Posted: Wed Dec 08, 2010 4:35 pm Post subject: Bohr, Heisenberg and Schroedinger
As on Mycsw:
The Art of Prediction - HIST 403 - 1 (B)
Assigned: Saturday, December 4 | Due: Thursday, December 9
What is different about the discipline of science because of the contribution of each of these scientists?
Project: Outline your answer to the question, give 4 pieces of evidence for your answer and determine the format you will use.
The work of these scientists profoundly changed the discipline of science. Bohr completely changed the model of the atom and quantized the things that take place on an atomic scale. He challenged what was considered ‘true’ in old physics, and showed that they were imprecise. Bohr’s work completely reformed physics and he ”was happy to force this confrontation between the old physics and the new” (p127). So he changed the discipline of science by not only redefining physics but by completely redefining known concepts at the foundation.
Bohr also changed the way people looked at science and physics by “reminding himself and his colleagues that physics is not a grand philosophical system…Physics concerns what we can say about nature” (p129). He changed the way people viewed science by separating philosophy from strict observation and experimentation, and defining science through nature.
Bohr along with Heisenberg also changed science as a discipline by saying that light can be both a particle and a wave. They showed that particles and waves are abstractions that can work complementarily. They thought outside the box in this new way. By showing the these concepts we use to grasp science can in fact be abstractions that work together set precedent for scientists can do this in the future. Now scientists can see terms like these that seem to be set in stone, and challenge them to see how they work together.
My question is, are these things directly related to the quest for light? I think that they are, but I can’t figure out how to articulate it.
Bohr --- Besides challenging the fundamental (a priori like) foundation of phsyics in his time, Bohr points out the major flaw of: "Quantum conditions ruled on the atomic scale [with] instruments for measuring those conditions worked in classical ways," (137.) Essentially, new, radical ideas paired with traditional methodology will ultimate limit what could potentially be known. By accepting the results of experiments in their given terms (proof for waves in the context of one experiment, evidence of particles in another,) Bohr's solution is that one must "Accept the different and mutually exclusive relationships as equally valid and stand them side by side to build a composite picture...Light as particle and light are mutually exclusive abstractions that complement each other," (137) This viewpoint in science is HUGE----Bohr effectively sacrifices the comfort an all encompassing, categorical classification of light in a favor of a more complicated, contradictory, yet still more comprehensive understanding of its form. This concession, (almost,) radically alters the discipline of Science because the idea of letting to paradoxical concepts coexist was unprecedented. Furthermore, Bohr's acknowledgment of instrumental limitation inasmuch that traditional instruments can't answer/prove non-traditional questions and theories is brand new as well.
Schrodinger---"Claimed that it [his mathematical derivations] represented the reality of the interior of the atom, that not particles but standing matter waves resided there, that the atom was theereby recovered for the classical physics of continuous process and absolute determinism...Schrodinger offered, instead, multiple waves of matter that produced light...the waves adding their peaks of amplitude together." (134) What I got from that was essentially that Schrodinger circumvented the paradoxes and unanswered questions that Bohr's jumping electrons and particles presented. In this sense its hard to see Schrodinger as one who's take on atoms and light (?) really changed the discipline.
Despite Bohr claiming that Schrodinger had "brought atomic physics a decisive step forward," (135) This debatable progression for atomic physics doesn't seem indicative of a fundamental shift in methodology nor thinking. Heisenberg on the other hand, I think absolutely altered Science due in-part to his own response to Schrodinger's holey work. Heisenberg's Uncertainty Principle (136) ultimately disproves the pre-existing conception of "strict determinism," (136) in physics. Essentially, one could never--neither theoretically nor literally---account for the time and space of any given particle because nature is such that if one measurement can be established another must be inherently blurred. This idea of Hesienberg provides Science with a monumental shift because his principle identifies the "granularity of the universe," (136) wherein estimates of particles' locations in space and time can only ever be predicted on a statistical level. This completely dismisses the neat package Schrodinger attempts to present (harkening to classical physics) in his wave of matter theory.
CONCLUSION: BOHR AND HEISENBERG'S CONCLUSIONS TO THE QUESTION "WHAT IS LIGHT" CHANGED THE DISCIPLINE OF SCIENCE, SCHRODINGER'S DID NOT.
Bohr
-Embracing Paradoxes (Light as a particle and a wave)
-Contradictions that are mutually exclusive-not simultaneous, but both existing separately.
-Discontinuous States of Being ( Jumping Electrons) Defies the Continuous Flow of Classic Mechanics
-Bohr absolutely refuses to accept arguments/principles that are not grounded in cold, hard facts.
