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# Story Friday August 30, 2019

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18 hours ago, hkmaly said:

Yeah. Now, how big is Los Angeles?

Not sure where you got those numbers. Wikipedie claims 52kg for Uranium-235, 10kg for Plutonium-239 ... and 2.73kg for Californium-252. Now again, why exactly should Skynet use plutonium and not something more effective?

(And I suspect there will be isotopes with even smaller critical mass if you don't care about shorter half-life.)

Los Angeles is big enough that you would need a multi-megaton explosion to have reasonable certainty of killing even the softest of targets located at a random unknown location within it with a single detonation. Therefore, you either need to locate the target more precisely and move the bomb into relatively close proximity (hundreds of meters or less), or you need something more potent than nuclear reactions if you want to conceal it within a frame the size of a T-800 (e.g. antimatter or some sort of zero-point energy).

I may have confused 52 kilograms with 52 pounds on the U-235 figure. As for Californium-252, its base radioactivity is 2.3 terabecquerels per gram, or about 62 Curies per gram (i.e. each gram will experience 2.3 trillion spontaneous decays per second, so about 6.2-6.3 quadrillion per second in a 2.73 kg mass). This is enough to cause predetonation and thus fizzile when attempting to use it to trigger a nuclear explosion. Basically, its radioactivity is so high that it will vaporize itself before most of the isotope can partake in the chain reaction.

15 hours ago, Darth Fluffy said:

"Chestnuts roasting on an open fire, Jack frost nipping at your nose ..."

And so I'm offering this simple phrase, to kids from one to ninety-two quadrillion . . .

Although it's been said many times, many ways

Merry Christmas to you!

3 hours ago, ChronosCat said:

The gap/inconsistency between General Relativity and Quantum Mechanics is the biggest unknown (or at least the biggest known unknown) in all of science; hidden within it could be the secrets of faster than light travel, time travel, all sorts of technologies out of the softest of science fiction, and stuff we can't even imagine. On the other hand, it might turn out that a unified theory's only practical applications are a few technologies which are useful but hardly the stuff of galactic empires (like how the effects of Relativistic Time Dilation need to be taken into account for GPS to work). I'm enough of a pessimist that I find a result closer to the latter more likely (but I would be thrilled to be proved wrong).

What we really need for FTL as we understand it is some means to generate the gravity-like warping of spacetime independently of hauling around large/dense chunks of matter. Essentially, we need a way of altering the ratio between gravity and inertia. In short, we need some way of generating a real-life Mass Effect. We're probably not going to run into practical natural deposits of something analogous to Element Zero, though.

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31 minutes ago, ijuin said:

What we really need for FTL as we understand it is some means to generate the gravity-like warping of spacetime independently of hauling around large/dense chunks of matter. Essentially, we need a way of altering the ratio between gravity and inertia. In short, we need some way of generating a real-life Mass Effect. We're probably not going to run into practical natural deposits of something analogous to Element Zero, though.

Natural? Probably not. Doesn't mean we won't have whole industry for producing exotic matter. Or might find some left after some other civilization.

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14 hours ago, hkmaly said:

I would say that the identity of Dark matter might be worse. Unless they are part of the SAME unknown ...

Wormholes are already something at least theoretically possible according to General Relativity, AND allowing both FTL and time travel, at least in limited way. Only thing missing is how to build one.

I almost said the Relativity/Quantum inconsistency was one of the biggest unknowns in science, though I do think it is the biggest. In addition to Dark Matter, other runners up are Dark Energy and whether we are a part of a multiverse. However there's a good chance the answers to those last two are tied up in the General Relativity/Quantum Mechanics question, and a possibility Dark Matter is too.

A Theory of Everything might allow for other methods of FTL and Time Travel besides Wormholes; it would almost certainly have something to say about whether wormholes exist and whether it's possible to create a long-lasting and traversable wormhole.

14 hours ago, Don Edwards said:

Are you saying that if relativistic time dilation didn't happen we couldn't make a working GPS system?

(The one we have, as is, wouldn't work... but we wouldn't have built a system that takes relativistic time dilation into account if we didn't know about relativistic time dilation, and if it didn't happen we wouldn't know about it. Or would already have tested for it and said Nope!)

I'm saying that if we didn't know about relativistic time dilation (but it did exist), GPS wouldn't work properly until the people developing it figured out how to compensate.

