Both of my parents have moved to remote places, with unique communities, and are rather isolated in some ways. Had I grown up in either of these places, I think I would have wanted to escape in some way. I might have longed for something different and looked at how to get out, geographically, socially, and regarding lifestyle and mentality.
At this point in my life, I am only a visitor in these places. But arriving in each one, I get the feeling of being pulled into a black hole, with little communication to the rest of my life, and not sure how to connect the experience to who I am. At the same time, I am adaptable, and arriving, and within the experience, it has an integrity and a quality to it that is quite nice. But the boundaries are difficult. I can't think my way into it from outside, or out of it from inside.
So I have slowly worked on the problem over the years by looking carefully at the boundaries. In the remote town in California where my father lives, for example, I look to see whether there are surrounding communities that might have some life to them. I try to find things in common to other places regarding environment and landscape. I plan trips there with an exit strategy, and friends and other family flanking it. Certainly this is also quite personal, and relates to my own experience of family and who I am there, and who I am seen as. I am starting to try the same strategy with my mother's house in Iowa. There, the boundaries are physical, but there is also a strong ideological barrier that is uncomfortable to me. Is there something within that I can relate to? I find pieces of interest to that community that I might interpret in a different way, but still find interesting.
Is such an elaborate process necessary? Maybe I will reach a point where it will seem smaller and less important, but somehow this work is necessary. The other option is to say that visiting my family is too difficult, and no common ground can be found, but I don't want to do that.
On the Petrolia side, there is the natural environment. The trees, the river, the ocean.
On the MUM/Fairfield side, there is the nearby Mississippi river. There are coffee shops in Fairfield. Ideologically, MUM is more challenging. The Maharishi is a figure that I just have a very hard time appreciating. And the closed mentality fosters an inside/outside split that is hard to overcome. One of the Maharishi's main texts he interpretted and based his power around has been the Baghavad Gita. I think this is something I could become interested in.
Monday, August 29, 2011
Sunday, August 28, 2011
Back to the mess
I have to finish a paper for a conference by Wednesday night. It is on the measurements relating to Touschek lifetime and momentum acceptance. There's an analysis of data to be done, and general writing and preparation of the paper. I really don't want to work on it.
Why don't I want to do it? Its late, I know. A paper needs to be written, and doing an analysis at the last minute can derail me from the process of fixing figures, adding references, and putting a clear narrative together. But its also that I've gotten myself out of thinking of this topic, and am wary of going back. It was my compromise. I will not leave accelerator physics entirely. I will do some work in this field, but move outward at the same time. But the topic is a mess for me. It is a personal mess in that my own files and documents and the relevant equations are not in such clear order. And a general historical mess in that it relates to the topic of dynamic aperture and sextupole optimization which is an unsolved problem. That question of dynamic aperture and stability has been the piece that I have slowly worked on, and tried to lay out a personal groundwork, so I don't feel so lost working in that area. Maybe this is a reflection of the fact that I didn't really finish this process.
So, my own angle on Touschek lifetime and measurement that I would like to get across is that the measurements are a diagnostic for the various lattice optimizations. There is both vertical emittance reduction goals, and increase of momentum acceptance via sextupole optimization. Stating clearly what these mean, and having measurements to ground discussion and results puts this other more nebulous "accelerator physics" activity onto a ground that relates to the goal of the machine- production of stable, long lived synchrotron radiation.
Why don't I want to do it? Its late, I know. A paper needs to be written, and doing an analysis at the last minute can derail me from the process of fixing figures, adding references, and putting a clear narrative together. But its also that I've gotten myself out of thinking of this topic, and am wary of going back. It was my compromise. I will not leave accelerator physics entirely. I will do some work in this field, but move outward at the same time. But the topic is a mess for me. It is a personal mess in that my own files and documents and the relevant equations are not in such clear order. And a general historical mess in that it relates to the topic of dynamic aperture and sextupole optimization which is an unsolved problem. That question of dynamic aperture and stability has been the piece that I have slowly worked on, and tried to lay out a personal groundwork, so I don't feel so lost working in that area. Maybe this is a reflection of the fact that I didn't really finish this process.
