Actually, Newtonian mechanics is "wrong", but not by a long shot. Special Relativity is more correct (we'll ignore GR for now), but the corrections are on the order of (v/c)^4 (using expressions for kinetic energy as a benchmark).
Academia held on to Newton's theory because
1)It is close enough for the vast majority of earth bound applications without the added complexity to get that 14th decimal corrected.
2)It is a simple and intuitive theory that provides a good jumping off point for non-intuitive theories like quantum mechanics and relativity.
I been teaching (about 18 years) freshman/sophomore level physics, primarily engineering students. I try to encourage study groups outside of class and my most successful years as a teacher are when the students are successful in forming these groups.
I also subscribe to the "see it, do it , teach it " philosophy of learning where you develop the deepest understanding of materials when you are forced to explain it to someone else. I use this argument on my better students and the result generally is better performance all around.
50 years? BLEH!
With the acceleration of culture and technology, shouldn't the modern duration of copyright (and other intellectual property rights) be shorter than the original 17 years, rather than longer? The video makes the excellent point that all new works borrow from existing materials (culture), and so should revert to the culture (public domain) after the owners and/or creators have had reasonable opportunity to profit from their works.
I have to respectfully disagree. Blender's learning curve is horrendous. I spent a fair amount of time (all of my free time+ over the course of about 3 weeks) and got no where when trying to create simple animations for my physics students. I spent a weekend with POV-Ray and completed the first of many such short animations.
I know that Blender's capabilities blows POV-Ray's out of the water, but I couldn't do simply and easy stuff easily with Blender that I can with POV-Ray. Every so often I'll spend a weekend with Blender and make some incremental progress in my understanding of how it works for still scenes, but I haven't even gotten near the animation tools.
Perhaps Blender is easy to pick up for those who are already familiar with similar professional level tools, but that does not describe the entire (or even the important part) of the learning curve for the rest of us.
causality and locality are already dead aint they? Really? I missed the obituray. Got a journal citation? (something other than Cramer's interpretational abuse of "retarded wave functions" I hope.)
anyway.. I'm quite happy to say we don't know enough to say one way or another whether or not the speed of light is a real barrier to an advanced civilization. Are you saying that there is significant doubt about relativity? Relativity is solid; "star trek" type interstellar voyages are beyond unlikely. You seem implying a doubt in relativity that does not exist within the physics community. There is I suppose in some technical sense we don't know for sure, but this is not like a late 1800's claim that man will never fly, this is an inherent limitation imposed by nature.
Exotic matter is believed to exist. Techniques for using energy to make the gravitational effects of exotic matter are believed to be possible. So wormholes and warp drives are not out of the question, theoretically.. but it's still an insanely difficult engineering proposition, even if we knew how to do it today we couldn't do it. Wormholes may or may not exist within the context of general relativity, however the causality issue is still a VERY strong argument against. There is no observational evidence to support the existence wormholes, and the impression I have from my GR courses and a talk by Kip Thorne (admittedly some 20 years ago) is that they would be inherently unstable if they should manage to pop briefly into existence. Thorne's talk was basically about how, in principle, an arbitrarily advanced civilization might be able to hold a wormhole open.
Warp drives possible even in principle? Thats news to me, especially since even with (naturally or "artificially") curved space time, the geometry is locally Lorentz. This basically means that all the issues with flat space time (special relativity) for superluminal adventures still hold true with curved geometries.
Dark matter or energy wouldn't be expected to provide any magical means of providing infinite energy for FTL. They just differ in the details with which they provide curvature for space time.
Believe me, I'd love to think that we'll someday have an easy way of getting off this rock, we live in the universe we live in. The evidence is that the only way out there is the long slow route with no shortcuts.
no no no I was trying to point out that inertia and the light speed "barrier" are not one in the same. Inertia clues us in how things with mass cannot be made to go to the speed of light (it would take infinite energy/work). However, the very structure of space time prohibits FTL motion or even communication (unless you are willing to sacrifice causality: cause always precedes effect). As soon as you have FTL motion/communication, you have the equivalence of time travel (backwards in time)/ability to send messages into the past. And believe me, physicists are VERY reluctant to give up causality.
Actually, things without inertia (photons, for example) automatically go the speed of light. As a particle's energy increases (beyond rest mass energy), it becomes more "photon like" in that it asymptotically approaches the speed of light. So removing inertia will eliminate that inconvenient acceleration, but leave in place the ultimate speed limit.
