Because the galaxy is not a point mass. Most ordinary star/planet modelling is based on viewing each object as a sphere, which behaves as a point mass at the centre. But when you penetrate inside another body, as two galaxies do when they collide, this simplification no longer applies. Some of the mass of the "other" galaxy moves behind the penetrating galaxy, slowing it down rather than, as the point mass model would suggest, continuing to accelerate into the centre. In the simplest model, of inter-penetrating spheres, gravity no longer has an inverse square law but an inverse linear law. Of course, galaxies are not uniform spheres, and the modelling is much harder. However, it is widely accepted that when two galaxies collide, they merge and the vast majority of the mass forms a single galaxy - though clusters may be flung out. If the galaxies are of broadly similar masses, the distinctive spiral structure is wiped out and the merged result becomes an elliptical galaxy for a few hundred million years before the spiral structure re-establishes.
Google "andromeda collisions" for simulations of the collision between our galaxy and the Andromeda galaxy in about 3 billion years.
Many kinds of animals survived, after all. Why shouldn't dinosaurs have, too?
Basically, size. The dinosaurs were all largeish - turkey-sized or bigger - with the exception of thos who seem to have evolved into birds, and may have been much smaller because of the nifty invention of feathers. The only mammals at the time were small, shrew-like animals. It is not unreasonable to think that small beasts could survive, scavenging of the dead big beasts, where big beasts could not.
The possibilities for hacking other people's tattoos are frightening. You can hardly go around keeping a continuous watch on them, especially on your back. Imagine going to work at school labelled "Crack $5/bag".
What I like about this is not so much the potentially faster upgrade as the ability to contribute a bit to others. The six-monthly upgrades are are rate enough that I don't mind if they are a bit slow - not that they have been. But I am very conscious that I am using other people's freely given bandwidth and I am pleased to be able to give some back.
Does anybody know if I can force my various machines to cross-peer from each other? If I update one first, I don't want the others searching the Net for peers - they should just copy from the first.
One word I would like to see get more use is "Sophont", coined by Poul Anderson (actually by his wife, I believe, but his name is on the books) to mean any life intelligent enough to share what we currently call "human rights" but will have to stretch when we meet intelligent ETs.
You have a very mediaeval understanding of the word "King". Sure, that is the way they used to be. But democracy has, quite correctly, slid all the power over to elected institutions. Walter Bagehot wrote an influential book on the British Constitution in which he distinguished the Efficient from the Dignified parts of government. The Efficient part does the work, but every country needs a Dignified pare. This includes flags, soldiers in archaic uniforms, lots of saluting, bugle calls and running around. Constitutional monarchies have left the monarch as entirely part of the Dignified part of government, representing the country without having to do anything much. This leaves everybody free to criticize the politicians without attacking their symbolic head.
It is, in my opinion, a (minor) defect of the US constitution that the President is the head of both Efficient and Dignified sides of the government. This means that he has to waste time with, for example, pinning on medals. And on the other side, those receiving medals may not be best pleased to get them from a politician they may abhor.
The concept of a King never was what the fairy tales imagined, and has moved on a long way since the King was a position of power. It is now purely a symbolic position.
Constitutional monarchs are figureheads - as responsible for the laws passed by the parliaments of their countries as the flag is. In the UK at least, the Queen reigns but does not rule: her role is entirely ceremonial (well, almost: in certain very obscure circumstances she can be a tie breaker). Monarchies today are not what they were in the thirteenth century.
I don't think that any of this is the King's doing. It is the major parties which have made hyper-loyalty to the King a kind of shibboleth. A bit like the McCarthy era in the US, when it almost became UnAmerican to admit to having a left hand. You protest your loyalty to the King loud and long to prove your patriotism, then when anybody accuses you of thinks like taking bribes, you call them unpatriotic. So there is a huge "more respectful than thou" campaign going on - but none of it supported in any way by the King himself.
When s/he says that "people thought", GP I hope means that some people thought, not that all people thought. People like Dr Dionysius Lardner http://en.wikipedia.org/wiki/Dionysius_Lardner, self-appointed pundit and critic of Brunel. Such people still exist, and get credibility amongst those without scientific or engineering training. Selective reporting and mindless extrapolation will always generate a result sensational enough to get some headlines for those in search of such.
