I guess in my mind there is a practical component and a philosophical one; I've been arguing from a purely philosophical viewpoint: anyone who makes a physical, falsifiable claim is treading in the domain of science. However, I agree with you that there is a practical issue at hand: as a scientist, is it worth my time and energy to debunk supernatural claims if those making the claims will always try and wiggle out of any results refuting their beliefs. That's a tough call and I think it depends on the claim, how much the results matter, and how much impact it will have. One must choose battles carefully. For most religious claims, I think I agree with you: it is frequently rather futile and a waste of time. But not always. What about so-called "creation science" (really a religious dogma in disguise)? Are we as scientists (and citizens) supposed to just sit around while absurd claims about the way the world works are integrated casually into classrooms simply because it is beneath us to refute such obviously crazy ideas? There could be a heavy price to pay for ignoring such a responsibility.
If you're making a reference to the Book of Mormon, I feel that I must contradict you. There is nothing in the book of Mormon that indicates, one way or the other, the existence of dinosaurs. In addition, the book of mormon starts (chronologically speaking) around 600 BC, which is well after the time of dinosaurs. Check your facts before you post, anonymous coward!
Perhaps there are no dinosaurs mentioned by name but there are dragons, satyrs, cockatrice, and least we for get the very easily visualized cureloms and cumoms. Not to mention a menagerie of generic monsters and beasts. With all due respect, I'd say the mormons pretty much nailed it.
Religion and science have nothing to do with each other and anyone who even suggests that is making a grave mistake and fool out him/herself and the science s/he studies.
I get the sense I misinterpreted the main message of your last statement. Based on the context of your post, I believe you are saying culturally and politically science and religion have nothing to do with each other. In this sense, I agree: religion and science are basically culturally orthogonal.
However, one must be careful not to overstate the point with this non-overlapping Magisteria cartoon. Tacitly and overtly, religion makes many claims about the way the world works physically. When this happens, like it or not, religion is treading in the domain of science. There is an afterlife, or there isn't. Either someone rose from the dead, or didn't. Someone turned water into wine, or didn't. Created the world in 7 days, or didn't. Born of a virgin, or wasn't. And so on. If these things happened, then there had to be a mechanism. These claims are not just symbolic abstractions for most believers but real physical claims about the way the universe works at its most fundamental level. Science has a lot to say about the physical possibilities of these claims (usually not siding with the original claim). If religion were to stick to only unfalsifiable, untestable, unphysical claims, then non-overlapping Magisteria works fine.
One has to be careful not to mistake "arbitrary" for "random." What they are doing is randomizing elements of systematic security, not promoting arbitrary security. That is, they are still sending trained patrols, K9 units, inspectors, etc. but randomizing the time, location, and duration. This seems quite smart to me. The irony is that a huge fraction of airport security today IS arbitrary, but NOT random: everyone must stand in line, take off shoes, pack liquids a certain way, scan their laptops, scan luggage, etc. This creates a dangerous situation: a reliable pattern of huge localized gluts of irritable people in a state of chaos while security is focusing on all the wrong sorts of details. It is a reactionary security method of questionable effectiveness (one guy six years ago attempts to blow up a plane with a shoe bomb so now everyone must take off their shoes). Indeed, the current method may be creating a larger security threat while trying to generate a "perception of security." For example, what if someone did have a bomb or gun in their carry-on? Do your really want to have them surrounded by 500+ edgy people (with no shoes on) being pushed through one-way security gates? Perhaps this randomizing element discussed in the article will be a first step toward leading the system to smarter, more effective, and streamlined airport security methods.
I think you are onto something. In the US, having a Ph.D. in scientific fields like physics, chemistry, etc. is really the only way you have a chance of doing cutting edge work in those areas. However, in engineering, unless you would like to be a professor (a good lifestyle, but not for everyone), there is really no reason to get an advanced degree. The BS alone is usually your ticket to the good stuff, assuming you hook up with the right company or firm. Also, as you said, the pay scales don't increase rapidly enough per degree to make the time and energy worth it for most. In other countries, these assumptions may be different. For example: they may have more rapid pay increases per degree and a higher threshold of education to get to the good engineering bits. In addition, US advanced degree programs in most fields are quite excellent and carry some worldwide prestige (although you wouldn't necessarily want to brag about getting a high school degree in the US).
You raise a good point. If it were "exactly" 5ms I would be suspicious. But I'm guessing the article is just reporting 5ms as an approximation. The real issue is that the signal is very short in duration. A supernova, which has comparable energy, is something that lasts minutes. A pulse on the order of ms is not only difficult to measure (for astro people) it is also not easily explained physically.
For instance when running a computation it effectively has a temperature of ~10^9 Kelvin, which is considerably hotter than any known material could withstand.
The quark gluon plasma created at RHIC (and soon at the LHC) is hovering at about 10^12 Kelvin (granted for about 10^(-23) seconds)...So there's one material anyway...
