I suppose the examples I can give of my colleagues are mostly in the engineering disciplines. Several are programmers or network administrators. Several are glorified mechanical engineers that were hired because they understand thermodynamic processes. Several went into material science and metallurgy. Many others went into teaching high school and middle school science, which was their original goal.
I wouldn't say I'd use myself as an example simply because I haven't really chosen a career yet. I've worked as a professional concert sound engineer, as a musician, as an electrical engineer (embedded systems), and as a programmer. I've finally decided to try and make a career out of computer science, and perhaps focus on audio software or scientific simulation.
I wouldn't say that physics majors 'have' to get a job doing something else. It's all physics. They're all doing physics in some form or another, just very few go on and do serious high-level research in physics unless they choose to go on and get a Masters or PhD. Does that make those that go on to teach or program any less of a physicist? I would hope not.
As far as why physics isn't publicized as such I honestly don't know. I know the fact is definitely publicized to the physics majors once they are part of a department. I can say that I would hope that it is not publicized as such, because I think that the types of people that go into physics are the ones that do it because they truly enjoy the task of understanding how the universe works at micro and macroscopic levels. They're not nearly as concerned with career at the college level as they are in the pursuit of knowledge, whether practical or arcane (although usually tending toward the bizarre). Most tend to take whatever engineering classes interest them in order to gain some more specific practical knowledge. For example, my college discipline was Photonic Engineering, which was a part of the EE department.
I don't think that physics programs would attract the right kind of people if they were advertising for the engineering departments, and I suppose the engineering departments wouldn't appreciate it much either.
There's a problem with your argument. Speaking as a physicist (who is now studying CS at the graduate level) every single physicist I know is working steadily and happily and is usually the most appreciated individual in their respective workplace.
The problem stems from the assumption that there is a 'physics' industry out there that physicists move into when they graduate from college. I believe I speak for most physicists when I say that very few actually move on to performing high level physics research. Most move from physics directly into the engineering or scientific field that they most enjoy.
This works out rather well in most cases, because intelligent employers understand that a physicist won't be able to perform at 100% of the level of a mechanical engineer, or 100% the level of a chemical engineer, or computer scientist, etc. However, physicists generally have the ability to perform at say, 75% ACROSS all of those fields, making them very versatile in the workplace, and therefore, very appreciated.
So what does your theory say about those of us who are moving from physics to a more serious role in CS?
Disk reliability is highly governed by mechanical failure. Any fruitful attempt to create a more reliable hard drive head design would then logically have to include a reduction of moving parts. Rigid bodies can be secured with far greater precision and tolerance than movable solenoid-driven parts, therefore the goal that is being presented in the granparent's design is one of a 100% stationary head. The only moving part in this system would then be the rotating platters, and the main point of falure would then be the bearing. Fluid bearing and magnetic bearing drives could provide added reliability to those design points, but removing the delicate moving head assembly would have to produce drives with at least an order of magnitude more reliability than current consumer designs.
If the only argument against this is that the magnetic pickup on the head can't be made small enough to place many side by side, I would present the option that the head does not have to cover one linear radius across the platter, but rather each sequential pickup coil could be offset by some angle, thus producing heads spiraling out from the center. This entire head pickup assembly could then be precisely and firmly mounted above the platter and voila!... The most reliable and expensive hard drive ever created.
I dunno about you, but I'd buy one.
And I could imagine a Linux Beowolf cluster of them too...
It's not a different method, it's the same method...
The only difference is if you accidentally route the end you're holding on to THROUGH the center of the cables, those alternating twists tie themselves into a series of half-hitch knots every two twists.
When I was working as a professional sound engineer, I used to have to train stagehands how to coild cables properly. I'd demonstrate, then I'd have them coil theirs and all throw their cables at the same time, side by side.
What I didn't tell them was that I had bets going with the other audio guys as to how many cables would untwist with all those knots in them.
Indeed it is. I wrote a few papers in college about musical psychoacoustics and how bizarre the opposing results of the research turn out to be. This guy, however, is the only source that I've read that shows a truly logical, scientific approach to debunk the audiophile mentality.
I hope that there's enough readers on this thread that actually read the entire paper and can understand it.
It's actually a pretty disgusting trend in professional audio as well.
Manufacturers offer up specifications for their equipment based on the demand for perfectly linear, zero-distortion amplifiers and signal processing equipment. However, all the reviews then go back and say that the sound of a particular distorted source is preferable. At that point, there's really no point in providing a zero-distortion signal chain. Any distortion it produces would be very well masked by the distortion of the source material.
Here is the best source I've read on the subject:
http://www.dself.dsl.pipex.com/ampins/pseudo/sub je ctv.htm#1
Please don't slashdot him, I really would like to be able to offer this link to others in the future.
The parent poster is absolutely correct in that the goal of producing an amplifier is to create a perfectly linear constant multiplication of an input signal. Any non-linearities must be viewed as flaws in the amplifier design, or at least as limits to its practical range of use. The switch to transistor technology happened so rapidly because they have much better characteristics than tube amplifiers.