It's not that the Helium in and of itself is dangerous (it is an inert gas, after all) but rather that it isn't oxygen. Inhaling the helium from a helium balloon will make you light headed (lack of oxygen) but the real danger is if you keep breathing helium w/out oxygen, you don't realize you're suffocating because the carbon dioxide is still being cleared from you lungs and its the CO2 that triggers the sensation of suffocation.
Indeed, it is quite a stretch to say that putting a paper up on arXiv.org is "published" in any normal sense (say onethat would be accepted by a tenure review committee). However we do have
Is Violation of Newton's Second Law Possible?
A. Yu. Ignatiev
Phys. Rev. Lett. 98, 101101 (2007)
as well as
Mirror dark matter and large scale structure
A. Yu. Ignatiev and R. R. Volkas
Phys. Rev. D 68, 023518 (2003)
Geophysical constraints on mirror matter within the Earth
A. Yu. Ignatiev and R. R. Volkas
Phys. Rev. D 62, 023508 (2000)
and others.
The author has a real publication record. For phys rev and especially phys rev lett, the crank filters are a little more effective. As with the parent, this is not my field. However, my initial knee jerk reaction (crank!) has abated somewhat.
hrmmm, I'm newish to slashdot (as you can see by my ID) and thought there was a user to user message system that didn't need email. Oh well, hopefully I've changed my display email options.
Excellent observation. The provision as it was written would have barred companies from encouraging or providing mechanisms for their customers to contact legislators regarding issues of import - unless, of course, said company "registered" with the government and reported all activities and expenditures. And that is a massive free speech problem. Nobody wants to construct a reporting mechanism, legislators know that. It's much easier to simply stop trying to engage in advocacy.
Sorry, I am not convinced that free speech rights were to apply or should now apply to companies. Citizens, absolutely, but companies, no. So monitoring corporate efforts to persuade comes under truth-in-advertising and is not a "massive free speech problem". Harassing an 86 year old man with the secret service for a letter to the editor is a massive free speech problem. http://abcnews.go.com/US/wireStory?id=2811492
Transactional's forward and backward travelling waves? Bleh! There were a lot of things (such as mixed state analysis) that I could never figure out how to do in that framework.
Copenhagen always seemed to me to be more of a prolonged state of denial than an actual interpretation. For me, Everett's the man!
This is an excellent point, but it cuts both ways. As you've pointed out, the available evidence during the Middle Ages made an Earth-centered universe viable. Thus, it was entirely possible to rigorously follow the scientific method and still conclude we are at the center.
Ehhhhh, probably the biggest ramification is that it is the earth that moves. So how much does it move? The history of how we understand earth is a beautiful display of how science works and advances.
You can go pretty far modeling everyday physical phenomena by using a flat, stationary earth. Expanding your horizons to satellites, you extend your model to round stationary earth plus Newton's Gravity. Interplanetary probes, you need more. At what point do you need to account for General Relativistic effects? Obviously not if your calculating the range of your potato gun.
Rigorously scientific, and quite wrong. This is something that's overlooked all too often -- Science can never promise Truth. The best any theory can hope for is to be very well verified. Please don't get me wrong -- the Scientific Method works better than any other method known to us. We can never know with absolute certainty that our conclusions are true, but using any other method is much worse. I'm not advocating that we replace Science with something else; I'm just pointing out that the conclusions are never absolute.
But but but but they weren't "quite wrong"! They were merely improved upon. Better models came along as the limitations of the old models were recognized. (OK, it took a while) However, let me point out that the existence of new models and theories which have a geater range of validity than old models does not negate the utility of those old models. Most engineers learn classical mechanics and spend little if any time with relativity and quantum even though classical has been superceded.
So no, there is no cutting both ways. The hope and expectation for improvements in climate science is no reason to complacently wave away the predictions of today. However, we have recent history (tobacco industry)of junk science obscuring and obstructing. And that is the something many of us keep in mind in the current global warming debate.
It still doesn't fit in with the observed motions of the other planets. Why would Mercury never stray far from the Sun if it's going around the Earth? Why does Venus get larger and smaller as it moves around?
A good theory fits all data, not just a little bit of cherry picked data.
Ptolemy's model did acount for inferior as well as superior planets, including retrograde motion and maximum elongation. It did about as well Copernicus's model (they were both equally mundane) and thus the lack of observable stellar parallax lead back to stationary earth. It's not really until Kepler that a better model arrives, and then Newton to explain Kepler's phenomenology.
I've never heard of naked eye reliable observation that Venus changes size, so thanks for the tip (I teach a conceptual astro course, this would be an interesting tidbit).
