Everything posted by joigus
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What can and should be done to address the world overpopulation crisis?
Yeah, hunter-gatherers are the problem. Sigh
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What's your worldview?
I shy away from worldviews (try to), even though sometimes I can't help getting tangled in them. There are too many obstacles, some of them really thick, to acquire any kind of a vantage point. And the individual perspective is only too limited. I see a piece of landscape from where I stand. That's all. Besides, there are already too many Manichaeans out there, preaching with too loud a voice. I don't want to be that person. I must side with Genady here, but as a dream perhaps. That some day mathematics, logic, and similar tools of analysis can tell us what this or that pattern does in the great scheme of things. As for the rest, such tools will hopefully tell us why and what in the world cannot be understood on account of logical/semantic incompleteness. Mathematics is so... dispassionate. Atheism is not a worldview, btw, as far as I can discern. It's more of a 'what do you mean by that' attitude the way I understand it.
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problem with the calculation of the wavelenght.
Also, \( \nu \) in \( E = h\nu \) is the Greek letter nu, while \( v \) in DeBroglie's relation \( \lambda=h/mv \) is the Latin letter v. Could that be related to your problem? IOW, one is the frequency in Hertzs, while the other is the speed.
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Is depression caused by low serotonin?
I'm no expert here, but feedback mechanisms in biology are so frequent that I think pointing to the presence/absence of a certain chemical as the cause of an illness (or of any other process for that matter) is probably not the way to go.
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Your favorite science popularizer?
It's Sagan, of course. And after that, Sagan. The poetry, the music, the absolutely unfettered passion for understanding it all that cannot be muffled in any way. The Cosmos is all that is, or was, or ever will be... And I was immediately and unconditionally engaged for the rest of my life. As to the rest of them, I can't help but feel they've been built as marketing products in a way, probably through no fault of their own. I agree with exchemist that Hossenfelder means business more than any of the others. Sorry for the mixed metaphor.
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Helicopter Carrying President of Iran Lost - Accident or Assassination ?
Agreed. A couple of disgruntled shepherds throwings stones could have startled the pilot just enough to do it. And discontent there is in Iran, as pointed out. But no need for a plot here, and most likely an accident. That doesn't mean the Israelies haven't uncorked a bottle or two. Agreed. I'm sure the next in line is not going to make much of a difference, turban-wearing or not. I'm pessimistic about your last wish though, however much I agree. Any hose-pipes I envision are political. And most problems in the Middle East are cultural and deeply rooted in people's minds, not political.
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Big Bang starting reference point
What @MigL is referring to is Planck's scale. If you want to probe space-time at scales roughly 10-43 seconds (10-35 m is another way to characterise it), you make black holes. So it doesn't quite make sense to discriminate between points, mesure distances, angles, speeds. There would be no geometry proper. And I agree also with @Genady that the big bang is not a point, of course. A picture that I find particularly attractive is that of conformal symmetry, which is a universe in which there is scale invariance. In a conformally-invariant universe, there's no difference between big and small in a way. AAMOF, we know when temperatures are very high, conformal symmetry is more and more accurate. The universe would look very much like Maxwell's equations with no sources. Perhaps scale invariance is a spontaneously broken symmetry?
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Octopus intelligence
@TheVat, @CharonY. Aaah. My friend has just answered. It was Peter Godfrey-Smith. A philosopher of science rather. And he is Australian. Sorry I must have thrown you off.
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Octopus intelligence
It could have been E. O. Wilson... I know his topic of expertise was ants. I don't remember him as making a big deal out of cephalopods. They're all Greeks to me now LOL. I'm getting old. I've just whatsapped my friend. See if he can remind me and it rings a bell to any of you.
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The simplest cause of the accelerating expansion of the universe
We know observationally, actually. The surface of last scattering has still not disappeared behind the kinematic horizon. The fact that there are features not totally explained by the standard cosmological model doesn't mean that we must throw everything away. All of them photons. All of them subject to extreme redshift when close to c as receding velocity. So your point is moot.
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Octopus intelligence
Very interesting points. I don't seem to remember (or successfully google up) the name of a very influencial biologist (American/Australian/British...?) who called for more attention to cephalopods, and proposed to study them as models of radically different body plans that could be the basis of intelligent multicellular life other than mammalian. I'm sure you know who I'm talking about... Very interesting topic btw.
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The simplest cause of the accelerating expansion of the universe
There are at least two reasons why this isn't true. One of them is that long enough ago (which is automatically implied by "far enough away" as you should understand if you want to do cosmology and astrophysics) the universe was opaque to radiation. A little farther beyond it was opaque to neutrinos even. And also there's a kinematic horizon, as Swansont explained. Photons from so long ago and so far away get redshifted into total invisibility. 🤣
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Gluon/Higgs
There are gauge bosons (particles mediating the interactions) that acquire mass via the Higgs mechanism though. The W and Z bosons of the weak interaction are the famous example, because they were the first particles for which the Higgs-Kibble-Anderson-etc mechanism was proposed. Back in the '60s it was known they shouldn't be fundamentally massive on account of a very important symmetry --called the gauge symmetry-- being broken if they were. They must be acquiring mass from something that's dragging them. Another field. Thereby the Higgs. People knew they must be massive in practice, as the weak interaction is short-ranged. So it's kind of peculiar that some of these mediating particles (gluons and photons) don't acquire mass via the Higgs mechanism, while others (Ws and Zs) do. At least I find it so. I think that's a very good question, btw.
