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Everything posted by Strange
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Unstable particles cannot decay when observed?
Strange replied to RandomBoy's topic in Quantum Theory
My (limited) understanding is not that it adds energy but that the act of measurement "resets" it. So it never progresses. -
One. If there were separate universe created by separate Big Bang "events" (if there is any such thing) then they would be completely isolated from one another. Let's say at the time the CMB was released. In that case, the scale factor was about 1100 so the distance would be about 9 billion light years. Who says it could? In fact, it couldn't. That is why it is outside our observable universe. So, this is the "horizon problem": how could the universe be in the same state everywhere unless it was small enough for light to travel across it. The most generally accepted answer is inflation. But there is no solid evidence for that and there are other possibilities (like, the universe took an infinite time to evolve to the state where it started expanding and so the whole universe was in the same state at that point). It will always be with us (but it will get cooler over time). The link I posted earlier explains how this works.
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Wave particle Duality inspired by a thread in Chemistry
Strange replied to studiot's topic in Quantum Theory
You might think you can tell nature what to do, but I suspect you will have less luck with the moderators here. This is you telling nature how it is allowed to behave. You have invented a "discontinuity in reality" and decided it is impossible. However, a photon will continue to do whatever it does (whether that is gradual or instantaneous). That equation describes the energy of a photon. Which can't be divided. A classical waves can obviously be divided. You can see it happen. It would be silly to say it can't happen. No just intuitive but obviously correct (assuming the source radiates omnidirectionally). PHOTON. You have just quoted the e=hf relation which defines the quantum for electromagnetic radiation. So you seem to both accept it and reject it. That's very, uhm ... quantum of you. In terms of evidence, the first was Planck's solution for the black body spectrum followed by Einstein's explanation of the photoelectric effect. https://en.wikipedia.org/wiki/Ultraviolet_catastrophe http://spiff.rit.edu/classes/phys314/lectures/photoe/photoe.html If you were to add energy to that gamma ray photon then it would become a higher energy (i.e. higher frequency) frequency photon. It would remain a photon. -
Newtonian gravity and GR will produce exactly the same results so it doesn't matter which you use. Although it is possible, as I say, that it could require a modification to our understanding of gravity, that is looking increasingly unlikely. But, of course, various people with a great deal of detailed knowledge and in-depth understanding are still looking at that possibility. (So are a few uneducated idiots, but that is hardly relevant.) Here is an article on some of the recent work on modified gravity to explain dark matter: What if dark matter is not a particle? The second wind of modified gravity.
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Unstable particles cannot decay when observed?
Strange replied to RandomBoy's topic in Quantum Theory
It only applies to certain types of changes, not all particle decay. And it is a result of making measurements. The measurements affect the state of the particle or system. Here is an analogy. Imagine someone walking along a road. Every so often an "observer" wants to know how far they have got so he asks the person to stop while gets a tape measure (or laser range under) out and measures how far they are from the starting point. If the observer does this once an hour or every ten minutes, then it won't have any effect on the walker's progress. But if it is done every second, then the walker will never get anywhere. (Maybe someone who understands the effect better will say if that is accurate or not!) -
This includes the results from VIRGO in Italy: https://www.forbes.com/sites/startswithabang/2017/09/27/ligo-virgo-detects-the-first-three-detector-gravitational-wave/#5e570c387f8f
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That is not exactly relevant, though, is it. And what is the source of this document?
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Holographic Universe Hijack (from Quantum Entanglement ?)
Strange replied to Itoero's topic in Speculations
Thank you. But note that it doesn't say that wave-particle duality is related to uncertainty. It is wave-particle duality relations that are equivalent to uncertainty; for example, the relationship between interference viability and path distinguishability. Although, I was not aware of this, it isn't too surprising. As you were talking about photons, I'm not sure how this is relevant. (Incidentally, you can describe the above using only rest mass by using the relativistic equation for acceleration.) Many professional physicists and educators disagree. But many also find it helpful. It is certainly not a "downgrade of knowledge" as it is just a different way of describing the same thing. Confusing is not the same as complicated. Only if you define "exact mass" as including relativistic mass, so this is a circular argument. -
Strictly speaking, this not to make relativity work but just make gravity work as expected. You don't need relativity to calculate the expected speeds, Newtonian gravity will do. I will look at the link later when I have more time.
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How do you define "perfect"? What if someone else has a different definition? At least one, if not two, of those don't fit my definition of "perfect".