Granted this isn't a great example of technology made possible by knowing advanced physics (as we probably could have brute-forced it without knowing the underlying theory), it was just the first thing to come to mind. A better example might be quantum computers, but they haven't come into their own yet so it's hard to say just how much of a game changer they'll be.

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5 hours ago, ChronosCat said:

I almost said the Relativity/Quantum inconsistency was one of the biggest unknowns in science, though I do think it is the biggest. In addition to Dark Matter, other runners up are Dark Energy and whether we are a part of a multiverse. However there's a good chance the answers to those last two are tied up in the General Relativity/Quantum Mechanics question, and a possibility Dark Matter is too.

Ok, I should've said "Dark Matter and Dark Energy", because I assume it's same unknown.

Whether we are a part of multiverse is theological question. The physical question you have on mind is if there is way to transfer information, energy and/or matter between our universe and some other universe in the multiverse.

(To be more exact: even if there IS such way, we can only confirm existence of finite amount of other universes ; and while we have quite strong arguments about our universe having same physical laws almost everywhere, we have no similar arguments for multiverse, so generalizing based on finite subset is unlikely to bring useful answers.)

5 hours ago, ChronosCat said:

Granted this isn't a great example of technology made possible by knowing advanced physics (as we probably could have brute-forced it without knowing the underlying theory)

As proved by brute-forcing the Higgs boson. Seriously, we had no idea how much energy it will have before we found it.

5 hours ago, ChronosCat said:

it was just the first thing to come to mind. A better example might be quantum computers, but they haven't come into their own yet so it's hard to say just how much of a game changer they'll be.

Considering quantum computers are expected to solve several NP problems in polynomial time, namely RSA, Diffie–Hellman, and elliptic curve Diffie–Hellman, the main game changer issue here would be that anyone with sufficiently good quantum computer can hack rest of world. I mean, sure, quantum-safe algorithms are being developed, but somehow I don't think they will get widely used before the problem show itself to be real.

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18 hours ago, ChronosCat said:

I'm saying that if we didn't know about relativistic time dilation (but it did exist), GPS wouldn't work properly until the people developing it figured out how to compensate.

I met a guy, long ago, pre-GPS, that was factoring in relativity adjustments for satellite tracking to then existing orbital tracking equations.

18 hours ago, ChronosCat said:

Granted this isn't a great example of technology made possible by knowing advanced physics (as we probably could have brute-forced it without knowing the underlying theory), it was just the first thing to come to mind. A better example might be quantum computers, but they haven't come into their own yet so it's hard to say just how much of a game changer they'll be.

A bit more mundane is quantum tunneling. Quantum tunneling diode, with their weird "knee" in their response curve, have not taken the world by storm, but they've been available since the 1970s. A bit more germane, perhaps, you don't build modern large scale integrated circuits without taking quantum tunneling leakage currents into account.

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2 hours ago, Darth Fluffy said:

A bit more mundane is quantum tunneling. Quantum tunneling diode, with their weird "knee" in their response curve, have not taken the world by storm, but they've been available since the 1970s. A bit more germane, perhaps, you don't build modern large scale integrated circuits without taking quantum tunneling leakage currents into account.

Hah! You think that's complex? Imagine how it revolutionised the world of carts and wheels when someone worked out how to grease axles!

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16 hours ago, hkmaly said:

Ok, I should've said "Dark Matter and Dark Energy", because I assume it's same unknown.

The leading view among physicists is that Dark Matter and Dark Energy are completely unrelated - but it's certainly quite possible a theory of gravity that works on quantum scales might also account for the phenomena associated with both of them.

16 hours ago, hkmaly said:

Whether we are a part of multiverse is theological question. The physical question you have on mind is if there is way to transfer information, energy and/or matter between our universe and some other universe in the multiverse.

(To be more exact: even if there IS such way, we can only confirm existence of finite amount of other universes ; and while we have quite strong arguments about our universe having same physical laws almost everywhere, we have no similar arguments for multiverse, so generalizing based on finite subset is unlikely to bring useful answers.)

Actually, a more precise version of my question would be: Is it possible to know if we exist within a multiverse (of "real" as opposed to "possible" worlds) and if so, do we?  Transfer of information/energy/matter between worlds would be extremely helpful in determining this (and also would be really cool), but I have heard clams that some theories that predict a multiverse would be possible to test without being able to directly detect other universes.

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7 hours ago, The Old Hack said:

Hah! You think that's complex? (quantum tunneling)

No, once you accept that it happens, it's fairly straight forward.

