Author Topic: That damn gravity measurement...  (Read 1624 times)

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Offline GlennSpriggTopic starter

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That damn gravity measurement...
« on: August 30, 2020, 01:51:42 pm »
'MY' theory is that 'Gravity' is like the Kinetic/Potential energy of the proverbial 'Big-Bang'!!
We agonize over where it all started. Let's look at a 'Simple' physical construction, where there are two boards, held at a
distance between them. To all intensive purposes, between those two boards, there are two springs attached between them.
ONE has NO spring tension, and the OTHER has a 'force' trying to pull them together. All this seems perfectly feasible, BUT imagine
some external device/meter that you 'point' at it, or wave it around, that can measure/detect these forces??  You can't.

It's at(within) an atomic/molecular level. Your 'sensors' need to be within the atomic structure!!  To my mind, it's LIKE that, when
people keep trying to 'measure/detect' Gravity Waves. It's a lost cause. I 'think' that possibly Gravity can only exist, as we know
it & imagine it, is because originally, ALL matter/energy was initially emanating from that single point at creation...  :-//
Imagine the Conundrum of 2 objects/matter 'materializing' in Space. Would the 'force' between them be instantaneous??, or
maybe have to travel at the "speed of light" or something first?  Hang on, it's said that energy can not be created or destroyed, but
only transformed from one form to another or from one object to another...  Yep. I propose also that matter is but a 'form' of energy!

'Matter' has been converted to energy as in E = MC2 in nuclear explosions. And vast amounts of Energy have, in particle accelerators
or atomic 'splitters' resulted in the re-creation of matter (Protons) as well as other 'particles'. So if matter is a form of energy, then it's
not a big leap to imagine the 'Big-Bang' (the source of it all!) to change how we 'try' to compartmentalize 'Gravity'. OK I'm done...   8)
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 

Offline ChristofferB

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Re: That damn gravity measurement...
« Reply #1 on: August 30, 2020, 02:12:39 pm »
Expressing matter in terms of energy and vice versa is completely physically justified and has been routinely exploited for a century. I have no idea what you're trying to say about gravity however, I'm afraid.
--Christoffer //IG:Chromatogiraffery
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Offline Domagoj T

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Re: That damn gravity measurement...
« Reply #2 on: August 30, 2020, 02:12:47 pm »
Why do you capitalize and put random words between apostrophes? What is the meaning of that?
Anyway...
Quote
To all intensive purposes, between those two boards, there are two springs attached between them.
ONE has NO spring tension, and the OTHER has a 'force' trying to pull them together. All this seems perfectly feasible, BUT imagine
some external device/meter that you 'point' at it, or wave it around, that can measure/detect these forces??  You can't.
Intents and purposes...
What do you need the first spring for, then? As for the second one, crude and not quite accurate analogy, but ok for lay discussion. Anyway, we can point or wave around a device that will measure
that force (well, maybe not a gravitational pull of a board, but something larger). Gravimeters are devices that measure gravitational pull directly.

Quote
It's at(within) an atomic/molecular level. Your 'sensors' need to be within the atomic structure!!
Go to your bathroom scale. Is that subatomic device? No. Effects of gravity are most certainly evident on scales much larger than subatomic.

Quote
To my mind, it's LIKE that, when
people keep trying to 'measure/detect' Gravity Waves. It's a lost cause.
Gravity waves have been detected and measured repeatedly. Measurements are in line with theoretical calculations. Far from lost cause.

Quote
I 'think' that possibly Gravity can only exist, as we know it & imagine it, is because originally, ALL matter/energy was initially emanating from that single point at creation... 
Any reason why you think that?

Quote
Imagine the Conundrum of 2 objects/matter 'materializing' in Space. Would the 'force' between them be instantaneous??, or maybe have to travel at the "speed of light" or something first? 
It would travel at the speed of light. This was also measured and observed.