All the arguments here can be summed up as such. I feel if we keep these points in mind, we can stop arguing.
1) An amplifier by definition is used only to amplify sound. 2) Distortion is a negative byproduct of a poorly designed amplifier. 3) Tubes significantly distort the sound they amplify by adding a certain color of harmonic content dependent on how much the tube is driven -- this is mainly due to NON-linearities in the circuit. 4) Live and recorded music has developed an enormous dependence on signal processing -- both linear and non-linear. Signal processors can do ANYTHING to the sound, be it EQ, delay, distortion, reverberation, etc. 5) Many sound engineers, audiophiles, guitarists, producers, and listeners have developed a distinct liking to the tone color produced by specific applications of tube amplifiers. Many others can't stand the distortion. Still many others can't stand the distortion and yet purchase $10,000 tube amplifiers. I blame fairies too... 6) The individuals that argue for tube amplifiers are actually arguing for their use as a signal processor that is often conveniently attached to an amplifier.
And here's the real kickers that I've learned through years of live sound and recording engineering:
7) Never tell someone what they like and don't like to hear. They will never change their mind. 8) Never confuse amplification with signal processing, whether it's digital (DSP) or analog (tubes, etc). If a device does both, that's great, but realize that it's doing two jobs for you.
As a side note, most DSP doesn't accurately reproduce tube sounds becuase tube distortion is very nonlinear. DSP works well for linear systems because all linear systems have a 'transfer function' that can be used to simulate that system perfectly. Nonlinear systems do not have a constant transfer function, if they have a transfer function at all, and therefore would require an exponential amount of additional processing in order to recreate nonlinear distortion. Of course, there are tricks...
So I would argue that it is not so much "increasing data" but "scientist's increasing faith" that Einstein was right.
Uh oh... He said the "F" word...
I've just spent hours reading all the way to the bottom of these comments. It seems that there are many, many people out there that feel that they are perfectly qualified to analyze the data these satellites will provide. Maybe you are... Maybe you know someone who is... It doesn't really matter.
2 Points:
1) The scientific community is largely based on recognition of accomplishment. You may feel that the taxpayers should get the data, but you'd be acting in haste. You're paying the scientists salaries so that *they* can make important discoveries, not *you*. If you can come up with a genius experiment and design incredibly sophisticated measurement equipment to gather data, then by all means, do it. Then you're called a scientist. However, you're only credible if you can properly analyze that data and present it in a peer-moderated forum. In other words, it's not your experiment. You pay for them to do it, but to suggest that someone else should be able to analyze the data concurrently and take credit for their accomplishments... tsk tsk tsk...
2) Data analysis involves much more than simply plotting theoretical values "against the the data they receive from the gyros". What the non-scientific community doesn't seem to understand is that there is another number associated with data --
-- error.
It's easy to plot out mean values of raw data and compare them to theory. In that case, you're right. There are many, many people out there that would love to determine for themselves if they understand the mathematics of this experiment enough to analyze the data. However, The real experiment is determining to what extent their data can be 'trusted'. In order to do this, they must factor in the sensitivity of *every* piece of equipment used to collect any portion of the data, as well as all of the natural statistical errors that coincide with an experiment of this nature. I would imagine that most of the data collected in experiments of this nature would look like noise to any scientist who did not also have (possibly classified) knowledge of the nature of the instruments being used to collect the data.
Nuclear or quantum physics experiments are notorious for 'conjuring' an amazingly accurate and repeatable value for certain theoretical constants from a set of data points that looks like someone dropped a bag of rice on a piece of graph paper.
Now as far as the drug complaint is concerned, that's an entirely different matter. The scientists aren't looking to make a profit off of their research. Unless by profit you mean future grants and awards that they base their well-being on.
No, you can glamorize musicians all you want. In fact, I'd be willing to bet that most of the top geeks that read Slashdot are fairly accomplished musicians.
Now you can stop glamorizing quite a large number of pop-stars, and I'll be happy.
Well, for one, magnetic fields fall off over distance just like electric fields. Since there is no such thing as a magnetic monopole (at least not that anyone has been able to discover), then magnetic fields have to begin with a dipole field. Additional dipoles put together create quadrapoles and octopoles, etc, which have magnetic fields that fall off all at different rates. This can get complicated...
The point, however, is that the actuator magnets, although very strong, aren't nearly as strong as the read/write heads that are fractions of a millimeter away from the platter.
Now pop down a couple threads to the post about biasing the magnetic field at high frequencies and you just might be confused enough about the topic to actually do a google search on it.
Well, if your reasons for wanting an ultimate desktop is simply to put windows to shame, then you'll be waiting a long time.
The reality is that neither windows, nor KDE, nor Gnome, are an ultimate desktop solution. If you want one of them to become the ultimate desktop, then all you have to do is support that desktop and wait. You can't rush innovation.
In any case, the point of my response was that there will *never* be a single ultimate desktop as long as there are individuals willing to put the time in to develop their own desktop tools. I mean, there's not even an ulitmate *windowing* system for linux yet, so don't expect an ultimate desktop. XFree86 is a standard windowing system, but it's by no means the best and only one.
