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What's Up With Gravity And Spacetime Curvature?

general relativity.

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#35 Moronium

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Posted 25 January 2019 - 05:29 PM

So this is a "question"?

Looks more like an opinion, and a very "sanctimoniously condescending" one at that... If you want people to treat it as a question, it might be a good idea to pose one clearly. It also might be an idea to read more(do "in-depth research"), and talk less. That's honest advice. If you feel like getting huffy about it, that's your problem. :) You can be mad about your ignorance, shout to the heavens, and remain ignorant, or you can put that outrage to use and actually better yourself. Which path do you choose?

 

 

That is an opinion. But that's not what this thread started with, at all.  I'm not sure if you had read any of the thread before pronouncing that the rubber sheet analogy is quite enlightening (or however you put it).

 

I disagree with your opinion on that, sorry.



#36 Moronium

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Posted 25 January 2019 - 05:45 PM

 

This clip is touted on youtube as being the "best explanation of gravity ever!"

 

I pity the poor students who come away from that thinking that they now have a clear visualization of, and a clear understanding of, gravity.

 

Assuming that the physicist I cited (who claims "curved space plays virtually no role in gravity) has any clue as to what he's talking about, it seems to me that, as entertaining as the instructor's "demonstration" is, it is quite misleading.

 

Such demonstrations undermine, rather than enhance, understanding.

 

But, then again, only a social menace like me would question it, I suppose



#37 GAHD

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Posted 25 January 2019 - 05:49 PM

That's cool. I Have bothered to read back a bit and I think this is the closest you came to a succinct question:

 

So "pointing" by "time" in the direction of "down" is ENTIRELY RESPONSIBLE for planets moving, etc., eh? Can anyone make any physical sense (as opposed to graph paper sense) out of this? If so, can you explain it to me? I don't get it, for some damn reason.

 

That needs you to think in 4d space. There's math for it. There are entire degrees around it. English (and all languages I'm aware of) has a lot of difficulty describing it. You're going to have to go read a lot of papers on string theory and brane theory (M theory) to get a grasp on it, as well as be able to do some serious math. If you want "physical sense" instead of "graph paper sense... I assume you mean an analogy, a crutch, instead of math? sure. Bowling ball on a sheet, concentric shells of jello of various viscocity, etc...  

Barring that, you might be able to get a grasp on higher dimensional thinking though one of my favorite youtubers.
What that gets at is, very loosly and as one of those crutches, is that motion though space and time together always adds up to 1. The faster you move in space, the slower you move in time, just being in an acceleration frame in space (near a massive body) is the same as actually moving at a speed in a way. Again, language outside of math is not really equipped to explain that. You need to build up enough tools and crutches to get there. What the guy is getting at with time and direction sounds like a bad way to express that math in english?



#38 Moronium

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Posted 25 January 2019 - 06:19 PM

Well, thanks for the video, but I'm afraid it doesn't elucidate much for me by way of explaining how time "pointing downward" bullies planets around.

 

I don't know if he was right, but some shrink once told me my IQ was 139.996.

 

Given that, obviously my comprehension ability is simply inadequate to understand anything beyond simple arithmetic.


Edited by Moronium, 25 January 2019 - 11:42 PM.


#39 Moronium

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Posted 25 January 2019 - 06:29 PM

I once asked my Mama, "How come I always get F's in school., Mama?"   She said:  "Looky here, moronium-boy, ya just can't put 10 pounds of **** into no 5 pound bucket.  Aint no thang.  Don't worry your pretty little head about it."

 

I said:  "OK, Mama."


Edited by Moronium, 25 January 2019 - 06:33 PM.


#40 Moronium

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Posted 26 January 2019 - 03:58 AM

What that gets at is, very loosly and as one of those crutches, is that motion though space and time together always adds up to 1. The faster you move in space, the slower you move in time, 

 

Yeah, so I hear.  As long as you're absolutely motionless, then you're moving at the speed of light they say.  Through time.

 

Heh, like I said, I am seeking some sort of meaningful physical explanation, not some mathematical abstraction plotted on graph paper with no connection to physical reality.

 

How do you move "through time?"  At the speed of light, no less?  If the claim was that I move one second per second, or one hour per hour, I might be able to make some kinda half-baked sense out of it.  But at the speed of light?  186,000 miles per second?  Hmmmm?  I kinda understand how you can move through space (although not at the speed of light) but time is not space, or anything akin to it.  I dunno, maybe if I get a big enough grandfather clock I can crawl inside the pendulum cabinet and "move through time" that way, eh?