So, my own angle on Touschek lifetime and measurement that I would like to get across is that the measurements are a diagnostic for the various lattice optimizations. There is both vertical emittance reduction goals, and increase of momentum acceptance via sextupole optimization. Stating clearly what these mean, and having measurements to ground discussion and results puts this other more nebulous "accelerator physics" activity onto a ground that relates to the goal of the machine- production of stable, long lived synchrotron radiation.
Thursday, August 18, 2011
online
Can we get beyond talking about people "living online"?
Along the lines of this post from Crooked Timber, I think the metaphor has gone too far.
Yes, the modes of communication have expanded, and there things that we do that are interacting directly with software (and perhaps with others in a delayed way, such as blogging!), rather than directly with people, but we are not living online.
What does the question "are you online?" mean these days? Yes, we may be available or not to communicate via a variety of channels, but no "we" are not online. I'm still here, in this room, breathing, as usual.
Perhaps "living online" is used in the sense of "living in one's head", which is generally not though of as such a good thing to do.
I guess, as a general topic, and as a source for personal time and space and energy management, I want to limit the extent to which one says "we" are online. Things like Facebook have an almost avatar like quality to them, where a certain amount of our information is packaged and available to others even when we are not available. It sort of represents us. How this fits in is something to continue to struggle with, but I just need to remind myself at times, that I am here, and these are modes of communication. We do say that google can be like extended memory, but I just don't want to go down that path. Perhaps people of the future will have some kind of choice like this to make, but for myself, I am who I am, not changed so much, but with a few more communication and knowledge access tools.
Along the lines of this post from Crooked Timber, I think the metaphor has gone too far.
Yes, the modes of communication have expanded, and there things that we do that are interacting directly with software (and perhaps with others in a delayed way, such as blogging!), rather than directly with people, but we are not living online.
What does the question "are you online?" mean these days? Yes, we may be available or not to communicate via a variety of channels, but no "we" are not online. I'm still here, in this room, breathing, as usual.
Perhaps "living online" is used in the sense of "living in one's head", which is generally not though of as such a good thing to do.
I guess, as a general topic, and as a source for personal time and space and energy management, I want to limit the extent to which one says "we" are online. Things like Facebook have an almost avatar like quality to them, where a certain amount of our information is packaged and available to others even when we are not available. It sort of represents us. How this fits in is something to continue to struggle with, but I just need to remind myself at times, that I am here, and these are modes of communication. We do say that google can be like extended memory, but I just don't want to go down that path. Perhaps people of the future will have some kind of choice like this to make, but for myself, I am who I am, not changed so much, but with a few more communication and knowledge access tools.
Wednesday, August 10, 2011
What Technology Wants
I recently read Kevin Kelly's "What Technology Wants". I think my biggest complaint is the lack of humility when it comes to the big ideas, particularly with respect to the ill-defined "technium". The claims are grand and vague on the one hand, and at the same time it is stated that it is expected that these concepts will go through a number of iterations and changes over time. Stephen Wolfram's "A New Kind of Science" had a similar grandiosity to it. It allows the author some maneuver room later to claim further developments under his/her rubric.
I think one can classify this book under the category of books where the author holds two divergent view points and tries to build some kind of narrative that encompasses the two. In this case, Kelly seems to have some kind of Christian God viewpoint that he is seeking to capture in the "Technium", and at the same time has the computer science and general science background that is perhaps less able to make statements about overall meaning or goal orientation in the universe. I think this dissonance can occur in scientists who also have religious commitments. John Hagelin's writings connecting Transcendental Meditation to Unified field theories is one example. Frank Tipler's "Physics of Immortality" is another. Fritjof Capra's "The Tau of Physics" is another example, but I think less difficult to swallow. (Actually these first two struck me as so strange that I doubted the honesty of the authors, whereas with Capra, and here with Kelly, one feels a fervency that doesn't seem so forced, even if the logic is flawed. Perhaps the real dishonesty simply comes in with the claiming that such an integration has been achieved, and this could indeed relate to high levels of self-deception.) In all of these works, it would be nice to see a section evaluating how well the author believes such a synthesis has worked. But perhaps the existence of such a section would have a rhetorical effect of diminishing the power of the hoped for unification.