As a physics professor, I often find myself asking the same kind of question. Sadly, I'm way behind you with your tablet and wireless projector, but you are definitely inspiring me with that kind of gear. Here are a few ideas:
I try to use Mythbusters sub-episodes every so often as teaching tools. As most of us know, it's pretty entertaining and, while a little too seat-of-your-pants to serve as rigorous science, it definitely captures the scientific spirit and frequently inspires teachers and students alike. We'll typically watch some part of an episode, discuss the principles involved in the myth, and try and do some calculation related to the episode (e.g. number of ping pong balls to lift a boat off the bottom of the bay, terminal velocity of a penny, etc.). With your setup, you can nicely embed the parts of the video into a presentation then use the tablet to lead a real-time discussion of various topics of interest. As you probably know, there are many nice physics videos out there which can be used in this way. I also can suggest using a nice plotting calculator with your setup to quickly demonstrate ideas like Taylor expansion, Fourier decomposition, basic plotting, etc.
There is some software available out there that will analyze video motion using basic mechanics tools (CM motion, rotational motion, vectors, motion diagrams, position versus time, etc.). You give it a few anchor points on the real video capture and can step it through the motion but with all the vectors and graphs superimposed. Although it is a cool idea, sadly, the version I tried was old quite clumsy (made more clumsy by the laptop/AV setup). However, with your tablet and wireless, you may have more versatility if updated software exists.
There are several intriguing student grading/evaluation systems out there that use bar codes (for example, here). I know at a glance this sounds rather sinister and 1984-ish, but with student-customized bar codes (not tattooed on their foreheads, but rather printed on their papers), I think this can be used quite well to facilitate quick grading of quizzes with real-time feedback and histograms, class participation credit, and other creative classroom data organizing solutions. This could be made especially effective with the mobility provided by your tablet and wireless.
I totally agree with your point 3) as well as the last sentence. Because the arXiv is not peer reviewed, Slashdot should avoid promoting random papers from there. Even a peer reviewed paper needs to be digested by the community before getting widespread public "Eureka!" attention. There are enough amazing confrimed discoveries to discuss without tinkering around the corners of the arXiv.
However, points 1) and 2) aren't particularly relevant. Come on. It isn't like he's a banker trying to write a scientific paper in a field totally orthogonal to his expertise. An interested, informed high energy physicist is certainly qualified to do the kind of analysis in the paper as presented. Granted, it doesn't mean the analysis is correct, but he is generally qualified to approach the problem -- and frequently interesting things can be learned when problems are approached by someone in a different subfield. What you say in point 2) is worse than ad hominem, its unscientific. You can't judge the merits of a new idea or observation based only on an author's past citation record. Science is a claim assessment tool, not a citation index. New ideas and observations, especially if testable, interesting, and presented responsibly, should be examined on their own merits using the scientific process.
Borexino is really an amazing detector, but has a complex history. The experiment is located at an impressive place called the Gran Sasso National Laboratory (LNGS) in Italy. Technically, it is one of the deepest labs in the world as measured by overburdon -- i.e. it has about a kilometer of rock in every direction to shield cosmic rays-- but is actually located high up in the mountains. Interestingly, it is almost directly under where Mussolini was held prisoner and subsequently rescued by German commandos at Campo Imperatore in 1943. It is also near where the movie Ladyhawke was filmed. Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water. The leak was an honest mistake and was actually rather minor as chemical spills go, but it caused a public relations debacle which tangled up the lab and, in particular, Borexino, in a long bureaucratic nightmare. I'm happy to see they are now back in the game producing cutting-edge results.
It should be noted that voids are not uncommon, but the one in the article is about 10 times wider than a typical (named) void on that last scale. In fact, it would fill the entire last picture. This is one big stretch of nothing on the trans-supercluster highway.
All of this contributes to why Fermi's Paradox should be considered Fermi's Blunder by anyone who really thinks this through.
Fermi's Blunder? Hmm. A bit overstated don't you think? Fermi's Overestimation maybe. You might want to read up on Fermi's Paradox. The observations you made have been debated in detail over the past 57 years. Whatever you want to call it, even with the things you mentioned, it isn't an easy effect to simply dismiss out of hand.
I worked with John on the STAR experiment at RHIC in the pion interferometry group. Your description of him as a physics hacker (in a good way) is right on. I do sometimes wonder about his sanity when I read about his latest projects (e.g. see TFA) -- but he is by no means a crank or crackpot. Oddly enough, he also does dog shows as an owner. His personality would fit right into Christopher Guest's movie Best in Show (I also mean that in a good way). So think of him as a dog trainer/quantum mechanic/science fiction author. He's basically a nerd renaissance man.