Which is why I classified astronomy, of which astrophysics is a part, as an observational science in the very next sentence. Much of biology is also observational, but increasing amounts are becoming experimental, for example as people are able to construct small scale repeatable ecosystems.
I was very explicitly trying to make the point that not all science is experimental. Collecting a large number of observations of equivalent objects is also science. But observational science requires a large number of essentially equivalent observations: watch a planet for years, observe tens of thousands of stars, collect tens of thousands of fossils, observe strata at hundreds of locations. Economics cannot do that: there is only one world economy, and national and local economies are too different to get comparable observations.
Which just shows that economics and finance are not, in any sense we generally recognise, sciences. Just using mathematics and graphs does not make something a science. Economics obviously does not meet the criteria of an experimental science like physics or chemistry: you cannot perform repeatable experiments. Nor does it meet the criteria of an observational science like astronomy or palaeontology: huge numbers of essentially comparable observations (take millions of star photos, collect rooms full of fossils).
Aside from these problems, economics suffers from insufficient isolation: the elements being measured react not only to the measurement but to the theories being made about the measurements.
Therefore it is not reasonable to relate any problems in the economy and financial markets to the body of knowledge we generally call science.
But that is based on the assumption that the CMB is, indeed, the relic of the Big Bang, which is one of the assumptions referenced. And that the Hubble shift is, indeed, caused by the expansion of the Universe. Of course, I do not really doubt this, but these are still very indirect deductions. One could imagine a measurement which cast doubt on all of them - e.g. speed of light changing with time, in which case the whole Universe would probably need to be rescaled.
If firmly mounted, the drives are very shock tolerant. What people don't realize is how high the G force generated when hard object like a drive hits a hard object like a table. You can get instantaneous tens, possibly hundreds of Gs. Earthquakes can generate several Gs, but not tens. Problems tend to occur when structures have forces in unexpected directions (walls are bad at shifting sideways, masonry doesn't like decompression) or when you get resonance with the oscillation, which builds up the energy. Disk drives don't have these failure modes.
But how does one answer "The question is not meaningful because I do not accept the existence of evil spirits". You could say that this implies and answer No, but it seems to me that am meaningless question does not deserve even a default answer: GIGO applies: if the input is garbage, anything derived from it is garbage, even if it appears to have meaning.
Fine. Now how do you expect a dumb processor to do what a clever programmer cannot? If we knew how to build machines that could do this, we would have done it. But to allow for parallelism, you have to understand the why of the system, not the what. And that gets lost between design and code.
*Not* minicab drivers. The ones who have to take The Knowledge are the licensed cab drivers of London, who usually drive the famous Black Cabs (nowadays not always black), and are allowed to pick up passengers who hail them on the street. Minicab drivers is the term used exactly for those those who are *not* licensed drivers who have done The Knowledge. You have to book them (e.g. by phone) and there are far fewer controls over them. And all this applies only in London.
Having worked in the industry, they are already transitioning to 10bits/sample, and may go to 12, but I really don't expect them to go to 16. And the standard "4k" size is 4k x 3k. Bot of those shrink your numbers a bit. And they haven't really developed the compression for stereo, which ought to be extremely efficient because the two images are nearly identical.
I have a Facebook account created when someone asked me to look at their pages. I haven't logged in in certainly one, maybe two, possibly three years. I would never see anything serve on me there.
I probably have accounts on a score or more other forums and so on that I signed up to, used for a short while, and either got bored or achieved what I needed. Do I have to keep monitoring all of these in case someone chooses to post an important message?
The article does not state whether the court required the plaintiff to show that the defendant was currently active on Facebook, or even that the question was asked. That strikes me as an important point. If you could show that the defendant regularly used their Facebook account both before/and after/ the attempted service, the reliability of the claimed service becomes much greater.
I think, and hope, that it is more a case of the downturn jolting a lot of people out of their ruts. However much you may think or even know that *nix is better than Windows, it is a big decision to change a company from one to the other. In good times, you can afford the Windows tax, and pay it just to avoid the hassle of the changeover. Besides, you busy expanding the business, aren't you? It takes bad times to make you take a better look at the alternatives and to have the time to consider bringing them in.
