Eise

You said: That what you call 'philosophy of how to build an atom bomb' is just a higher level description of how an atomic bomb works. It explains the basic physical principles of the atomic bomb. It is definitely not philosophy.

I think the problem is that many physicists think about old fashioned, classical metaphysics. If you read a history of physics (and/or astronomy) you partially read about the same bunch of people as when you read a history of philosophy: Thales, Heraclitus, Plato, Aristotle, ..., Kant, just to name a few. There we have explicit 'explanations' about the physical world, and in the light of modern physics they are mainly wrong. On the other side, there are philosophers who seem to think that they can talk about physics as peers of real physicists. That can cause some irritation with physicists of course. And then there are the irritations here in the thread, and having a background in philosophy and in physics (a background, @MigL, I am definitely not a physicist (as I use to say, I am at most a 'half-cooked physicist')), I would say that beecee does not understand what exactly you are aiming at. Again and again he comes with the same (kind of) 'bon mots' about philosophy, that are taken out of context (Russel), are just nice sounding one pointers (Shaw), or have themselves no idea what modern academic philosophy really does (Krauss). @beecee, for all clarity: Davy is not aiming his arrows at science itself; they are aimed at its self-understanding. And this self-understanding is hopelessly naive in the 'shut up and calculate camp'. The other camp, that of the 'what is it exactly all about camp' have an inclination to become philosophers: reflecting on basic premises and methods of their science, eventually developing new concepts or methods. And there philosophers can learn just as well something from these kind of physicists as some physicists can learn something from philosophy. It's not all just black and white.

Really? I know a little philosophy and physics. Enough to recognise crackpots in both disciplines. And where Krauss surely is a good physicist (cosmologist?) at the terrain of philosophy he is a crackpot. Of course I stumbled over the few lines where he talks pejoratively about philosophy. But by the quality of the arguments, one recognises the value of these remarks: none. If you do not like semantics, then philosophy is definitely not your thing. So it once was true that sun orbited earth? But when it was true, i.e. a perfect fitting model of reality, then once the sun really orbited the earth. And it stopped at the day Copernicus came with his heliocentric model? Davy (and I) are not confused. We see how complicated it is to give a correct account what happens in science. And as said earlier, I believe that the problem is grounded in the difficulty to account for the relation between language and 'reality', i.e. what is talked about. I am not 100% sure if I can also speak for Davy, but it is not about the praxis of science, the value of its insights, or its undeniable value for developing new technologies. Science works, that should be clear. It is about the selfunderstanding of science. Do you know the true nature of anything? (I am afraid I don't). I think a better criterion for'approaching the truth' is the increasing domain of theories: Ptolemy was OK for predicting celestial observations (but we would never have been able to send New Horizons to Pluto...), with Kepler the picture was greatly simplified, with Newton a connection with earthly phenomena was made (same explanation for falling objects and orbiting celestial bodies), and Einstein, making gravity Lorentz invariant (if this is a good description of GR) was even able to predict new phenomena. What we see is continuing extension of the domain of application theories. One could say, the more encompassing a theory is, the better it is. But if that means that we are 'closer to the truth' would suppose that we know there is some truth out there (how would we know that) and we are closing in. Another kind of example: we have a very extended theory of the electron. We know how it behaves in all kind of situations. It might be that there is nothing more to add to it. Suppose this is the case, do we then know the true nature of the electron? I would translate that, conform my musings above, that we know we do not have a complete theory of gravity: GR fails for the centre of black holes and the big bang. But when we have one (empirically validated), would we then know the true nature of gravity? Or are we a bit more humble, and say we have a pretty good understanding of gravity, because we can calculate through every possible situation we know of in which gravity is essentially involved?

Hmm, I do not think so. Physicists solve physics problems, philosophers philosophical problems. However, sometimes physicists stumble on limits where they do not come further (best example is the beginnings of quantum physics). That means it are physicists themselves who 'go philosophical'. Questions about reality, objectivity, what measurements are etc come up. At that point physicists might find it useful to have some overview of what philosophers have to say, or maybe even better, just have some philosophical training. But philosophers saying what physicists have to do is not something they are waiting for, especially not of philosophers who have no idea about physics (oh yes, during my study philosophy I heard the most abstruse ideas about physics from my fellow students. Not so much from teachers/professors, luckily enough)). But just hear what post-modernists have to say about science... Just in support of Davy: truth belongs to the very definition of knowledge. In this case I have to agree mostly with Davy. There is a, maybe unsolvable, tension between what scientists do, ('acquiring knowledge') and their understanding of it. My educated guess (therefore the 'maybe unsolvable') is that it might be impossible to understand the relation between language and 'reality'. I would not say 'overlap', even if the border between science (do not just think physics here) and the 'philosophy of that science' can be vague. That is definitely not philosophy. Different topics, y'know. What you seem to mean is that there are higher level descriptions which do not suffice to actually build an atomic bomb.

