Eise

Well, @Markus Hanke, it seems we have to wait for a cluster of quantum computers, each with 1 TB of QBits, before this is getting solved... Slowly I get to think that your idea about the problem of solving the n-body problem with GR might have a lot of truth in it.

Wow, so much misunderstanding. I made red, what you are missing completely. Not necessarily, here are my comments: gravitational lensing: is explained by GR Bullet cluster: that could be very well be DM. BTW, DM of the Bullet cluster is hypothesised on the basis of gravitational lensing. gravitational time dilation: is explained by GR gravitational waves: explained by GR It's no use to go on. Especially because I said several times that I think that DM is the best explanation, as said, with citations of my own postings, and you do not seem to even see that. Let's wait for for what astrophysicists will discover, OK?

Trying to find something is not the same as dogmatic stating that it exists. I would find it exciting if DM is found, and identified (axions? sterile neutrinos? WIMPS? something completely different?). And if Markus would be right, I could even say that the situation is similar to 'Vulcan or Neptune': the latter was the explanation of irregularities in the orbit of Uranus; the first explained the irregularities in the orbit of Mercury by the limited validity of Newtonian gravity. Yes, you created a crackpot theory (e.g. your 2018 thread). Just as an analogy: a few years ago it was 'discovered' that neutrinos could travel faster than light. And suddenly there appeared many articles (if I remember correctly about hundred articles on Arxiv) that tried to explain this phenomenon. In the end it was a bad connection of the timer. I never did. I only said that it is a possible explanation for rotation curves of galaxies, i.e. it is a hypothesis why rotation curves are what they are. But it does not explain what is derived from e.g. the CMB or the bullet cluster. Otherwise show me where I claimed MOND is the correct explanation for rotation curves. But I did! DM! So it is my favourite. But as I said already: And then there is @Markus Hanke's idea. Markus, are you aware of any physicists having similar ideas?

Who is 'some'? What are their arguments? I in any case I do not 'remember' it. Yep. As with Buddhist, Jewish and humanistic values, just to name a few. So clear projection from your side. Name these biographies. If you can't, this is just hot air. I already said this: it is metaphorical speech. Like 'The God particle', or 'Sneaking a Look at God's Cards' (a very good book for laypersons about quantum physics). Nope. Spinoza's concept of God is impersonal. I do not think so. He just gave Spinoza's concept of God as an example that is close to his. Nope: So no purpose in the universe. Sure. At least it works like that for me, even if my scientific stature is a bit lower than Einstein's. Wot??? Simple followers of an organised religion (or any other world view) I would not call 'spiritual'. See Exchemist's comment: Yep, as a metaphor. Just to note: both Einstein and Spinoza had deterministic world views. QM does not fit well into a deterministic world view. Yes, but also he abhorred fascism with its glorification of everything military. Several colleagues of him in Berlin succumbed to it, which must have been unbearable for him. And then there was also 'German physics' in which he was heavily attacked, because of his relativity theories.

No, they aren't. DM is a viable hypothesis, so they are completely correct to search for it. You are the one who takes it for granted because your pet theory about relativity is based on it. I think I will take your disappointment as a medal of honour.

Yep. Your continuous misunderstanding is tiresome. And the misunderstanding has its followup here: Where did I say scientists should stop? It is a critique on your position, that you already take DM for granted, and therefore close your mind for other explanations, or combinations of thereof. And this: Yep. Why? Because MOND is meant to explain galaxies' rotation curves, and possibly galaxy's movements in clusters. Just to say it again, I like a solution with DM as one solution for all, I wrote that already several times. DM in your ears would also explain why you after at least 2 repetitions of the same point, still do not get what I am saying: just don't fixate on DM as a solution for all phenomena that it should explain. Oops, missed this: Well, to be pedantic, I am right. Not in the idea that there are other (combinations of) solution(s), but simply the fact that the science is still open.

Gravitational lensing and gravitational time dilation are not "established science" (more accurate, real facts/observations, because a new theory must be in agreement with the facts, all of them, not necessarily with the previous/existing theories)? You really think that MOND may ignore gravitational lensing and time dilation? Yep. And you still do not understand me. I think I have to yell: It is not established that dark matter is the common cause of all phenomena that we attribute to it. Did you hear me now? I find @Markus Hanke's Ansatz very interesting. However, I am not sure if it could explain e.g. the separation of DM from normal matter. And also, do not forget that such observations are heavily theory-loaded, so I also cannot totally exclude the idea that these observations are wrong. Maybe look up a few youtube videos of Sabine Hossenfelder about dark matter.

