What is gravity?

How does science work? And what's all this about quantum mechanics?

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Cerveny
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Re: What is gravity?

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It is a tension/strain caused by structural defects in growing crystal of history...
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Re: What is gravity?

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Gravity is that weird invisible shit that kills people.

Yes, it really is a hostile universe that doesn't give a flying monkey tree about you and your God stories.
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Re: What is gravity?

Post by RCSaunders »

seeds wrote: Mon Apr 16, 2018 11:37 pm ... gravity?
Gravity is not a thing or even an attribute. It is only an observed phenomena of entities which have momentum. All such entities accelerate towards each other, and that phenomenon is called gravity. If you are going to ask, what is gravity, you have to ask what is mometum--why do bodies remain in motion (at the same speed and direction) unless accelerated? And, since no entity is totally isolated, all entities are constantly accelerated.
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Re: What is gravity?

Post by seeds »

RCSaunders wrote: Wed Jul 15, 2020 1:30 am
seeds wrote: Mon Apr 16, 2018 11:37 pm ... gravity?
Gravity is not a thing or even an attribute. It is only an observed phenomena of entities which have momentum. All such entities accelerate towards each other, and that phenomenon is called gravity. If you are going to ask, what is gravity, you have to ask what is mometum--why do bodies remain in motion (at the same speed and direction) unless accelerated? And, since no entity is totally isolated, all entities are constantly accelerated.
Now of course we’re all just speculating here, but I personally don’t think that your explanation goes deep enough.

And please don’t take that as an insult, because I also don’t think that Einstein’s general relativity goes deep enough either.

The key phrase in your reply is “observed phenomena.”

And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.

In other words,...

(and setting aside the Kantian concept of the noumenon, or the “thing in itself”)

...according to certain interpretations of quantum mechanics, there are no phenomena (at least not as we understand them to be) in the absence of observers to collapse the quantum wave function.

The point is that when it comes to understanding the processes of gravity, I suggest that the key to its workings lies deep within the informational underpinning of the universe – what physicist David Bohm called “the Implicate Order.”

And that is an area that we do not yet fully understand.
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Re: What is gravity?

Post by uwot »

seeds wrote: Wed Jul 15, 2020 4:27 pm
RCSaunders wrote: Wed Jul 15, 2020 1:30 amGravity is not a thing or even an attribute. It is only an observed phenomena of entities which have momentum...
Now of course we’re all just speculating here, but I personally don’t think that your explanation goes deep enough.
Well, RCSaunders is right as far as physics is concerned. Gravity is simply the demonstrable fact that any two massive objects exert an attractive force on each other. When Newton described the force of gravity in the Principia Mathematica, all he did (!) was explain what would be observed. Like you seeds, people at the time, particularly followers of Descartes including Gottfried Leibniz, pointed out that Newton hadn't explained what caused gravity. Nearly 30 years later, when he published a second edition, Newton admitted that he couldn't work out why gravity works. But: "to us it is enough, that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea." https://isaac-newton.org/general-scholium/
seeds wrote: Wed Jul 15, 2020 4:27 pmAnd please don’t take that as an insult, because I also don’t think that Einstein’s general relativity goes deep enough either.
Einstein's General Relativity is based on a model according to which 'spacetime' is a material with physical properties. Specifically, it can be warped by 'matter' and 'energy', as I'm sure you know. So not only is Einstein's maths more accurate, you get a philosophical model thrown in.
seeds wrote: Wed Jul 15, 2020 4:27 pmThe key phrase in your reply is “observed phenomena.”
And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.
The problem is that if it, or its effects aren't observed, who will ever know it ever happened?
seeds wrote: Wed Jul 15, 2020 4:27 pm...according to certain interpretations of quantum mechanics, there are no phenomena (at least not as we understand them to be) in the absence of observers to collapse the quantum wave function.
Leaving aside the event/phenomenon issue, what you are talking about is the Von Neuman-Wigner interpretation and variations thereof, but they are just interpretations. And the meaning of 'observer' is much disputed...
seeds wrote: Wed Jul 15, 2020 4:27 pmThe point is that when it comes to understanding the processes of gravity, I suggest that the key to its workings lies deep within the informational underpinning of the universe – what physicist David Bohm called “the Implicate Order.”
Could be. Whaddya mean by 'information'? If the universe is made of some 'stuff', then anything that is true about that stuff can be defined as information.
seeds wrote: Wed Jul 15, 2020 4:27 pmAnd that is an area that we do not yet fully understand.
It's not alone.
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Re: What is gravity?