This manufacturing technique does not utilize the properties of refraction at all. At no point does the author ever try to get the reader to believe that there is any sort of 'lensing' going because of the water. The problem is diffraction -- specifically, the problem of wavelength-limited diffraction. There is a theoretical limit on how small we can focus a beam of light based on the wavelength of that light. By submerging the process underwater, we *slow* the light down, therefore creating an artificially shorter wavelength. It's as if we increased the frequency of the light without having to manufacture more expensive lasers.
Refraction is the effect we see when that slowing of light at a boundary changes the direction of the incident light. However, in these manufacturing cases, the light is perpendicular to the wafer, therefore no refraction will take place. In fact, if refraction does take place, they will have to compensate for it somehow.
>>All the desktop technologies seem doomed to live side by side forever. sigh.
Exactly how it should be. The whole idea behind the development of free software is that if *you* wanted to develop your own desktop software, then anyone can and will be free to use it. There is already a top-down heirarchy in place for the linux desktop. It's called KDE. It's called Gnome. It's called Enlightenment. Each of these desktops are developed in the same manner as the linux kernel. There's a large number of developers working on different little pieces, and there's a maintainer (or core of maintainers) that coordinates all of their efforts and puts together a finished product.
Just because there's choice doesn't mean you have to choose both, just be glad that you have the opportunity to make a choice in the first place. Sure, all those combined efforts may be put to better use working together on the 'ultimate' desktop, but this is a far more efficient way of determining what that 'ultimate' desktop is.
Let's just think of it as a breadth search of all possible desktop environments, and we can later choose the paths that we like the most and combine those ideas into a single desktop environment in the future.
Breakthroughs rarely happen from focused efforts... Breakthroughs happen because an individual has a vision of a far more efficient method and acts upon that to create a new way of doing things.
A windows-like desktop is not even close to a breakthrough, but getting more support for the linux desktop in general will spur more development in the area and may help some individual to come up with a completely new, 'breakthrough' desktop for you.
I'll ride my B.S. in physics in on the coat-tails of the PhD.
It is true that the energy levels we are dealing with are miniscule. However, if they can be heard by your ear, they can be heard by others. There are several ways that sound waves lose intensity -- not energy. The most obvious is dispersion. Sound follows the distance-squared law just like any point-source radiation (we'll ignore that a speaker has area, and is therefore not a point-source. If you really wanna see scary math, I'll show you some area or volume-source sound fields). So if you want the sound to be less intense, easy... Just get further away from it.
The next method of sound reduction is absorption. This is when the sound energy causes something to vibrate, transferring energy into heat. Normally, as in those foam coverings we see on studio walls (or around your headphone earpiece), the sound energy is trapped inside the small pockets of air that make up the foam or fiberglass sound insulation, and simply bounce around inside until the energy eventually gets dispersed into the solid material of the foam itself.
The next method of sound reduction is reflection. Of course, this does nothing to actually get rid of the energy, but rather channels it away in another direction. Remember though, there is no such thing as a perfect reflector. Every reflector will absorb a tiny bit of energy from the source wave.
So the reason you don't hear the output of the headphones if you're not wearing them is because almost all of the sound energy is trapped between the ear and the speaker and simply bounces around in there until it is all either absorbed by the headphone casing or your own flesh. Of course, if you got right up next to the headphones, I'm certain you could hear plenty of sound being generated by the vibration of the headphone casing itself.
What we should all realize about this particular application is that the sound source is almost purely periodic. The only part of the fan noise that can't be predicted is the chaotic sound created by the turbulence of the air at the tips of the fan blades. This means that through some 'simple' correlation techniques, the fan noise can be sampled and an exact cancellation source can be calculated -- for a given listening location. This is unlike the headphones application, which has to deal with computing a large variety of random audible noises. You'll probably notice that the ability of these devices to cancel sound is limited to a certain bandwidth of the middle range of human hearing, and even then only by about 10-15 dB at best. It will work fairly well on the lower frequencies, but will rely almost completely on the mass of the headphone casing itself to block the higher frequencies from reaching your ear.
The most interesting part of this problem from a physicists point of view will be how to get around the doppler effects of sampling and reproducing a waveform in a moving airstream. Also, fans don't produce a steady stream of air -- rather, they produce a pulsing stream of air that varies depending on your location in front of the fan. Any musician that's tried to practice in a room with a ceiling fan will understand that frustration. I suppose that whatever software you use to calculate a cancelling waveform can be used to perform those calculations as well.
Pick a wavelength, find roughly the index of refraction, and you can roughly determine the speed of light in the doped silicon.
I think most people who post questions like this are still missing the point. Distance limitations are determined largely by inefficiencies in power transfer, which are almost irrelevent when dealing with light transmission down a fiber. Basically, once you have the light in a waveguide tuned to that frequency, it doesn't escape except by quirks of quantum mechanics.
So to answer that, it's a question of energy and heat, not about speed.
