acespenlaub

Members
  • Posts

    9
  • Joined

  • Last visited

About acespenlaub

Previous Fields

  • Full Name
    asdfghjk

Recent Profile Visitors

2,324 profile views

acespenlaub's Achievements

Newbie

Newbie (1/14)

0

Reputation

  1. I apologize for dredging up an old thread but no one responded to the last post -- and I think it hit upon something supremely important. That there is "a world out there independent of our will or our presence" is indeed philosophy, especially on this forum!!! It is a statement of Objectivist metaphysics and the primacy of existence. That is, that Existence Exists, over and above the existence of a consciousness to perceive it. What Ba'al consistently rails against as "philosophical prejudice" is simply the frequency with which so-called philosophers get that bass-ackwards, and apply their incorrect metaphysics to science! Despite almost every philosopher throughout all of history having had it wrong, it doesn't mean that the right answer isn't philosophy as well, when it comes about. It would be like not calling Special Relativity physics because up until that point no physicist had been right about the limitations of Galilean Relativity. It is important to agree on definitions before beginning an argument because if two people are having a discussion, but insist on using different definitions of the same words, then they will get nowhere. Therefore, it is still necessary to distinguish philosophy as the study of the fundamental nature of knowledge, and reality from philosophy as the collection of ideas promulgated by all the philosophers that have so far published their ideas. The former is the sense in which most people on this forum, I suspect, use the term philosophy, and the latter how Ba'al has been using it. The only reason to shun the former definition is for fear that the person you are speaking to might accidentally confuse the two and automatically write off as lunacy what you are saying, simply because you called it philosophy. I hope this post will have helped to guard against that possibility, so that we can all stop bickering over the meaning of the word and get on with real and thought-provoking discussions of fundamental science --Andrew Espenlaub
  2. After mulling the deBroglie-Bohm style interpretation around for a bit (and taking some final exams ), I have some comments on it. First, I want to state the general idea so that we can make sure we're all on the same page and I'm not misunderstanding it. Instead of the wavefunction being the "particle," there is instead a point particle being transported around by a wave whose shape is given by the wavefunction. If that's all correct, then there is a problem with energy transfer. If the "particle" in the traditional picture has 1MeV of kinetic energy, then in the dBB picture, the point particle will have to have the energy, since otherwise a spot appearing on a screen in a double slit experiment would not be explainable. But then what is the pilot wave? Waves are disturbances and so must carry energy. If they were disturbances which didn't have a different energy than the system without the wave, then you can't rightfully call them disturbances. So where did this energy come from in the dBB picture? What created the disturbance and gave the wave its energy? Is there just a sea of energy-carrying waves filling the universe that we can't tap into, except to see their effects on point particles they've transported around? What is the nature of the interaction between the particle and the wave -- can they transfer energy between each other? If they can, then can you ever observe the change in energy of the particle? If they can't, then there is no interaction, so how does the wave move the particle around? Also, this criticism is particularly damning, because it shows how the dBB picture is essentially a "many-worlds" interpretation -- and for there to be "many-worlds" none of which we can interact with at all except our own is a contradiction in terms. Existence is a mutually interacting set of things and something which cannot interact with anything cannot exist! --Andrew P.S. - Stephen, I think the video is of an actual demonstration, since the narrator refers to a monitor showing the pattern. Also, E&M with Jackson is next term...I can't wait.