-Recognizes the Authoritarian Characteristics of Philosophy
-Avoids Coloring His Own Scientific Experiments with the fanciful notions of Philosophy.
-Reform Movement in Physics-Old vs. New.
-We Cannot Know Everything (Like where electrons are in between various atomic states/orbits.) In addition, we can't know everything because we can't perceive of everything. (Limits of the Empirical.)
-Sees the difficulty of language, because terms often obscure meaning.
Heisenberg
Uncertainty Principle:
-Effects of Multiple Measurements (Velocity, Position) on One Another. This idea squares with Kant's idea of the knower influencing what is known.
-Predictions Can Only Be Statistical, because quantum matter behaves somewhat randomly, but according to probability.
-Nullifies Determinism Within Classical Physics
-Limits on the clarity of truth/certain knowledge about nature that scientists can achieve.
-Importance of Mathematics
Schroedinger
-Importance of Mistakes To Acheiving Progress
-Simplified Math Needed For Quantum Mechanics
Like Rachel, I agree that Schroedinger was clearly the least important of the three scientists. Something that surprised me was Einstein's assertion that "God does not throw dice." I didn't expect the most famous scientist in modern history (depending on your version of modern) to be preoccupied with a higher power at all. But, like particles and waves, who's to say that religion and science cannot coexist? (Clearly they're not mutually exclusive if Einstein's God is affecting his science but, in theory, religion and science could still exist side by side without necessarily limiting one another...or must they limit one another, according to Bohr's idea of mutual limitations?
Bohr: Bohr’s work centered around what classical scientists would have shuddered at. As a scientist, he often came to assumptions, but these assumptions progressed physics and science, for classical scientists had often hit walls in trying to explain the details and prove the most complex mind bending theories to uphold old laws. “Bohr insisted as one of the two ‘principal assumptions’ of his paper that the electron’s whereabouts between orbits cannot be calculated or even visualized… By contrast, the continuous process predicted by classical mechanics… tears the atom apart or spirals it into radiative collapse.” (128) By simply accepting this, physics and the scientific community could move on, but classical mechanics, or Rutherford’s atom model (which tried to adhere to Newtonian Physics), held progress back.
This idea of acceptance in science turns up again with Einstein’s refusal to accept the universe’s structure as “unknowable” and that “statistics rule” (139). Basically, Einstein refused the uncertainty principle which had shattered the standard of determinism in classical physics. But despite the abundance of proof and support for the theory, Einstein held fast to his beliefs, like many scientists before him. So Bohr and Heisenberg’s ability to come to such vague conclusions in science and throw out the determinist conventions of old physics meant groundbreaking change and progress in quantum mechanics and the way we think about the universe, for the modern student may be baffled by light’s tendency to act as both a particle and wave, but does not fundamentally reject its uncertainty.
Bohr’s solution to science was “to accept the different and mutually exclusive results as equally valid and stand them side by side to build up a composite picture of the atomic domain… He called for renunciation of the godlike determinism of classical physics… Light as a particle and light as wave, matter as particle and matter as wave, were mutually exclusive abstractions that complemented each other… they could not be merged or resolved; they had to stand side by side… but accepting that uncomfortably non-Aristotelian condition meant physics could know more than it otherwise knew.” (138)
Again, I don't like the idea of saying how the entire discipline of science changed because of three physicists, as it still uses much the same processes and methods as it did before them. That said, I will admit that some pretty concrete changes were made to the discipline of physics and, to a degree, science as a whole.
Bohr in particular made a few crucial decisions and statements that I think colors a lot of modern science. Importantly, he makes the attempt to not allow authoritarian views held in philosophy and classical physics to interfere with his work (P. 127-28 P. 132). He also recognized that science has its share of limitations (P. 129). Science is a human construction and is limited by human perception.
Schroedinger, in my opinion, did for the mathematics of quantum mechanics what Newton did for the scientific method; refined it. Shroedinger simplified the equations needed for quantum theory (P. 134) and simply made it more accessible.
Bohr
- Light can be both a particle and a wave.
- Put old physics together with new physic.
- "He points out that the idealized concepts we use in science must ultimately derive from common experiences of daily life which cannot themselves be further analyzed." pg 129
Heisenberg
- Uncertainty Principle!
* This is so revolutionary to the discipline of science. Heisenberg admitted that we can't be certain about everything, there will be some unknown. "there must be inherent limits to how precisely events could be known" pg 136.
* Like Hannah said, predictions can only be statistical. All though the stats might lead you to believe one thing, there is still room for a different outcome (which is really reminding me of limits and discontinuity in calculus).
* "One measurement always made the other measurement uncertain." pg 136
All the stuff I'd say about Schroedinger has already been said. I agree that he has less impact than the other two.