Hi Studiot, yes, I was intentionally a bit short, because dimreepr does not like long answers (Oh, am I mean...). I once wrote a long post about what philosophy is, maybe I'll try to find it again. Edit: found! I think it is not a question of detail. But with the 'core/underlying principles' you surely have a point. (Yes, I left out 'broad'). I don't know, so let's ask a question: 'Who was the head master of Hogwards, when Harry Potter became a student there?' If you know, you have at least some knowledge of Harry Potter. You see, for the question to make sense, you have to take the context into account. And the context is a story. But because the story is well known, and published, above question can be answered. Well, every discipline (I prefer that above just 'science': there also is theology, morality, as you notice) has its own basic methods, beliefs, and problems. When people are reflecting on that, they are doing philosophy.

Of course, but it is not strange. When a well known physicist makes such denigrating remarks about philosophy, where it is clear as day that Krauss knows next to nothing about what is actually happening in academic philosophy. From a philosophical point of view: no. For those interested in cosmology, of course, it is a good read (yes I read it). beecee, to understand the qualities of philosophy you must know what actually is being done at philosophical faculties. And to be honest, I think you have no idea. I am afraid Davy_Jones is exactly on point: knowledge is commonly taken to mean 'justified true belief'. So false knowledge does not exist. What exists is people believing they have knowledge, and which turns out to be mistaken for knowledge. What Ptolemy beautifully shows: to make precise predictions of solar system events, Copernicus was a step back. So he had other grounds postulating his heliocentric model. Only when Kepler, based on precise astronomical observations by Tycho Brahe, came with his ellipses, the predictions really improved. So, no. You confuse 'having knowledge' with 'believing to have knowledge'. Nope. Given the definition of knowledge (justified true belief) false knowledge is a contradiction in terms. 'False beliefs' exist, but not false knowledge. I think it really would be interesting to go into detail about the Ptolemy-Copernicus topic. Why do we say Copernicus' view is closer to the truth than Ptolemy, whereas the concrete predictions that followed from Ptolemy were more precise than those of Copernicus?

The topic, of course. When it is no offense, what is it? I always wonder how physicists could say philosophy is useless, during them making philosophical remarks or ponderings. Take the famous Feynman video about 'what is magnetism'. He nearly does not talk physics: instead he is pondering what such 'what is ...' questions factually mean, and what physics can say about it (not what physics says about it). In another video he explains the role of experiment in science. But that is not physics either. So what is it? To give a hint: it starts with 'ph' but ends with 'y'... To repeat my disclaimer: Maybe it is a bit too harsh: I think the great minds examine this philosophical baggage, can explain it, maybe even justify it. Feynman is a fine example, even where he ridicules philosophy. It must haven been the quality of the philosophy lectures he visited.

I read the sentence as 'Dennett discovered that it is impossible to explain consciousness to people without a spiritual basis'. To say that Dennet discovered he does not understand consciousness is absurd: he surely believes he does understand consciousness (why would he otherwise write a book with the title 'Consciousness Explained'?). So how could he have discovered that that he cannot understand consciousness because he has no spiritual basis? It just makes no sense. The only conclusion can be that Dennett discovered that others, who lack a spiritual basis, cannot understand consciousness, they do not understand his explanation. But given that Dennet at least thinks he understands consciousness, it must be his discovery that others lack the spiritual basis needed to understand consciousness. Therefore, Dennett himself must have this spiritual basis, because he understands consciousness (according to himself). Others may think that Dennett does not understand consciousness, of course, and they may even say it is because Dennett has no spiritual basis. (Needless to say I do not agree.) But that is not Dennett's discovery. First I was not quoting at all, I followed an implication of what jonnobody said. And secondly, between all the arguments we had, I do not remember that you ever blamed me of misquoting you. My main problem with you was that you often used an argument along the lines of 'I researched consciousness many years, so my viewpoint is superior'.

I notice that the display can show min and max temperatures. Maybe you have to do a reset of these values. It could be the lowest temperature during its transport, or, when you yourself had to put the battery in, the lowest temperature it can measure. The flashing is a sign that the values cannot be trusted (think about good old video recorder clocks, flashing continuously with 12:00). So I suggest, read the manual, and find out how you can reset the min/max values.