I did really appreciate Kelly's discussion of the Amish, and in general about ways of thinking about adoption of technology and the imperative that one (individually and collectively) have the option of saying no sometimes. And his discussion of the "Technium" did make me want to seek out a more precise definition of some collection of human created artifacts and tools including some ideas, culture, and laws perhaps, that might usefully be viewed as having a sort of unity to it. The identification of this not well articulated entity with a biological entity did not seem to be so well founded. Clearly it is the recent widespread adoption and development of some internet communication technologies that provides the ground for such speculations and theorizing. In any case, it seems to be the same kind of thinking in conspiracy theories where agency is ascribed to some larger entity that may contain people as elements. Certainly one can find some truth out of this kind of thinking, but it seems to often lead to more errors and less clarity than it illuminates.
(Update... here is an interview of K.K. on his explicit religious views about the "technium")
Thinking a little further, I think that what we should celebrate (and engage with) in this book, is the fact that Kelly is articulating a system of values here. In particular, he is willing to say and argue as why technology is intrinsically "good". I'll have to track down the relevant quote, but the basic point he makes is that each technology has a possibility to be used in both positive and negative ways. However, the very existence of this choice is what tips it to the positive. Do I believe this? Its not obviously wrong. And in fact it may be part of what motivates me to contribute to the world of ideas and technology. Its hard to say that its always true, though. Can we stomach it for guns, say? A gun allows you the new choice to either defend yourself, or to injure/kill someone else. There are certainly some who would argue that this choice is not a net benefit for society. For the case of the Amish, Kelly wants to say that their choices to reject a given technology are appropriate for them, but not necessarily overall. So his encouragement of this practice doesn't invalidate his larger point. What about the bigger, more questionable technologies (genetic engineering, nanotechnology, and nuclear). I think he wants to say that even here, more choice is better, even if those choices seem pretty odd. (With nuclear weapons, one has the new choice to blow up this city, or that city. Ok, maybe one can conceive of positive options, but it seems likely that as a whole, the options created are not really a net gain.)
Anyway, it seems to be a somewhat slim blanket justification, but it is better than a complete lack of engagement in ethics, which is the norm for technologists.
Qualifying this somewhat... I guess, the main point (or guess, or suggestion) Kelly makes is that technology is slightly more "good" than "bad". So even if sometimes the creation of more options isn't "good", if the options produced by most technologies are on the whole "good", then it could still come out ahead. The question then might become, what is this unified thing that is slightly more good than bad? Is it really one thing, or have the good things just somehow been selected. Are repugnant political philosophies that yield great harm on humanity considered part of the technium? Or does he really just have something like the current manifestation of the internet and the associated technologies that are required to create a sort of closure surrounding that?
****
Update, Aug. 30, 2012. Here is an interesting article critiquing the book from the cybergology blog.
I think one can classify this book under the category of books where the author holds two divergent view points and tries to build some kind of narrative that encompasses the two. In this case, Kelly seems to have some kind of Christian God viewpoint that he is seeking to capture in the "Technium", and at the same time has the computer science and general science background that is perhaps less able to make statements about overall meaning or goal orientation in the universe. I think this dissonance can occur in scientists who also have religious commitments. John Hagelin's writings connecting Transcendental Meditation to Unified field theories is one example. Frank Tipler's "Physics of Immortality" is another. Fritjof Capra's "The Tau of Physics" is another example, but I think less difficult to swallow. (Actually these first two struck me as so strange that I doubted the honesty of the authors, whereas with Capra, and here with Kelly, one feels a fervency that doesn't seem so forced, even if the logic is flawed. Perhaps the real dishonesty simply comes in with the claiming that such an integration has been achieved, and this could indeed relate to high levels of self-deception.) In all of these works, it would be nice to see a section evaluating how well the author believes such a synthesis has worked. But perhaps the existence of such a section would have a rhetorical effect of diminishing the power of the hoped for unification.