Side note, I don't design ICs. I've had friends pursue it, but it always struck me as a sucker game. IC design has the shortest lifespan of job knowledge of anything I know; the scales of the component devices has been shrinking rapidly for decades (Moore's "Law"). (In quotes, because if you can't define cause and effect, it isn't really a law.)

My perception is that it is harder to stay employed as an out of date IC designer as opposed to say an out of date medical doctor or machine operator. The profession seems more cut throat and the employers more demanding. To be fair, you're probably in better shape than most for the next go-round of training, but what a hamster wheel!

Is there a floor? Seems like there is, and we are near it, but folks seem to keep pulling rabbits out of that d@#% old hat. We do seem to be slowing down as we reach atomic scale.

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10 hours ago, Darth Fluffy said:
On 9/11/2019 at 6:54 PM, ChronosCat said:

Granted this isn't a great example of technology made possible by knowing advanced physics (as we probably could have brute-forced it without knowing the underlying theory), it was just the first thing to come to mind. A better example might be quantum computers, but they haven't come into their own yet so it's hard to say just how much of a game changer they'll be.

A bit more mundane is quantum tunneling. Quantum tunneling diode, with their weird "knee" in their response curve, have not taken the world by storm, but they've been available since the 1970s. A bit more germane, perhaps, you don't build modern large scale integrated circuits without taking quantum tunneling leakage currents into account.

I already mentioned NAND flash ...

7 hours ago, ChronosCat said:
23 hours ago, hkmaly said:

Ok, I should've said "Dark Matter and Dark Energy", because I assume it's same unknown.

The leading view among physicists is that Dark Matter and Dark Energy are completely unrelated - but it's certainly quite possible a theory of gravity that works on quantum scales might also account for the phenomena associated with both of them.

... ok, my assumption might be incorrect and/or out of date.

7 hours ago, ChronosCat said:
23 hours ago, hkmaly said:

Whether we are a part of multiverse is theological question. The physical question you have on mind is if there is way to transfer information, energy and/or matter between our universe and some other universe in the multiverse.

(To be more exact: even if there IS such way, we can only confirm existence of finite amount of other universes ; and while we have quite strong arguments about our universe having same physical laws almost everywhere, we have no similar arguments for multiverse, so generalizing based on finite subset is unlikely to bring useful answers.)

Actually, a more precise version of my question would be: Is it possible to know if we exist within a multiverse (of "real" as opposed to "possible" worlds) and if so, do we?  Transfer of information/energy/matter between worlds would be extremely helpful in determining this (and also would be really cool), but I have heard clams that some theories that predict a multiverse would be possible to test without being able to directly detect other universes.

Hmmm, interesting, didn't account for that possibility. Not sure I believe that claim either.

However, it's still more prove than know if you want non-theological answer. There are much more people knowing God exists than people capable of proving her existence.

22 minutes ago, Darth Fluffy said:

Is there a floor? Seems like there is, and we are near it, but folks seem to keep pulling rabbits out of that d@#% old hat. We do seem to be slowing down as we reach atomic scale.

Yeah, Intel seems to have much bigger issues with each smaller nanometers ... and we do have the same effective speed limit on CPU for several years (and only get more power due to raising number of cores) ... but I also expect someone will came with something allowing to do more steps.

(Also, I'm like imagining the IC designers impatiently kicking heels in the waiting room of LHC and asking the theoretic physicists "so, do you have it?")

22 minutes ago, Darth Fluffy said:

(Moore's "Law"). (In quotes, because if you can't define cause and effect, it isn't really a law.)

Nevertheless, Moore's "Law" may remain true longer than General Theory of Relativity. Or at least longer than Pauli exclusion principle, if we don't simply switch to bosons ...

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9 minutes ago, hkmaly said:

Nevertheless, Moore's "Law" may remain true longer than General Theory of Relativity.

Please expound. Do you mean disproved or superseded?

Edited by Darth Fluffy
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9 minutes ago, Darth Fluffy said:
18 minutes ago, hkmaly said:

Nevertheless, Moore's "Law" may remain true longer than General Theory of Relativity.

Please expound. Do you mean disproved or superseded?

Technically, any exception disproves the theory ; however, I do consider Newton's Theory of Gravity more superseeded than disproved by General Theory of Relativity.

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Newton's theory of gravity is mostly right. Einstein's general relativity is a little more mostly right.