I think one of the things people forget about "quantum interpretations" is that they are just that: interpretations. The physics is self contained within the mathematics and procedures of quantum theory and its ability to predict experimental outcomes -- and is independent of interpretation. Also, a valid interpretation is inherently subjective, experimentally indistinguishable from another self-consistent interpretation. If new physics actually emerges from a specific interpretation or one interpretation is somehow experimentally distinguishable from another, then you aren't really talking about interpretations anymore and you are talking about some structural, scientific part of the theory. There are perhaps a dozen or more self-consistent interpretations of quantum mechanics on the market, most of them dating back over 40 years, all of them (apparently) experimentally indistinguishable. Some are downright silly, for example, the Copenhagen interpretation, while others tickle the imagination like Many Worlds. Fads will come and go which favor one over another. But despite what people like to believe, there is no experimental way (yet?!) to distinguish between Copenhagen and Many Worlds interpretations. Perhaps one charismatic theorists pushes for one for a few years or the community adopts it as a default for a while, for no other reason than fashion. But the actual science that is done with quantum mechanics marches on independent of all that. The interpretations serve basically three roles: 1) it lets a physicist adopt something so they can sleep at night; 2) one interpretation may provide problem solving insight into new or old problems, which might give it an creative advantage for inventing new ideas; 3) perhaps what you are dealing with isn't an interpretation at all, but rather something fundamental (and thus experimentally distinguishable from other interpretations) and so exploring all its possibilities is natural (hedging your bet in case the theory can be augmented). I personally enjoy thinking about the various quantum interpretations out there, so I certainly don't want to discourage people who like to dabble. What I don't like is when people (especially physicists like myself) start talking about how "the world really is" through these interpretations or speak of them as if they were accepted facts of reality or experimentally confirmed physics, which is certainly not the case for MWI, for example. What we have is basically a powerful engine for calculating things, but the physical meaning of the engine can be viewed many ways and still function as the same engine. To ask what the engine is "really" doing becomes metaphysics because all you can apparently actually measure are the inputs and outputs.
Don't get me wrong, I don't have a problem with giving a nod to ancient human engineering achievements. But why this legacy fixation with finding exactly 7 new ones? On a particularly irritating note, Christ the Redeemer statue was opened in 1931, hardly a wonder of the ancient world.
This "exact amount of caffeine in soda" business is cute. But if I need X grams of caffeine per day to function by noon and through the night, I'm certainly not going to rely on approximate values listed in consumer tables. I just dose on No-Doze and the generic equivalents. There are 200 mg of caffeine per pill and four or five of those a day, spaced at appropriate intervals, keeps me happy, alert, and productive. Also, no more constant trips to the restroom. Besides, the method is cost effective and avoids excessive sugar (or aspartame) intake! A bottle of 90 tablets costs as much as about 5 coffees or large sodas. It also gives me more control over the amount going into my system, in case I want to reduce, enhance, or quit without nasty withdrawal side effects. Sure, I sound chipper now. But I'm sure I'll have to join some caffeine addicts program at some point -- for now this method serves me well...
I always liked the pilot wave idea. Too bad it never got a lot of traction. Is that it is fairly easy to get a neat visual for something like the double slit experiment with this extra classical field and, in that context, it seems to give a lot of insight into how to interpret various curious aspets of quantum mechanics. But when you try to do any other sort of calculation with it (spin states, hydrogen spetra, bound states, scattering, multiparticle stuff) the pilot wave idea just becomes quite murky and intractable.
You are definitely asking all the right questions, TrekkieGod. I'm not really sure I can completely address you concerns, but here are a few ways of thinking about the issues that might help illuminate some things.
Probability as an intrinsic property of an object in nature IS a rather unnerving idea. Quantum mechanics implies that, at its core, nature is not like playing poker where all possible configurations of a hand can be completely mapped out (defining all possible states of the system) and all cards have well-defined values for all time for a given game. In poker, the randomness comes in the shuffle but one could "in principle" track the dynamics of each individual card as a deck is shuffled and dealt, allowing you to know exactly the outcome of each game. It is only in the lack of knowledge of the complex details of the shuffle that makes the game appear random. A similar idea applies when rolling dice. For a realistic die throw, the dynamics of the bounces and rolling is so complicated and hypersensitive to the initial conditions, it is simply impractical to predict the outcome, even if it could be computed in some ideal world. These are cases of "hidden variables." That is, there are parameters in the system you could know in principle, but, either practically or otherwise, you just don't happen to know what their values are. This is not the case in quantum mechanics, where the best you can do is essentially calculate how the probability distributions themselves change and distort in time, and specific outcomes of individual trials are not generally calculable. But unlike a poker game, the quantum mechanical probability distributions themselves don't appear to arise from some hidden variables that could be known even in principle. They seem to be fundamental to nature.