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The simplest cause of the accelerating expansion of the universe
Not really. A gravitational orbit plus a dissipative environment will be a possible model to account for closing spiral orbits, as @exchemist has pointed out. It just doesn't seem to do what you claim it does. I would relax about getting credit for this idea for the time being.
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The simplest cause of the accelerating expansion of the universe
The acceleration of a rotating body is towards the centre of attraction. It's called centripetal acceleration. Tangential acceleration would require a completely different force field. Have you seen @Ghideon's picture? Do you know why he drew the acceleration the way he did?
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The simplest cause of the accelerating expansion of the universe
Very far from what? There are galaxies in every direction. It cannot be very far from everything. However far is "very far". Yeah. r is the distance, and m is the mass, and q is the charge, and I is yours truly. Distance between what and what? Again, there are galaxies in every direction. And galactic halos in every direction. How does that reproduce the velocity curves? You are mixing and mis-matching the expansion of the universe with the v(r) law for galaxies from the centre outwards. Very different things. One goes by the name of dark energy. The other, dark matter. Different names for very good reasons. The galaxy rotation curves are rotations of stars around the respective galactic centres. Expansion of the universe is about galaxies getting away from each other. You're not making any sense. At least about the universe we observe.
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Your thoughts on Neil deGrasse Tyson
He doesn't. They don't. I'm very partial to Sagan though, on account of the child in me, who got fascinated by science thanks to Sagan among others. If children today get to love science because of Tyson, he would prove to be a worthy disciple of his mentor. Do we need more? Neither one of them managed to shatter the earth in scientific terms. So I agree with @dimreepr: Does it matter? Do you have an opinion on it? I think you mean someone like Carl inspired someone like Neil. Don't you?
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Testing for Tolerance
I'm sorry to say you did. Here it is: (my emphasis) Reciprocal? What does that mean? I would have guessed "inversely proportional", but no. You at least displayed the maths, so there's no doubt what you meant. So yes, you did claim that, as then I asked, quoting you, so there could be no ambiguity about what I meant. Then you said, And now you change your statement. Other members have problems with the way you use units, justify your concept of "chronovibration", and ignore quantum mechanics, so taken as a whole, I'd say I have very well-founded misgivings that your theory could ever be turned into a sound one, considering you only claim to explain the anomalous quantum Hall effect. You've proven to me you have no understanding of what magnetic charge means in the context of the classical electromagnetic theory.
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Testing for Tolerance
I'm afraid that wouldn't work in keeping with what we know about electromagnetism. If the ratio of magnetic to electric charge is the same in all particles in the universe, you can then rotate every (electric, magnetic) pair to a new definition, \[ \left(\textrm{new electric quantity}\right)=\cos\alpha\left(\textrm{electric quantity}\right)-\sin\alpha\left(\textrm{magnetic quantity}\right) \] \[ \left(\textrm{new magnetic quantity}\right)=\sin\alpha\left(\textrm{electric quantity}\right)+\cos\alpha\left(\textrm{magnetic quantity}\right) \] And the new magnetic charge can be defined to be zero, with all the physics being the same. The Lorentz force law that @Mordred mentioned would have to be re-defined to be, \[ \boldsymbol{F}=q_{e}\left(\boldsymbol{E}+\boldsymbol{v}\times\boldsymbol{B}\right)+q_{m}\left(\boldsymbol{B}+\boldsymbol{v}\times\boldsymbol{E}\right) \] These are called duality transformations for the electromagnetic field. Unfortunately, neither the Wikipedia article, nor the Scholarpedia one, do a very good job of explaining what it is. If you're interested, I can do more, or suggest more material as an exercise. It's not hard.
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Your thoughts on Neil deGrasse Tyson
Ok. Thank you. I couldn't believe your statement. 😅
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Your thoughts on Neil deGrasse Tyson
I think you missed an "m"...
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Your thoughts on Neil deGrasse Tyson
I see. I don't think much that is essential has changed since the time it was written though. Ok. In that case the Amazon description could be misleading. It's only concenced with the postulates, and their logical consequences. IOW, whether or not the postulational basis of QM can be seen to describe the picture of a mathematical reality. Whether the logical implications correspond to empirical truths is taken for granted --it does-- and not a main point --or even a relevant point, AFAICR-- of the book. I see.
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Your thoughts on Neil deGrasse Tyson
@Eise is the local expert, if I'm allowed to say so. Eg, I'd heard about this David Z. Albert that he mentioned, but I'm not familiar with his work. The only book I can recommend is Michael Redhead's wonderful, Incompleteness, Nonlocality, and Realism, which I liked quite a bit. Carl Popper and Russell etc, are of course classics, but I assume you've got that covered. Bohm was very philosophy-inclined, but his philosophy is sometimes perceived as impregnated with mysticism. Really --and Eise's and others' recommendations pending--, Michael Redhead's book is a very good and very serious read. I assume you meant physics, of course.
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Your thoughts on Neil deGrasse Tyson
Maybe it's just an impression on my part, but I think many scientists are unaware of changes in philosophy having taken place in past decades, plus the relatively recent coming of age of a new breed of philosopher scientists.
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Testing for Tolerance
Does that same ratio hold for every charged particle in the universe? According to your theory, that is. I'll be working on other members' queries, btw. And I'm just curious. How did we come out in your tolerance test?