martillo

For something with mass. Googling, that is the definition I find everywhere for relativistic momentum. Could you please give the definition for massless objects? I'm not questioning that electromagnetic waves have momentum. This is the wave-like behavior. I'm questioning how the relativistic concept of momentum applies to a photon. This is the particles-like behavior. I know the relativistic formulation of energy in terms of momentum you mentioned. I have just said that applying De Broglie law in the classical approach would give E = mc2.

The relativistic definition of momentum is p = mv for m = γm0v where γ = (1 - v2/c2)-1/2 and m0 the rest mass.

Really a good question. In Physics by definition something has momentum p if it has mass and velocity and the momentum is defined as p = mv. A massless thing (m = 0) would have then by definition zero momentum p = 0 and it also would have zero energy E = 0. I agree with the OP that there could be a real problem in the subject. Considering the "wave-particle duality", the wave-like behavior of a photon gives a frequency f and an a wave-length λ = c/f to it. The Planck-Einstein energy formula for a photon gives an energy E = hf to it and we can deduce: E = hc/λ. Now, considering that the velocity of a photon is c, the De Broglie law would give λ = h/mc for a photon and so we would obtain a mass for a photon satisfying hf = mc2. A photon would have a finite mass m = hf/c2. The problem is with Relativity Theory. In Relativity Theory photons must be massless but there is that problem with the definitions of momentum and energy...

I know that but if you have something that is partly determined and partly indetermined as a whole it is indetermined. I already told you that what is presented there is about fast processes only that can be called intuitive ones. You must consider slow enough processes where rationalism is present before making a choice or decision. We already discussed about this in the other thread. I will not just repeat the discussion here.

Those prohibitions are not enough to make the physics of the universe completely deterministic. There still are nondeterministic processes which make it indetermined. Analogies not always work... Quantum Mechanics is then a big model in Physics and it tell us about uncertainty in the universe and so its indeterminacy. All the guaranteed data in the past is not enough to completely determine the future of some processes. That's why indeterminacy takes place.

Essence meaning (googling): "the intrinsic nature or indispensable quality of something, especially something abstract, that determines its character." That goes for you too. I mentioned you would have to demonstrate your determinism confronting Quantum Mechanics uncertainty. You also have to demonstrate that choosing is just an illusion of our mind.

Of course they do. It's the same system, and the future is just an as-yet unrealized past. The state of the future will be the result of the present and past. There is no difference here. The problem is more about insufficient information to feed better forecasts than it is about impossibility, but scale of course matters. I may not be able to tell you where each individual raindrop will land, but I can tell you with great precision how much total rain will fall in the week ahead. No. It is not about predictability of the future. It is about its nondeterministic essence. As several ones posted, Quantum Mechanics definitely "knocked out" determinism in the universe. You would have to demonstrate the contrary. I just say that the indeterminism in our choices or decisions is also another source of indeterminism in the universe. But you (as Dennet) say that choosing is just an illusion of our minds. I'm not able to demonstrate that for now. I just can say that I don't believe is just an illusion. Not able to discuss about. Anyway, "QM definitely knocked out determinism". Unless you demonstrate the contrary of course...

Seems I didn't get your point then... You say hind-casting is used to check/test hypothesis. Seems you are talking about the scientific method to validate hypothesis then. I think the method is valid for deterministic processes only, not for nondeterministic ones.

Hind-casting is used in predicting clima for instance. Is clima well predicted? I think is not the case. Fails too many times.

I must point out that the key point of the discussion is about determinism/nondeterminism of the future. While the present is determined by the past they both do not determine the future. I mean that looking at the past we can always find the events and chains of events that leaded to the present but looking to the future not all the future events are completely determined. Not only there is "quantum inndeterminism" in some future events but also your future choices or decisions cannot be completely determined. Looking at the past when you made a choice, If I ask you what caused your choice you can always answer me the reason of the choice. Looking to the future not even you can answer about all of your choices in the future. The future has some degree of uncertainty. The future is undetermined. Is the case of Indeterminism.

Seems to me now that the category associated to a member (displayed just below the nickname) is more related to the net number of likes received than the number of posts made and curiously negative ones count the same as positive ones...

I do, however, would like for somebody to address this. I would just comment that I don't know how words and images are actually stored in the brain and less know how the process of thinking with them takes place in the brain. As I have said, how actually the brain thinks is actually still a mystery for me.

Seems it is not the case you mention. Just at Wikipedia it can be found at the very beginning of the page https://en.wikipedia.org/wiki/Libertarianism_(metaphysics) the following: "Libertarianism is one of the main philosophical positions related to the problems of free will and determinism which are part of the larger domain of metaphysics.[1] In particular, libertarianism is an incompatibilist position[2][3] which argues that free will is logically incompatible with a deterministic universe. Libertarianism states that since agents have free will, determinism must be false and vice versa.[4]"

I mentioned "elbow room" just because it appears in several articles about the libertarianism approach to "free will". For instance at Wikipedia: https://en.wikipedia.org/wiki/Libertarianism_(metaphysics) I have found it defined as "space to move". I associate it to "degrees of freedom" to make a choice in some situation.

