Active Users:183 Time:19/05/2024 07:46:01 AM
Re: I think most people would disagree Isaac Send a noteboard - 14/08/2013 06:11:34 PM

View original post
View original postThere's a huge amount of stories of every sort in science, as in everything else, which are bullshit or probably bullshit. Like I said, lots of people say there was a consensus science was complete, but always ones who didn't think so themselves, I've never seen (though I'm sure there are some) any writings form respected scientists of that era saying "Yep, science is wrapped up or nearly so"


View original postFair point; lots of people probably see themselves as Galileo or Einstein upsetting applecarts, and the temptation is arguably greatest within their field.


View original post
View original post
View original postThat was my point: Paradoxes tend to be hazy and troublesome, but their resolutions are often (and understandably) revolutionary. It seems save to say that resolving the contradictions between General Relativity and Quantum Mechanics will be no less earthshattering than resolving the contradictions between the theory of light-as-wave and light-as-particle. Hopefuly we can come up with something a bit more precise and satisfying than "both."


View original postI actually doubt it will be that earthshaking, it would be nice if it was but Olber's Paradox, as mentioned, was not very earthshattering in its resolution. I can name a couple dozen other big ones that were resolved as near footnotes. Duality itself, "It's both", doesn't really bug me anyway, it just is, same as opposite particles repelling, and anti-particle annihilating, we know how, why is probably not something we'll get to find out in the foreseeable future.


View original postThat is not much as resolutions go; we pretty much knew how particles and waves behaved before anyone determined "light has properties of both because that is what it is." It is an underwhelming scientific breakthrough, much like knowing the formula for universal gravitation (or, more topically, a black holes temperature) without knowing what the symbols mean. It STILL does not make much sense for anything particle-like to have wave-like motion even with no medium through which to propagate one, unless the wave-like properties are just a product of relativistic distortion near c (in which case, why no mass?)


View original postThat aside, your history of Olbers Paradox indicates it was rather obscure for most of its existence, which is relevant to its endurance. Recall my frequent observation few big controversies would exist if admitting easy answers; they also would not be big if few people cared or even knew about them. When most of the smartest people hotly debate a question they cannot answer with even the most advanced experimental equipment, it is likely that answer is beyond the smartest people, most advanced equipment or both. Such answers tend to be big unless defying all practical application, because they mean the human race did something previously impossible for it. The longer a question defies answer by the best minds and equipment, the bigger its answer is likely to be if/when finally discovered.

It wasn't 'obscure', not at all, more like "Where did all the matter from the Big Bang come from?", everyone knew of it but it wasn't something you could write up a formal scientific paper on because it is frowned on to say "I have no fucking clue" at the end of a long treatise. It wasn't publish or perish at the time, it was don't publish unless you had something pretty solid. The concept is routinely referred to back then though and in a very everybody-knows kind of way.


View original postObviously that will not ALWAYS be the case, but the circumstances of longstanding, widely and well studied, conundrums are conducive to it. By way of analogy, the Moon was neither paradox nor discovery, but if getting there were simple the worlds wealthiest and most advanced nations would not have spent a decade and billions of dollars trying, and the necessary advances had a host of radical lasting impacts wholly unrelated to space travel. There were plenty of breakthroughs most people rarely remember (if even aware of them) because the landing itself so overshadows them.

The moon has had a fair share of paradoxes around it as has both Jupiter and Saturn's. Look up "1003 Second Delay" or "Abberation of Light" sometime for Jupiter and there's all sorts of horrible conundrums involving Saturn's rings and our own moon. Not all are resolved yet either, for instance while we now know those rings aren't literal thin discs obviously proving God's existence we've got a lot of issues involving their composition and brightness that contradict various age estimates in favor of others that haven't been resolved, including the one band that rotates backwards.


View original post
View original post
View original postYeah, I saw that; that is, um, a lot of Greek. I am enough of a layman that saying something is "is Rindler in terms of tau=t/4M and rho=2u" tells me very little. I can see how we end up with an equation where T is equal to a formula with M in the denominator, but that does not explain the mechanics in operation. It only relates to temperature (i.e. elctromagnetic radiation) though, so the same relationship would not necessarily follow for some kind of stimulated graviton emission, which one would expect to be proportional to mass to at least some degree. It was just a spur of the moment notion though, spitballing; I am certainly not married to it, but am curious about the nuts and bolts (even if I may not have the math to follow them.)


View original postUnfortunately there are a lot of things in physics that require a lot of math to understand. I try to explain without it when I can, I'll even fudge reality a bit to fit a decent analogy, but there's not an obvious one to me for this that wouldn't be 'too wrong' to offer. From a practical standpoint just assume larger black holes are cooler because they have considerably more volume increase then mass increases, and emit less light because of that, same as a blackbody. Fill two objects, one twice the size of the other, with a cup of boiling water and dump them into the void and the bigger one will give off less background radiation. Same basic concept but the math is different, for instance you've got redshift of light as a huge factor for something outside a black hole's event horizon but still very under its gravitational influence.


