Hot answers tagged

58

Complex numbers are not, as you suggest, "...an integral part of physical reality". Neither, as you say, does the "quantum wave distribution function necessarily uses complex numbers". Not necessarily. Quantum mechanics can be mathematically formulated using the real numbers, the complex numbers, or the quaternions. See, e.g., https://arxiv.org/abs/1101.5690 ...


30

First of all, I would caution you against using definitions from Wikipedia when considering serious issues. I'm not a physicist, but I'm sure that the appropriate people could give you pointers to places where serious physicists have weighed in on the proper definition of "energy" and "force." (I seem to vaguely recall Feynman dealing with this in his ...


20

The short answer: Your premise is not correct. Quantum Mechanics is not necessarily complex-valued. Here is a primer from Physics.SE if you are solid on the math. An explanation that is light on math: Complex numbers represent a particular collection of symmetries that behave in a particular way. They happen to be closely related to Real numbers because ...


16

Hawking's claim seems reasonable. It was not until the later part of the 19th century that "philosopher" meant philosopher of philosophy. Most so-called contemporary philosophers (the academics) seem to be historians of "philosophy," and they seem content to read, re-read, re-re-read Plato, Aristotle, Kant, Hegel, etc.. The irony, of course, is that no one ...


15

The trouble with considering Einstein (or any other intellectual genius) a philosopher (or an expert in any field in which they did not establish themselves) is that it's difficult to separate their reputation from their accomplishments. Strictly speaking, Einstein was both a lover of knowledge (the literal meaning of "philosopher") and a deep, effective ...


14

Your question is about metaphysical realism and skepticism. There are indeed radical sceptic arguments against realism such as Descartes's demon, brain in a vat or the idea that one is actually dreaming, but also reasons to resist these arguments. First note that there can be no empirical evidence for or against such radical scepticism because these ...


10

According to John Burtnet, Thales believed that: The earth floats on the water. Water is the material cause of all things. All things are full of gods. The magnet is alive; for it has the power of moving iron. Aristotle said, in De Anima: Certain thinkers say that soul is intermingled in the whole universe, and that it is perhaps for ...


9

I think one source of confusion with the concept of time is that it actually names two very different but related concepts: The qualitative concept of time as an experience. The objective physical phenomenon underlying that experience. To make clear what I mean, let's look at a different concept where this separation is generally understood and where we ...


9

A universe having a finite volume can be unbounded in length and have unbounded cross-sectional area. The example I have in mind is mathematical, not physical. It's called Gabriel's Horn. It's a standard example in first-year calculus. It's also called Toricelli's Trumpet, after Evangelista Torricelli, a student of Galileo. His discovery of this strange ...


9

The view OP is alluding to is called mereological nihilism (mereology is a branch of metaphysics that studies relations between parts and wholes). It is the view that only "simples" (fundamental entities) exist, and composition of simples does not give rise to new objects. Applied consistently this means that, strictly speaking, not only time but chairs and ...


8

It merely comes down to how one defines philosopher: liberally in that anyone who thinks about knowledge and wisdom? Or specifically as in someone who has studied philosophy somewhat extensively, perhaps having degrees in the field? (This is what Jon & Eric appeared to be equivocating on.) It appears the OP's particular definition regards the usage of ...


8

Well, certainly he should know enough not to make foolish statements like the one above. Since science (and thus physics) is based upon the principle of controlled observation, a good knowledge of epistemology would seem to be de minimis; I suppose that a phenomenological approach seems appropriate to me, but that might be getting too prescriptive. ...


8

Certainly. Simply because one cannot both know position and velocity through measurement, for example, doesn't prevent the idea that if one did know both, then they could present with certainty the outcome. One might suggest a metaphor: if you were trying to aim a cannon and you measured exactly one of the angle of inclination or the amount of powder in the ...


7

We can't be sure. Just as we can't be sure that we aren't living in some giant computer simulation of our universe. Each of these cases would feel exactly as real as if the universe was real and as if it has existed for at least 13.7 billion years. Physics and science discovers truth by testing falsifiable hypothesis. So a hypothesis that is not falsifiable ...