  3. Dennis, I see now what the major issue is here. It is in the interpretation of "probability." In the classical sense, probability implies hidden knowledge -- information that the observer lacks, but could collect if they spent enough time at it. The underlying metaphysical assumption here is that the process is deterministic and the observer just doesn't have all the facts (but could). In the Born sense, there is no hidden knowledge...at least not in the sense of anything knowable. The probability is inherent in the metaphysics. The observer has all the facts, but can't avoid the probability because it is essential. In both cases, the probability looks the same to the observer, since it is either essential or the observer doesn't have all the facts. That is what I meant by "fundamental probabilistic behavior" and it was careless on my part. Check out his video to see the experimental proof that things at least look probabilistic -- The uncertainty principles prevent us from ever reaching an experimental precision which would allow us to refute the essential probability view, so the only recourse for settling the question is rigorous analysis of the metaphysics. (*Note: the uncertainty principle comes from the mathematics and has nothing to do with calling a particular mathematical object a "probability"). Since you think the deterministic approach is right, would you care to offer a metaphysical counter-example to the essential probability view? Perhaps we can work it out here (or in a new Metaphysics thread). I'd be more than willing to play devil's advocate and take the essential probability view, for argument's sake. --Andrew
  4. Ba'al, I never questioned that the interpretation of quantum mechanics is open and never claimed that the probabilistic view is correct. It is an interesting topic to think about and a friend and I are going to ponder hidden variable theories over the holidays. So thank you for posting about them -- I have been meaning to spend some time digging through the existing literature but it keeps getting pushed aside. Other than reminding us all of an interesting debate, I'm not sure if your post was intended to further the discussion. If it was then you should note that von Neumann was wrong about the impossibility of hidden variable theories, but that says nothing about the Spectral Theorem. So, once again we have the distinction between the physics and the interpretation. The interpretation requires metaphysical insights to get right, where as the physics (such as the Spectral Theorem) does not require them...at least not as directly. --Andrew P.S. -- Adam, I have played some but haven't spent much time on it recently. It would be fair to say I'm terrible at the moment!
  5. Selene, I never knew that about the etymology of 'metaphysics.' I always took it to mean the knowledge we need to understand the physical world beyond physics -- and not the stuff that Aristotle wrote about after physics. --Andrew P.S. - No, I'm of German heritage, but I'm studying Italian and love the food and language. I mostly play computer strategy games now because it is much easier to find opponents and the rules can be much more complex, while at the same time remaining easy to play. As a kid, I did play quite a few board games with my dad, some of which were not easy to play (e.g. - Caesar and the Battle of Alesia ).
  6. Mike, Thank you. And yes, sadly that is true. But at least we can try to get the facts straight, so that we at least have more ground to stand on than our opponents. --Andrew
  7. Thank you Stephen. Ba'al, do you think that philosophy and physics should be competing with each other? That they are mutually exclusive? In fact, physics used to be a branch of philosophy, back when the sciences were collectively called "natural philosophy." Philosophy at the time simply meant, as it does in the original greek, "love of knowledge/learning." So, in a sense, after 3000 years philosophy has given us quantum physics!! You should keep in mind that metaphysics, which is a branch of the field of (modern) philosophy you denounce outright, is much more broad in its scope than physics. It says nothing of the nature of things, only what it means for those things to have a nature. Both metaphysics and physics are necessary to understanding the world around us. You are correct that physics can be done successfully without any substantial amount of explicit metaphysics, but that is only because they ARE DIFFERENT THINGS! It's like saying that history can be done without doing organic chemistry, and then going on to bash organic chemistry. The interpretation of the physics must include metaphysics because "what does it mean?" as a question must always lead back to philosophy. You're right that you don't need a lot of philosophy to do good physics but to do good metaphysics, you need to interpret the physics! --Andrew
  8. acespenlaub