I'll have to differ with your description of a good theory (unless science is to be nothing more than grand curve fitting). A good theory should fit some data, provide a conceptual framework and be able to provide predictions. I don't think we're really anywhere near a Theory Of Everything yet.
Exactly correct. Everyone knows that the present of a specific scientific principle is decided by a central committee and then approved by the electorate at large. It's an excellent system, look how the Catholic church managed to keep us at the centre of universe!
Speaking of strawmen, never mind that the lack of observable stellar parallax made stationary earth models scientifically more tenable. See the discussion of Tycho's observations here:
http://csep10.phys.utk.edu/astr161/lect/history/br ahe.html
I used to read Chrichton's fiction, but the difference between Jurassic Park the movie (a dark tale of the consequences of conscience-less and careless commercial exploitation of science) and Jurassic Park the movie (a simple horror flick, where "science" seems to be the bad guy, because no character seemed to bear any responsibility). It was clear to me that Chrichton had become a prostitute, a process that seems to have accelerated lately particularly with his own confusion about the fictional nature of his work. The relative lack of fatalities of major characters in the movie compared to the book really took the edge off of what I thought was the major theme.
>>Better to have everyone pay into an education system at their level of ability, and have everyone take out of it based on their need and inherent abilities.
>Wow, your last sentance sounded uncomfortable close to Orwell.
Orwell? Marx maybe, I don't think that's Orwell
>> Only very rarely is someone widely ridiculed who is actually correct.
>
>You're wrong. Read something about the lives of geniuses in the field of science and inventions.
Well no, he is not wrong. You seem to be confusing a couple of issues.
First off, it simply can not be true that a significant fraction of people who have been ridiculed are actually correct because they have wildly divergent claims.
Secondly, you seem to be conflating what I would call the hollywood version (or sometimes simple urban mythology) with actual history. I tried to make this point regarding Einstein, who was not ridiculed for his theories by the scientific establishment, elsewhere in this thread.
These "vindicated genius" stories are often touted by the crazies as if it might be evidence that their unpopular (and often untenable) positions are valid. The cries of "well, they persecuted Galileo and he was right" ignore their their faulty logic as well as history.
Anyone who thinks Galileo was a complete innocent should determine the role of Simplico in Galileo's Dialogues. Not that I'm saying the church was right, but I would way it is along the lines of someone working in the current US administration complaining about fascist tendencies and expecting to get promoted.
So, having read something accurate about the lives of geniuses in the field of science and inventions, I can't say there any support to the notion that revolutionary ideas are widely first ridiculed and then eventually accepted.
Initially, when Einsteing presented his ideas, they all thought he was a member of such "club of crazies" too.
Actually, no. The physics community accepted the break throughs produced by Einsteing[sic] as they were published, to the extent they were experimentally accessible. (Special and especially General Relativity were really pushing the envelope, but were not viewed as "crazy".)
Or perhaps you meant thought by the general public to be crazy, which seems to think the same of first semester mechanics (a la Newton).
Slashdot Mirror
Actually, Newtonian mechanics is "wrong", but not by a long shot. Special Relativity is more correct (we'll ignore GR for now), but the corrections are on the order of (v/c)^4 (using expressions for kinetic energy as a benchmark).
Academia held on to Newton's theory because
1)It is close enough for the vast majority of earth bound applications without the added complexity to get that 14th decimal corrected.
2)It is a simple and intuitive theory that provides a good jumping off point for non-intuitive theories like quantum mechanics and relativity.
AMEN!
I been teaching (about 18 years) freshman/sophomore level physics, primarily engineering students. I try to encourage study groups outside of class and my most successful years as a teacher are when the students are successful in forming these groups.
I also subscribe to the "see it, do it , teach it " philosophy of learning where you develop the deepest understanding of materials when you are forced to explain it to someone else. I use this argument on my better students and the result generally is better performance all around.
"I am old enough to remember when everybody railed about global cooling (about 30 years ago)."
And I am old enough to call bull on your pseudo memories.
Is this really the sum total of what "skeptics" bring to the table? Or was this entire post some truly subtle satire which I entirely missed?
The steady rollback of the Enlightenment *is* news for nerds.
Somebody modded this down? Aren't you paying attention? Or has intellectualism really breathed its last gasp?
50 years? BLEH!