Photonics has been the 'next big thing' for quite a while now. I even decided to get a degree in photonic engineering. What do I do now? I teach music and run sound at rock concerts...
Photonic engineering (or electro-optics, as us physicists like to call the research side of it), is plagued by the same problems as the rest of the tech industry. Few companies are willing to fund the research in developing manufacturing techniques, therefore the incredible research that has been done in the field will sit in the journals getting dusty (as it has been for the past 10 years).
I will say that this is a big step for the industry though. Not because of Intel's 'breakthrough discovery', but simply because with a big name company making a press release about new photonic computing technology, many other companies will be tempted to scramble into that field as well. Someday down the line, I may actually be able to work in this field simply because of this press release...
Sorry, accidentally posted anonymously the first time:
The limitation on physical distance in an electrical medium is dictated by its impedance, which dissipates the electrical energy in the form of heat. This creates an enormous problem of power loss, which increases linearly with the distance of the transmission line.
An optical waveguide, such as fiber or the silicon waveguides mentioned in the article, see no such losses due to electrical impedance.
Theoretically, as long as the parameters are met for photonic propagation, light will stay in the waveguide indefinitely. However, there are still losses due to imperfections and impurities in the medium itself, caused by microscopic deformities, bubbles, splices in the fiber, etc. There are also some losses dues to quantum effects, which we see in the form of 'evanescent' waves that tunnel outside of the boundaries of the waveguide.
What you really want to be asking is what is the transmissive and absorbtive properties for the silicon medium they use for the particular wavelength(s) of light that they are developing the technology with. If you know that, then combined with the effects above you can get a decent estimate of the power dissipation of the system for a given photon source.
My feeling, without performing the calculations, is that you will be pleasantly surprised at how little energy will be dissipated in the form of heat.
Another point that I haven't seen moderated up to my reading level --
Optical processing works theoretically similar to electronic processing. The main differences are that instead of transferring signal via an electrical field down a conductor, you transfer signal via photons travelling down a waveguide. The advantage that I haen't seen discussed yet is that photons travelling down a waveguide exhibit no resistive losses in the form of heat. In fact, optical processing requires very little current, and thus produces very little heat.
The heat issue is something I think all the readers of this site can appreciate.
In the end, it will all come down to manufacturing costs. If this technology can be manufactured in such a way that it is more cost efficient than semiconductor electronics, then it WILL be the future.
My personal belief is that optical electronics are the only future we can expect. We cannot send any signal faster than the speed of light. With optical circuitry, as stated in a previous post, we are ONLY limited by the speed at which we can gate a source of photons.
Who knows? The technology may progress very soon to the point at which quantum computing -- counting individual photons of light -- may become our ultimate limit of processing speed. How would that change the state of computing? Knowing that there is no possible way to process and transfer data any faster without redefining the laws of relativity???
Our ears are much less 'fooled' than our eyes are. Many of the posts suggest that what is coming out of our sound cards is anything less than a 44.1kHz, stereo, 16 bit audio stream. If you think that somehow your speakers vibrate any differently because the source was encoded as an MP3 you are frightfully mistaken.
The whole point of audio compression is to recreate the original waveform as accurately as possible. I challenge any one of you to a blind A/B test of uncompressed 16 bit CD audio vs. 320 kbit MP3. Encoding with lower bitrates results in a clearly audible distortion. Nothing fooling our ears there. We listen to dstortion all the time. Chances are, unless you have a very nice stereo system, very litle of the original waveform reaches your ear undistorted.
The true irony of this situation is that 90% of the music that people listen to is distorted on purpose. Electric guitars, synthesizers, and basically any compression and EQ processing add unnatural distortion to musical instruments. In fact, noise and distortion are natural artifacts of any musical instrument. If they weren't there, every instrument would end up sounding like it was straight out of a cheap Casio.
This is definitely not a scientific article. There is no experiment, there is no data, there is no experiment, there is no statistical analysis, and there is no explanation of error.
However, if the theory is that there are certain kinds of distortion that can damage hearing at greater than its natural failure rate, THEN we may have something worthy of scientific study.
Musicians listen to the music. Engineers listen to the sound. Audiophiles listen to the noise.
All my music professors (except for the sound design guys) had some pretty crappy stereos at home. They simply had no reason to upgrade because what they have reproduces what they care to hear just fine. Musicians study for years in order to learn how to analyze sound in a completely different manner than the average listener. They're not out to recreate sound, they're trying to recreate the beauty of the musical composition itself.
Well, if you're going the speed of light, you ARE, in fact, light. However, if you're going very, very close to the speed of light, the light coming from your headlights will be constrained to a tight cone projecting in the direction of travel. Sort of a relativistic tunnel vision.
Slashdot Mirror
I suppose the examples I can give of my colleagues are mostly in the engineering disciplines. Several are programmers or network administrators. Several are glorified mechanical engineers that were hired because they understand thermodynamic processes. Several went into material science and metallurgy. Many others went into teaching high school and middle school science, which was their original goal.