These posts were extremely helpful since I had some trouble articulating exactly what these scientists did for the discipline. One thing I kept running into throughout tonight’s reading, was the word choice mixed with the subject. I would see words like individual, free-choice, and not-predictable all in the context of physics, which are words that I (personally) try to avoid when considering science. At first I was confused, but once I understood what Bohr was saying, I really appreciated that he acknowledged his own personal biased in his work. “It was a remarkable example of how science works and of the sense of personal authentication that science discovery can bestow. Bohr’s emotional preoccupations sensitized him to see previously unperceived regularities in the natural world.” (page 128) And, a couple paragraphs later as other people have already mentioned, “He famously insisted on anchoring physics in fact and refused to carry argument beyond physical evidence.” (Page 128) This seemed to me to be in exact contrast with how the scientists of todays movie/last night’s reading handled their discoveries.
Maybe I’m being stubborn, but I’m have trouble understanding how someone could argue that the quest for understanding what light is did NOT change science. I might be coming at that because I feel like…everything changed everything…but could anybody try to argue the other way? I’ve been trying to but I can’t.
The contributions of each of the scientists has been nicely summarized. I can only think of one thing I would add to this general pool of thought, which comes with a quote . "'There is nothing in the world which impresses a physicist more' an american physicist comments, 'than a numerical agreement between experiment and theory...'" (The Making of The Atomic Bomb, 127). Each of these scientists has contributed to the discipline of science in this way; they've worked to produce and prove material which is in agreement numerically between experiment and theory.
Ziz- I think one could argue that light did not change the discipline of science because of evolution and Hegel. Regardless of what the topic was (light, space, time ect...) we would have somehow taken these revolutionary steps that would lead us to how we define science today. We evolved through light.
I don't know if this makes sense, I don't really know how to articulate it, but it somehow makes sense in my mind.
There have been many excellent posts about the broad sweeping details each of these scientists have made. Thus, I will only talk for a moment on what I found most exciting.
Bohr made the point that there is a limit to what we can know and observe because we are using faulty and indirect methods of observation. Our instruments measure a few side effects of what is going on. We have no idea of the actual behavior of particles approaching the size of light.
He then takes this statement, and says that there is a base reality, and we try to model what we can see of it. The same thing can be made to look like to mutually exclusive realities if looked at indirectly.
I am thrilled by how clearly Bohr puts forward that there is a reality which we try to model and label.
Bohr's made significant contributions to the discipline of science, first of which was remodeling of the atom, "Bohr now proposed to lodge quantum principles within the atom itself" and pointing out the errors in classical physics. In regards to the atom Bohr revoltuionized the way people think by stating that, "…there must be what he called 'stationary state' in the atom orbits the elctrons could occupy without instability, radiating light, and without spiraing or crashing." (pg 124) This discovery was in direct contradiction to classical theory which stated, "classical mechanics predicted that an atom… would be unstable." Bohr follows the Hegelian tradition of moving forward towards something greater, newer, and possibly better
Heisenberg
Quantumn mechanics behaves randomely
Emphasis on Math
Accepting of the unknown
Schrodinger:
Math needs to be simplified in order to work within Quantum Mechanics
Sorry the last two were bulleted but it is 10:53 and i wanna make sure I get my post in on time!
Bohr is to me the first person who REALLY changed the discipline of science because he changed truth itself. In acknowledging the dualistic properties of light, rejected absolutism, which had been holding back History, Science, and Truth for forever. Things didn’t have to be just one way or most definitely this or that, he essentially unshackled, Science, History, and Truth by acknowledging that things aren’t black OR white, they can be black AND white etc.. “They could not be merged or resolved; they had to stand side by side in their seeming paradox and contradiction; but accepting that uncomfortably non-Aristotelian condition meant that physics could know more than it otherwise knew.” (138) Accepting contradiction and paradox leads to greater understanding. Different scientific methodology if you accept contradiction, contradiction doesn’t stop you in your tracks the same way. Different goals in Science, you are no longer trying to reconcile contradictory ideas evidence and theory. But like I said, Bohr really changed science because he changed truth itself. Truth is now ambiguous and has dualistic properties it isn’t this way or that way. If science is the pursuit of truth and understanding, then post-Bohr, what you’re pursing is fundamentally different and therefore science is fundamentally different. If you are hunting a turtle, your methodology, goals, process etc. is going to be different than if you’re hunting a panther. Science is to truth as hunter is to panther/turtle.