I did really appreciate Kelly's discussion of the Amish, and in general about ways of thinking about adoption of technology and the imperative that one (individually and collectively) have the option of saying no sometimes. And his discussion of the "Technium" did make me want to seek out a more precise definition of some collection of human created artifacts and tools including some ideas, culture, and laws perhaps, that might usefully be viewed as having a sort of unity to it. The identification of this not well articulated entity with a biological entity did not seem to be so well founded. Clearly it is the recent widespread adoption and development of some internet communication technologies that provides the ground for such speculations and theorizing. In any case, it seems to be the same kind of thinking in conspiracy theories where agency is ascribed to some larger entity that may contain people as elements. Certainly one can find some truth out of this kind of thinking, but it seems to often lead to more errors and less clarity than it illuminates.
(Update... here is an interview of K.K. on his explicit religious views about the "technium")
Thinking a little further, I think that what we should celebrate (and engage with) in this book, is the fact that Kelly is articulating a system of values here. In particular, he is willing to say and argue as why technology is intrinsically "good". I'll have to track down the relevant quote, but the basic point he makes is that each technology has a possibility to be used in both positive and negative ways. However, the very existence of this choice is what tips it to the positive. Do I believe this? Its not obviously wrong. And in fact it may be part of what motivates me to contribute to the world of ideas and technology. Its hard to say that its always true, though. Can we stomach it for guns, say? A gun allows you the new choice to either defend yourself, or to injure/kill someone else. There are certainly some who would argue that this choice is not a net benefit for society. For the case of the Amish, Kelly wants to say that their choices to reject a given technology are appropriate for them, but not necessarily overall. So his encouragement of this practice doesn't invalidate his larger point. What about the bigger, more questionable technologies (genetic engineering, nanotechnology, and nuclear). I think he wants to say that even here, more choice is better, even if those choices seem pretty odd. (With nuclear weapons, one has the new choice to blow up this city, or that city. Ok, maybe one can conceive of positive options, but it seems likely that as a whole, the options created are not really a net gain.)
Anyway, it seems to be a somewhat slim blanket justification, but it is better than a complete lack of engagement in ethics, which is the norm for technologists.
Qualifying this somewhat... I guess, the main point (or guess, or suggestion) Kelly makes is that technology is slightly more "good" than "bad". So even if sometimes the creation of more options isn't "good", if the options produced by most technologies are on the whole "good", then it could still come out ahead. The question then might become, what is this unified thing that is slightly more good than bad? Is it really one thing, or have the good things just somehow been selected. Are repugnant political philosophies that yield great harm on humanity considered part of the technium? Or does he really just have something like the current manifestation of the internet and the associated technologies that are required to create a sort of closure surrounding that?
****
Update, Aug. 30, 2012. Here is an interesting article critiquing the book from the cybergology blog.
Thursday, April 14, 2011
time
There is a rhythm to my life in France that seems to involve patience in new ways than I have experienced previously. It seems to require that I put faith into systems and processes that move slower than I am accustomed to working with. And at the same time, these processes seem hidden, and my instinct is to doubt and wonder whether they are in fact real, even though time and again they show progress and stability. It is something like observing the process of growth of a plant from a seed. There is a logic and robustness to the process, and unless one has watched this particular kind of seed grow before, one can't really look at the current state and figure out where it will go. Instead, one just continues to water, continues to protect, and has faith that something with come of all this.
Monday, March 14, 2011
Back to Cartwright
I seem to keep coming back to reading "How the Laws of Physics Lie" and "The Dappled World".
I think the reason is that I don't usually get very far. I get bogged down, skip ahead, and feel annoyed. I get a little out of it, but its dense, and the meaning of an essay is often not what I thought it was going to be. I didn't realize that the examples such as the BCS theory of superconductivity, and some laser physics (Also the measurement problem and the relations between classical and quantum systems) were gone into in such detail. The exposition is actually pretty clear, but you don't often know so much detail is on its way.
Anyway, I've finally been getting to the end and actually understanding more of it. In the end, it is more inspirational for a practicing physicist than I thought. The essay on the Quantum measurement problem in HLPL ends with stating that one should take the formalism of quantum statistical mechanics seriously which treats mixtures and superpositions on the same footing. This leaves physicists with the job of figuring out which cases have unitary evolution and which don't. And I think this is in line with the way one analyzes a new phenomena. Take a look at it. Use what we already know. Make some guesses. Test them. Refine them. An approach to learning about new things that involves actually studying those things.