With the acceleration of culture and technology, shouldn't the modern duration of copyright (and other intellectual property rights) be shorter than the original 17 years, rather than longer? The video makes the excellent point that all new works borrow from existing materials (culture), and so should revert to the culture (public domain) after the owners and/or creators have had reasonable opportunity to profit from their works.
I have to respectfully disagree. Blender's learning curve is horrendous. I spent a fair amount of time (all of my free time+ over the course of about 3 weeks) and got no where when trying to create simple animations for my physics students. I spent a weekend with POV-Ray and completed the first of many such short animations.
I know that Blender's capabilities blows POV-Ray's out of the water, but I couldn't do simply and easy stuff easily with Blender that I can with POV-Ray. Every so often I'll spend a weekend with Blender and make some incremental progress in my understanding of how it works for still scenes, but I haven't even gotten near the animation tools.
Perhaps Blender is easy to pick up for those who are already familiar with similar professional level tools, but that does not describe the entire (or even the important part) of the learning curve for the rest of us.
Warp drives possible even in principle? Thats news to me, especially since even with (naturally or "artificially") curved space time, the geometry is locally Lorentz. This basically means that all the issues with flat space time (special relativity) for superluminal adventures still hold true with curved geometries.
Dark matter or energy wouldn't be expected to provide any magical means of providing infinite energy for FTL. They just differ in the details with which they provide curvature for space time.
Believe me, I'd love to think that we'll someday have an easy way of getting off this rock, we live in the universe we live in. The evidence is that the only way out there is the long slow route with no shortcuts.
no no no I was trying to point out that inertia and the light speed "barrier" are not one in the same. Inertia clues us in how things with mass cannot be made to go to the speed of light (it would take infinite energy/work). However, the very structure of space time prohibits FTL motion or even communication (unless you are willing to sacrifice causality: cause always precedes effect). As soon as you have FTL motion/communication, you have the equivalence of time travel (backwards in time)/ability to send messages into the past. And believe me, physicists are VERY reluctant to give up causality.
Actually, things without inertia (photons, for example) automatically go the speed of light. As a particle's energy increases (beyond rest mass energy), it becomes more "photon like" in that it asymptotically approaches the speed of light. So removing inertia will eliminate that inconvenient acceleration, but leave in place the ultimate speed limit.
It's not that the Helium in and of itself is dangerous (it is an inert gas, after all) but rather that it isn't oxygen. Inhaling the helium from a helium balloon will make you light headed (lack of oxygen) but the real danger is if you keep breathing helium w/out oxygen, you don't realize you're suffocating because the carbon dioxide is still being cleared from you lungs and its the CO2 that triggers the sensation of suffocation.
Is Violation of Newton's Second Law Possible? A. Yu. Ignatiev Phys. Rev. Lett. 98, 101101 (2007)
as well as
Mirror dark matter and large scale structure A. Yu. Ignatiev and R. R. Volkas Phys. Rev. D 68, 023518 (2003)
Geophysical constraints on mirror matter within the Earth A. Yu. Ignatiev and R. R. Volkas Phys. Rev. D 62, 023508 (2000)
and others.
The author has a real publication record. For phys rev and especially phys rev lett, the crank filters are a little more effective. As with the parent, this is not my field. However, my initial knee jerk reaction (crank!) has abated somewhat.hrmmm, I'm newish to slashdot (as you can see by my ID) and thought there was a user to user message system that didn't need email. Oh well, hopefully I've changed my display email options.
Ya, I've danced around the gmail pages, and I don't have the text messaging capability required. Can anyone send me a Gmail invite?
>> The quality of the "news stories" that slashdot carries has gone downhill drastically in recent months.
>And the number of comments stating that the quality of the news stories is declining has stayed about constant for several years.
That is, the rate of change of decline has been constant, therefore there the decline has not been accelerating. This is good news, right?
Hrmm, "Applications of Calculus to (Perceived) Slashdot Quality". Maybe I can get a paper out of this...
Transactional's forward and backward travelling waves? Bleh! There were a lot of things (such as mixed state analysis) that I could never figure out how to do in that framework.
Copenhagen always seemed to me to be more of a prolonged state of denial than an actual interpretation. For me, Everett's the man!
Ehhhhh, probably the biggest ramification is that it is the earth that moves. So how much does it move? The history of how we understand earth is a beautiful display of how science works and advances.
You can go pretty far modeling everyday physical phenomena by using a flat, stationary earth. Expanding your horizons to satellites, you extend your model to round stationary earth plus Newton's Gravity. Interplanetary probes, you need more. At what point do you need to account for General Relativistic effects? Obviously not if your calculating the range of your potato gun.
