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What's Up With Gravity And Spacetime Curvature?

general relativity.

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#18 Moronium

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Posted 22 January 2019 - 10:00 AM

All those are just analogies. It's like giving an amputee crutches and saying they can "walk" now..."close enough"...All in all you are definitely being useful and and asset to yourself and your fellow man. Greatness to behold. :) Keep slugging along on stumps instead of using the crutches, I'm sure you'll do fine.

 

 

Coming from you, GAHD, the snide, passive-aggressive (non) response surprises me.  But, given what else I've seen here, I suppose it shouldn't.

 

Rather than address the substance of my post, you simply suggest that I am a defective menace to society for even asking questions about a clearly unsatisfactory "explanation."  The most wildly misconceived analogy is still "just an analogy."  That does not make it immune from criticism.


Edited by Moronium, 22 January 2019 - 10:06 AM.


#19 Flummoxed

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Posted 22 January 2019 - 11:25 AM

Professor Verlinde is a theoretical physicist who works on gravity. He does some excellent presentations. 

 

The following is one on his view on gravity, it lasts about an hour it might help or confuse you even further.

 

You might like his presentations 


Edited by Flummoxed, 22 January 2019 - 11:26 AM.


#20 GAHD

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Posted 25 January 2019 - 01:57 PM

Coming from you, GAHD, the snide, passive-aggressive (non) response surprises me.  But, given what else I've seen here, I suppose it shouldn't.

 

Rather than address the substance of my post, you simply suggest that I am a defective menace to society for even asking questions about a clearly unsatisfactory "explanation."  The most wildly misconceived analogy is still "just an analogy."  That does not make it immune from criticism.

Like i said in the part you didn't quote: (again, seems to be a pattern developing)

Not my fault you would rather play word and mind games than be productive and actually indicate something that works better. Nice of you to ignore the other ones too, because that's also productive. All in all you are definitely being useful and and asset to yourself and your fellow man. Greatness to behold. :) Keep slugging along on stumps instead of using the crutches, I'm sure you'll do fine.

Odd how that works. I must be off my rocker expecting people to rise to an occasion and be creative and productive instead of petulant. :)

I never got into it before, but I'm curious where the whole "1cm" curvature came from. That seems to me that you have completely mixed up your sources, or pulled it out of your hiney. The curvature is measured in acceleration, not distance. Maybe you should read more and talk less? It's probably a better way to actually understand things, instead of going off half cocked and seeming like the comic relief in a britcom...



#21 Moronium

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Posted 25 January 2019 - 03:52 PM

 

I never got into it before, but I'm curious where the whole "1cm" curvature came from. That seems to me that you have completely mixed up your sources, or pulled it out of your hiney. 

 

I identified the physcist I was citing and posted a link in the initial post.  I'm curious as to why you didn't see that.


Edited by Moronium, 25 January 2019 - 03:53 PM.


#22 Moronium

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Posted 25 January 2019 - 03:59 PM

 

Odd how that works. I must be off my rocker expecting people to rise to an occasion and be creative and productive instead of petulant. :)
 

 

Petulant?  I'm sorry, I didn't realize that the mods on this cite require one to have a theory superior to GR before he is allowed to ask a question about an extremely dubious analogy.

 

Your response to my question, and your defense of that suspect "trampoline" analogy, strikes me as rather weak and as motivated by something other than considered, mature, rational comment, gahd.  Not sure what you're pissed about, exactly, but apparently something.


Edited by Moronium, 25 January 2019 - 04:10 PM.


#23 Moronium

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Posted 25 January 2019 - 04:14 PM

There are plenty of pompous,  arrogant, pretentious posters here who imagine themselves to be geniuses and who sneer, as you do, GAHD, at the poor idiots who have "an IQ a few decimals short of 140."  I just didn't think you were one of them.

 

What's your IQ, by the way?  I bet it's at least 200.  I've yet to see anyone announce their IQ on the internet who had an IQ less than that.


Edited by Moronium, 25 January 2019 - 04:15 PM.


#24 GAHD

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Posted 25 January 2019 - 04:38 PM

I identified the physcist I was citing and posted a link in the initial post.  I'm curious as to why you didn't see that.

Ahh, That's where you got it from. My mistake. Still that's got to be a derived value, and from what I read one you took out of context?? Unsure who/what "The Physicist" is, other than a burning man duo. Not to fall into an argument from authority fallacy but...I have no reason to take them as authority.

If you want to know measured spatial distortion, your best bet is to cut out middle men like that (and me) and go read up on a fancy experiment from a few years ago. Get the actual data, rather than some derived value from arbitrary source. What you're looking for is arcsecond deviation. Remember sin cos tan? Pi? Highschool maths is enough to get the Euclidean values and see why you need tensors to account for the deviation.

 

 

Petulant?  I'm sorry, I didn't realize that the mods on this cite require one to have a theory superior to GR before he is allowed to ask a question about an extremely dubious analogy.