Post by RCSaunders »

seeds wrote: Wed Jul 15, 2020 4:27 pm And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.
Good grief, why would your opinion offend me. Don't ever worry about insulting me--it's not possible. We just disagree, or at least do not understand things the same way.

Unless you are mistaking direct perception of a specific event or entity, like the sophist who asks, "how do you know the tree is still there when you are not looking," who himself does not question the existence of any subatomic phenomena which he has never observed, it is difficult to know what you mean.

So my question is what do you mean by, "phenomena that is not observed?" If it's not observed, why would you think there is such a phenomenon. If there is something that is observed from which you deduce or extrapolate the existence of some phenomenon, that phenomenon is an observed phenomenon. If you assume there are some phenomena with no evidence whatsoever that is superstition.

There is no such thing as a phenomenon for which there is no observed evidence, is there?
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Re: What is gravity?

Post by RCSaunders »

uwot wrote: Wed Jul 15, 2020 6:51 pm
seeds wrote: Wed Jul 15, 2020 4:27 pm
RCSaunders wrote: Wed Jul 15, 2020 1:30 amGravity is not a thing or even an attribute. It is only an observed phenomena of entities which have momentum...
Now of course we’re all just speculating here, but I personally don’t think that your explanation goes deep enough.
Well, RCSaunders is right as far as physics is concerned. Gravity is simply the demonstrable fact that any two massive objects exert an attractive force on each other. When Newton described the force of gravity in the Principia Mathematica, all he did (!) was explain what would be observed. Like you seeds, people at the time, particularly followers of Descartes including Gottfried Leibniz, pointed out that Newton hadn't explained what caused gravity. Nearly 30 years later, when he published a second edition, Newton admitted that he couldn't work out why gravity works. But: "to us it is enough, that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea." https://isaac-newton.org/general-scholium/
seeds wrote: Wed Jul 15, 2020 4:27 pmAnd please don’t take that as an insult, because I also don’t think that Einstein’s general relativity goes deep enough either.
Einstein's General Relativity is based on a model according to which 'spacetime' is a material with physical properties. Specifically, it can be warped by 'matter' and 'energy', as I'm sure you know. So not only is Einstein's maths more accurate, you get a philosophical model thrown in.
seeds wrote: Wed Jul 15, 2020 4:27 pmThe key phrase in your reply is “observed phenomena.”
And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.
The problem is that if it, or its effects aren't observed, who will ever know it ever happened?
seeds wrote: Wed Jul 15, 2020 4:27 pm...according to certain interpretations of quantum mechanics, there are no phenomena (at least not as we understand them to be) in the absence of observers to collapse the quantum wave function.
Leaving aside the event/phenomenon issue, what you are talking about is the Von Neuman-Wigner interpretation and variations thereof, but they are just interpretations. And the meaning of 'observer' is much disputed...
seeds wrote: Wed Jul 15, 2020 4:27 pmThe point is that when it comes to understanding the processes of gravity, I suggest that the key to its workings lies deep within the informational underpinning of the universe – what physicist David Bohm called “the Implicate Order.”
Could be. Whaddya mean by 'information'? If the universe is made of some 'stuff', then anything that is true about that stuff can be defined as information.
seeds wrote: Wed Jul 15, 2020 4:27 pmAnd that is an area that we do not yet fully understand.
It's not alone.
Good stuff, uwot.

