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Mick Harper
Site Admin
In: London
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I've never known einstein to be used as a verb.
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DPCrisp
In: Bedfordshire
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| Dunno why they[positive and negative charges inside atoms/particles]'re stuck together |
'Course, the short answer there is that opposites attract. But in the case of matter and anti-matter (such as familiar electrons, tiny particles with negative charge, versus positrons, tiny particles with positive charge, but only produced under exotic conditions), they say the positive and negative annihilate each other and produce a burst of 'light' (no mass, just energy). There is evidence that this happens, but why not in the case of ordinary charged particles making up ordinary neutral matter? How come a neutron 'contains' a proton and an electron without the charge being annihilated?
{Only mass is annihilated and charge is not mass. There's something to conjure with later.}
Sort of the converse problem is that atomic nuclei are very plussy, self-repelling, so they should disperse and not exist at all. All this sticking together and sometimes flying apart stuff is (supposed to be) governed by the strong and weak nuclear interactions. Without even understanding them, they are clearly all about electricness. And the missing force, things bashing into one another, where plussy-on-the-inside-minussy-on-the-outside atoms push each other around, has to be electrical, too. If gravity is residual electricity, then we have a full set.
And if we can get mystical for a second, it couldn't be any other way. Positive and negative are just opposites or complements: the basis of anything existing at all is the distinction between something and something else. Electric charge is just our name for the fabric of the universe.
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DPCrisp
In: Bedfordshire
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From Newton's Second Law (basically, that F = ma), mass is how hard it is to make something accelerate.
But making things accelerate is the making-things-bash-into-one-another force, which is fundamentally electrical. Pushing something along ultimately means bringing electric charges up close so that other ones are pushed away... so even mechanical forces are about charges responding to changing electric fields... and how hard it is to do that -- the concept of mass itself -- is something about the propagation of electric fields. (Which means there should be a formula for mass in terms of charge and the speed of light.)
Did I mention before: Relativity says mass goes up as speed goes up and that's why nothing can go faster than the speed of light: on reaching that speed, the mass would become infinite. And this is supposed to be corroborated experimentally by particle accelerators. But if you think about it as a six-year-old would, if the thing you're pushing is already going fast, it gets harder and harder to push any faster. When the car you're trying to bump start is going as fast you can run, how much faster can you make it go? Not at all. But you're still trying. So the mass is, to all intents and purposes, infinite. (Similarly, you can't hurt someone who rolls with your punches: he is an immoveable object as far as your efforts are concerned.)
(Is this "apparent" mass any different from the "real" mass? In the "amount of stuff" sense, yes, there seems to be a difference, but for that, we can quickly fall back to saying what there really is is a bunch of electric charges.)
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DPCrisp
In: Bedfordshire
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Maybe Nils Bohr's universe is saved from oblivion because there is so much of it: his electrons radiating away their energy will be picking up energy from their neighbours. But at the edge of the universe? Yes, energy would be radiated away where there is nothing to intercept it.
But is there an edge of the universe? To put it another way, is there anything at the edge of the universe? (My favourite answer) yes and no.
Remember the Oort Cloud that no-one understands? Or the impossible rotating cloud ancestor of the Solar System? It makes some sense to say the Solar System descends from a supernova (hence there being heavy elements here), in which case, while lots of stuff will have been blasted across the galaxy, there will have been some stuff left, running the gamut from standing still to going very fast. Every bit, like a tennis ball in a lob, will have zoomed away to a distance 'equating' to its speed, but then... like a tennis ball in a lob, falling back towards the centre, under gravity (if nothing else). Rather than bouncing like a tennis ball, each bit would swing around the centre of gravity, in its own orbit, and race back toward the top of the lob. (Or shoot through, like the proverbial lift with a shaft all the way through the centre of Earth?) Stuff would be oscillating in and out, as it were, travelling more radially than tangentially. (And the formation of the Solar System is the process of things colliding with each other and the cloud shrinking and heating up and... so on.) The bits that reach farthest from the centre soon turn around and head back in, passing other stuff that is now farthest away...
If the universe is anything like this -- and why not? -- then it can a) have a finite size without having an edge and b) continually recycle the fringes into the interior. So the opportunities for atoms, if they're anything like Nils Bohr's rejected model, to 'evaporate' by radiating away their energy are rather less than might at first appear.
Still, some atoms should 'evaporate' away... but where does their energy go? Dunno. (Microwave background?) But we assume it's around somewhere: that's what conservation of energy means, a most fundamental precept. (Probably couldn't do physics at all without it.) And since we think light can be both particles and waves... and since we think mass and energy are equivalent, inter-changeable... we must entertain the notion that 'lost' energy might eventually be able to re-condense into electric charges/ masses/ particles/ atoms... which means we should give the Steady State Universe another crack of the whip.