Like what @joigus cited? Calaprice, Alice (2000). The Expanded Quotable Einstein. Princeton: Princeton University Press, p. 217. Einstein Archives 59-797. That is true. There are a lot of Christians who misuse Einstein's metaphorical use of the word 'God' to state that Einstein believed in a personal god. Joigus' citation should already make clear, that he did not. Really? Such as? Citations please! Why not call it a happy and fulfilled life? Please stop projecting your ideas on Einstein's life. Find historical sources for your ideas, as Joigus and I did, or just admit you are wrong. Did you even read Joigus' and my postings? Your reaction reads as if you did not read them at all. In the first place I already cited the letter you were referring to, and in the second place Joigus' citation shows that you are already wrong about Einstein believing in a personal god.

I don't think so. You are just too pre-occupied with DM to see what I mean. No, not necessarily. I agree that 'one solution for all' phenomena that hint at there being more mass than we can see is the most 'beautiful' solution. But that being said, science is always in for a surprise. As long as we have not observed DM directly, it still could be that there are different solutions for these different phenomena. Maybe MOND is the correct solution for the rotation curves, maybe we do not apply GR correctly on the universe as a whole, and so we interpret the CMB incorrectly, and the Bullet Cluster phenomenon has again another explanation. I don't know, and you neither. So it is a 'two-stage rocket': do all these phenomena have the same cause, namely DM? If so, what is DM? I am open to the idea that the answer of the first question is 'no'. You already take it for granted that the answer is 'yes', and therefore speculate (already) about what DM is. And looking back at this 2018 thread of yours, I assume that you are blind for my, in my opinion, methodologically correct approach, that even the first question is still not answered. Just be sure that when you speculate, you are correct about the established science. And I am not so sure if this meets that criterion:

How is MOND explaining gravitational time dilation? What did I say MOND is supposed to explain? To be sure, I also made the 'if' bold. Hope you now understand my sentence. I sense some aggressiveness in your questions and reactions, which make you blind for what people are really saying. If I remember my physics correctly, if the collisions are absolutely elastic, then yes. One particle may lose some kinetic energy to another one, but the other one gains it. Grrr... Partially cross posted with Mordred again... But yes, starting a posting, then eat an evening meal, and then continue the posting, might be not so a good idea.

On my Android tablet, I use the browser 'Via'. I've never seen a single advertisement there.

Only based on primary sources, not on some general speculations on 'no atheists in foxholes'. So here it is: Here the whole letter: So was Einstein religious? In a sense. The only thing in my opinion, is that the word 'spiritual' would better describe Einstein's position. At least most religions have some kind of 'divine metaphysics', to none of which Einstein subscribes. 'Spirituality' is not dependent on any kind of metaphysics. It is about finding a way to live as an individual in a much wider cosmos, be it divine or 'godless'. I wonder why you didn't lookup it yourself. Aren't you interested in improving the quality of the debate? Based on what? You are speculating again. Einstein, as a foreigner with German background, and known pacifist, had no access to any secret projects of the military. The movie is not totally historically adequate. It is good, however. But do not use the movie as historical reference. Speculating again. Sorry, your thread is totally ideological, and has nothing to do with the facts we know about Einstein. I think it should be moved to 'Speculations', because there you have to base your ideas on empirical facts.

Interesting Ansatz. 2 Points: Aren't the distances between stars and so that big, that Newtonian mechanics can be used? (Therefore MOND). Would it possibly explain all observations that hint at DM? For galactic rotation curves and movements of galaxies in cluster I can imagine it does. But CMB and separation between DM and baryonic matter in colliding galaxy clusters? Zwicky studied the movements of galaxies in galaxy clusters, and concluded that there was not enough visible matter to explain their movements. Just a tiny, historical detail. It was Jan Hendrik Oort: Zwicky was Swiss, Oort was Dutch, so as a Dutchman living in Switzerland, I take this very personal .

Can we stay on topic, please? I am interested in this device. And yes, it measures gammy radiation. I wonder if beta decays in a nucleus are usually followed by emission of gammy radiation. In the end, does the nucleus not 'reshuffle', because on its nucleons has changed?

https://letmegooglethat.com/?q=how+do+computers+work+for+dummies

The promise is a small device, which can be connected to a smart phone, and register, identify, display graphically (spectrum and in intensity in time; also on Google Street Maps or Open Street Maps), radioactive substances, better (and cheaper!) than traditional Geiger-Müller counters. Here is their website. Here is a report of a physicist playing around with it. Some excerpts: I always like to measure things around me: where am I and how high (GPS), what is the temperature, moisture of the air, water temperature of the lake near my house, and on and on. Maybe I am a bit nerdy...