I wouldn't say I'd use myself as an example simply because I haven't really chosen a career yet. I've worked as a professional concert sound engineer, as a musician, as an electrical engineer (embedded systems), and as a programmer. I've finally decided to try and make a career out of computer science, and perhaps focus on audio software or scientific simulation.
I wouldn't say that physics majors 'have' to get a job doing something else. It's all physics. They're all doing physics in some form or another, just very few go on and do serious high-level research in physics unless they choose to go on and get a Masters or PhD. Does that make those that go on to teach or program any less of a physicist? I would hope not.
As far as why physics isn't publicized as such I honestly don't know. I know the fact is definitely publicized to the physics majors once they are part of a department. I can say that I would hope that it is not publicized as such, because I think that the types of people that go into physics are the ones that do it because they truly enjoy the task of understanding how the universe works at micro and macroscopic levels. They're not nearly as concerned with career at the college level as they are in the pursuit of knowledge, whether practical or arcane (although usually tending toward the bizarre). Most tend to take whatever engineering classes interest them in order to gain some more specific practical knowledge. For example, my college discipline was Photonic Engineering, which was a part of the EE department.
I don't think that physics programs would attract the right kind of people if they were advertising for the engineering departments, and I suppose the engineering departments wouldn't appreciate it much either.
There's a problem with your argument. Speaking as a physicist (who is now studying CS at the graduate level) every single physicist I know is working steadily and happily and is usually the most appreciated individual in their respective workplace.
The problem stems from the assumption that there is a 'physics' industry out there that physicists move into when they graduate from college. I believe I speak for most physicists when I say that very few actually move on to performing high level physics research. Most move from physics directly into the engineering or scientific field that they most enjoy.
This works out rather well in most cases, because intelligent employers understand that a physicist won't be able to perform at 100% of the level of a mechanical engineer, or 100% the level of a chemical engineer, or computer scientist, etc. However, physicists generally have the ability to perform at say, 75% ACROSS all of those fields, making them very versatile in the workplace, and therefore, very appreciated.
So what does your theory say about those of us who are moving from physics to a more serious role in CS?
Disk reliability is highly governed by mechanical failure. Any fruitful attempt to create a more reliable hard drive head design would then logically have to include a reduction of moving parts. Rigid bodies can be secured with far greater precision and tolerance than movable solenoid-driven parts, therefore the goal that is being presented in the granparent's design is one of a 100% stationary head. The only moving part in this system would then be the rotating platters, and the main point of falure would then be the bearing. Fluid bearing and magnetic bearing drives could provide added reliability to those design points, but removing the delicate moving head assembly would have to produce drives with at least an order of magnitude more reliability than current consumer designs.
If the only argument against this is that the magnetic pickup on the head can't be made small enough to place many side by side, I would present the option that the head does not have to cover one linear radius across the platter, but rather each sequential pickup coil could be offset by some angle, thus producing heads spiraling out from the center. This entire head pickup assembly could then be precisely and firmly mounted above the platter and voila!... The most reliable and expensive hard drive ever created.
I dunno about you, but I'd buy one.
And I could imagine a Linux Beowolf cluster of them too...
It's not a different method, it's the same method...
The only difference is if you accidentally route the end you're holding on to THROUGH the center of the cables, those alternating twists tie themselves into a series of half-hitch knots every two twists.
When I was working as a professional sound engineer, I used to have to train stagehands how to coild cables properly. I'd demonstrate, then I'd have them coil theirs and all throw their cables at the same time, side by side.
What I didn't tell them was that I had bets going with the other audio guys as to how many cables would untwist with all those knots in them.
>> That is a very, very nice link, by the way.
Indeed it is. I wrote a few papers in college about musical psychoacoustics and how bizarre the opposing results of the research turn out to be. This guy, however, is the only source that I've read that shows a truly logical, scientific approach to debunk the audiophile mentality.
I hope that there's enough readers on this thread that actually read the entire paper and can understand it.
~Loren
As opposed to just accelerating electrons?
It's actually a pretty disgusting trend in professional audio as well.
b je ctv.htm#1
Manufacturers offer up specifications for their equipment based on the demand for perfectly linear, zero-distortion amplifiers and signal processing equipment. However, all the reviews then go back and say that the sound of a particular distorted source is preferable. At that point, there's really no point in providing a zero-distortion signal chain. Any distortion it produces would be very well masked by the distortion of the source material.
Here is the best source I've read on the subject:
http://www.dself.dsl.pipex.com/ampins/pseudo/su
Please don't slashdot him, I really would like to be able to offer this link to others in the future.
~Loren
The parent poster is absolutely correct in that the goal of producing an amplifier is to create a perfectly linear constant multiplication of an input signal. Any non-linearities must be viewed as flaws in the amplifier design, or at least as limits to its practical range of use. The switch to transistor technology happened so rapidly because they have much better characteristics than tube amplifiers.
All the arguments here can be summed up as such. I feel if we keep these points in mind, we can stop arguing.
1) An amplifier by definition is used only to amplify sound.
2) Distortion is a negative byproduct of a poorly designed amplifier.