I wasn't expecting that one myself... although I have no particular devotion to the Big Bang. I reckon the appearance that there must have been a Big Bang is a necessary consequence of energy being relative (but being a sort of absolutist position, it actually has no place in modern physics!)
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DPCrisp
In: Bedfordshire
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| Does gravity behave differently outside our atmosphere |
Yes and no. According to Newton, the field gets weaker with the square of the distance (3 times farther away, 9 times less force). This works for all the planets. But the bottom of the Challenger Deep or the top of Everest is scarcely any nearer or farther from the centre of Earth than sea level and you'd be hard pressed to notice the difference in strength of gravity. For everyday purposes, the force of gravity is constant, regardless of height. It's all the same rules, but within the atmosphere (nothing to do with the atmosphere per se, but "close to the surface of Earth") we can use a simpler approximation.
| and does electricity behave the same or differently in outer space |
We'd have to assume it's the same.
| According to what we learnt at school, the earth's atmosphere is supposed to be held in place by earth's gravity, rather than vice versa |
Yes, just the same as water flowing to the lowest point.
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DPCrisp
In: Bedfordshire
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| Can I... express my enormous gratitude for providing a rational explanation to something that has bothered me since...well, for a very long time. |
Well, thank you. But I've only gestured in a certain direction.
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DPCrisp
In: Bedfordshire
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I'm pretty sure this is not what the Electric Universe says, by the way. If I understand them-via-Komorikid right, the known universe is like a huge electrical discharge, of unknown origin outside what we can observe. I'm talking about ordinary electric charges inside the known universe. (That's not to say galaxies are not plasma phenomena and stuff like that, but I don't have any big beef with nuclear fusion in stars like they do, f'rinstance.)
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Chad
In: Ramsbottom
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| DPCrisp wrote: | | Can I... express my enormous gratitude for providing a rational explanation to something that has bothered me since...well, for a very long time. |
Well, thank you. But I've only gestured in a certain direction. |
It's the way you tell 'em.
This guy Eric Sabo seems to be on a similar track (I think)...
http://www.howgravityworks.org/
...but after reading it several times, I still don't get his explanation as to why attractiveness is always greater than repulsiveness. - - Your explanation, on the other hand, as to why...
| ...all neutral particles of matter, being made up of not-quite-cancelling electric charges would be attracted together, regardless of the polarity of the residual electric field at any point. |
...was put in such terms that even I could understand it.
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Ishmael
In: Toronto
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| Chad wrote: | | I'm slowly coming to the conclusion that the universe is essentially simple in its complexity and any theory that requires elaborate and convoluted arguments to account for apparent anomalies is likely to be wrong. |
You've just expressed one of the principles we use in Applied Epistemology (though some here object to my formulation, I put it this way):
The truth is simple.
You've no doubt heard of Occam's Razor, which has numerous formulations, all of which essentially say that the simplest explanation that remains consistent with the facts is most-likely to be true. That's well and good. Science has worked by that motto for centruries. Problem is that for any given phenomenon, each successive, workable explanation always appears simplest, affording us the illusion of a thing explained. Each theory competes for our trust only with the comparably inelegant explanations offered by generations past, and always looks good by the comparison. What incentive is there then to overthrow what works?
No incentive.
In fact, modern science generally requires that current ideas first be falsified before work begin on developing an alternative. What works is called truth unless and until problems arise.
The axiom that truth is simple affords every idea a new competitor: A hypothetical, simpler explanation, which the axiom tells us should exist wherever current beliefs are cumbersome. To determine if an idea has such a competitor, we use "The six year old's rule":
No idea makes any sense except a six-year-old could make sense of it.
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Brian Ambrose
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Good on yer Dan for trying, and I don't want to come across as too pessimistic, but the problem with any of these ideas is that they are of necessity severely and obviously limited by the current state of knowledge. Gravity is mysterious, so we can come up with a cunning idea to understand it in terms of other mysterious forces. Yet isn't this just pushing the bubble under the wallpaper around a bit? How do particles exert a force on each other when they're, say, a million miles apart? Really, what is the mechanism? You can talk about curved space 'n all that, but what provides the 'gravity' required to make the picture of curved space work? Why should something move down the slope at all? What about my favourite simple problem, inertia? What the hell is that about?
It seems to me the truth is we don't actually have the faintest clue as to the fundamentals that lead to the emergent behaviour of the observable physical universe - we're rather like a child who thinks he knows something about how a computer works because he can move the mouse cursor and click on things. Whether an understanding of the underlying mechanisms will turn out to be intellible at all, let alone to a six year old, is a matter of faith. Not that we have much choice other than to hold to the faith.
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Mick Harper
Site Admin
In: London
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Brian, shouldn't these strictures be better aimed at all those dudes with the telescopes? Isn't it they who have been telling us that these problems have essentially all been solved for decades and (in some cases) for centuries?