My dissatisfaction lies in the thought that we still do not have all (meta)physical entities we need to understand consciousness. We do not need souls (that would be old-fashioned metaphysics), but also no new basic physical discoveries (no quantumgravity, as Penrose seems to think), nor: My intuition tells me that behind such ideas (all 3 examples) is a (rest of) a need to explain something that is quite mysterious like consciousness, with something that, well, at least feels as mysterious as consciousness itself. After Dennet presented his 'multiple drafts' theory of consciousness in Consciousness Explained, he discusses many variants of 'something is missing in this theory'. He goes into painstaking detail to show that nothing is missing (qualia, e.g.). In general, part of my life view is 'no metaphysical comfort'. Do not build the meaning of your life on how you think the world factually is. No God, no soul, no magical inner connectedness between all living and/or conscious organisms. A nice example here is George Lemaître: he advised the pope not to make the Big Bang as proof for God: for when science would discover some day that there was no Big Bang, or can explain the Big Bang physically, this 'God' would be gone. I hope these words will spiritually awake jonnobody, the OP.

Well, that is a difference: I think enough complexity to 'implement Joycean machines' is sufficient. No deep physics needed. I think I am more of a reductionist than you picture me... 😉. I think it is not such a bad analogy. Especially because on the level of individual particles pressure does not even exist. You do not look for 'deep physics' to explain pressure, do you? To explain pressure we must look at the collective behaviour of many particles, of which we know how they behave. In the case of our consciousness, I think we do not have to look deeper than the chemistry of the brain, and possibly even less deep: maybe only the formal ways neurons function really matter. If the latter is the case, then consciousness can possible exist based on other objects than neurons, as long as they formally work together as neurons.

The best philosophical joke I heard in a long time! I wholeheartedly disagree. Easiest reason for my disagreement is that we only see conscious behaviour in organisms that have sufficiently complex (neural) structures. So the only 'requirement' for physics is that it allows such complex structures to exist. So complex chemistry seems a sufficient condition for such structures. Yep, and therefore you do not need 'deep physics'. What you need in Dennett's view is a complex structure of anything that can implement what he calls a 'Joycean machine' (pity enough the only really existing 'Joycean machines' we know are implemented in neural structures). There is a 'darwinian struggle' between the many 'drafts' of intentions, observations, thoughts etc, and only those that leave a trace in my actions and/or memory are conscious. And that is surely not a simple linear, serial 'stream of consciousness'. Consequence of this idea that there is no exact place in the brain where consciousness happens, not even an exact time. In his Consciousness Explained Dennett presents many examples where the brain is fooled in the real timely order of events. So no, no command centre where all the sensory input comes in, and all the motorical output comes from. So Dennett uses a 'spiritual basis' to explain consciousness? Can you point me to articles/book passages that show he does so? If you think that this is an example of 'spirituality', it seems to me you have not even started to understand what spirituality is about. And when you equate 'Nirvana' with 'God' then you cannot be a precise thinker as well. Sorry for the long wait. Now you know what to think 🤪 Short note about free will: Dennett has a strong naturalist world view, and at the same time he is one of the biggest defenders of free will. But compatibilist free will of course, not one that needs some 'spiritual mumbo-jumbo'.

I have a question about the mRNA vaccines. As far as I understand, one of the advantages of the mRNA vaccines is that the RNA can be synthesised pretty easily. So what is the problem to change the RNA, so that it produces better immunisation against the newer COVID strains? E.g. base it on the RNA that is responsible for the spike protein of the Delta variant. Is this organisational (new RNA, so new vaccine, so new process of approval), or are there more technical problems? And another question: why base the mRNA vaccine on the spike protein? The only requirement for a vaccine is that the virus cannot multiply in the human body, not that no single body cell can be infected by the virus. Wouldn't there be parts of the virus that have a slower tendency to mutate? The immediate possible advantage of mutations that effect the spike protein might stand under heavier evolutionary pressure as other mutations, e.g. of the envelope of the virus.

I think Joigus made an excellent job here. Not giving the absolute, technical correct explanation, but trying to pickup from the estimated level where the questioner stands. Joigus presented the Einstein Equation, which really has (kind of) the form he presents. On one side stands a mathematical description of the curvature of spacetime ("Geometry"), and on the other side the possible sources of that curvature ("Matter"). Maybe one could say that "Geometry = Gravity" is a postulate of general relativity, but is definitely not the Einstein Equation itself.