And the discussion about capacities, vs. laws, is not so radical in the end. Perhaps from a philosophy perspective it is. But thinking of electric charge and gravitational mass as imbuing capacities on electrons rather than laying out laws of motion is just the way one thinks about these things. We learn about certain aspects of things, and then we may try to isolate it such that just that one property comes into play. This is what fundamental experiments are about. And we do learn some real about these things. The question may arise as to whether the same effect occurs in different environments, or exactly how the forces or whatever other properties combine when acting in concert. And this way of looking at physical knowledge puts it in the same box as other knowledge we have. There still may be questions of reduction or relationships between different kinds of knowledge, but the starting point seems good.
I must say I'm still not sure I get what she means by nomological machine. She makes a "strong claim" in "The Dappled World" that behind every regularity in the world is a nomological machine. Let's say we are in Switzerland where trains are highly reliable. The matching of the trains to the schedule is a nomological machine? I suppose it is. And the fact that my car (usually) works is a nomological machine. And atoms are nomological machines. And proteins are nomological machines. And a market is a nomological machine. And a beam of light is a nomological machine.
Anyway, just to remind that getting into certain details can be demotivating if one gets stuck in them, but if a topic actually relates to the world and the way things really work, then understanding it will lead to more tools and more clarity in the end. Which is to say that previously, reading this made me shut down certain ways of thinking, but now I find it mainly adds.
Apparently Philip Anderson may have had some trouble following "Dappled World" as well.
I just read Anderson's review (see here). Wow, that's pretty intense. He refers a lot to the feeling he gets about it. "One gets the feeling" he states a lot, without actually quoting many passages, or covering arguments. I must admit, that I sometimes had these same "feelings". But reading more closely, I often found that Cartwright was saying something more precise and more interesting than I initially thought.
Here are other reviews of The Dappled World.
Finally, once one digests some of the seemingly right arguments, one would like to see engagement of other authors. Here's some essays doing this. In particular, I'd like to understand this one by Carl Hoefer in defense of "fundamentalism". He concludes with
Another way to get at the question is to take this fact about hydrogen seriously and see how much it says. Using the capacity language, we say that we know the capacities of hydrogen atoms, and also that we find hydrogen atoms all of the place. And less us take it a step further, and say we know the capacities of molecules, and that we also find these things all over the place. Is physics the domain that is responsible for such knowledge? Its certainly a good part of it, but I think its reasonable to say that the methods and ideas of chemistry are also involved in this knowledge. So I'd need to understand a little better what is meant by a law in the expression "fundamental law" to see if it captures the knowledge we have about the atomic and molecular basis of matter.
I think the reason is that I don't usually get very far. I get bogged down, skip ahead, and feel annoyed. I get a little out of it, but its dense, and the meaning of an essay is often not what I thought it was going to be. I didn't realize that the examples such as the BCS theory of superconductivity, and some laser physics (Also the measurement problem and the relations between classical and quantum systems) were gone into in such detail. The exposition is actually pretty clear, but you don't often know so much detail is on its way.
Anyway, I've finally been getting to the end and actually understanding more of it. In the end, it is more inspirational for a practicing physicist than I thought. The essay on the Quantum measurement problem in HLPL ends with stating that one should take the formalism of quantum statistical mechanics seriously which treats mixtures and superpositions on the same footing. This leaves physicists with the job of figuring out which cases have unitary evolution and which don't. And I think this is in line with the way one analyzes a new phenomena. Take a look at it. Use what we already know. Make some guesses. Test them. Refine them. An approach to learning about new things that involves actually studying those things.
And the discussion about capacities, vs. laws, is not so radical in the end. Perhaps from a philosophy perspective it is. But thinking of electric charge and gravitational mass as imbuing capacities on electrons rather than laying out laws of motion is just the way one thinks about these things. We learn about certain aspects of things, and then we may try to isolate it such that just that one property comes into play. This is what fundamental experiments are about. And we do learn some real about these things. The question may arise as to whether the same effect occurs in different environments, or exactly how the forces or whatever other properties combine when acting in concert. And this way of looking at physical knowledge puts it in the same box as other knowledge we have. There still may be questions of reduction or relationships between different kinds of knowledge, but the starting point seems good.