7

I would suggest that one way to distinguish cause from effect when the two are simultaneous is through material implication. That is, if at some time two events A and B occur, the cause is that one which implies the other. So, if A being true means B must be true, then A is in some sense the cause of B (I realize that the whole correlation versus causation ...


7

I think it is very insightful of you to want to learn to be a better critical thinker. That action in and of itself makes me think you are already more of a critical thinker than many others -- as merely a freshman you are carefully thinking about and planning what will best help you in the future. Not the Answer You're Looking For Unfortunately, philosophy ...


7

Are Why-questions "fundamentally metaphysical in nature"? No. Bas van Fraassen is a prominent example of a recent philosopher who understands scientific explanation as answering Why-questions, and who is also an fairly strict empiricist, meaning that he does not think science has access to nature beyond what is observable. See his The Scientific Image for ...


7

1st premise : No body can have a force contrary to inertia. Based on [Engl.transl.,page 2] analysis of "current" (still quite incomplete) understanding of matter and bodies and of knowledge of only a few of their properties. The first property that comes to mind is extension; all philosophers recognize it as a property of body, and Cartesians consider it ...


7

In my opinion you are mixing up different points: Physics does not use complex numbers to count entities. It is sufficient to count mangos by non-negative rational numbers, i.e. 1 mango, 1.5 mangos, 1/3 mango etc. You are right that quantum mechanics is based on the psi-function which is a complex function. The squared modulus of this function, a real ...


6

Nothing at all. This is the same base idea at the heart of non-inertial reference frames. This is like Einstein's claim (at the heart of his idea that grew into relativity) that it is impossible to distinguish between an accelerating frame or reference and an inertial frame of reference in a gravitational field. That is to say that if we are in an elevator ...


6

The finite speed of light puts the whole idea of simultaneity into question. For example consider a person A standing in a field halfway between two poles (A+B). He sees a lightning bolt hit each pole simultaneously. He thinks it's simultaneous. Now person B is standing closer to one of the poles (B) than the other. What does he see? The lightning strikes ...


6

We do not perceive time, of course. What we do perceive, albeit indirectly, is change: we see one situation, form a memory of it (or retain it in our short-term memory of what's happening), and then perceive another situation which differs from it. The notion of time is prompted by the notion of change; and the notion of a regular "flow" of time comes from a ...


6

This is a particularly sticky wicket because (a) we are delving into the philosophy of quantum mechanics (which is beset on all sides by those who wish to pervert it to their own ends) and (b) because we are confounding our understanding of the problem by confusing what we mean by "exists." To make this question more meaningfully answerable I will address ...


6

I've found in Norman Wentworth DeWitt, Epicurus and His Philosophy (1954), page 163 : Lacking a unit for the denotation of extremely high velocity, Epicurus describes it as follows: "Furthermore, motion through the void, so long as no interference arises from conflicting bodies, accomplishes any conceivable distance in a space of time ...


6

Look at what Peter van Inwagen says in his book "metaphysics" (an excellent read) on this issue. He accuses physicists who claim to have solved the philosophical problem of origin or creation of conflating the notion of "philosophical nothingness" with "physical nothingness". The problem with many answers from physics, as @infatuated pointed out, is they ...


6

One of the fundamental principles of quantum mechanics is the principle of superposition. Its most simple application reads: If two paths exist to move from state A to state B, then the transition function (psi-function) develops to the final state as the sum of the two separate transition functions. The double split experiment has two different paths from ...


6

In my opinion, the best response to ontological uncertainty is to strive to live in a way that is meaningful regardless of the true nature of reality. While it may seem implausible, it may be less so than it seems. Consider the following --we don't know how our universe originated, we don't know what its fate is, we don't know with any certainty our own ...


6

The problems of motion and gravity were philosophical problems before the scientific revolution. People followed Aristotle's teachings. https://en.wikipedia.org/wiki/Aristotelian_physics Look at how Aristotle described motion and gravity. There's no mathematics involved... no empiricism really. It's all argued from first principles, starting with all sorts ...


6

A science is a well-defined systematic way of organizing and extending a body of knowledge. What makes it a science is its reliability, not its subject. Philosophy explores subjects that are outside the realm of science, which is to say, that do not have a well-established, reliable, systematic way of approaching them. Your lecturer is stating that when a ...


Only top voted, non community-wiki answers of a minimum length are eligible