As you implied, this has bizarre implications for the behavior of individual particles (which have been carefully studied over the years). The double slit experiment you mentioned is a great way to highlight the issue. A photon is an indivisible clump of energy of the electromagnetic field. This object can be localized like a classical particle or it can be spread out like a wave, but it interacts like a single object, and its energy is measured all-or-nothing. In this sense, a photon is a "quanta" of an EM field, not a particle in the usual way we think of it (it is frequently called a "particle" by everyone all the time, including myself, but the term is misleading). In the single photon double slit setup, you have a "light cannon" source that somehow releases a single clump of EM energy at a well defined wavelength/color whose momentum is pointed in some convenient direction towards a distant double slit whose separation is on the order of the wavelength. On the other side of the slits you have a distant screen that is designed to measure the location of the photon by absorbing its energy in some irreversible way. If a single photon was "just a wave," you would expect to see (for each photon) a very, very faint double slit interference pattern at the screen that would get gradually brighter as you increased the rate of fire of your source. This is the kind of thing you expect from any wave. If you sent a sine wave of water towards a double slit "breakwater" (imagine yourself in a helicopter hovering above it), you would see wave structure in 2D all though the water that would impinge on a distant beach with a height that looks like a double slit interference pattern. As you decreased the height of the incoming wave, the height of wave on the distant beach would scale down accordingly. But what is seen for a single photon is much stranger. Each individual photon fired from the source leaves a SINGLE localized pock mark on the screen where it hit. The initial location of the first few photons seems essentially random and no obvious interference pattern is present. But as each subsequent photon is fired, over time, an interference pattern "builds up" from the statistical collection of individual poc
You are basically right on (IAAP). Here's my two cents into the thread:
There are are lots of different ways to understand the Heisenberg Uncertainty Principle physically -- most of them not very satisfying without acclimating to the lingo and concepts of quantum theory. Nevertheless, I think one can gain an intellectual foothold into the idea, before even digging into the quantum theory, by realizing that ALL wave behavior (sound, water, radio, light, etc.) obeys something akin to a HUP. If you can get the basic idea down for sound or water waves, then you can start to build a conceptual bridge to matter waves. Since you are an EE, the conceptual underpinnings will probably look quite familiar.
Lots of mathematical qualifications aside, basically ALL waveforms can be represented by a sum of harmonic waves (pure sine and cosine functions). A single pure sine or cosine has a well defined frequency, wavelength, and wave velocity. However, in contrast, an arbitrary waveform does NOT have a single wavelength or frequency -- it has many, given by the distribution of sines and cosines that were used to construct it. A handy variable to use is called the wavenumber, which is basically the number of cycles per meter (proportional to 1/wavelength) of a harmonic wave. An interesting thing to do is plot a particular waveform, say a snapshot of a water wave shaped like a lump at a moment in time, and then also plot the distribution of wavenumbers from all the sines and cosines making up that lump. They are two representations of the same object. One looks like a water lump in space, and the other will look like another lump telling you the distribution of sines and cosines in "wavenumber space." What you find is that if your water lump in space is narrow, then it takes many sines and cosines of many wavenumbers to make that happen. If the water lump is very spread out, you only need a narrow range of wavenumbers of harmonic waves to make this happen. Many engineers are very familiar with this bandwidth effect in the context of transmission theory, but the same will be true for ANY waveform. It is a byproduct of wave theory: the width of the spatial distribution of an arbitrary wave is inversely related to the width of its wavenumber distribution. If you allow the wave to change in time, you get a similar inverse relation for the distribution of the wave in time and the distribution of frequencies in the wave. You are probably familiar with all that in the context of Fourier analysis etc. One says that wavenumber and position are "complimentary" (so are frequency and time).
The big leap in quantum mechanics is that the momentum of a particle is inversely related to the wavelength of some harmonic wave "associated with" the particle. The larger the momentum, the shorter the wavelength of the matter wave and vice versa. That is, momentum and position are complimentary variables. Keep in mind, the wave isn't the particle itself but rather tells you where the particle is likely to be. Once you accept the rather odd idea that momentum and wavelength are inversely related, *wave theory alone* tells you that the more likely a particle is to be at a particular location in space, the wider its distribution of wavenumbers is -- and thus the wider range of momenta it can have. Similarly, if you have a very narrow range of wavenumbers, the wider the spatial extent of the matter wave -- thus for a well defined momentum the particle has a wider range of spatial positions available to it. This is basically the heart of the Heisenberg Uncertainty Principle.
Since this matter wave tells you about probabilities, you need to prepare an ensemble of identical objects and do a statistical analysis of their positions and momenta to see the effect of the HUP. For example, lets say you prepare 100 particles each with a well defined position. Now you perform a position measurement followed by a momentum measurement for each particle. Taking your raw data, you made a plot of the number
Isn't it sufficient enough for these science types to believe in god because it is a "safe bet?" Seriously though, pascal's wager almost always leads to some interesting conversation with Christians and atheists alike. Try supporting it around these types of people if you haven't yet.
Any god who demands blind worship in exchange for eternal salvation is probably not the god one thought one was worshiping. Besides, since when is extortion a good basis for assessing truth? Just because one makes a decision to believe in god under perceived duress doesn't make it a true assertion...
Many other posters have used some variation of "some rich asshole" as a metaphor for the murky, selfish, shadowy figure in the background buying his way into something he didn't earn, driving this gold farming racket. As a general principle, I can see why this might be a problem. But I take issue with the word "rich" in this context. Let's keep in mind that WoW itself costs something on the order of $12-14 per month, not to mention the first 20-50 bucks you paid for the box itself (plus owing a computer at all, plus having some broadband connection...). In comparison, a one time 100g purchase might cost roughly $20, a relatively small fraction of playing the game for one year and a modest amount of one-time absolute money, even by student Slashdotter standards. So one certainly need not be "rich" to buy into this gold farming thing. One might argue, however, that even having the luxury to play the game at all (measured in dollars and time) might already tag you in fairly privileged class on a worldwide scale.