Quantum mechanics is also mostly right. But under certain conditions which we can't currently create and haven't been lucky* enough to observe, quantum mechanics and general relativity make bizarre and wildly-different predictions of what will happen - so they definitely are not both completely right, and it's possible that neither of them is completely right.

* Or unlucky enough to observe, as the creation of those conditions by natural means would probably turn observers at any useful range into disorganized masses of subatomic particles.

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19 minutes ago, Don Edwards said:

Or unlucky enough to observe, as the creation of those conditions by natural means would probably turn observers at any useful range into disorganized masses of subatomic particles.

I don't think so. I think that creating those condition by natural means will turn anyone around into disorganized masses of subatomic particles before they manages to become observer.

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That depends upon the definition of “observer” being used. If we use the quantum mechanical definition of “something which interacts with the quantum mechanical system being described” (e.g. receiving photons emitted from it), then yes, we can still call them observers. If, however, we use the definition of “becoming cognizant of the event”, then no, they will be destroyed before that can occur.

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4 hours ago, hkmaly said:

Technically, any exception disproves the theory ; however, I do consider Newton's Theory of Gravity more superseeded than disproved by General Theory of Relativity.

It's "superseded". I spelled it superceded and got the red underline, so I looked it up. Superceded is also commonly used, but it's incorrect (more than one article said this). Superseeded sound like a farming technique, possibly involving a turbo charged planter or GMO products.

I sort of agree with you that superseded applies to Newton rather than disproved; that we make the distinction says it isn't the same, so the exception is not disproving the theory, rather it is defining the limits of it's usefulness. And Newton still has much usefulness; I do not drag out relativistic equations for how much time I'll need to drive to the mall. We still teach Newtonian mechanics, because they are inherently useful.

So, forgive me for not being excited by the "news" that General Relativity is passe. If something new comes along, it's going to be a refinement of, not a replacement of, General Relativity.

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1 hour ago, Darth Fluffy said:

that we make the distinction says it isn't the same, so the exception is not disproving the theory, rather it is defining the limits of it's usefulness

That we make the distinction says that the language we are using is not formal logic.

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3 hours ago, hkmaly said:

That we make the distinction says that the language we are using is not formal logic.

True, true. We can't all be Sheldon Cooper, as appealing as dysfunctional super intellect is.

Then again, there's still that usefulness and applicability thing, so maybe applying formal logic to this is short sighted?

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18 minutes ago, Darth Fluffy said:

Then again, there's still that usefulness and applicability thing, so maybe applying formal logic to this is short sighted?

Now you have me wondering. Is there such a thing as informal logic? Or is that when the logicians are being really relaxed about things, like, when they just can't be arsed and, oh, gag me with a differential equation it's all just so stilted and why do we even bother we're all friends around here aren't we.

No, I looked it up and there is such a thing as informal logic and it isn't quite what I describe above. Too bad, I rather liked the idea.

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2 hours ago, The Old Hack said:

Now you have me wondering. Is there such a thing as informal logic? Or is that when the logicians are being really relaxed about things, like, when they just can't be arsed and, oh, gag me with a differential equation it's all just so stilted and why do we even bother we're all friends around here aren't we.

No, I looked it up and there is such a thing as informal logic and it isn't quite what I describe above. Too bad, I rather liked the idea.

I'll have to look that up. Not at the moment, have an appointment I need to run off to soon.

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13 hours ago, Darth Fluffy said:

Then again, there's still that usefulness and applicability thing, so maybe applying formal logic to this is short sighted?

Why should applying formal logic lead to any limits in usefulness and applicability? You just need to accept that disproved doesn't mean useless.

Also, technically you can formulate law which is always correct and carries all the practical usability of Newton's gravity law.

Like, "The difference between force and Gm1m2r-2 is smaller than (equation involving gravitational potential ${\displaystyle \phi }$ , speeds v1 and v2 and c)".

Finding out the exact equation will be hard, but you are allowed to use estimates when you compute it, as usually the difference between that and your measurement error will be several magnitudes.

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Native English speaker here; disproved is not the same as superseded nor extended. I won't even give that Newton is wrong (not disproved); as I spend most of my time on the surface of this planet, I generally do not need to account for relativistic effects nor quantum effects in my day to day activities. That's why schools teach statics and dynamics and motors and engines in an Newtonian framework. If that doesn't suit you, you are welcome to formulate your own system that works better, but I'm not going to be sitting, waiting, with high expectations.