3) Tubes significantly distort the sound they amplify by adding a certain color of harmonic content dependent on how much the tube is driven -- this is mainly due to NON-linearities in the circuit.
4) Live and recorded music has developed an enormous dependence on signal processing -- both linear and non-linear. Signal processors can do ANYTHING to the sound, be it EQ, delay, distortion, reverberation, etc.
5) Many sound engineers, audiophiles, guitarists, producers, and listeners have developed a distinct liking to the tone color produced by specific applications of tube amplifiers. Many others can't stand the distortion. Still many others can't stand the distortion and yet purchase $10,000 tube amplifiers. I blame fairies too...
6) The individuals that argue for tube amplifiers are actually arguing for their use as a signal processor that is often conveniently attached to an amplifier.
And here's the real kickers that I've learned through years of live sound and recording engineering:
7) Never tell someone what they like and don't like to hear. They will never change their mind.
8) Never confuse amplification with signal processing, whether it's digital (DSP) or analog (tubes, etc). If a device does both, that's great, but realize that it's doing two jobs for you.
As a side note, most DSP doesn't accurately reproduce tube sounds becuase tube distortion is very nonlinear. DSP works well for linear systems because all linear systems have a 'transfer function' that can be used to simulate that system perfectly. Nonlinear systems do not have a constant transfer function, if they have a transfer function at all, and therefore would require an exponential amount of additional processing in order to recreate nonlinear distortion. Of course, there are tricks...
~Loren
Right... Because then we'd just bomb ourselves and the terrorists would win ;-)
The original poster already responded to this in his link:
2. Use a non solvent-based felt-tip permanent marker to mark the label side of the disc.
Last I checked, alcohol is a pretty damn good solvent... Oh yeah, water is too, actually...
Oil? Not so much, although it may degrade the surface of the media in other ways.
So I would argue that it is not so much "increasing data" but "scientist's increasing faith" that Einstein was right.
Uh oh... He said the "F" word...
I've just spent hours reading all the way to the bottom of these comments. It seems that there are many, many people out there that feel that they are perfectly qualified to analyze the data these satellites will provide. Maybe you are... Maybe you know someone who is... It doesn't really matter.
2 Points:
1) The scientific community is largely based on recognition of accomplishment. You may feel that the taxpayers should get the data, but you'd be acting in haste. You're paying the scientists salaries so that *they* can make important discoveries, not *you*. If you can come up with a genius experiment and design incredibly sophisticated measurement equipment to gather data, then by all means, do it. Then you're called a scientist. However, you're only credible if you can properly analyze that data and present it in a peer-moderated forum. In other words, it's not your experiment. You pay for them to do it, but to suggest that someone else should be able to analyze the data concurrently and take credit for their accomplishments... tsk tsk tsk...
2) Data analysis involves much more than simply plotting theoretical values "against the the data they receive from the gyros". What the non-scientific community doesn't seem to understand is that there is another number associated with data --
-- error.
It's easy to plot out mean values of raw data and compare them to theory. In that case, you're right. There are many, many people out there that would love to determine for themselves if they understand the mathematics of this experiment enough to analyze the data. However, The real experiment is determining to what extent their data can be 'trusted'. In order to do this, they must factor in the sensitivity of *every* piece of equipment used to collect any portion of the data, as well as all of the natural statistical errors that coincide with an experiment of this nature. I would imagine that most of the data collected in experiments of this nature would look like noise to any scientist who did not also have (possibly classified) knowledge of the nature of the instruments being used to collect the data.
Nuclear or quantum physics experiments are notorious for 'conjuring' an amazingly accurate and repeatable value for certain theoretical constants from a set of data points that looks like someone dropped a bag of rice on a piece of graph paper.
Now as far as the drug complaint is concerned, that's an entirely different matter. The scientists aren't looking to make a profit off of their research. Unless by profit you mean future grants and awards that they base their well-being on.
No, you can glamorize musicians all you want. In fact, I'd be willing to bet that most of the top geeks that read Slashdot are fairly accomplished musicians.
Now you can stop glamorizing quite a large number of pop-stars, and I'll be happy.
Well, for one, magnetic fields fall off over distance just like electric fields. Since there is no such thing as a magnetic monopole (at least not that anyone has been able to discover), then magnetic fields have to begin with a dipole field. Additional dipoles put together create quadrapoles and octopoles, etc, which have magnetic fields that fall off all at different rates. This can get complicated...
The point, however, is that the actuator magnets, although very strong, aren't nearly as strong as the read/write heads that are fractions of a millimeter away from the platter.
Now pop down a couple threads to the post about biasing the magnetic field at high frequencies and you just might be confused enough about the topic to actually do a google search on it.
I hope at least...
Hey!!!!
Broadband ISP techs!!!!!
You getting all this?!?!?
Well, if your reasons for wanting an ultimate desktop is simply to put windows to shame, then you'll be waiting a long time.
The reality is that neither windows, nor KDE, nor Gnome, are an ultimate desktop solution. If you want one of them to become the ultimate desktop, then all you have to do is support that desktop and wait. You can't rush innovation.