What really happens is that velocities don't add like that. They seem to for everyday objects, but relativistic effects become important at 0.7c.
Your post is right on. I might add that when relativistic effects become important for everyday objects might be a matter of application. For example, some GPS systems need to account for relativistic effects for the relativive motion of objects in orbit with respect to the surface of the earth (moving much smaller than 0.7c). It depends on the accuracy required.
Slashdot Mirror
I guess in my mind there is a practical component and a philosophical one; I've been arguing from a purely philosophical viewpoint: anyone who makes a physical, falsifiable claim is treading in the domain of science. However, I agree with you that there is a practical issue at hand: as a scientist, is it worth my time and energy to debunk supernatural claims if those making the claims will always try and wiggle out of any results refuting their beliefs. That's a tough call and I think it depends on the claim, how much the results matter, and how much impact it will have. One must choose battles carefully. For most religious claims, I think I agree with you: it is frequently rather futile and a waste of time. But not always. What about so-called "creation science" (really a religious dogma in disguise)? Are we as scientists (and citizens) supposed to just sit around while absurd claims about the way the world works are integrated casually into classrooms simply because it is beneath us to refute such obviously crazy ideas? There could be a heavy price to pay for ignoring such a responsibility.
Perhaps there are no dinosaurs mentioned by name but there are dragons, satyrs, cockatrice, and least we for get the very easily visualized cureloms and cumoms. Not to mention a menagerie of generic monsters and beasts. With all due respect, I'd say the mormons pretty much nailed it.
I get the sense I misinterpreted the main message of your last statement. Based on the context of your post, I believe you are saying culturally and politically science and religion have nothing to do with each other. In this sense, I agree: religion and science are basically culturally orthogonal.
However, one must be careful not to overstate the point with this non-overlapping Magisteria cartoon. Tacitly and overtly, religion makes many claims about the way the world works physically. When this happens, like it or not, religion is treading in the domain of science. There is an afterlife, or there isn't. Either someone rose from the dead, or didn't. Someone turned water into wine, or didn't. Created the world in 7 days, or didn't. Born of a virgin, or wasn't. And so on. If these things happened, then there had to be a mechanism. These claims are not just symbolic abstractions for most believers but real physical claims about the way the universe works at its most fundamental level. Science has a lot to say about the physical possibilities of these claims (usually not siding with the original claim). If religion were to stick to only unfalsifiable, untestable, unphysical claims, then non-overlapping Magisteria works fine.
One has to be careful not to mistake "arbitrary" for "random." What they are doing is randomizing elements of systematic security, not promoting arbitrary security. That is, they are still sending trained patrols, K9 units, inspectors, etc. but randomizing the time, location, and duration. This seems quite smart to me. The irony is that a huge fraction of airport security today IS arbitrary, but NOT random: everyone must stand in line, take off shoes, pack liquids a certain way, scan their laptops, scan luggage, etc. This creates a dangerous situation: a reliable pattern of huge localized gluts of irritable people in a state of chaos while security is focusing on all the wrong sorts of details. It is a reactionary security method of questionable effectiveness (one guy six years ago attempts to blow up a plane with a shoe bomb so now everyone must take off their shoes). Indeed, the current method may be creating a larger security threat while trying to generate a "perception of security." For example, what if someone did have a bomb or gun in their carry-on? Do your really want to have them surrounded by 500+ edgy people (with no shoes on) being pushed through one-way security gates? Perhaps this randomizing element discussed in the article will be a first step toward leading the system to smarter, more effective, and streamlined airport security methods.
I think you are onto something. In the US, having a Ph.D. in scientific fields like physics, chemistry, etc. is really the only way you have a chance of doing cutting edge work in those areas. However, in engineering, unless you would like to be a professor (a good lifestyle, but not for everyone), there is really no reason to get an advanced degree. The BS alone is usually your ticket to the good stuff, assuming you hook up with the right company or firm. Also, as you said, the pay scales don't increase rapidly enough per degree to make the time and energy worth it for most. In other countries, these assumptions may be different. For example: they may have more rapid pay increases per degree and a higher threshold of education to get to the good engineering bits. In addition, US advanced degree programs in most fields are quite excellent and carry some worldwide prestige (although you wouldn't necessarily want to brag about getting a high school degree in the US).
You raise a good point. If it were "exactly" 5ms I would be suspicious. But I'm guessing the article is just reporting 5ms as an approximation. The real issue is that the signal is very short in duration. A supernova, which has comparable energy, is something that lasts minutes. A pulse on the order of ms is not only difficult to measure (for astro people) it is also not easily explained physically.
Damn! I just vanished in a puff of logic.
The quark gluon plasma created at RHIC (and soon at the LHC) is hovering at about 10^12 Kelvin (granted for about 10^(-23) seconds)...So there's one material anyway...
Nice post. Thanks for that article.
