without doing things that affects caching etc (for example, profiling code might push certain instructions onto a different cache line, skewing the results)
Aside from what others mentioned, "3D-Now!" was added by AMD on the K6/2, as a kind of floating point MMX type thing I seem to recall. Intel later incorporated* these instruction sets, and AMD incorporated* Intels SSE instruction sets.
(*mostly)