The silver lining of recessions is that they prune dead wood. Weak companies go to the wall (unfortunately, sometimes pulling good ones down with them), leaving the survivors healthier when the recession is over. If some of the dead wood is M$ systems installed from sheer conservatism, let us cheer for it.
Yes, he could not patent the concept of a teleporter, though he could patent a particular implementation. An idea does NOT need to be implementable (at the time) to be patentable. (Except, in the case of the USPTO, for perpetual motion machines, for which they demand a working model to keep the whackos at bay).
In his seminal article about geosynchronous satellites, published in 1945, Arthur C Clarke described the need for a synchroniser for TV signals transmitted by satellite, even though neither the satellite nor the technology to build the synchroniser existed at the time.
When the technology to build digital synchronizers arrived in the early seventies, the first company to build one was unable to patent the idea because of Clarke's prior art. Which was lucky for the company which built the second one, for which I worked a little time later.
When I went round JET about 2 years ago, the tour guide said that, just for interest, they had set up a project plan for how long it would take, if they were given all the resources they could ask for, to get to commercial fusion power. The answer came out that the first production fusion power station would go on grid in 27 years, 6 months. The bottleneck, apparently, is not the plasma containment etc which will be researched at ITER, but the materials research to make the containment vessel last. Basically, they are confident that they could build a reactor that would work and deliver net energy. But what they don't yet know is how to build such a machine with a long enough working life and low enough maintenance cost to pay for itself.
Scientific American many years ago has an article with outline plans for such a thing. A spherical tank of liquid beryllium, spinning so as to contain a vortex and with helium bubbling through it. Drop deuterium/tritium pellets down the vortex, and zap them with a laser as they reach the centre of the sphere. Neutrons hit beryllium, transfer heat, create more tritium. Helium bubbles absorb shock waves, and flush unused/created deuterium and tritium for recycling.
It depends what you mean by "ignition". The JET has contained plasmas for times of the order of minutes with significant energy output from fusion. The output did not compensate for the amount of energy necessary to set the system up, but nevertheless there has been significant energy generation from fusion, which counts to me as ignition. The ITER project, its successor, is planned to have a net energy output.
Slashdot Mirror
Because the galaxy is not a point mass. Most ordinary star/planet modelling is based on viewing each object as a sphere, which behaves as a point mass at the centre. But when you penetrate inside another body, as two galaxies do when they collide, this simplification no longer applies. Some of the mass of the "other" galaxy moves behind the penetrating galaxy, slowing it down rather than, as the point mass model would suggest, continuing to accelerate into the centre. In the simplest model, of inter-penetrating spheres, gravity no longer has an inverse square law but an inverse linear law. Of course, galaxies are not uniform spheres, and the modelling is much harder. However, it is widely accepted that when two galaxies collide, they merge and the vast majority of the mass forms a single galaxy - though clusters may be flung out. If the galaxies are of broadly similar masses, the distinctive spiral structure is wiped out and the merged result becomes an elliptical galaxy for a few hundred million years before the spiral structure re-establishes.
Google "andromeda collisions" for simulations of the collision between our galaxy and the Andromeda galaxy in about 3 billion years.
Basically, size. The dinosaurs were all largeish - turkey-sized or bigger - with the exception of thos who seem to have evolved into birds, and may have been much smaller because of the nifty invention of feathers. The only mammals at the time were small, shrew-like animals. It is not unreasonable to think that small beasts could survive, scavenging of the dead big beasts, where big beasts could not.
The possibilities for hacking other people's tattoos are frightening. You can hardly go around keeping a continuous watch on them, especially on your back. Imagine going to work at school labelled "Crack $5/bag".
What I like about this is not so much the potentially faster upgrade as the ability to contribute a bit to others. The six-monthly upgrades are are rate enough that I don't mind if they are a bit slow - not that they have been. But I am very conscious that I am using other people's freely given bandwidth and I am pleased to be able to give some back.
Does anybody know if I can force my various machines to cross-peer from each other? If I update one first, I don't want the others searching the Net for peers - they should just copy from the first.
One word I would like to see get more use is "Sophont", coined by Poul Anderson (actually by his wife, I believe, but his name is on the books) to mean any life intelligent enough to share what we currently call "human rights" but will have to stretch when we meet intelligent ETs.