I have a comment (not a criticism) about this:
Einstein's General Relativity is based on a model according to which 'spacetime' is a material with physical properties. Specifically, it can be warped by 'matter' and 'energy', as I'm sure you know. So not only is Einstein's maths more accurate, you get a philosophical model thrown in.
I've always been sorry about the implied "metaphysics" (philosophical model) of Einstein's theory. It seems unnecessary and a kind of mistake, like earlier aether theories to explain e.m. radiation. The fact the measurable relationships between large massive bodies and high velocities behave, "as if," space were a, "thing," that can be warped does not make it a thing any more than the fact the calculus can be used to treat measurable attributes, "as if," they could be infinitely divided or reduced to the infinitesimal means there are infinite or infinitesimal entities.

One problem with warped space: if space is warped, what is "unwarped" geometry the science of. If the space around a massive body is curved, what is the uncurved thing against which the curved space is compared? o = massive body. | = strait line tanget to the body. ) = curved space around body. 0|) What is the tangent "in" since it would be curved if it was in the space around the body?
(Why is the path of a ray of light passing a large body called curved if there is no straight path to compare it to? If there is a straight path what is it in, since the space around the body is curved?)

I just think space and time are not ontological entities. They are, "things," only in a metaphorical sense and a way of picturing how things behave. I prefer that view because it unloads a lot of metaphysical baggage but does no damage to science or physics.
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Re: What is gravity?

Post by uwot »

RCSaunders wrote: Wed Jul 15, 2020 8:37 pmGood stuff, uwot.
Thank you.
RCSaunders wrote: Wed Jul 15, 2020 8:37 pmI've always been sorry about the implied "metaphysics" (philosophical model) of Einstein's theory. It seems unnecessary and a kind of mistake, like earlier aether theories to explain e.m. radiation.
The advantage with metaphysics/philosophical models is that they can have theoretical consequences that give you something to test. An example is the Michelson Morley test of the luminiferous aether, the null result of which was part of Einstein's inspiration for special relativity.
RCSaunders wrote: Wed Jul 15, 2020 8:37 pmThe fact the measurable relationships between large massive bodies and high velocities behave, "as if," space were a, "thing," that can be warped does not make it a thing any more than the fact the calculus can be used to treat measurable attributes, "as if," they could be infinitely divided or reduced to the infinitesimal means there are infinite or infinitesimal entities.
I agree, and if you look up gravity on wikipedia, you'll see that so do most physicists, as there's something like a dozen theories of gravity which are being seriously investigated. As Richard Feynman says "Any theoretical physicist that's any good knows 6 or 7 theoretical representations for exactly the same physics." https://www.youtube.com/watch?v=NM-zWTU7X-k

RCSaunders wrote: Wed Jul 15, 2020 8:37 pmOne problem with warped space: if space is warped, what is "unwarped" geometry the science of. If the space around a massive body is curved, what is the uncurved thing against which the curved space is compared? o = massive body. | = strait line tanget to the body. ) = curved space around body. 0|) What is the tangent "in" since it would be curved if it was in the space around the body?
(Why is the path of a ray of light passing a large body called curved if there is no straight path to compare it to? If there is a straight path what is it in, since the space around the body is curved?)
Well the classic test of general relativity is the pictures of the 1919 eclipse taken by Arthur Eddington and his team, on the island of Principe. When the position of the stars was compared with those from 6 months earlier, when their light didn't have to pass by the sun, the amount the light was deflected could be measured. It was found to be more consistent with Einstein's warped space model than Newton's vacuum. But, as you point out, it doesn't follow that Einstein's model is therefore correct.
My problem with general relativity is how does matter warp space? But to anyone in the business of say building satellites, that simply isn't a problem.
RCSaunders wrote: Wed Jul 15, 2020 8:37 pmI just think space and time are not ontological entities. They are, "things," only in a metaphorical sense and a way of picturing how things behave. I prefer that view because it unloads a lot of metaphysical baggage but does no damage to science or physics.
Indeed, string theorists can argue with the loop quantum gravity mob all day long. In the meantime, engineers are building and tracking probes and satellites using Newton and Einstein, which for most purposes work very well, but who knows what any of the theories might turn up?
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Re: What is gravity?