I must say I'm still not sure I get what she means by nomological machine. She makes a "strong claim" in "The Dappled World" that behind every regularity in the world is a nomological machine. Let's say we are in Switzerland where trains are highly reliable. The matching of the trains to the schedule is a nomological machine? I suppose it is. And the fact that my car (usually) works is a nomological machine. And atoms are nomological machines. And proteins are nomological machines. And a market is a nomological machine. And a beam of light is a nomological machine.
Anyway, just to remind that getting into certain details can be demotivating if one gets stuck in them, but if a topic actually relates to the world and the way things really work, then understanding it will lead to more tools and more clarity in the end. Which is to say that previously, reading this made me shut down certain ways of thinking, but now I find it mainly adds.
Apparently Philip Anderson may have had some trouble following "Dappled World" as well.
I just read Anderson's review (see here). Wow, that's pretty intense. He refers a lot to the feeling he gets about it. "One gets the feeling" he states a lot, without actually quoting many passages, or covering arguments. I must admit, that I sometimes had these same "feelings". But reading more closely, I often found that Cartwright was saying something more precise and more interesting than I initially thought.
Here are other reviews of The Dappled World.
Finally, once one digests some of the seemingly right arguments, one would like to see engagement of other authors. Here's some essays doing this. In particular, I'd like to understand this one by Carl Hoefer in defense of "fundamentalism". He concludes with
To engineers and experimentalists, I commend Cartwright’s philosophy of science wholeheartedly. But I hope to have made space for theoreticians and philosophers of physics to keep their faith in a world with fundamental physical laws.As a quick summary of Hoefer's article, he says that one can keep the fundamentalist approach but deny that some kinds of reductionism may be possible. What I wonder then is about the terminology of laws. Cartwright already says that we learn about capacities. I'd assume that the hydrogen atom in the dewar and the hydrogen atom in the hallway and the hydrogren atom in a distant galaxy all have the same capacities. (It does seem a bit odd to say that a hydrogen atom has the capacity to form the states specified by the Shroedinger equation with the central force potential term in its Hamiltonian, but maybe this is just what one must say.) I guess the question to address is how to relate such facts to programs in which we take electrodynamics, quantum mechanics, fluid mechanics, thermal physics, statistical mechanics, etc. and try to say that in some sense these theories "govern" matter.
Another way to get at the question is to take this fact about hydrogen seriously and see how much it says. Using the capacity language, we say that we know the capacities of hydrogen atoms, and also that we find hydrogen atoms all of the place. And less us take it a step further, and say we know the capacities of molecules, and that we also find these things all over the place. Is physics the domain that is responsible for such knowledge? Its certainly a good part of it, but I think its reasonable to say that the methods and ideas of chemistry are also involved in this knowledge. So I'd need to understand a little better what is meant by a law in the expression "fundamental law" to see if it captures the knowledge we have about the atomic and molecular basis of matter.
Tuesday, January 18, 2011
information vs. story/meaning
Ok, another post to motivate myself to get back to some work I should be doing.
First about information in general: I was just realizing that in some sense, I never really got my head around what this actually means. We are saying that information is key. And we develop information technologies, etc. But what is information? There is the physics definition in terms of entropy, but what is the more practical definition? I suppose it would have to do with a representation of something existing in the real world? So why are these representations so important? I guess because some things are set up such that once one has such a representation, one can impact the thing itself? A person has a set of information associated with them that is deemed important. And this information represents certain aspects of that person. And with this information, the person can be affected. If one has information about a country, then one may affect that country in certain ways.
On another end of this topic, I've been realizing that I've had this concept of work where I just need to collect together the appropriate information associated with some topic, and then I feel that my job is mostly done. Now I need to put together a report on beam lifetime, and I'm realizing that there's a lot to be done even though in some sense most of what I thought of as the work, is already done. I need to put the report together which means presenting the plots in certain ways, labelling stuff, etc. I think that other people would keep such a report, or a paper, or some other final product more in mind as they do the work of assembling the information. Then it gets put into the proper form along the way. I suppose there's a balance. Collecting stuff with such a clear final goal in mind may also skew the results and make them less robust. But it may also be more understandable, and have more impact. I could learn to direct my work a bit more towards goals, and would probably save myself some work, and get more done. Pure information is not so useful if you can't do something with it.