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That is (or was) certainly one of the possibilities; that "dark matter" could be explained by modifying the way gravity works. There are a whole class of modified gravity theories. The most well-known is MOND (Modified Newtonian Dynamics) and there are various versions of this which attempt to match General Relativity (but still account for the effects of dark matter and/or dark energy). However, none of these have been very successful. The same modifications do not work for both rotation curves within galaxies and the orbits of galaxies within galaxy clusters. Also, they cannot explain the fact that we can see the distribution of dark matter around and between galaxies by means of gravitational lensing. Also, recent attempts to simulate the evolution of the universe and reproduce the large scale structures we see only work if dark matter is included. Then there is data from the CMB ("baryon acoustic oscillations") which also requires dark matter to be present. All of these work with the same amount of dark matter. So this seems a better solution than ad-hoc modifications to gravity. As far as I know, dark matter has no measurable effect on the movement of the planets (it is too diffuse) so I am not sure what you are thinking of here ...
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I don't think virtual particle pairs exist for long enough to be affected by the environment. (But I may be wrong.)
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There are so many things wrong with this ... Firstly, you can't reach the speed of light! Secondly, and more importantly, when you say that going from zero to c (*) is an acceleration of 299,792,458 m/s^2, that is only true if you achieve that speed over 1 second. What if you you reach that speed over 1/2 a second or 1/10000th of a second? The acceleration will be that much higher. Also, you can accelerate continuously with a constant force and you will never reach the speed of light. In your scenario you would need to apply ever increasing force to maintain the same acceleration in order to approach the speed of light. Finally, when talking about acceleration to relativistic speeds, you need to be clear about which frame reference you are referring to. So, for example, a rocket could leave Earth and accelerate at a constant rate (say 1g) in their own frame of reference. An observer on Earth would see them approach the speed of light after about a year and the rate of acceleration steadily declining. (*) Note: "c" not "C". The latter is carbon or degrees centigrade. Why not half a Planck time? Or 1/1000th of a Planck time?
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It is quite pleasant being able to point out where scherzando is wrong without having the face the insults he throws at everyone who disagrees with him.
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We Can't revert to html during edit of posts
Strange replied to scherado's topic in Suggestions, Comments and Support
Exactly. There are times I would have found it useful. But nothing insurmountable. But if this isn't supported by the forum software, there isn't much the mods can do about it, I guess. -
Well, praise is due for a sentence which is simple, clear, grammatically correct and factually correct. I might have given you an upvote, but for the fact it is also largely irrelevant.
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'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
I would have thought that the change from a concept of universal, absolute time to that of time being observer dependent was a not insignificant change. Also, there has never been a single definition or understanding of time. -
'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
Good. I also assume that your refusal to answer simple, direct questions is because you are a troll. -
'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
That really wasn't worth repeating. You didn't even attempt to fix the grammar. Ditto, the following posts. Repeating incoherent nonsense doesn't make it any less incoherent. -
'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
Oh my god, it's full of stars. (David Bowman) -
Doesn't this already? People write letters to newspapers, appear on TV, post on the Internet, hold demonstrations, organise petitions, meet with their representatives, lobby, pay bribes, etc. All of these, and more, allow people to influence the way the country is run.
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'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
For once, I do understand the question. Well done. Do I want to reconsider my question? No, why should I? You said "We can dispense with that conception of 'Time'" and I asked what the consequences of doing that would be. It seems a reasonable question. But feel free to ignore it. Now, if you had asked if I wanted to reconsider the following sentence then I would have been happy to withdraw the facetious comment, if it meant you might get to the point. I am now literally wetting myself with anticipation. Obviously you are not going to reveal the Great Secret now. But can you give us a hint. Will it be within the next 24 hours? Or will you just provide us with another cryptic hint? I will assume that you have put me on ignore and will no longer ask you any direct questions. But I reserve the right to continue making sarcastic comments about your increasingly incoherent and nonsensical posts. -
'Time': The Civilizational Edifice and Handmaiden of Matter
Strange replied to scherado's topic in Speculations
And here is me thinking this thread was about The Nature Of Time. Silly me. -
Well, for one thing dark energy has no measurable effect locally (it is only noticeable on large scales because the universe is so large). So its absence would make no difference. Also, the idea "push gravity" is very old and can't even explain Newtonian gravity, never mind GR. And what would be doing the pushing?
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We Can't revert to html during edit of posts
Strange replied to scherado's topic in Suggestions, Comments and Support
There is a preview button, although it is not obvious. It is the second from the far right (looks like a page with a magnifying glass).