Post by seeds »

RCSaunders wrote: Wed Jul 15, 2020 7:48 pm
seeds wrote: Wed Jul 15, 2020 4:27 pm And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.
...Unless you are mistaking direct perception of a specific event or entity, like the sophist who asks, "how do you know the tree is still there when you are not looking," who himself does not question the existence of any subatomic phenomena which he has never observed, it is difficult to know what you mean.

So my question is what do you mean by, "phenomena that is not observed?" If it's not observed, why would you think there is such a phenomenon. If there is something that is observed from which you deduce or extrapolate the existence of some phenomenon, that phenomenon is an observed phenomenon. If you assume there are some phenomena with no evidence whatsoever that is superstition.

There is no such thing as a phenomenon for which there is no observed evidence, is there?
Now I would never assume that I can’t be wrong, but to get the fundamental gist of where I am coming from, then please read my two following (and conjoined) posts to uwot.
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Re: What is gravity?

Post by seeds »

uwot wrote: Wed Jul 15, 2020 6:51 pm Well, RCSaunders is right as far as physics is concerned. Gravity is simply the demonstrable fact that any two massive objects exert an attractive force on each other. When Newton described the force of gravity in the Principia Mathematica, all he did (!) was explain what would be observed. Like you seeds, people at the time, particularly followers of Descartes including Gottfried Leibniz, pointed out that Newton hadn't explained what caused gravity. Nearly 30 years later, when he published a second edition, Newton admitted that he couldn't work out why gravity works. But: "to us it is enough, that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea." https://isaac-newton.org/general-scholium/
By reason of the very explanation you provided above,...

(which is basically just another take on the “shut up and calculate” theme)

...you are simply confirming my suggestion that there is yet a deeper explanation for the workings of gravity.

In which case, I am simply speculating that it might have something to do with, if not quantum entanglement (as was offered in the OP), then some other aspect of the universe’s underlying informational script...

...(kind of like how everything that transpires and is displayed on your computer monitor or television screen when viewing a DVD movie is dependent upon the information encoded on the disk).
seeds wrote: Wed Jul 15, 2020 4:27 pm And please don’t take that as an insult, because I also don’t think that Einstein’s general relativity goes deep enough either.
uwot wrote: Wed Jul 15, 2020 6:51 pm Einstein's General Relativity is based on a model according to which 'spacetime' is a material with physical properties. Specifically, it can be warped by 'matter' and 'energy', as I'm sure you know. So not only is Einstein's maths more accurate, you get a philosophical model thrown in.
“more accurate” yes, but still no bullseye.
seeds wrote: Wed Jul 15, 2020 4:27 pm The key phrase in your reply is “observed phenomena.”

And the problem with it resides in the unresolved issue in physics (and philosophy) of what the status of a phenomenon is when it is not being observed.
uwot wrote: Wed Jul 15, 2020 6:51 pm The problem is that if it, or its effects aren't observed, who will ever know it ever happened?
It’s not a question of whether it happened or not.

It is the question of whether or not in the absence of “conscious” observers, do the “happenings” occur in three-dimensions...

...or...

...do they occur purely in the form of two-dimensional (perhaps, holographic-like) algorithmic processes, churning-away at a deeper level of reality?
seeds wrote: Wed Jul 15, 2020 4:27 pm ...according to certain interpretations of quantum mechanics, there are no phenomena (at least not as we understand them to be) in the absence of observers to collapse the quantum wave function.
uwot wrote: Wed Jul 15, 2020 6:51 pm Leaving aside the event/phenomenon issue, what you are talking about is the Von Neuman-Wigner interpretation and variations thereof, but they are just interpretations. And the meaning of 'observer' is much disputed...
Yes, and I am a firm believer in the idea that any sort of measuring contraption that is constructed from the same fundamental substance as that which it is measuring...