Quote
Hang on, it's said that energy can not be created or destroyed, but only transformed from one form to another or from one object to another...  Yep. I propose also that matter is but a 'form' of energy!
I don't see how is this related to your previous sentence, but in any case, you're not the first to propose that. Energy is routinely transformed into matter (actually matter + as much antimatter) in particle accelerators.

Quote
So if matter is a form of energy, then it's not a big leap to imagine the 'Big-Bang' (the source of it all!) to change how we 'try' to compartmentalize 'Gravity'.
That is a non sequitur.
 
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Offline T3sl4co1l

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Re: That damn gravity measurement...
« Reply #3 on: August 30, 2020, 03:12:54 pm »
'MY' theory is that 'Gravity' is like the Kinetic/Potential energy of the proverbial 'Big-Bang'!!

This will require quite a lot of explanation (on your part).  For my part, let me explain why:

There's no energy associated with the Big Bang; or rather it's not so meaningful to speak of, I think.  The apparent expansion or contraction of the universe over time, is simply a side effect of a universe having a more-or-less uniform mass-energy distribution:
https://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric

Energy is conserved for objects in space, but space-time as a whole doesn't need to conserve it.

So, something being "like" the kinetic or potential energy of a spacetime, is at best analogous.  One must define those terms, because they don't apply in the normal way to a spacetime.


Quote
We agonize over where it all started. Let's look at a 'Simple' physical construction, where there are two boards, held at a
distance between them. To all intensive purposes, between those two boards, there are two springs attached between them.
ONE has NO spring tension, and the OTHER has a 'force' trying to pull them together. All this seems perfectly feasible, BUT imagine
some external device/meter that you 'point' at it, or wave it around, that can measure/detect these forces??  You can't.

Well no, these forces* can be measured as surely as any other acceleration can be.  We even carry around accelerometers in our pockets these days!

*A gravitational field is an acceleration field.  Force is only meaningful when a mass is given (F = ma).

If you're trying to measure the gravitational field of a "board" and are having bad luck just because your boards aren't the size of minor asteroids, well, that's your problem -- that's experimental error, not fundamental physics!  (These measurements have indeed been done, with economically sized masses; the error bars aren't fantastic, but the confidence level is quite good nonetheless.)

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 

Online Alex Eisenhut

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Re: That damn gravity measurement...
« Reply #4 on: August 30, 2020, 04:20:27 pm »
page 22

https://apps.dtic.mil/dtic/tr/fulltext/u2/a093780.pdf

I always wanted to build one since the concept seems simple enough.... but it isn't. I don't have the money or skills to pull it off either. At one point I thought I could get all the precision parts needed from old hard drives but even then the measurement itself seems tricky at best.
Hoarder of 8-bit Commodore relics and 1960s Tektronix 500-series stuff. Unconventional interior decorator.
 

Online Alex Eisenhut

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Re: That damn gravity measurement...
« Reply #5 on: August 30, 2020, 09:01:56 pm »
Why do you capitalize and put random words between apostrophes? What is the meaning of that?

That's "his" Style, man.
Hoarder of 8-bit Commodore relics and 1960s Tektronix 500-series stuff. Unconventional interior decorator.
 
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Offline TimFox

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Re: That damn gravity measurement...
« Reply #6 on: August 30, 2020, 10:00:29 pm »
Here's a modern example of the classic Cavendish measurement of the force between two masses:
https://sciencedemonstrations.fas.harvard.edu/presentations/cavendish-experiment
 
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Offline bson

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Re: That damn gravity measurement...
« Reply #7 on: August 31, 2020, 12:42:01 am »
Gravitational waves have already been detected by LIGO.  They see one on average every two months, a total of 11 right now.
 
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Offline GlennSpriggTopic starter

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Re: That damn gravity measurement...
« Reply #8 on: September 02, 2020, 12:52:49 pm »
Why do you capitalize and put random words between apostrophes? What is the meaning of that?

That's "his" Style, man.