Think about why relativistic effects even matter in the special cases. GPS is a locating system. It was developed by the military (US) for targeting purposes. Feet or decimeters matter. And even a small error is cumulative, over the days, months, years that the satellite orbits. (I think they also calibrate themselves against fixed points on the earth, but a relativistic calculation software upgrade would have been a welcome quick fix.)

And so on.  A few specialty jobs deal with this all the time. Most of us can safely ignore non-Newtonian physics, or even be ignorant of it, and still be functional. You didn't create the capability for your cell phone to tell you where you are; some engineer and a software team did. Yet you can use the driving app. Even when you touch on the relativistic or quantum, you are essentially unaware of it. (I expect you now to say, "No, I'm not", and miss the point entirely. Go for it.)

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32 minutes ago, Darth Fluffy said:

Think about why relativistic effects even matter in the special cases. GPS is a locating system. It was developed by the military (US) for targeting purposes. Feet or decimeters matter. And even a small error is cumulative, over the days, months, years that the satellite orbits. (I think they also calibrate themselves against fixed points on the earth, but a relativistic calculation software upgrade would have been a welcome quick fix.)

Small errors are definitely cumulative ... and they would cumulate to 10 kilometers per day, not decimeters. The goal of navigation accuracy of 15 meters requires the clock on satellites having accuracy of 50 nanoseconds, and the size of that small error between Newton and Einstein is 45 microseconds per day for weaker gravity in it's orbit 20,000 km above the Earth AND 7 microseconds per day for their orbital speed of 14,000 km/hr ... but wait, those actually have opposite direction so the total difference is 38 microseconds per day.

I don't think the satellites would be able to calibrate often enough.

39 minutes ago, Darth Fluffy said:

as I spend most of my time on the surface of this planet, I generally do not need to account for relativistic effects nor quantum effects in my day to day activities.

YOU don't. However, you can easily get into situations where they would be measurable. You don't need satellites or military aircraft: you can get measurable time differences on normal watches if you make just few longer airplane trips.

46 minutes ago, Darth Fluffy said:

Native English speaker here; disproved is not the same as superseded nor extended. I won't even give that Newton is wrong (not disproved)

Native Lojban speaker would disagree.

The term "disproved" has specific meaning in science (especially math) which has nothing to do with English.

I though I established the difference between theoretical and practical view clearly. From theoretical point of view, Newton is wrong. From practical, the difference is in most "everyday" cases so small it doesn't matter. Neither of those points of view is more correct than the other ; you need to decide what interest you. You choose practical one, ok ... but don't try to convince others it's only choice.

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6 hours ago, hkmaly said:

Small errors are definitely cumulative ... and they would cumulate to 10 kilometers per day, not decimeters. The goal of navigation accuracy of 15 meters requires the clock on satellites having accuracy of 50 nanoseconds, and the size of that small error between Newton and Einstein is 45 microseconds per day for weaker gravity in it's orbit 20,000 km above the Earth AND 7 microseconds per day for their orbital speed of 14,000 km/hr ... but wait, those actually have opposite direction so the total difference is 38 microseconds per day.

OMG, give yourself a cookie, you found an article with much more accurate numbers than I threw out, but you're still missing the point. In the very article you quoted, it says: "But GPS is an exception" So, go ahead, swallow that camel while straining out the gnat.

6 hours ago, hkmaly said:

I don't think the satellites would be able to calibrate often enough.

Meh, you could probably do so and not have enough overhead to really matter, even at a few minute intervals. I like the approach of doing both; calculate as accurately as possible, and check periodically.

The need to check position is inherent in all dead reckoning navigation. The error is always cumulative. That is why until recently, with the availability of GPS, navigators are all trained in archaic navigational techniques; is probably still a good idea, because that one time you really need it, you can bet that GPS is going to crap out.

(Come to think of it, that's happened to me. I use the Waze app to navigate in my car, if I'm going somewhere unfamiliar. My cell phone has been acting up lately, I need to replace it, will do so soonish. So one time recently, I could not get a signal when I needed to find my way home, so no Waze. I opened a compass app, and went in a useful direction and found a road I knew.)

6 hours ago, hkmaly said:

YOU don't.

No. Most people on the planet don't. Read on.

6 hours ago, hkmaly said:

YOU don't. However, you can easily get into situations where they would be measurable. You don't need satellites or military aircraft: you can get measurable time differences on normal watches if you make just few longer airplane trips.

Again, missing the point. "However, you can easily get into situations where they would be measurable." - yes, but you don't fix it; it's been done for you by a handful of specialists.