Escaping death from Nazis Germany. Making ground breaking discoveries and enjoying life seems like a blessed life. But back to Einstein as a Christian could living in the U.S. introduce him to Christian values. He wrote many essays that were more than just philosophies where he looked to improve society and his adopted American life. So the ingredients are there. I’m saying old Einstein is a different man than young Einstein. He lived through WWII. He also wrote a lot about the Jewish people. Maybe he writing the stuff and doesn’t know it shares many Christian values. And maybe while he is in the hospital a chaplain gets him saved. Easier to understand than relativity. Why all this speculation? There are enough articles from Einstein himself and several of his (serious) biographers to find out yourself. So either do that, or take my word for it (below), but stop speculating. Einstein used 'God' either as a playful metaphor ("God doesn't play dice" (well, he calls it 'The Old One'), or as the impersonal, Spinozian God. The latter has nothing to do with the Judean-Christian God. He explicitly has said that he does not believe in some personal God, who interferes with the universe, or even stronger cares about peoples (Jewish or Christian) or even stronger, about individuals.

Yes, but that is not what is meant by 'WIMP': Bold by me. Wouldn't that mean that most galaxies also have a gas halo around them? Maybe they have, but I assume that such a gas halo would be extremely thin. In the end, most mass is concentrated in the galactic plane. Because the gas collided, got concentrated in the galactic plain so much that it could form stars. As explained by Mordred and me above. It doesn't. But my reaction was about rotation curves of galaxies. Ockham's Razor (slightly misused as Ockham originally meant it) suggests that having one single explanation for all phenomena that we connect to DM would be better. But maybe we need different explanations. Until we detect DM directly, and got enough knowledge about their properties, we simply have no proof. So if there are different explanations, then MOND, as explanation for rotation curves, is still a candidate. My opinion is that DM in some form, maybe WIMPs, maybe something else exists. But that is my opinion, the science is still open.

Discussing DM, and not knowing what rotation curves are? One of the strongest empirical hints that DM exists (except the alternative, MOND, turns out to correct).

Because, if DM really is composed of WIMPS, it does not interact with itself either. That means it does not contract to a galactic disk, because this is due to collisions of normal matter particles. For collisions you need some interaction. In the case of normal matter that would be EM mostly. X-posted with Mordred. Didn't realise he was still logged in.

Nope. Because: So you think that is more or less equivalent to studying astrophysics at a university? And to add to exchemist's points, there are more empirical points that hint at the existence of DM: movement of galaxies in galaxy clusters: they move faster then can be expected if we only take visible mass in account there is some evidence that when galaxies collide, DM and Normal Matter separate, due to the difference in how eager DM on one side, and NM on theother interact the CMB (Cosmic Microwave Background radiation) also hints at the existence of DM But as long as there is no direct observation of DM, it stays, as exchemist said, a placeholder for a set of phenomena we do not yet understand.

Neutrinos are not “the basic units of materialized energy” and there isn’t a pathway for neutrinos to form atoms. They don’t interact in ways that would allow that. You see, @graybear13, that is the problem. You do not even know what neutrinos are, so your proposal is dead from the beginning. So why do you throw so many absurd hypotheses into a science forum, suggesting that physicists would have a blind spot in their world view: 'Oh my, Why didn't I think of it!? Atoms could be made up by neutrinos! Good that people with fresh minds are also looking at this!'. Really? You think like that? If not, why you go on formulate hypotheses that every physicist knows will not work? Not even realising the difference between alpha particles and neutrinos, why do you even think you could bring up meaningful hypotheses based on them?

No, alpha particles are not neutrinos. They are so different that you cannot say 'Ah, neutrinos do not work for my idea? Then maybe alpha particles do?'. You are just throwing words around without knowing the concepts behind that words. For a mind that knows nothing, everything is possible in his fantasy.

What does 'contradiction' mean, according to you? Can one 'thing' ('truth' in this case) be a contradiction? Also, you only have to find one case where 'truth contradicts itself', and your question is answered.

Well, 'no change' is an empirically impossible situation. The best we can do is define 'standard changers', aka 'clocks'. Then we can compare durations of processes with the number of 'ticks' of our standard changer. If we agree on such a standard changer (like an atomic clock), and on the scale of the units we use (so many ticks are 1 second), we can define a kind of 'absolute time'. 'Absolute' in the sense that we know that 1 second for one observer, is also 1 second for another one, assuming the clocks do not move relative to each other. In special relativity, we notice that all clocks in a system that is moving relative to me slow down: the atomic clock, the quartz clock, grandpa's pendulum clock, etc. Then we can justified say, that time has slowed down in in the frame that is moving relative to me. 'Movement' is just another change that can occur, as you say, a change in spatial location. I would not necessarily call it a measure, for a measure of time a reliable extremely fast periodical change is the best way to attach a time scale to it, and so can become a measure.