You have a very mediaeval understanding of the word "King". Sure, that is the way they used to be. But democracy has, quite correctly, slid all the power over to elected institutions. Walter Bagehot wrote an influential book on the British Constitution in which he distinguished the Efficient from the Dignified parts of government. The Efficient part does the work, but every country needs a Dignified pare. This includes flags, soldiers in archaic uniforms, lots of saluting, bugle calls and running around. Constitutional monarchies have left the monarch as entirely part of the Dignified part of government, representing the country without having to do anything much. This leaves everybody free to criticize the politicians without attacking their symbolic head.
It is, in my opinion, a (minor) defect of the US constitution that the President is the head of both Efficient and Dignified sides of the government. This means that he has to waste time with, for example, pinning on medals. And on the other side, those receiving medals may not be best pleased to get them from a politician they may abhor.
The concept of a King never was what the fairy tales imagined, and has moved on a long way since the King was a position of power. It is now purely a symbolic position.
Constitutional monarchs are figureheads - as responsible for the laws passed by the parliaments of their countries as the flag is. In the UK at least, the Queen reigns but does not rule: her role is entirely ceremonial (well, almost: in certain very obscure circumstances she can be a tie breaker). Monarchies today are not what they were in the thirteenth century.
I don't think that any of this is the King's doing. It is the major parties which have made hyper-loyalty to the King a kind of shibboleth. A bit like the McCarthy era in the US, when it almost became UnAmerican to admit to having a left hand. You protest your loyalty to the King loud and long to prove your patriotism, then when anybody accuses you of thinks like taking bribes, you call them unpatriotic. So there is a huge "more respectful than thou" campaign going on - but none of it supported in any way by the King himself.
When s/he says that "people thought", GP I hope means that some people thought, not that all people thought. People like Dr Dionysius Lardner http://en.wikipedia.org/wiki/Dionysius_Lardner, self-appointed pundit and critic of Brunel. Such people still exist, and get credibility amongst those without scientific or engineering training. Selective reporting and mindless extrapolation will always generate a result sensational enough to get some headlines for those in search of such.
Which is why I classified astronomy, of which astrophysics is a part, as an observational science in the very next sentence. Much of biology is also observational, but increasing amounts are becoming experimental, for example as people are able to construct small scale repeatable ecosystems.
I was very explicitly trying to make the point that not all science is experimental. Collecting a large number of observations of equivalent objects is also science. But observational science requires a large number of essentially equivalent observations: watch a planet for years, observe tens of thousands of stars, collect tens of thousands of fossils, observe strata at hundreds of locations. Economics cannot do that: there is only one world economy, and national and local economies are too different to get comparable observations.
Which just shows that economics and finance are not, in any sense we generally recognise, sciences. Just using mathematics and graphs does not make something a science. Economics obviously does not meet the criteria of an experimental science like physics or chemistry: you cannot perform repeatable experiments. Nor does it meet the criteria of an observational science like astronomy or palaeontology: huge numbers of essentially comparable observations (take millions of star photos, collect rooms full of fossils).
Aside from these problems, economics suffers from insufficient isolation: the elements being measured react not only to the measurement but to the theories being made about the measurements.
Therefore it is not reasonable to relate any problems in the economy and financial markets to the body of knowledge we generally call science.
But that is based on the assumption that the CMB is, indeed, the relic of the Big Bang, which is one of the assumptions referenced. And that the Hubble shift is, indeed, caused by the expansion of the Universe. Of course, I do not really doubt this, but these are still very indirect deductions. One could imagine a measurement which cast doubt on all of them - e.g. speed of light changing with time, in which case the whole Universe would probably need to be rescaled.
If firmly mounted, the drives are very shock tolerant. What people don't realize is how high the G force generated when hard object like a drive hits a hard object like a table. You can get instantaneous tens, possibly hundreds of Gs. Earthquakes can generate several Gs, but not tens. Problems tend to occur when structures have forces in unexpected directions (walls are bad at shifting sideways, masonry doesn't like decompression) or when you get resonance with the oscillation, which builds up the energy. Disk drives don't have these failure modes.
But how does one answer "The question is not meaningful because I do not accept the existence of evil spirits". You could say that this implies and answer No, but it seems to me that am meaningless question does not deserve even a default answer: GIGO applies: if the input is garbage, anything derived from it is garbage, even if it appears to have meaning.