I try to use Mythbusters sub-episodes every so often as teaching tools. As most of us know, it's pretty entertaining and, while a little too seat-of-your-pants to serve as rigorous science, it definitely captures the scientific spirit and frequently inspires teachers and students alike. We'll typically watch some part of an episode, discuss the principles involved in the myth, and try and do some calculation related to the episode (e.g. number of ping pong balls to lift a boat off the bottom of the bay, terminal velocity of a penny, etc.). With your setup, you can nicely embed the parts of the video into a presentation then use the tablet to lead a real-time discussion of various topics of interest. As you probably know, there are many nice physics videos out there which can be used in this way. I also can suggest using a nice plotting calculator with your setup to quickly demonstrate ideas like Taylor expansion, Fourier decomposition, basic plotting, etc.
There is some software available out there that will analyze video motion using basic mechanics tools (CM motion, rotational motion, vectors, motion diagrams, position versus time, etc.). You give it a few anchor points on the real video capture and can step it through the motion but with all the vectors and graphs superimposed. Although it is a cool idea, sadly, the version I tried was old quite clumsy (made more clumsy by the laptop/AV setup). However, with your tablet and wireless, you may have more versatility if updated software exists.
There are several intriguing student grading/evaluation systems out there that use bar codes (for example, here). I know at a glance this sounds rather sinister and 1984-ish, but with student-customized bar codes (not tattooed on their foreheads, but rather printed on their papers), I think this can be used quite well to facilitate quick grading of quizzes with real-time feedback and histograms, class participation credit, and other creative classroom data organizing solutions. This could be made especially effective with the mobility provided by your tablet and wireless.
Anyway, all the best with your pending projects.
However, points 1) and 2) aren't particularly relevant. Come on. It isn't like he's a banker trying to write a scientific paper in a field totally orthogonal to his expertise. An interested, informed high energy physicist is certainly qualified to do the kind of analysis in the paper as presented. Granted, it doesn't mean the analysis is correct, but he is generally qualified to approach the problem -- and frequently interesting things can be learned when problems are approached by someone in a different subfield. What you say in point 2) is worse than ad hominem, its unscientific. You can't judge the merits of a new idea or observation based only on an author's past citation record. Science is a claim assessment tool, not a citation index. New ideas and observations, especially if testable, interesting, and presented responsibly, should be examined on their own merits using the scientific process.
Borexino is really an amazing detector, but has a complex history. The experiment is located at an impressive place called the Gran Sasso National Laboratory (LNGS) in Italy. Technically, it is one of the deepest labs in the world as measured by overburdon -- i.e. it has about a kilometer of rock in every direction to shield cosmic rays-- but is actually located high up in the mountains. Interestingly, it is almost directly under where Mussolini was held prisoner and subsequently rescued by German commandos at Campo Imperatore in 1943. It is also near where the movie Ladyhawke was filmed. Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water. The leak was an honest mistake and was actually rather minor as chemical spills go, but it caused a public relations debacle which tangled up the lab and, in particular, Borexino, in a long bureaucratic nightmare. I'm happy to see they are now back in the game producing cutting-edge results.
Pictures of the void would be somewhat awkward. But the following outline might give one a sense of scale for the size of this frickin' non-thing.
Our galaxy: about 100000 ly across
Our Local Group of galaxies: about 10 million ly across
The Virgo Supercluster (Local Group is in it): about 200 million ly across
A bunch of superclusters near the Virgo Supercluster : about 1 billion ly across in picture.
It should be noted that voids are not uncommon, but the one in the article is about 10 times wider than a typical (named) void on that last scale. In fact, it would fill the entire last picture. This is one big stretch of nothing on the trans-supercluster highway.
Fermi's Blunder? Hmm. A bit overstated don't you think? Fermi's Overestimation maybe. You might want to read up on Fermi's Paradox. The observations you made have been debated in detail over the past 57 years. Whatever you want to call it, even with the things you mentioned, it isn't an easy effect to simply dismiss out of hand.
I worked with John on the STAR experiment at RHIC in the pion interferometry group. Your description of him as a physics hacker (in a good way) is right on. I do sometimes wonder about his sanity when I read about his latest projects (e.g. see TFA) -- but he is by no means a crank or crackpot. Oddly enough, he also does dog shows as an owner. His personality would fit right into Christopher Guest's movie Best in Show (I also mean that in a good way). So think of him as a dog trainer/quantum mechanic/science fiction author. He's basically a nerd renaissance man.