In any case, the point of my response was that there will *never* be a single ultimate desktop as long as there are individuals willing to put the time in to develop their own desktop tools. I mean, there's not even an ulitmate *windowing* system for linux yet, so don't expect an ultimate desktop. XFree86 is a standard windowing system, but it's by no means the best and only one.
This response annoys me.
This manufacturing technique does not utilize the properties of refraction at all. At no point does the author ever try to get the reader to believe that there is any sort of 'lensing' going because of the water. The problem is diffraction -- specifically, the problem of wavelength-limited diffraction. There is a theoretical limit on how small we can focus a beam of light based on the wavelength of that light. By submerging the process underwater, we *slow* the light down, therefore creating an artificially shorter wavelength. It's as if we increased the frequency of the light without having to manufacture more expensive lasers.
Refraction is the effect we see when that slowing of light at a boundary changes the direction of the incident light. However, in these manufacturing cases, the light is perpendicular to the wafer, therefore no refraction will take place. In fact, if refraction does take place, they will have to compensate for it somehow.
>>All the desktop technologies seem doomed to live side by side forever. sigh.
Exactly how it should be. The whole idea behind the development of free software is that if *you* wanted to develop your own desktop software, then anyone can and will be free to use it. There is already a top-down heirarchy in place for the linux desktop. It's called KDE. It's called Gnome. It's called Enlightenment. Each of these desktops are developed in the same manner as the linux kernel. There's a large number of developers working on different little pieces, and there's a maintainer (or core of maintainers) that coordinates all of their efforts and puts together a finished product.
Just because there's choice doesn't mean you have to choose both, just be glad that you have the opportunity to make a choice in the first place. Sure, all those combined efforts may be put to better use working together on the 'ultimate' desktop, but this is a far more efficient way of determining what that 'ultimate' desktop is.
Let's just think of it as a breadth search of all possible desktop environments, and we can later choose the paths that we like the most and combine those ideas into a single desktop environment in the future.
Breakthroughs rarely happen from focused efforts... Breakthroughs happen because an individual has a vision of a far more efficient method and acts upon that to create a new way of doing things.
A windows-like desktop is not even close to a breakthrough, but getting more support for the linux desktop in general will spur more development in the area and may help some individual to come up with a completely new, 'breakthrough' desktop for you.
I'll ride my B.S. in physics in on the coat-tails of the PhD.
It is true that the energy levels we are dealing with are miniscule. However, if they can be heard by your ear, they can be heard by others. There are several ways that sound waves lose intensity -- not energy. The most obvious is dispersion. Sound follows the distance-squared law just like any point-source radiation (we'll ignore that a speaker has area, and is therefore not a point-source. If you really wanna see scary math, I'll show you some area or volume-source sound fields). So if you want the sound to be less intense, easy... Just get further away from it.
The next method of sound reduction is absorption. This is when the sound energy causes something to vibrate, transferring energy into heat. Normally, as in those foam coverings we see on studio walls (or around your headphone earpiece), the sound energy is trapped inside the small pockets of air that make up the foam or fiberglass sound insulation, and simply bounce around inside until the energy eventually gets dispersed into the solid material of the foam itself.
The next method of sound reduction is reflection. Of course, this does nothing to actually get rid of the energy, but rather channels it away in another direction. Remember though, there is no such thing as a perfect reflector. Every reflector will absorb a tiny bit of energy from the source wave.
So the reason you don't hear the output of the headphones if you're not wearing them is because almost all of the sound energy is trapped between the ear and the speaker and simply bounces around in there until it is all either absorbed by the headphone casing or your own flesh. Of course, if you got right up next to the headphones, I'm certain you could hear plenty of sound being generated by the vibration of the headphone casing itself.
What we should all realize about this particular application is that the sound source is almost purely periodic. The only part of the fan noise that can't be predicted is the chaotic sound created by the turbulence of the air at the tips of the fan blades. This means that through some 'simple' correlation techniques, the fan noise can be sampled and an exact cancellation source can be calculated -- for a given listening location. This is unlike the headphones application, which has to deal with computing a large variety of random audible noises. You'll probably notice that the ability of these devices to cancel sound is limited to a certain bandwidth of the middle range of human hearing, and even then only by about 10-15 dB at best. It will work fairly well on the lower frequencies, but will rely almost completely on the mass of the headphone casing itself to block the higher frequencies from reaching your ear.
The most interesting part of this problem from a physicists point of view will be how to get around the doppler effects of sampling and reproducing a waveform in a moving airstream. Also, fans don't produce a steady stream of air -- rather, they produce a pulsing stream of air that varies depending on your location in front of the fan. Any musician that's tried to practice in a room with a ceiling fan will understand that frustration. I suppose that whatever software you use to calculate a cancelling waveform can be used to perform those calculations as well.
here
Pick a wavelength, find roughly the index of refraction, and you can roughly determine the speed of light in the doped silicon.