@studiot didn't answered that yet. I think there is some indeterminism even in purely physical phenomena. If you would prefer to stay on physical determinism/indeterminism I would propose to analyze the "quantum tunneling" phenomenon for instance. As far as I know there could be only a probability for an electron trespass a potential barrier through "quantum tunneling". I mean, actually a particular electron can undergo through "quantum tunneling" or not. There would be just a probability for it to do that. It doesn't mean it will do that. Wouldn't "quantum tunneling" be an inherently nondeterministic phenomenon? If some inherent nondeterministic phenomena actually do exist I conclude that is the case of Indeterminism and not Determinism in the universe.

May be you are referring to myself. I'm the only one here defending the "libertarian" current of philosophy on the subject in which "free will" and "determinism" cannot coexist at the same time. They would be mutually exclusive. What I point out is that there are deterministic situations sometimes and nondeterministic ones other times with some degree of freedom only because total freedom actually never exist. What I defend is that as there are undetermined situations sometimes the future is not determined and so as a whole is the case of "Indeterminism" and not "Determinism". I think all the discussions in the forum in all areas are about the real things in the world and in the universe and not how we would like them to be. I just say there are both, deterministic situations and nondeterministic ones and that because of the undetermined ones the future is actually undetermined. This has nothing to do with good/bad subjective perceptions.

No, I will not enter in such level of doubtfulness. Useless discussion, waste of time...

May be you could rephrase your question with the key point you are considering which I don't get.

I thought in an example showing volition with enough "elbow room" proving indeterminism in the future. A sad story. Uruguayan flight 571 through the "Andes" mountains to Santiago-Chile crashed. Many people survived at the crash in the high mountains although some seriously injured. They had a radio receiver telling a rescue operation was initiated looking for them. After seven days the unsuccessful rescue operation was cancelled. They were considered dead in the mountains. The situation was to decide what to do then. Different people took different options. As time passed some stayed waiting for rescue surviving through cannibalism. Some departed walking through the mountains. Someones refused to eat Human flesh and died. Finally after more than two months the departing ones found help and the ones still surviving at the mountains were rescued. The case shows a situation with different choices made by different ones with different results well showing the future was undetermined for the passengers at the crash. Their future was undetermined for them at the situation and depended on their decisions and other things like their injuries, avalanches happening, etc. I think the sad case is a good example of enough "elbow room" in a situation showing an undetermined future for someones. I think is clear that the future is not determined and that actually indeterminism takes place. PS: Books and films have been made on the story.

May be? Do you doubt? Definition of choose (just googling): "pick out or select (someone or something) as being the best or most appropriate of two or more alternatives." Just some few cases when we do make choices: menu in restaurants, political elections in real democratic countries, choosing a professional career... Volition does exist or do you think is doesn't? The problem of how we make a choice in terms of our neuro-biology is another subject...

Seems life is involved in the subject. Only living beings can make choices or decisions. Without life the universe could well be deterministic but seems life changes the things.

It could be all about the "elbow room" we can have sometimes. If in the future we do have enough "elbow room" the future is undetermined. The hard problem is in how to demonstrate enough "elbow room" could actually exist sometimes...

So, the key point is about the "elbow room" in our future choices/decisions. The "elbow room" in the future... I believe it could exist sometimes but how to demonstrate that, I don't know. May be I could think in some example and that would be enough. I must think about...

Yes in Spanish the term "determine" has some different meanings but I think we must focus in the context of our discussion and give an appropriated definition to it. I'm considering the mathematical concept of determining which is the used one in Physics and software/hardware Computing: _ The value of a function is determined by the values of its variables. _ The inputs determines the output. Sure. Our problem is now is if at some present state the future can be determined by things of the past only and not by other things in the future. The thing is then related to if our choices are deterministic or not. If our choices depend on things in the past only then they are determined and the future could be determined. If our choices are not deterministic then the future cannot be determined. This is in what our discussion is centered in this thread I think. Seems the problem is about the "elbow room" (or degree of freedom) we can still find in our decisions in that future. If in the future we still have an "elbow room" then we can either play dice, rationalize about the best choice or just intuitively "follow our heart" for us to finally make a choice and decision. In this case there would be some indeterminism in the future choices and so in the future.

The thing became complex for me now. While I intuitively agree with libertarian free will I find really complex now to rationally demonstrate that is really the case. I'm studying deeper the subject but I think I will not reach to a final demonstration. The literature actually present different philosophical currents with their own argumentation but there's no final conclusion of one be true while the other ones being false. The subject has remained unresolved for very long time. I don't pretend now to be able to solve the it on my own. On another side I feel cheated with the Stephen Hawking quote I have presented. Actually he wasn't defending "free will" as I believed. That quote is just the beginning of a larger reasoning: "I have noticed that even people who claim everything is predetermined and that we can do nothing to change it, look before they cross the road. ... One cannot base one's conduct on the idea that everything is determined, because one does not know what has been determined. Instead, one has to adopt the effective theory that one has free will and that one is responsible for one's actions. This theory is not very good at predicting human behavior, but we adopt it because there is no chance of solving the equations arising from the fundamental laws. There is also a Darwinian reason that we believe in free will: A society in which the individual feels responsible for his or her actions is more likely to work together and survive to spread its values. (pp. 133-135 Black Holes and Baby Universes and Other Essays (1993))" I have found that the true quote of Stephen Hawking on free will is in his book "The grand design": “It is hard to imagine how free will can operate if our behavior is determined by physical law, so it seems that we are no more than biological machines and that free will is just an illusion.” Time for me to review many things. As for now I just can say that I intuitively agree with the libertarians' philosophic current...