I think one of the things people forget about "quantum interpretations" is that they are just that: interpretations. The physics is self contained within the mathematics and procedures of quantum theory and its ability to predict experimental outcomes -- and is independent of interpretation. Also, a valid interpretation is inherently subjective, experimentally indistinguishable from another self-consistent interpretation. If new physics actually emerges from a specific interpretation or one interpretation is somehow experimentally distinguishable from another, then you aren't really talking about interpretations anymore and you are talking about some structural, scientific part of the theory. There are perhaps a dozen or more self-consistent interpretations of quantum mechanics on the market, most of them dating back over 40 years, all of them (apparently) experimentally indistinguishable. Some are downright silly, for example, the Copenhagen interpretation, while others tickle the imagination like Many Worlds. Fads will come and go which favor one over another. But despite what people like to believe, there is no experimental way (yet?!) to distinguish between Copenhagen and Many Worlds interpretations. Perhaps one charismatic theorists pushes for one for a few years or the community adopts it as a default for a while, for no other reason than fashion. But the actual science that is done with quantum mechanics marches on independent of all that. The interpretations serve basically three roles: 1) it lets a physicist adopt something so they can sleep at night; 2) one interpretation may provide problem solving insight into new or old problems, which might give it an creative advantage for inventing new ideas; 3) perhaps what you are dealing with isn't an interpretation at all, but rather something fundamental (and thus experimentally distinguishable from other interpretations) and so exploring all its possibilities is natural (hedging your bet in case the theory can be augmented). I personally enjoy thinking about the various quantum interpretations out there, so I certainly don't want to discourage people who like to dabble. What I don't like is when people (especially physicists like myself) start talking about how "the world really is" through these interpretations or speak of them as if they were accepted facts of reality or experimentally confirmed physics, which is certainly not the case for MWI, for example. What we have is basically a powerful engine for calculating things, but the physical meaning of the engine can be viewed many ways and still function as the same engine. To ask what the engine is "really" doing becomes metaphysics because all you can apparently actually measure are the inputs and outputs.
Don't get me wrong, I don't have a problem with giving a nod to ancient human engineering achievements. But why this legacy fixation with finding exactly 7 new ones? On a particularly irritating note, Christ the Redeemer statue was opened in 1931, hardly a wonder of the ancient world.
This "exact amount of caffeine in soda" business is cute. But if I need X grams of caffeine per day to function by noon and through the night, I'm certainly not going to rely on approximate values listed in consumer tables. I just dose on No-Doze and the generic equivalents. There are 200 mg of caffeine per pill and four or five of those a day, spaced at appropriate intervals, keeps me happy, alert, and productive. Also, no more constant trips to the restroom. Besides, the method is cost effective and avoids excessive sugar (or aspartame) intake! A bottle of 90 tablets costs as much as about 5 coffees or large sodas. It also gives me more control over the amount going into my system, in case I want to reduce, enhance, or quit without nasty withdrawal side effects. Sure, I sound chipper now. But I'm sure I'll have to join some caffeine addicts program at some point -- for now this method serves me well...
I always liked the pilot wave idea. Too bad it never got a lot of traction. Is that it is fairly easy to get a neat visual for something like the double slit experiment with this extra classical field and, in that context, it seems to give a lot of insight into how to interpret various curious aspets of quantum mechanics. But when you try to do any other sort of calculation with it (spin states, hydrogen spetra, bound states, scattering, multiparticle stuff) the pilot wave idea just becomes quite murky and intractable.
Probability as an intrinsic property of an object in nature IS a rather unnerving idea. Quantum mechanics implies that, at its core, nature is not like playing poker where all possible configurations of a hand can be completely mapped out (defining all possible states of the system) and all cards have well-defined values for all time for a given game. In poker, the randomness comes in the shuffle but one could "in principle" track the dynamics of each individual card as a deck is shuffled and dealt, allowing you to know exactly the outcome of each game. It is only in the lack of knowledge of the complex details of the shuffle that makes the game appear random. A similar idea applies when rolling dice. For a realistic die throw, the dynamics of the bounces and rolling is so complicated and hypersensitive to the initial conditions, it is simply impractical to predict the outcome, even if it could be computed in some ideal world. These are cases of "hidden variables." That is, there are parameters in the system you could know in principle, but, either practically or otherwise, you just don't happen to know what their values are. This is not the case in quantum mechanics, where the best you can do is essentially calculate how the probability distributions themselves change and distort in time, and specific outcomes of individual trials are not generally calculable. But unlike a poker game, the quantum mechanical probability distributions themselves don't appear to arise from some hidden variables that could be known even in principle. They seem to be fundamental to nature.
As you implied, this has bizarre implications for the behavior of individual particles (which have been carefully studied over the years). The double slit experiment you mentioned is a great way to highlight the issue. A photon is an indivisible clump of energy of the electromagnetic field. This object can be localized like a classical particle or it can be spread out like a wave, but it interacts like a single object, and its energy is measured all-or-nothing. In this sense, a photon is a "quanta" of an EM field, not a particle in the usual way we think of it (it is frequently called a "particle" by everyone all the time, including myself, but the term is misleading). In the single photon double slit setup, you have a "light cannon" source that somehow releases a single clump of EM energy at a well defined wavelength/color whose momentum is pointed in some convenient direction towards a distant double slit whose separation is on the order of the wavelength. On the other side of the slits you have a distant screen that is designed to measure the location of the photon by absorbing its energy in some irreversible way. If a single photon was "just a wave," you would expect to see (for each photon) a very, very faint double slit interference pattern at the screen that would get gradually brighter as you increased the rate of fire of your source. This is the kind of thing you expect from any wave. If you sent a sine wave of water towards a double slit "breakwater" (imagine yourself in a helicopter hovering above it), you would see wave structure in 2D all though the water that would impinge on a distant beach with a height that looks like a double slit interference pattern. As you decreased the height of the incoming wave, the height of wave on the distant beach would scale down accordingly. But what is seen for a single photon is much stranger. Each individual photon fired from the source leaves a SINGLE localized pock mark on the screen where it hit. The initial location of the first few photons seems essentially random and no obvious interference pattern is present. But as each subsequent photon is fired, over time, an interference pattern "builds up" from the statistical collection of individual poc
There are are lots of different ways to understand the Heisenberg Uncertainty Principle physically -- most of them not very satisfying without acclimating to the lingo and concepts of quantum theory. Nevertheless, I think one can gain an intellectual foothold into the idea, before even digging into the quantum theory, by realizing that ALL wave behavior (sound, water, radio, light, etc.) obeys something akin to a HUP. If you can get the basic idea down for sound or water waves, then you can start to build a conceptual bridge to matter waves. Since you are an EE, the conceptual underpinnings will probably look quite familiar.