Rigorously scientific, and quite wrong. This is something that's overlooked all too often -- Science can never promise Truth. The best any theory can hope for is to be very well verified. Please don't get me wrong -- the Scientific Method works better than any other method known to us. We can never know with absolute certainty that our conclusions are true, but using any other method is much worse. I'm not advocating that we replace Science with something else; I'm just pointing out that the conclusions are never absolute.But but but but they weren't "quite wrong"! They were merely improved upon. Better models came along as the limitations of the old models were recognized. (OK, it took a while) However, let me point out that the existence of new models and theories which have a geater range of validity than old models does not negate the utility of those old models. Most engineers learn classical mechanics and spend little if any time with relativity and quantum even though classical has been superceded.
So no, there is no cutting both ways. The hope and expectation for improvements in climate science is no reason to complacently wave away the predictions of today. However, we have recent history (tobacco industry)of junk science obscuring and obstructing. And that is the something many of us keep in mind in the current global warming debate.
A good theory fits all data, not just a little bit of cherry picked data.
Ptolemy's model did acount for inferior as well as superior planets, including retrograde motion and maximum elongation. It did about as well Copernicus's model (they were both equally mundane) and thus the lack of observable stellar parallax lead back to stationary earth. It's not really until Kepler that a better model arrives, and then Newton to explain Kepler's phenomenology.
I've never heard of naked eye reliable observation that Venus changes size, so thanks for the tip (I teach a conceptual astro course, this would be an interesting tidbit).
I'll have to differ with your description of a good theory (unless science is to be nothing more than grand curve fitting). A good theory should fit some data, provide a conceptual framework and be able to provide predictions. I don't think we're really anywhere near a Theory Of Everything yet.
Speaking of strawmen, never mind that the lack of observable stellar parallax made stationary earth models scientifically more tenable. See the discussion of Tycho's observations here: http://csep10.phys.utk.edu/astr161/lect/history/b
I used to read Chrichton's fiction, but the difference between Jurassic Park the movie (a dark tale of the consequences of conscience-less and careless commercial exploitation of science) and Jurassic Park the movie (a simple horror flick, where "science" seems to be the bad guy, because no character seemed to bear any responsibility). It was clear to me that Chrichton had become a prostitute, a process that seems to have accelerated lately particularly with his own confusion about the fictional nature of his work. The relative lack of fatalities of major characters in the movie compared to the book really took the edge off of what I thought was the major theme.
h ton-thriller-state-of-fear.html
Anyone who takes State of Fear too seriously should perhaps consider what actual scientists (as opposed to those who dabble in sciencey-stuff) have to say about that work: http://www.ucsusa.org/global_warming/science/cric
>>Better to have everyone pay into an education system at their level of ability, and have everyone take out of it based on their need and inherent abilities.
>Wow, your last sentance sounded uncomfortable close to Orwell.
Orwell? Marx maybe, I don't think that's Orwell
>> Only very rarely is someone widely ridiculed who is actually correct.
>
>You're wrong. Read something about the lives of geniuses in the field of science and inventions.
Well no, he is not wrong. You seem to be confusing a couple of issues.
First off, it simply can not be true that a significant fraction of people who have been ridiculed are actually correct because they have wildly divergent claims.
Secondly, you seem to be conflating what I would call the hollywood version (or sometimes simple urban mythology) with actual history. I tried to make this point regarding Einstein, who was not ridiculed for his theories by the scientific establishment, elsewhere in this thread.
These "vindicated genius" stories are often touted by the crazies as if it might be evidence that their unpopular (and often untenable) positions are valid. The cries of "well, they persecuted Galileo and he was right" ignore their their faulty logic as well as history. Anyone who thinks Galileo was a complete innocent should determine the role of Simplico in Galileo's Dialogues. Not that I'm saying the church was right, but I would way it is along the lines of someone working in the current US administration complaining about fascist tendencies and expecting to get promoted.
So, having read something accurate about the lives of geniuses in the field of science and inventions, I can't say there any support to the notion that revolutionary ideas are widely first ridiculed and then eventually accepted.
Initially, when Einsteing presented his ideas, they all thought he was a member of such "club of crazies" too.
Actually, no. The physics community accepted the break throughs produced by Einsteing[sic] as they were published, to the extent they were experimentally accessible. (Special and especially General Relativity were really pushing the envelope, but were not viewed as "crazy".)
Or perhaps you meant thought by the general public to be crazy, which seems to think the same of first semester mechanics (a la Newton).