View original postOkay, I follow that; thanks. I try to accept my limitations at least until/unless they can be overcome.

Learn calculus and they'll make more sense


View original post
View original postSince the SM doesn't include Dark Matter particles at all I'm not exactly worrying about the gravitons absence making the model not 100% complete and proven.


View original postFair enough, though I am leery of equating "unknown" or "undetected" with "exotic," mainly because the Particle Zoos spawned "new particles" almost monthly in the early days before people began to realize many of were just composites and particular interactions of existing particles. SOME Dark Matter consists solely of particles already present in the Standard Model, even if current indications are most does not. Without dredging up our MACHO discussion a while back, "strange matter," despite the misleading name, is still just quarks. It is one thing to say, "observations do not match theoretical predictions, so we are missing something," but quite another to say, "this model requires that 'something' be this particle with these properties." That sounds more like an excuse than a reason.

We've found quite a few particles by predicting something of about X mass needed to exist then hunting for one by creating collisions of that energy range. There's nothing wrong with predicting that way, so long as you label it a theoretical particle until you find one.


View original post
View original post
View original postEssentially that even Brownian motion would not hold intervening particles at or even near kinetic equilibrium, because our hypothetical onions volume dictates "rimward" energy sources will always greatly outnumber "coreward" ones. Therefore the intervening matter could and would absorb the difference and move about, rather than being locked in place and reemitting it toward the core. It will still radiate the difference "minus whatever small amount is going into momentum," but that "small amount" ought to be relatively LARGE for low densities (like, say, the interstellar medium.) The low mass and surface area does not allow much energy absortion per unit volume in the first place, and the low mass and negligible drag means it does not take much of it to get them moving, and every erg going to motion is not re-emitted. There is no core radiation bombardment because the exces all goes to motion, if only motion of very rarefied matter.


View original postI'm sorry I'm still not clear what you're trying to say here, as I said any system is almost bound to have a gradient (net direction of force that is non-zero after almost everything cancels out), it doesn't matter for our purposes, it's minimal, and in an infinite universe it just average out anyway but even if it didn't, remember that a particle flying away form us redshifts and gets dimmer, and toward us blue shifts and gets brighter, kinetic energy still contributes to an objects brightness.


View original postNot always positively though, at least not in terms of absolute energy. Red-shifting must lower the amount of energy we receive from an object, because raising wavelengths lowers frequencies and thus energy (I had never thought about it that way, but E=hf means it must be so.) So the brightness might not change, but it could well dip below visible lights threshold, and the energy level could fall until erasing all risk of cooking the universes center (if it had one.)

"Absolute Energy" is an iffy concept. An object moving fast relative to you has to be treated as having gravity equal to that extra mass energy. Temperature is also subject to relativity. Brightness, a somewhat vague term, does change, as a billion red photons are not as bright as a billion blue ones but much brighter then a billion infrared ones. An object emits X number of photons as blackbody, that's set, linear to surface area and to the cube of temperature. That's number of photons, power output goes as the 4th power of temp because the frequency/energy of photons goes linear to the temp. Those individual photons exist, their number is not relative. The energy of them is, so a hot blackbody racing past us, much like a vehicle siren sounding higher pitched till it passes us then lower pitched, can change. If I take a big mile wide orb and heat it up to 5000 kelvin and shoot it from a rail gun at Jupiter aimed to fly past Earth missing it by a thousand miles it will appear Green when it launches, but blue once it reaches its peak speed, until it flies past us and turns red. During that time that it is very close to Earth so that the light hitting us is moving at a steep angle relative to it's direction of motion it will dip to bluish green then green then yellow, orange, and finally red. Never did the number of photons change, but the energy of them, to us, did. Now our eyes are way too logarithmic, not too mention differently sensitive to red, blue, and green specifically, to notice, especially with the object having inverse-square alteration to its brightness from getting closer then further away, but the object will be dimming as it approaches and shifts redder as it no longer is as relativistic to us, even as it grows brighter form being closer.


View original post
View original postIf you're asking if a net outward motion would decrease the brightness then yeah, and if it were sufficient enough we'd have a dark sky... that's the point, everything has a major outward motion from us, expanding Universe, no paradox.


View original postThat was pretty much where I was going, yeah, even if I tried multiple routes to the destination. A photon or anything else striking a very low mass, surface area and density object should transfer a significant portion of its energy into new motion. Such particles can not absorb or emit much energy in the first place, have very little stationary inertia to overcome and there is little nearby to slow them once moving. If a mountain struck a pebble (only) even at very low speed the pebble would take off like a rocket because, hey, what else could it do? Per the Adams reference, our infinitely large onion could have an infinite number of very small (or even very large) particles between its inner and outer layers and the limit of its density would STILL be 0.

Joel, momentum transfer doesn't work that way, objects do not transfer disproportionate momentum. The pebble hit by a mountain moving 100 miles an hour is the same as a stationary mountain being hit by a pebble moving 100 miles an hour, it can absorb a maximum of twice it's momentum on impact, allowing it, if perfectly elastic, to leave in the opposite direction with the same speed.