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DPCrisp
In: Bedfordshire
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| It seems to me the truth is we don't actually have the faintest clue as to the fundamentals that lead to the emergent behaviour of the observable physical universe |
I agree completely, Bri. Explanations run out eventually and we can't do better than "it just does". I tried to acknowledge that by talking about plussiness and minussiness: we don't know what they are, we just know they're there. But people might get the idea that "positive and negative electric charges" means something technical to the scientists. (As when they say the opening of a duct is narrowed due to ostial stenosis: a claim used like an explanation, but since it means "narrowing of the opening", is nothing of the sort.)
"Why is the most fundamental feature of the universe a loop and what makes it vibrate?"
"It just is and they just do."
"Why are there 11 dimensions?"
"There just are."
'Course, I don't subscribe to this tosh: it used to be that the descriptions we founded our explanations on were getting simpler and simpler, but they've got carried away with themselves. One reason for that seems to be that they're trying to blend quantum mechanics with gravity, or find one in the other.
| Gravity is mysterious, so we can come up with a cunning idea to understand it in terms of other mysterious forces. Yet isn't this just pushing the bubble under the wallpaper around a bit? |
Well, they've been pushing 4 bubbles in the wrong direction (since the 4 fundamental forces don't explain the existence of anything we see around us), so if we can push 4 bubbles into one and start going in the right direction, we'll be doing better.
| How do particles exert a force on each other when they're, say, a million miles apart? |
Or a nanometre apart? I dunno.
| Really, what is the mechanism? |
As I said, we are bound to reach a point where we can only describe the mechanism. That in itself is not a bad thing.
| You can talk about curved space 'n all that, but what provides the 'gravity' required to make the picture of curved space work? Why should something move down the slope at all? |
You mean "I hear what you're saying about the shortest path through space-time being a curve, as we see it, but why is anything travelling this shortest route at all? (And what the hell is an elliptical orbit the shortest path from and to?)" Good question.
| What about my favourite simple problem, inertia? What the hell is that about? |
Another good question. A sort of answer is that it's in the nature of existing at all that there is persistence, a tendency not to change so there is something to act and react, some sense of "alright, give us a chance!". Otherwise there is nothing at all. (Physicists seem to have forgotten to study the world, rather than physics.) But we can delve into the how-hard-it-is-to-make-it-accelerate idea in terms of the fundamentals and see what we come up with. Is it easier if mass is something to do with the "stiffness of the electric field", rather than a standalone parameter?
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Brian Ambrose
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| Mick Harper wrote: | | Brian, shouldn't these strictures be better aimed at all those dudes with the telescopes? Isn't it they who have been telling us that these problems have essentially all been solved for decades and (in some cases) for centuries? |
The plumbers and electricians with the telescopes and the microscopes? Nah, they know their ignorance well enough, and it would only hurt their ego to remind them of it. Applied Epistemologists, on the other hand, love to be reminded that it's all, literally all, up for grabs. If only one were clever enough. Damn.
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Brian Ambrose
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| You mean "I hear what you're saying about the shortest path through space-time being a curve, as we see it, but why is anything travelling this shortest route at all? (And what the hell is an elliptical orbit the shortest path from and to?)" Good question. |
Yes, and as someone once (dunno who) pointed out, a satellite should be following the shortest path through space. But actually, it doesn't, since there is always a shorter path between any two points on its path. But my mind is vexed with simpler problems than these. Thanks to Albert, we have this curvy rubber sheet with a big dip in the middle of it due to a planet and we say, see, look how gravity works, the object doesn't fall it just follows the rubber sheet. Duh? Why? What makes it roll down the sheet? There's no gravity, acting perpendicularly to the sheet, in this gravityless space time structure thingy. So why doesn't the object just stay where it is, half way down the slope? So, there is still a mysterious something to invoke even in the rubber sheet explanation of gravity. If you see what I mean. And I understand it's only meant to be a model of the curvature of space, but what sort of model can claim to work if it deceptively leaves out a fundamental component?
| Is it easier if mass is something to do with the "stiffness of the electric field", rather than a standalone parameter? |
Unfortunately no, because 'electric field' is also a thoroughly mysterious, not to say magical, effect. I guess I'm saying that we have reached a point where we cannot explain these mysterious forces in terms of each other; this is just pushing the bubble around. We need an understanding of the underlying energy grid that gives rise to these apparently magical effects and provides the illusion of particularity (if that's a word).
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Grant
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A hypothetical, simpler explanation, which the axiom tells us should exist wherever current beliefs are cumbersome. To determine if an idea has such a competitor, we use "The six year old's rule":
No idea makes any sense except a six-year-old could make sense of it. |
But isn't this just a creation myth? Maybe the ultimate truths are so complicated we could never understand them. We just amuse ourselves looking at the odd pebble on the seashore, as someone once said.
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