 

Your response to my question, and your defense of that suspect "trampoline" analogy, strikes me as rather weak and as motivated by something other than considered, mature, rational comment, gahd.  Not sure what you're pissed about, exactly, but apparently something.

I'm not acting as mod when I say that. I try to only play with Thor powers in relation to spam.
You also weren't really asking a question, now were you? You just expressed disdain in a petulant manner. :) I kind of see why you did, but you can't really blame anyone for returning it in kind.  I don't mind returning vitriol back unto those who expressed it, it's often the only language they understand, in your case that seems to be accurate, no?

 

There are plenty of pompous,  arrogant, pretentious posters here who imagine themselves to be geniuses and who sneer, as you do, GAHD, at the poor idiots who have "an IQ a few decimals short of 140."  I just didn't think you were one of them.

 

What's your IQ, by the way?  I bet it's at least 200.  I've yet to see anyone announce their IQ on the internet who had an IQ less than that.

 

Yup. You're one of them. Ain't it grand?

Last I tested I was mid 140s. My age bracket dropped it down from the 160s I had as a teen. I test strongest in spatial awareness and logic. There's a reason I say sub140 have trouble grasping things: it's a mindset and amount of accumulated tools rather than just the ability to regurgitate facts. I'm probably guilty of the fact regurgitation a bit myself, but I do try to point people towards the tools themselves rather than the end answer. If you can't build it yourself you cannot understand it, and I assume you and others want to understand the answer not just memorize a fact. Being able to build that answer from the data by nature will propel anyone who can into that category on an IQ test.

 



#25 Moronium

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Posted 25 January 2019 - 04:48 PM

 

You also weren't really asking a question, now were you? 

 

 

 

Which leads me to (rhetorically) ask:  You weren't really reading my posts, now, were you?


Edited by Moronium, 25 January 2019 - 04:58 PM.


#26 Moronium

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Posted 25 January 2019 - 04:54 PM

As far as the "authority" I cited goes, I obviously don't know who he is either.  Nor did I try to "vouch" for him.  I just said things like "according to this guy," and "if this is correct...."

 

I don't to in-depth research before asking a question that occurs to me on this site. I don't come here to play the role of expert. Forgive me for asking questions instead of giving lectures, eh?


Edited by Moronium, 25 January 2019 - 04:54 PM.


#27 GAHD

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Posted 25 January 2019 - 05:12 PM

Which leads me to (rhetorically) ask:  You weren't really reading my posts, now, were you?

Only the ones I bothered to reply to. :) You'll note I pointed out other ways to look at it because there ARE other ways. It's a crutch. If you don't want to do "in-depth research" and/or aquire the mathematical tools to understand raw data...You're essentially refusing to grow or use "legs" in that previous example I gave. There's your crutches: close enough to walking.
I hope you DO go check out the data, learn the math, and become able to understand it. If you don't want to put in that effort though, I don't think there's a way to explain things outside of those crutches. If that's offensive, too bad. Use the outrage for motivation. That's my gift to you and others. :)
 



#28 Moronium

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Posted 25 January 2019 - 05:12 PM

 I do try to point people towards the tools themselves rather than the end answer. If you can't build it yourself you cannot understand it, and I assume you and others want to understand the answer not just memorize a fact

 

 

 

Hmmm, that's kinda strange, given the rapidity with which you condemn a poster for asking questions in an attempt to gain some understanding, and rebuke him for not taking vague, contentless,  conclusory assertions as a satisfactory answer to a sincere question.   I guess I should have "memorized" the pronouncements of the "experts" here and just quit there, eh?



#29 Moronium

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Posted 25 January 2019 - 05:17 PM

If you don't want to do "in-depth research" and/or aquire the mathematical tools to understand raw data...You're essentially refusing to grow or use "legs" in that previous example I gave. There's your crutches: close enough to walking....II hope you DO go check out the data, learn the math, and become able to understand it. If you don't want to put in that effort though, I don't think there's a way to explain things outside of those crutches. If that's offensive, too bad. Use the outrage for motivation. That's my gift to you and others. :)

 

 

OK, please stop now.  The sanctimonious condescension dripping off of you is drowning me.



#30 GAHD

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Posted 25 January 2019 - 05:26 PM

So this is a "question"?

Ya think?  If the entire mass of the earth only "curves" space by 1 centimeter at its circumference, then the rubber sheet visualization is totally inappropriate, as I see it.  That minute "curvature" is not going to "suck objects in" or invariably impose a trajectory on objects.  Does this infinitesimal amount of  "curved space" cause my pencil to rapidly hit the floor every time I drop it?  At that rate, the amount of "curvature" over my floor would be immeasurable.  Makes no sense.

 

The physicist I quoted suggests that it is NOT space curvature, but rather "time pointing downwards" that causes planetary motion.  This makes no practical sense to me whatsoever either.  It may all "sound good," but it comes across as full of sound and fury, signifying nothing.

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?



#31 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.



#32 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



#33 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?



#34 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.