Lots of mathematical qualifications aside, basically ALL waveforms can be represented by a sum of harmonic waves (pure sine and cosine functions). A single pure sine or cosine has a well defined frequency, wavelength, and wave velocity. However, in contrast, an arbitrary waveform does NOT have a single wavelength or frequency -- it has many, given by the distribution of sines and cosines that were used to construct it. A handy variable to use is called the wavenumber, which is basically the number of cycles per meter (proportional to 1/wavelength) of a harmonic wave. An interesting thing to do is plot a particular waveform, say a snapshot of a water wave shaped like a lump at a moment in time, and then also plot the distribution of wavenumbers from all the sines and cosines making up that lump. They are two representations of the same object. One looks like a water lump in space, and the other will look like another lump telling you the distribution of sines and cosines in "wavenumber space." What you find is that if your water lump in space is narrow, then it takes many sines and cosines of many wavenumbers to make that happen. If the water lump is very spread out, you only need a narrow range of wavenumbers of harmonic waves to make this happen. Many engineers are very familiar with this bandwidth effect in the context of transmission theory, but the same will be true for ANY waveform. It is a byproduct of wave theory: the width of the spatial distribution of an arbitrary wave is inversely related to the width of its wavenumber distribution. If you allow the wave to change in time, you get a similar inverse relation for the distribution of the wave in time and the distribution of frequencies in the wave. You are probably familiar with all that in the context of Fourier analysis etc. One says that wavenumber and position are "complimentary" (so are frequency and time).
The big leap in quantum mechanics is that the momentum of a particle is inversely related to the wavelength of some harmonic wave "associated with" the particle. The larger the momentum, the shorter the wavelength of the matter wave and vice versa. That is, momentum and position are complimentary variables. Keep in mind, the wave isn't the particle itself but rather tells you where the particle is likely to be. Once you accept the rather odd idea that momentum and wavelength are inversely related, *wave theory alone* tells you that the more likely a particle is to be at a particular location in space, the wider its distribution of wavenumbers is -- and thus the wider range of momenta it can have. Similarly, if you have a very narrow range of wavenumbers, the wider the spatial extent of the matter wave -- thus for a well defined momentum the particle has a wider range of spatial positions available to it. This is basically the heart of the Heisenberg Uncertainty Principle.
Since this matter wave tells you about probabilities, you need to prepare an ensemble of identical objects and do a statistical analysis of their positions and momenta to see the effect of the HUP. For example, lets say you prepare 100 particles each with a well defined position. Now you perform a position measurement followed by a momentum measurement for each particle. Taking your raw data, you made a plot of the number
Sam Harris has an amusing definition of Faith: (paraphrased) "Faith is the permission religious people give each other to deny evidence."
Any god who demands blind worship in exchange for eternal salvation is probably not the god one thought one was worshiping. Besides, since when is extortion a good basis for assessing truth? Just because one makes a decision to believe in god under perceived duress doesn't make it a true assertion...
Many other posters have used some variation of "some rich asshole" as a metaphor for the murky, selfish, shadowy figure in the background buying his way into something he didn't earn, driving this gold farming racket. As a general principle, I can see why this might be a problem. But I take issue with the word "rich" in this context. Let's keep in mind that WoW itself costs something on the order of $12-14 per month, not to mention the first 20-50 bucks you paid for the box itself (plus owing a computer at all, plus having some broadband connection...). In comparison, a one time 100g purchase might cost roughly $20, a relatively small fraction of playing the game for one year and a modest amount of one-time absolute money, even by student Slashdotter standards. So one certainly need not be "rich" to buy into this gold farming thing. One might argue, however, that even having the luxury to play the game at all (measured in dollars and time) might already tag you in fairly privileged class on a worldwide scale.
Your post is right on. I might add that when relativistic effects become important for everyday objects might be a matter of application. For example, some GPS systems need to account for relativistic effects for the relativive motion of objects in orbit with respect to the surface of the earth (moving much smaller than 0.7c). It depends on the accuracy required.
...I wonder how you say "would you like fries with that?" in Latin?