    Welcome

    Hello everyone! Just posted in a thread about the philosophy of quantum mechanics and figured I should introduce myself before I post anywhere else since this seems to be a "first-name basis community." My name is Andrew Espenlaub, I'm 21, a senior at the University of Pittsburgh studying physics. I am taking my fourth graduate course now and three more next term and have three-and-a-half years of experience working in a research lab as lab manager/experimenter (that's for potential employers ). I have been a life-long Objectivist though for most of it I didn't know that was what you call it. I just sort of decided that religion and duty and such things weren't rational and discounted them. Imagine my joy when reading OPAR for the first time! It made explicit many of the implicit beliefs I had held and gave me more solid ground to stand on when making decisions. I have a broad range of interests across the humanities and sciences, but focusing on work and school leaves me little time to devote to serious study of anything else. Recently I have met several other objectivists at UPItt and they have become instant friends. Discovering a whole forum of people who share my dedication to rationality and familiarity with Ayn Rand's philosophy is sure to lead to many many many interesting discussions and I can't wait!!!! --Andrew
  9. This discussion could benefit from another person who is familiar with the mathematics of quantum theory I think. First, physicists should not relegate metaphysics to the "domain of the irrelevant!" It is a necessary tool for developing the correct conceptual interpretation of a theory. However, as quantum mechanics shows, it is possible to construct a marvelously precise and accurate theory using mostly physical facts and mathematics. What the implications of this are to the ultimate nature of the universe lies in the metaphysics however! Everyone needs every branch of philosophy, even physicists. If you don't agree with that, why are you posting on an Objectivist forum? Second, to explain how quantum mechanics can be so successful but still have absolutely no metaphysically acceptable interpretation as of yet, I need to talk a little about the mathematics. Nothing obtuse, just the broad concepts: There is an amazing theorem called the "von Neumann Spectral Theorem" which is at the very heart of the success of quantum theory. In essence it states that any set of real numbers can be associated with a mathematical object called an "Hermitian operator on a Hilbert space." The mathematics of such objects and the objects upon which they operate in the "Hilbert space" is well developed, largely as a consequence of quantum theory. The power of this (proven) theorem is that any observable quantity, any measurable property, has a set of possible (real, not complex) values and so simple enumeration of these values allows us to immediately apply the mathematics of "Hermitian operators." This is would give us the same result as classical dynamics gives us if the measurable values were continuous -- that is for any two measurable values, there is always another one in between them on the number line. However, experiment shows that for some phenomena, some observable quantities have a discrete set of allowable values such as {1,2,3,...} and not the numbers in between. This discreteness leads to ALL of the distinctly quantum stuff in quantum theory. In addition to discrete sets of measurable values, we observe that physical entities at small scales are actually impossible to localize to a specific point in space. That is, every "particle" metaphysically can be said to be everywhere at once. The usual analogy is that of a water wave -- it is something which exists across the whole surface of the lake/pond/pool/etc.... Like the water wave, "particles" are not uniform across space but have a property which varies spatially. The interpretation due to Max Born takes this property and associates it with the probability of an interaction with another particle. This probabilistic behavior CAN BE OBSERVED in experiments involving the diffraction of very low intensity particle beams. If you shine even moderately intense light (which is as much a particle as an electron or neutrino) through a narrow slit, it will produce a pattern of light and dark on photographic film placed opposite the slit. However, at low intensities the pattern is slowly built up over time on the film by individual light particles hitting the screen. Where they hit (and where spots appear on the film) can be described by the Born probabilities. This is the same slowly emerging pattern that appears when you plot the results of rolling a die. Though you may roll a lot of 6's initially, eventually, each side will be rolled an equal number of times -- but the pattern takes time to appear. The question is then, not one of the metaphysical status of fundamental probabilistic behavior, non-locality or discreteness of measurable values, but what these experimentally observable FACTS mean metaphysically. What is the true nature of existents which gives rise to these non-common sense properties? What seem to be the two main points of contention in this discussion are therefore resolved: 1. Yes, philosophy is important in interpreting physics, but you must be wary that the things which you give the status of metaphysically fundamental are not in contradiction with experimental fact. And do not throw out philosophy altogether because someone else's philosophy (or the bulk of humanity's philosophical thought) is at odds with experimental fact. It just means that most philosophers are flat out wrong, not that proper philosophy isn't useful. 2. The central question concerning quantum mechanics is not whether fundamental probabilistic behavior or non-locality are metaphysically possible, because they are in fact experimentally verifiable, but rather, it is what do those observations imply about reality outside the realm of common experience. Both sides of this discussion were right on one of these points and wrong on the other. This was partly due to the ineptitude of most physicists at grappling with quantum mechanics AND metaphysics (thus a lack of available, useful information to non-specialists), and partly due to needing to check one's premises. If I have misstated any facts or am ambiguous, please comment to that effect -- this is important to get right because quantum mechanics is unfortunately the source of much of the new "philosophical word salads and b.s." and having the right answer is the easiest way to discredit the wrong ones. P.S. -- Richard Feynman was a brilliant physicist but tartness does not imply correctness. He didn't have the right answer and was tired of hearing wrong ones so he told people to give up trying to provide an answer. At least then no one would be wrong....