I think most people who post questions like this are still missing the point. Distance limitations are determined largely by inefficiencies in power transfer, which are almost irrelevent when dealing with light transmission down a fiber. Basically, once you have the light in a waveguide tuned to that frequency, it doesn't escape except by quirks of quantum mechanics.
So to answer that, it's a question of energy and heat, not about speed.
~Loren
Photonics has been the 'next big thing' for quite a while now. I even decided to get a degree in photonic engineering. What do I do now? I teach music and run sound at rock concerts...
Photonic engineering (or electro-optics, as us physicists like to call the research side of it), is plagued by the same problems as the rest of the tech industry. Few companies are willing to fund the research in developing manufacturing techniques, therefore the incredible research that has been done in the field will sit in the journals getting dusty (as it has been for the past 10 years).
I will say that this is a big step for the industry though. Not because of Intel's 'breakthrough discovery', but simply because with a big name company making a press release about new photonic computing technology, many other companies will be tempted to scramble into that field as well. Someday down the line, I may actually be able to work in this field simply because of this press release...
*toast* Here's to hoping, right!
~Loren
Sorry, accidentally posted anonymously the first time:
The limitation on physical distance in an electrical medium is dictated by its impedance, which dissipates the electrical energy in the form of heat. This creates an enormous problem of power loss, which increases linearly with the distance of the transmission line.
An optical waveguide, such as fiber or the silicon waveguides mentioned in the article, see no such losses due to electrical impedance.
Theoretically, as long as the parameters are met for photonic propagation, light will stay in the waveguide indefinitely. However, there are still losses due to imperfections and impurities in the medium itself, caused by microscopic deformities, bubbles, splices in the fiber, etc. There are also some losses dues to quantum effects, which we see in the form of 'evanescent' waves that tunnel outside of the boundaries of the waveguide.
What you really want to be asking is what is the transmissive and absorbtive properties for the silicon medium they use for the particular wavelength(s) of light that they are developing the technology with. If you know that, then combined with the effects above you can get a decent estimate of the power dissipation of the system for a given photon source.
My feeling, without performing the calculations, is that you will be pleasantly surprised at how little energy will be dissipated in the form of heat.
~Loren
Another point that I haven't seen moderated up to my reading level --
Optical processing works theoretically similar to electronic processing. The main differences are that instead of transferring signal via an electrical field down a conductor, you transfer signal via photons travelling down a waveguide. The advantage that I haen't seen discussed yet is that photons travelling down a waveguide exhibit no resistive losses in the form of heat. In fact, optical processing requires very little current, and thus produces very little heat.
The heat issue is something I think all the readers of this site can appreciate.
In the end, it will all come down to manufacturing costs. If this technology can be manufactured in such a way that it is more cost efficient than semiconductor electronics, then it WILL be the future.
My personal belief is that optical electronics are the only future we can expect. We cannot send any signal faster than the speed of light. With optical circuitry, as stated in a previous post, we are ONLY limited by the speed at which we can gate a source of photons.
Who knows? The technology may progress very soon to the point at which quantum computing -- counting individual photons of light -- may become our ultimate limit of processing speed. How would that change the state of computing? Knowing that there is no possible way to process and transfer data any faster without redefining the laws of relativity???
~Loren
Our ears are much less 'fooled' than our eyes are. Many of the posts suggest that what is coming out of our sound cards is anything less than a 44.1kHz, stereo, 16 bit audio stream. If you think that somehow your speakers vibrate any differently because the source was encoded as an MP3 you are frightfully mistaken.
The whole point of audio compression is to recreate the original waveform as accurately as possible. I challenge any one of you to a blind A/B test of uncompressed 16 bit CD audio vs. 320 kbit MP3. Encoding with lower bitrates results in a clearly audible distortion. Nothing fooling our ears there. We listen to dstortion all the time. Chances are, unless you have a very nice stereo system, very litle of the original waveform reaches your ear undistorted.
The true irony of this situation is that 90% of the music that people listen to is distorted on purpose. Electric guitars, synthesizers, and basically any compression and EQ processing add unnatural distortion to musical instruments. In fact, noise and distortion are natural artifacts of any musical instrument. If they weren't there, every instrument would end up sounding like it was straight out of a cheap Casio.
This is definitely not a scientific article. There is no experiment, there is no data, there is no experiment, there is no statistical analysis, and there is no explanation of error.
However, if the theory is that there are certain kinds of distortion that can damage hearing at greater than its natural failure rate, THEN we may have something worthy of scientific study.
~Loren
Musicians listen to the music.
Engineers listen to the sound.
Audiophiles listen to the noise.
All my music professors (except for the sound design guys) had some pretty crappy stereos at home. They simply had no reason to upgrade because what they have reproduces what they care to hear just fine. Musicians study for years in order to learn how to analyze sound in a completely different manner than the average listener. They're not out to recreate sound, they're trying to recreate the beauty of the musical composition itself.
~Loren
Well, if you're going the speed of light, you ARE, in fact, light. However, if you're going very, very close to the speed of light, the light coming from your headlights will be constrained to a tight cone projecting in the direction of travel. Sort of a relativistic tunnel vision.