Do these two different queries/angles on information inform each other? I will have to think further on this.
(Incidentally, this question about the nature of information was partially prompted by reading stuff by Jared Lanier. I've been finding a lot of his writing a nice anecdote to some of what scares me online these days. Thinking more clearly about ideology and about our opinions on "information" seems useful. Perhaps more later.)
First about information in general: I was just realizing that in some sense, I never really got my head around what this actually means. We are saying that information is key. And we develop information technologies, etc. But what is information? There is the physics definition in terms of entropy, but what is the more practical definition? I suppose it would have to do with a representation of something existing in the real world? So why are these representations so important? I guess because some things are set up such that once one has such a representation, one can impact the thing itself? A person has a set of information associated with them that is deemed important. And this information represents certain aspects of that person. And with this information, the person can be affected. If one has information about a country, then one may affect that country in certain ways.
On another end of this topic, I've been realizing that I've had this concept of work where I just need to collect together the appropriate information associated with some topic, and then I feel that my job is mostly done. Now I need to put together a report on beam lifetime, and I'm realizing that there's a lot to be done even though in some sense most of what I thought of as the work, is already done. I need to put the report together which means presenting the plots in certain ways, labelling stuff, etc. I think that other people would keep such a report, or a paper, or some other final product more in mind as they do the work of assembling the information. Then it gets put into the proper form along the way. I suppose there's a balance. Collecting stuff with such a clear final goal in mind may also skew the results and make them less robust. But it may also be more understandable, and have more impact. I could learn to direct my work a bit more towards goals, and would probably save myself some work, and get more done. Pure information is not so useful if you can't do something with it.
Do these two different queries/angles on information inform each other? I will have to think further on this.
(Incidentally, this question about the nature of information was partially prompted by reading stuff by Jared Lanier. I've been finding a lot of his writing a nice anecdote to some of what scares me online these days. Thinking more clearly about ideology and about our opinions on "information" seems useful. Perhaps more later.)
Tuesday, January 11, 2011
optics and light representation
Well, in accordance with this blog title, I move slowly, and as I noted recently, have been moving into the radiation end of things. Its somewhat of a shock to go from such a specialized literature of accelerator physics and beam physics to the extremely vast literature of optics and light.
On the other hand, accelerator physics was never such a well defined concept. It is well defined from the sense that it is a collection of all the physics one may need in analyzing, building, designing or improving a particle accelerator. But its a rather mixed bag of classical mechanics, relativity, electricity and magnetism, and material science.
On to radiation, one has Maxwell's equations describing the evolution of electric and magnetic fields. However, one often represents light via a complex scalar field, or via a Wigner function, when coherence properties are required. Currently I'm trying to understand all this terminology related to Fourier Optics. One has a point spread function. One has an optical transfer function. One has an amplitude transfer function. Does one gain something new with these different representations? With the Wigner function, there's a partial interpretation in terms of the distribution of photons. But, being sometimes negative, its not such a clear interpretation. There are operator representations for quantum optics. One has the coherent states and the squeezed states. Is all of this unified, or in each domain of application does one in some sense use a different representation and mapping between the the real physical system and our calculational tools?
On the other hand, accelerator physics was never such a well defined concept. It is well defined from the sense that it is a collection of all the physics one may need in analyzing, building, designing or improving a particle accelerator. But its a rather mixed bag of classical mechanics, relativity, electricity and magnetism, and material science.
On to radiation, one has Maxwell's equations describing the evolution of electric and magnetic fields. However, one often represents light via a complex scalar field, or via a Wigner function, when coherence properties are required. Currently I'm trying to understand all this terminology related to Fourier Optics. One has a point spread function. One has an optical transfer function. One has an amplitude transfer function. Does one gain something new with these different representations? With the Wigner function, there's a partial interpretation in terms of the distribution of photons. But, being sometimes negative, its not such a clear interpretation. There are operator representations for quantum optics. One has the coherent states and the squeezed states. Is all of this unified, or in each domain of application does one in some sense use a different representation and mapping between the the real physical system and our calculational tools?
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