Edited by Moronium, 26 January 2019 - 04:03 AM.


#41 Moronium

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Posted 26 January 2019 - 04:17 AM

This Smolin guy, who complains that physicists have tried to reduce time to a dimension of space, may have a point, eh?

 

Among those things is the idea (that Smolin advances brilliantly and persuasively) that the reason physicists have come to reject the reality of time is that they have been bewitched by the beauty and success of the mathematical models they use into mistaking those models for reality....To think like this, Smolin claims, is to forget, or to deny, that the objects of mathematics – numbers, curves etc – do not exist, whereas physics concerns itself with what does exist, and, in reality, in the domain of things that do exist, time is inescapable. So, he insists: "Useful as mathematics has turned out to be, the postulation of timeless mathematical laws is never completely innocent, for it always carries a trace of the metaphysical fantasy of transcendence from our earthly world."

 

https://www.theguard...e-smolin-review


Edited by Moronium, 26 January 2019 - 04:17 AM.


#42 GAHD

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Posted 29 January 2019 - 08:32 AM

There's that petulance again, "eh." You should spend your time learning the math instead of attempting linguistic shortcuts. Learning the math is already the shortcut: the giants you'll be standing on had to INVENT that math and apply it over several lifespans. It took 80 years for a lot of the practical wide-ranging proof. Close to 100 for the newer proofs like spanking an invisible quark plasma with energies you cannot mentally comprehend outside of math to figure out why frame-dragging is real.

That math is used for so many things to such degrees of accuracy it's downright silly to say it doesn't follow reality. GPS would go miles out of synch every day if the math wasn't true. Cathode-ray displays(I'm old) wouldn't display correctly if the math didn't hold up. Gold would appear like iron or silver if the math didn't hold up. Trying to completely understand it with english terms alone like "down" and "move" is silly. Those words have to be truncated and repurposed BECAUSE reality is more than your(and my) beady-little-eyes, and simian-avoiding-a-tiger brain, is capable of perceiving directly.

Seriously, with how much effort you seem to spend playing with linguistic constructs, you probably could already understand how to use a determinant and take a couple steps towards understanding why "down" "negative" "zero" "motion" "void" etc just cannot encapsulate the understanding you are seeking.
 



#43 ralfcis

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Posted 29 January 2019 - 09:10 AM

I don't have the story straight but I read on the physics stack exchange that the difference in the acceleration/gravity equivalence is that acceleration is local and gravity effects is not. Even though you can mimic 1 g using acceleration in an elevator on earth and in space, they are not actually the same thing. For example if you stand upside down in an elevator hurtling towards earth at 2 g ending up feeling 1 g while standing on the ceiling that's local but there is still gravity's non-local effect that just because you don't feel, isn't still there. I'm sure from this point, things get really weird in relativity. 



#44 ralfcis

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Posted 29 January 2019 - 09:32 AM

Moronium, do you own a VCR or DVD player? Is there a fast forward and play button and maybe even a slow motion button? Well then, now you know what different speeds through time look like. The dopper shift ratio in relativity also allow you to see different relative speeds through time. For a person televising his daily life in a ship approaching you at .6c, his motion picture on your tv will be going at 2 times the time rate your own motion picture would appear on your tv. I'm talking fast forward on your DVD player. His apparent speed through time is 2c, your speed through time is c and if a person was leaving you at .6c, his apparent speed through time would be .5c.

 

It doesn't mean they are actually going at those speeds through time any more than setting your DVD player to fast forward means it's a time machine even though you can watch an hour show in half an hour.  All people within their own frames are going at the speed of light through time which is the play button at normal speed through time. That is c through time. C through time is not the same as c through space. That's one of the reasons I don't buy relativity's idea that time is just another space dimension. All other space dimensions have no rates of space and they have negative directions, yet the time one doesn't? The idea that there is no rate through time is disproven by your VCR. When I saw relativity's definition of time, I knew that's where Einstein went wrong. A bad assumption that gave apparently correct results which then led to the conclusion the assumption must be good.



#45 Moronium

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Posted 29 January 2019 - 11:29 AM

When I saw relativity's definition of time, I knew that's where Einstein went wrong. A bad assumption that gave apparently correct results which then led to the conclusion the assumption must be good.

 

 

What definition are you talking about?  The one where he said that time is what a clock measures?

 

If so, I agree that this was an egregiously inappropriate scientific definition.  It was just this type of positivistic thinking that led to the ill-conceived solipsistic aspects of SR.