You must distinguish between the many different contributions E made to physics. But I assume you mean relativity: special- and general relativity. For special relativity, the time was ripe for its discovery. Several physicists before (Fitzgerald, Lorentz, Poincaré, and several others) already guessed the correct formulas. It was even Poincaré that called the Lorentz transformations that way. But Fitzgerald and Lorentz used more or less ad hoc assumptions to derive them, e.g to explain the null result of the Michelson-Morley experiment. Poincaré's views already circled around the concept of 'relativity', but could not overcome the idea that there is no absolute frame of reference (i.e. a frame that is in absolute rest). E had some help of friends, but their role was more or less that of a 'resonance board'. Explaining his views and problems, E came at the solution himself. It is different in general relativity. E saw an inconsistency between his own theory of special relativity and Newton's law of gravity. He discovered after a few years that he needed descriptions of curved spaces, and asked his old friend Marcel Grossman how curved spaces could be described mathematically, and it was he who introduced E to differential geometry, of which E found that it was 'notoriously difficult'. in 1915, E got stuck, and visited David Hilbert, a specialist in differential geometry. After their discussion E found the solution in a few weeks, at more or less the same time as Hilbert found it too. But Hilbert later said, humorously, 'Every street boy in Göttingen knows more about differential geometry than Einstein: but Einstein had the physical intuitions that led him to the right formulation of the problem'. There are articles in Wikipedia about the development of the 2 RTs: - https://en.wikipedia.org/wiki/History_of_special_relativity - https://en.wikipedia.org/wiki/History_of_general_relativity

No, no, this is not the way it works. Say you are mining real, physical gold. That also costs a lot of energy (and labour). If you can't earn those costs back with the gold you are selling on the market, you would consider to close the mine. With Bitcoin it is the same: your mining costs energy, infrastructure (especially powerful computers). But then, if you have created a new Bitcoin, you go to the market with it. If your costs were $15'000, and the Bitcoin is worth $20'000 at the moment you have earned $5'000. But if the Bitcoin is $10'000, you have to accept a loss. And you might consider to 'close the mine', i.e. do not 'calculate' Bitcoins anymore. Or did you clear that point up already? I did not read every posting.

More or less. But I think I should wait for MPMin's reaction. You see, if you introduce too technical details, there is the risk of a 'conceptual overload'. Either MPMin understands what I mean, or (s)he asks more detailed questions him (her?) self. You see, sometimes my toes curve, not due to space curvature, but because I see that a curious beginner gets confronted with all kinds of technical details that he cannot see through. So this is a didactic principle of mine: try to connect as much as possible to the level of understanding that the questioner has. This risk is exactly shown here. You and Swansont get in a detailed discussion, that might just demotivate the questioner. I would always try to avoid that. And if the technical discussion is interesting enough, one could start a new thread. In the end, MPMin wanted to know if the (none)-infinity of the universe has something to with its (none-)flatness. I think I did sufficiently reacted on that question. Exactly.

No. 'Flat' means that e.g. parallel lines stay parallel, no matter how far you compare their distance between them. Best example is two light beams. When these do not converge or diverge, the universe is flat. It is difficult to imagine how a positive curved universe can be infinite because it is closed in itself, like the surface of a sphere. But with negative curvature and flat space that problem does not arise. Just take care that the universe seems to be flat on average. Locally, due to mass and energy, the flat universe can be curved.

Recently Ethan Siegel has an article about it: starts with a bang.

I am not a CC expert either, but I picked up, that also financial transactions cost a lot of energy. AFAIK this is because enough of the delocalised blockchains must confirm the transaction before it is definite. Googling I found this comparison: From here.

Yep. It is called gravitational redshift.

This makes no sense. We know 'Newton' is not valid for velocities that are comparable with light speed. So at one side you apply 'Newton' (E = 1/2mv^2), on the other side you apply relativity by saying that the speed of light is speed limit. You need to use relativity from the beginning, and then you will see that a proton accelerated to 7 TeV flies just a tiny fraction slower than c.

In addition to MigL comment on time dilation: at the event horizon of a black hole time dilation for an observer on a big distance goes to infinity. That means the frequency of an EM wave goes to zero, and the remote observer will not see any EM radiation.

See it this way: getting out of a gravitational field costs energy. Objects with mass lose kinetic energy, which means they slow down. Light also has energy, but it is not dependent on its speed, because it always has the same speed. But the energy of light is related to its frequency. So light 'loses frequency', which means its frequency goes down, i.e. it becomes redder. Now imagine a light beam with less energy than needed to get out of the gravity field. It would have no energy anymore, which for a wave simply means it does not exist anymore. At the event horizon EM radiation just has not enough energy to escape. Physically maybe not completely correct, but it might help to develop your 'physical intuition'... It is true, using daily intuitions it is impossible to understand modern physics. Throwing away physical theories because it does not fit your intuitions is the worst you can do. (In fact, it is one of the strongest motivations of so many 'crackpot theories' that are also posted on this forum).

Ethan Siegel in 'Start with a Bang': Why You Should Doubt ‘New Physics’ From The Latest Muon g-2 Results It throws doubt about the correctness of the theoretical calculation of the value of g-2. So there might not be a discrepancy between experiment and theory, because the calculation is not rock solid. But hey, how many articles appeared with new physics explaining neutrinos traveling faster than light? Hundreds? But it was an experimental error. This time I set my bets on a wrong calculation.