Fine. Now how do you expect a dumb processor to do what a clever programmer cannot? If we knew how to build machines that could do this, we would have done it. But to allow for parallelism, you have to understand the why of the system, not the what. And that gets lost between design and code.
Which is great - if you rewrite your software for such an architecture. Which is what the original article was saying.
*Not* minicab drivers. The ones who have to take The Knowledge are the licensed cab drivers of London, who usually drive the famous Black Cabs (nowadays not always black), and are allowed to pick up passengers who hail them on the street. Minicab drivers is the term used exactly for those those who are *not* licensed drivers who have done The Knowledge. You have to book them (e.g. by phone) and there are far fewer controls over them. And all this applies only in London.
Having worked in the industry, they are already transitioning to 10bits/sample, and may go to 12, but I really don't expect them to go to 16. And the standard "4k" size is 4k x 3k. Bot of those shrink your numbers a bit. And they haven't really developed the compression for stereo, which ought to be extremely efficient because the two images are nearly identical.
I have a Facebook account created when someone asked me to look at their pages. I haven't logged in in certainly one, maybe two, possibly three years. I would never see anything serve on me there.
I probably have accounts on a score or more other forums and so on that I signed up to, used for a short while, and either got bored or achieved what I needed. Do I have to keep monitoring all of these in case someone chooses to post an important message?
The article does not state whether the court required the plaintiff to show that the defendant was currently active on Facebook, or even that the question was asked. That strikes me as an important point. If you could show that the defendant regularly used their Facebook account both before /and after/ the attempted service, the reliability of the claimed service becomes much greater.
I think, and hope, that it is more a case of the downturn jolting a lot of people out of their ruts. However much you may think or even know that *nix is better than Windows, it is a big decision to change a company from one to the other. In good times, you can afford the Windows tax, and pay it just to avoid the hassle of the changeover. Besides, you busy expanding the business, aren't you? It takes bad times to make you take a better look at the alternatives and to have the time to consider bringing them in.
The silver lining of recessions is that they prune dead wood. Weak companies go to the wall (unfortunately, sometimes pulling good ones down with them), leaving the survivors healthier when the recession is over. If some of the dead wood is M$ systems installed from sheer conservatism, let us cheer for it.
Yes, he could not patent the concept of a teleporter, though he could patent a particular implementation. An idea does NOT need to be implementable (at the time) to be patentable. (Except, in the case of the USPTO, for perpetual motion machines, for which they demand a working model to keep the whackos at bay).
In his seminal article about geosynchronous satellites, published in 1945, Arthur C Clarke described the need for a synchroniser for TV signals transmitted by satellite, even though neither the satellite nor the technology to build the synchroniser existed at the time.
When the technology to build digital synchronizers arrived in the early seventies, the first company to build one was unable to patent the idea because of Clarke's prior art. Which was lucky for the company which built the second one, for which I worked a little time later.
When I went round JET about 2 years ago, the tour guide said that, just for interest, they had set up a project plan for how long it would take, if they were given all the resources they could ask for, to get to commercial fusion power. The answer came out that the first production fusion power station would go on grid in 27 years, 6 months. The bottleneck, apparently, is not the plasma containment etc which will be researched at ITER, but the materials research to make the containment vessel last. Basically, they are confident that they could build a reactor that would work and deliver net energy. But what they don't yet know is how to build such a machine with a long enough working life and low enough maintenance cost to pay for itself.
What we need is some CERN-scale collaboration on this so that we can possibly help to alleviate the energy strains on the global populace.
You means something like JET http://www.jet.efda.org/ or ITER http://www.iter.org/ ?
Scientific American many years ago has an article with outline plans for such a thing. A spherical tank of liquid beryllium, spinning so as to contain a vortex and with helium bubbling through it. Drop deuterium/tritium pellets down the vortex, and zap them with a laser as they reach the centre of the sphere. Neutrons hit beryllium, transfer heat, create more tritium. Helium bubbles absorb shock waves, and flush unused/created deuterium and tritium for recycling.
It depends what you mean by "ignition". The JET has contained plasmas for times of the order of minutes with significant energy output from fusion. The output did not compensate for the amount of energy necessary to set the system up, but nevertheless there has been significant energy generation from fusion, which counts to me as ignition. The ITER project, its successor, is planned to have a net energy output.