 

Einstein took Lorentz's notion of "local time," which Lorentz said was merely a mathematical fiction (with no relation to objective reality) which was useful as a shortcut when performing calcullations, and said it was "true time."  A huge mistake, if you ask me

 

To his credit, by 1920 Einstein had thoroughly renounced positivism as a viable philosophy of science even though he had been a dogmatic adherent in his younger days.


Edited by Moronium, 29 January 2019 - 11:35 AM.


#46 ralfcis

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Posted 29 January 2019 - 12:57 PM

No, what I said in my paragraph: time is no different than a space dimension, there is no rate for time like there is no rate for space (no I'm going 1 mile per mile like there is I'm going 1 sec per sec), time has no direction or flow to the future, time is subjective. So you zero in on that point and ignore everything else I wrote. So next post you'll  bring up the same point again that you have no idea what the speed of light through time means. I just think you like the sound of your own posts and aren't really here for any answers to your rhetorical questions. And then you ask why no one is discussing stuff with you.



#47 Moronium

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Posted 29 January 2019 - 02:41 PM

Seriously, with how much effort you seem to spend playing with linguistic constructs, you probably could already understand how to use a determinant and take a couple steps towards understanding why "down" "negative" "zero" "motion" "void" etc just cannot encapsulate the understanding you are seeking.
 

  

 

GAHD, if you think understanding math explains why "time pointing downward" CAUSES planets to orbit the sun, rocks to tumble down mountains, etc., and if that answer satisfies your definition of "understanding," then by all means suit yourself.

 

Me, I aint interested.  Whatever "sense" that may make from a tautological (mathematical) standpoint, it's not the "understanding I am seeking."

 

I mean, like, just even leave out the "pointing" and "downward" elements and say time causes planets to orbit the sun.  I don't care how many numerals, equal signs, exponents, square roots, etc. that you encase it in, I will never see "time" as being the type of thing that causes matter to move throughout the universe. No matter how exquisite the formulas and calculations appeared to be, that would not enhance my "understanding" of such a claim.


Edited by Moronium, 29 January 2019 - 03:11 PM.


#48 Moronium

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Posted 29 January 2019 - 08:42 PM

KRONOS (Cronus) was the King of the Titanes and the god of time, in particular time when viewed as a destructive, all-devouring force.  He ruled the cosmos during the Golden Age after castrating and deposing his father Ouranos (Uranus, Sky). In fear of a prophecy that he would in turn be overthrown by his own son, Kronos swallowed each of his children as they were born. Rhea managed to save the youngest, Zeus, by hiding him away on the island of Krete (Crete), and fed Kronos a stone wrapped in swaddling clothes....

 

 

 

Kronos was a BAD man, back then.  I hope he has changed.


Edited by Moronium, 29 January 2019 - 08:43 PM.


#49 OceanBreeze

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Posted 30 January 2019 - 12:36 AM

Cathode-ray displays(I'm old) wouldn't display correctly if the math didn't hold up.
 

 

 

 

 The idea that there is no rate through time is disproven by your VCR. 

 

  :daydreaming:



#50 OceanBreeze

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Posted 30 January 2019 - 12:56 AM

 

 

All other space dimensions have no rates of space and they have negative directions, yet the time one doesn't? The idea that there is no rate through time is disproven by your VCR. When I saw relativity's definition of time, I knew that's where Einstein went wrong. A bad assumption that gave apparently correct results which then led to the conclusion the assumption must be good.

 

 

Nothing stops the time dimension from being negative. It is called the past.

 

Minkowski-Diagram-for-Lorentz-Transforma

 

Space dimensions can have rates that have nothing to with time. A locomotive might burn one meter of log per mile, for example.



#51 GAHD

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Posted 30 January 2019 - 01:04 AM

GAHD, if you think understanding math explains why "time pointing downward" CAUSES planets to orbit the sun, rocks to tumble down mountains, etc., and if that answer satisfies your definition of "understanding," then by all means suit yourself.

 

Me, I aint interested.  Whatever "sense" that may make from a tautological (mathematical) standpoint, it's not the "understanding I am seeking."

 

I mean, like, just even leave out the "pointing" and "downward" elements and say time causes planets to orbit the sun.  I don't care how many numerals, equal signs, exponents, square roots, etc. that you encase it in, I will never see "time" as being the type of thing that causes matter to move throughout the universe. No matter how exquisite the formulas and calculations appeared to be, that would not enhance my "understanding" of such a claim.

SO you're not looking to understand, you are just throwing excrement around like a monkey. Gotcha. Go to 4chan. That kind of willful choice towards ignorance is disgusting. :)