View original post
View original post
View original postRight, the kinetic energy is practically (if not technically) nil, because so diffuse nothing can be done with it. Sorry, I sloppily said, "potential energy," instead of "matter," but of course the potential energy of matter at that point will be ACTUALLY rather than PRACTICALLY zero (that is kind of the point.)


View original postIn a heat-dead universe all energy is kinetic, its just all random with no pockets of greater or lesser to work with. That's entropy.


View original postAbsent potential energy kinetic is the only kind left, yes? And still practically useless for the reason you state. It cannot be random AND uniform, by definition though: If random it is uneven; if non-random, even. Then again, that really depends on space, which depends on gravity, which may not even operate at heat death. I guess the issue is what we specify by "disorder." I take your larger point though, and do not dispute it.

Something can be uniformly random, that's how gases in a room function. Two rooms, touching each other, each 200 and 300 kelvin respectively, can not have work done inside them, they are uniformly random, if I open the gate between them though I can accomplish work during the heat flow as they attempt to become a single uniformly random object at 250 k. If I'm using that work to turn a flywheel then they will equalize lower, maybe 240 K, slowly rising to 250 k as the flywheel encounters drag and friction and slows down, producing heat in the process.


View original post
View original post
View original postI never said it was insoluble, only that the solution is apt to be revolutionary, the more so the longer it eludes us, since we can only find it by continually increasing our understanding. Our understandings expansion is only possible in its paradoxes and frontiers. Maybe that is why we can never answer all questions: We could no longer ask them if we did.


View original postVery Zen. Also kinda meaningless, which is typical of such I suppose. Like I said, I don't know if there are a finite number of questions or if they are all solvable, I've never seen any evidence indicating that was or wasn't so, I know the questions we currently have and I'd like them answered if they can be, some may spawn more questions, some may not, I worry about those if and when they appear because otherwise it amounts, IMO, to a sort of fatalism.


View original post"Zen" and "meaningless" go hand in hand, yes, hence the koans. Finite or not I am unsure we were ever meant to answer every question, else it would tend to fatalist apathy, intellectual Alexanders not so much weeping as shrugging that we had no more worlds to conquer (not that that old legend holds more truth than most.)

Yes, but the nice thing about answering "How does momentum transfer work?" as opposed to "If a tree falls in the woods..." is that the former lets you build engines to move things and make electricity.

The intuitive mind is a sacred gift and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift.
- Albert Einstein

King of Cairhien 20-7-2
Chancellor of the Landsraad, Archduke of Is'Mod
Reply to message
Bored and irritated rumination on Olber's Paradox - 28/07/2013 03:21:37 AM 705 Views
I initially read that as "urinated." - 28/07/2013 04:17:47 AM 435 Views
It's tied to the Copernican Principle - 28/07/2013 05:09:58 AM 500 Views
That makes sense. Thanks, Issac! *NM* - 28/07/2013 03:54:54 PM 211 Views
Expansion's a bitch, innit? *NM* - 28/07/2013 04:37:26 AM 228 Views
I'm not saying it's aliens ... - 28/07/2013 06:03:25 AM 509 Views
Re: I'm not saying it's aliens ... - 28/07/2013 10:27:54 PM 1000 Views
Well - 28/07/2013 04:49:06 PM 567 Views
Re: Well - 28/07/2013 10:28:22 PM 598 Views
I always wonder about the magic solution to fix the math - 29/07/2013 01:30:23 PM 405 Views
Sure, that's basically what Dark Energy is - 29/07/2013 07:30:00 PM 449 Views
I, in turn, always wondered how black holes would permit gravitons to function. - 11/08/2013 09:37:39 PM 516 Views
They don't, yet they obviously do, that's the whole problem - 11/08/2013 11:08:35 PM 526 Views
Probably the first and last time "man on the moon" was put on par with "plentiful free online porn." - 12/08/2013 02:09:36 AM 490 Views
The latter is admittedly a far greater accomplishment - 12/08/2013 05:06:17 AM 623 Views
Meh, porn predates civilization; its novelty has faded. - 13/08/2013 06:36:13 AM 457 Views
I think most people would disagree - 13/08/2013 07:09:38 AM 1992 Views
Re: I think most people would disagree - 14/08/2013 09:05:32 AM 551 Views
Re: I think most people would disagree - 14/08/2013 06:11:34 PM 559 Views
Re: I think most people would disagree - 16/08/2013 07:37:46 AM 641 Views
Interesting Read - 30/07/2013 02:24:31 AM 391 Views
Re: Interesting Read - 30/07/2013 04:19:34 AM 402 Views
Fair enough - 30/07/2013 12:15:15 PM 435 Views
What if the universe is more like a sea urchin? - 30/07/2013 04:04:56 PM 459 Views
Re: What if the universe is more like a sea urchin? - 30/07/2013 11:04:49 PM 449 Views

Reply to Message