Bohr: "Bohr was happy to force this confrontation between the old physics and the new. He felt it would be fruitful for physics. Because original work is inherently rebellious, his paper was not only an examination of the physical world but also a political document. It proposed, in a sense, to begin a reform movement in physics: to limit claims and clear up epistemological fallacies." (p. 127)
Heisenberg: "Heisenberg decided to reject models entirely and look for regularities among the numbers alone... A few days more and he glimpsed the system he needed. It required a strange algebra that he cobbled together as he went along where numbers multiplied in one direction often produced different products from the same numbers multiplied in the opposite direction. He worried that his system might violate the basic physical law of the conservation of energy... He saw that he had "mathematical consistency and coherence." And so often with deep physical discovery, the experience was elating but also psychologically disturbing." (p. 132)
Schrodinger: "But Schrodinger, whose sympathies lay with the older classical physics, made more far-reaching claims for his wave mechanics. In effect, he claimed that it represented the reality of the interior of the atom, that not particles but standing matter waves resided there, that the atom was thereby recovered for the classical physics of continuous process and absolute determinism. In Bohr's atom electrons navigated stationary states in quantum jumps that resulted in the emission of photons of light. Schrodinger offered, instead, multiple waves of matter that produced light by the process known as constructive interference, the waves adding their peaks of amplitude together." (p. 134)
So, if I'm understanding this, Bohr delighted in original work. His glee in the metaphorical "sticking it to the man" harks back to Galileo's joy at disproving Sarsi.
Heisenberg did something pretty different from many and got rid of all practical models, all visual representations, and focused solely on the math. Then, to top that off, he goes on pretty much what amounts to a walkabout in Heligoland, and comes up with this crazy matrix algebra stuff that blows people away.
Schrodinger, even though Bohr and Heisenberg didn't truly believe in his work, came up with an interesting second option. What interests me most about Schrodinger's interaction with Bohr and Heisenberg is that it seems so.... jovial. I mean, Schrodinger is basically striding in and playing fast and loose with a lot of Bohr and Heisenberg's ideas. Yet they all have a bro-tastic weekend in Copenhagen, until Schrodinger gets sick and has Bohr's wife baby him. It just seems so.... amiable.
Of the three scientists, NEILS BOHR had the greatest impact on both the content of a major ranch of modern science -- atomic physics -- and on the larger conception of how science works. His first achievement was to take Max Plank's quanta, and Einstein's understanding of light as consisting of quanta, and not continuous waves, and applying them to the behavior of electrons. But his theory that electrons, upon the input of energy, could move evidently arbitrarily and unpredictably from one orbit or energy level to another, was deeply unsettling to classical physics. When he was challenged by Werner Heisenberg, from one direction, and by Ernst Schrodinger, from another, he finally developed, at Lake Como, his largest theory about how modern physics must operate. Both the wave theory and the particle or photon theory must be accepted as valid, but limited. They were complimentary, each effective in some contexts, and each setting a limit on the range of the other. Some physicists, notably Einstein, could never accept either Bohr's quantum theory or Heisenberg's uncertainty principle, but inststed, in Einstein's words, that God does not play dice. Bohr finally replied that men could hardly tell God how to manage the world, and stood his ground.
Werner Heisenberg was important for three reasons. First, he resisted Bohr's visualization of the structure of atoms, and insisted in trying to understand the ehavior of elecrons solely by the quanititative data that emerged from experiments. But this mathematical work strenghtened quantum mechanics, and he largely accepted Bohr's quantum theory. Finally, he realized that experimental oservation in subatomic physics had limitations that had not een encounered before in experimental science. To locate any particle, one had to arrest its motion, thereby distorting its velocity; to measure the velocity of any particle, one had to alter its location. The act of observing injected energy that distorted the results. So observation would always have some uncertainty, and the unpredictability of elecron movement at changing energy levels meant that nature would remain, at it smallest scale, knowable only approximately.
Finally, Schodinger tried to reject quantim mechanics entirely, and restore wave theory, and exact certainty, to atomic physics. His refined equations persuaded many physicists, but did not dissuade Bohr, Heisenerg, and others. At the same time, he prompted Bohr to concede some ground to wave heory, and to propose the theory of complimtarianism as the way that physics must move forward, emracing both wave and quantum theory.
When all the dust had settled, science had been greatly expanded, both in what it knew, and in the serious consideration of the idea that there were some gthings it might never know with certainty. This made Bohr's point, that science did not reveal exactly how nature worked, science only allowed one to see nature.
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. "'There is nothing in the world which impresses a physicist more' an american physicist comments, 'than a numerical agreement between experiment and theory...'" (The Making of The Atomic Bomb, 127). Each of these scientists has contributed to the discipline of science in this way; they've worked to produce and prove material which is in agreement numerically between experiment and theory.