 ;D Yep.  ;D
Again, the only intention is emphasis on certain key words, unrelated to specific Grammar, for brief text.
Eg.  If I said, "People think of 'Gravity' in different ways", it's suggestive (my opinion) that we don't know what it really is.  ^-^

Regarding other responses though, I understand the known processes & maths used to measure what we call Gravity as we know it,
however, what I was really talking about is the actual substance (for the want of a better word) that encompasses it!  :scared:

Domagoj T  said in answer to my proposition about two masses materializing in space, and the Force being instantaneous or not...
He said, "It would travel at the speed of light".  So, is he saying that if the two masses appeared in space at the distance from our Sun
to Earth, then for 499 Seconds nothing would happen, and then suddenly start moving together?

But my pondering, (with limited time/space/place for a better analogy), was simply about the actual stuff of Gravity! 
It was not to cause multiple side issues of offense. Have a good day/night to all !!   :-+
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 

Offline Rick Law

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Re: That damn gravity measurement...
« Reply #9 on: September 05, 2020, 12:56:47 am »

'MY' theory is that 'Gravity' is like the Kinetic/Potential energy of the proverbial 'Big-Bang'!!
...

Expressing it as "'Gravity' is like the Kinetic/Potential energy" is incorrect.  One should think of mass as the total energy content.  Kinetic/Potential energy is Mass, and Mass makes Gravity.  So Kinetic/Potential energy make (additional) Gravity.

To clarify the point, I will use a mechanical music box.  A mechanical music box will have greater mass after it was wounded up as compared to before it was wounded up  - The wound up spring has greater mass due to its greater energy.

I don't know how to prove that without a million dollar mass/weight scale, so I will just quote Einstein, "...we are led to the more general conclusion that
- The mass of a body is a measure of its energy-content
; if the energy changes by L, the mass changes in the same sense by L/9×1020, the energy being measured in ergs, and the mass in grammes.
- (other points not quoted - they are not pertinent to the discussion here)
..."
Quoted from the English translation of Einstein's Sep 27, 1905 paper "DOES THE INERTIA OF A BODY DEPEND UPON ITS ENERGY-CONTENT?"
https://www.fourmilab.ch/etexts/einstein/E_mc2/e_mc2.pdf


...
Quote
It's at(within) an atomic/molecular level. Your 'sensors' need to be within the atomic structure!!
Go to your bathroom scale. Is that subatomic device? No. Effects of gravity are most certainly evident on scales much larger than subatomic.
...

Actually working out Gravity at the subatomic level is a problem.  Relativity doesn't work with Quantum Mechanics, so we will have a hard time designing any sensor in the sub-atomic level and have the sensor being gravity related.

 

Offline Brumby

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Re: That damn gravity measurement...
« Reply #10 on: September 05, 2020, 04:37:57 am »
Why do you capitalize and put random words between apostrophes? What is the meaning of that?

That's "his" Style, man.

 ;D Yep.  ;D
He has become a little more subdued since first posting, but it's just how he rolls.  Indeed, it is his style.
 
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Offline GlennSpriggTopic starter

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Re: That damn gravity measurement...
« Reply #11 on: September 05, 2020, 12:36:57 pm »
Why do you capitalize and put random words between apostrophes? What is the meaning of that?

That's "his" Style, man.

 ;D Yep.  ;D
He has become a little more subdued since first posting, but it's just how he rolls.  Indeed, it is his style.

Hi Brumby.  Yea, I think I've mellowed it a bit, haha...  BTW I don't have a problem with Alex saying... "That's "his" Style, man", in fact I like
it! However, notice how he used quotes around the word "his". Maybe he was taking the piss, but that's alright.   ;D
Lately, I've been putting some key word or questionable word in italics, but it has the same intention!  ^-^
Diagonal of 1x1 square = Root-2. Ok.
Diagonal of 1x1x1 cube = Root-3 !!!  Beautiful !!
 


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