Think of it this way, do you fix your own car? I'm odd, I have. I no longer do, I can't afford the time, nor the downtime on the vehicle. I go to a mechanic.

I read health articles. When I'm sick, I go to a doctor. I'm not allowed to prescribe my own medication. I don't want to invest in the expensive and quickly outdated medical equipment.

I like that my cell phone already has corrected GPS coordinates, and I don't have to calculate an offset manually. I think if it did, few people would use GPS.

6 hours ago, hkmaly said:

Native Lojban speaker would disagree.

Oo? That isn't even wrong. Do you know of such a family? I won't argue the hypothetical merits, it just isn't a reality.

6 hours ago, hkmaly said:

The term "disproved" has specific meaning in science (especially math) which has nothing to do with English.

The term "disproved" has specific meaning in different contexts, including science, somewhat different in math, definitely different in court, and so on. Even then, the meaning can be in dispute; for example, do mathematical proofs that are beyond human calculation and require the use of computational hardware to prove count as proved? Regardless of your opinion on the matter, (i.e., I'm not really asking, I'm making a related point), there are competent mathematicians that disagree with you. So the notion that proof means exactly what you think it does is fraught with difficulty. And, unfortunately, it has much to do with the language and culture you express it in, even the subculture within that sphere; if this were not the case, we would not be dealing with the plethora of inane public controversies that we experience on a daily basis.

"Yes, but formal logic always applies". Godel showed why that's wrong, and essentially the same problem keeps cropping up in other fields, in a different guise. But I like this refutation best.

6 hours ago, hkmaly said:

I though I established the difference between theoretical and practical view clearly.

Sorry, man, I don't see that you've even acknowledged the difference, let alone established it.

6 hours ago, hkmaly said:

From theoretical point of view, Newton is wrong.

Yes, I think everyone here understands the framework.

6 hours ago, hkmaly said:

From practical, the difference is in most "everyday" cases so small it doesn't matter.

OK, now I would consider the point acknowledged.

6 hours ago, hkmaly said:

Neither of those points of view is more correct than the other ; ...

Here is where we are parting ways. Context is everything; depending on your context either one is way more correct.

6 hours ago, hkmaly said:

... you need to decide what interest you.

If you mean, you need to choose what context applies, that makes sense.

6 hours ago, hkmaly said:

You choose practical one, ok ...

For the most part, we (big we, all of us, even the astrophysicists drive to work) do not choose; rather, we are born into the milieu; it is the water we swim in, the air we breathe. Our world, our life is Newtonian. The relativistic and quantum effects are imperceptible.

I'm not saying you can't find them if you look for them, just that you won't encounter them unless you do. We are born into a relativistic world, and we are born into a quantum world, neither of which manifest plainly on a daily basis.

6 hours ago, hkmaly said:

... but don't try to convince others it's only choice.

I've been pretty clear that it's not "the only choice", that some specialists have to take relativity and/or quantum effects into account; however, I do not see it so much as a "choice" as tools that may or may not apply to a given situation.

As far as convincing anyone, I really don't give a rats ass. Convincing the delusional is futile, it is wasted effort. I know people who believe the moon landings were faked. Evidence means little to them. Intelujint Dezine? I'd rather argue with the paint on the wall, at least it doesn't say stupid stuff back. We have a "No politics" policy for a reason; people are not generally reasonable.

So actually, please take it as a complement that I'm willing to respond to you. You bring up good points, you are interesting, and I do not mind a different point of view; I've changed my mind often enough.

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GPS is one of the very few things that most people deal with regularly that requires parts-per-trillion precision.

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10 hours ago, Darth Fluffy said:

Think about why relativistic effects even matter in the special cases. GPS is a locating system. It was developed by the military (US) for targeting purposes. Feet or decimeters matter. And even a small error is cumulative, over the days, months, years that the satellite orbits. (I think they also calibrate themselves against fixed points on the earth, but a relativistic calculation software upgrade would have been a welcome quick fix.)

Even if they have perfect adjustment for relativity, they'd still have to recalibrate the satellites periodically. See, there's this thing called the "three-body problem", and even worse, the "n-body problem". Jupiter, Saturn, passing asteroids, and quite a few other things distort the satellites' orbits a tiny bit through ordinary gravitational effects, and that's a complex problem that hasn't been even theoretically solved - for that matter they don't have a sufficiently complete catalog of the bodies they'd need to adjust for either. And GPS is a VERY-high-precision system.