(a contraption that is often referred to as being a form of “observer” in this scenario)

...will be subject to the problem of becoming superpositionally entangled with whatever it is that is being measured, and will simply create a situation where the entire system exists as a more complex field of spread-out (and moving) quantum waves that have no inherent way of collapsing themselves into a positionally-fixed state.

And the point is that a positionally-fixed state of a quantum entity is a condition that is necessary for displaying (or presenting) the 3-D phenomenon that is encoded in the waveform structures.

Hence the “theory” that because the essence of life, mind, and consciousness seems to be so radically different than matter, then it may be what causes the waves to acquire position and thus be the means by which noumena (Bohm’s “Implicate Order”) are transformed into phenomena (Bohm’s “Explicate Order”).

(Continued in next post)
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Re: What is gravity?

Post by seeds »

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(Continued from prior post)
seeds wrote: Wed Jul 15, 2020 4:27 pm The point is that when it comes to understanding the processes of gravity, I suggest that the key to its workings lies deep within the informational underpinning of the universe – what physicist David Bohm called “the Implicate Order.”
uwot wrote: Wed Jul 15, 2020 6:51 pm Could be. Whaddya mean by 'information'? If the universe is made of some 'stuff', then anything that is true about that stuff can be defined as information.
Not meaning to bore everyone with my constant referencing of my own drawings, but when you look at one of my hologram illustrations...

Image

...then the “information” I am referring to (as it pertains to the underpinning of the universe) is metaphorically represented by the square in the middle of the drawing (again, Bohm’s “Implicate” level of reality)...

...with, of course, the laser being a metaphorical representation of consciousness.

Now as a thought experiment,...

(and, needless to say, making the huge assumption that reality is holographic-like in nature)

...if you can just imagine that the die represents the earth of which we are all standing on, and the key represents the moon, and the paper clip represents some other form of space flotsam being attracted to the earth (all up at Bohm’s “Explicate” level of reality)...

...then it becomes clear that everything that we understand reality to be (including the explanation for what gravity is), is all founded upon a deeper matrix of information that seems to work in tandem with consciousness to, again, explicate phenomena from noumena.

Easy peasy. :D
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Re: What is gravity?

Post by commonsense »

:oops:
Last edited by commonsense on Fri Jul 17, 2020 10:33 pm, edited 1 time in total.
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Re: What is gravity?

Post by Sculptor »

seeds wrote: Mon Apr 16, 2018 11:37 pm _______

(Warning – extreme speculation ahead. :))

When it comes to the question of what gravity is all about, is it possible that it has something to do with the superpositioning and entanglement of our quantum underpinning?

For instance, a planet’s gravitational status is based upon its overall mass which, logically (from the quantum perspective), is the sum-total of all of the waveforms of a planet’s contents and features - all blending together into one superpositioned wave.

And when a random asteroid, for example, crashes to a planet’s surface, the asteroid’s wavefunction...

(which up to that moment was basically autonomous in the vacuum of space)

...is now subject to becoming entangled (cohered?) with the planet’s greater wavefunction.

In other words, upon contact with a planet, the asteroid’s wavefunction seamlessly intertwines itself (becomes one) with the planet’s overall wavefunction, thus becoming superpositionally enmeshed with the planet’s phenomenal structures – as is loosely depicted in the right-hand side of my illustration of the laser hologram below...

Image

In which case, the occurrence of what we refer to as being the asteroid’s newly acquired “weight” is something that is proportional to the degree of the entanglement of its own unique waveform constituents with those of the rest of the planet.

And the point is that because the asteroid has a greater array of quantum attributes than that of a feather, for example, it is thus “heavier” than the feather due to a greater complexity of its entanglement with the “whole.”

And all that means is that as we attempt to move or lift the asteroid (or a bowling ball, or a freight train), we are, in essence, “tugging” on a vastly greater web of superpositionally entangled waves than those that comprise the feather...

...hence we therefore encounter a greater resistance to our effort.

Furthermore (and with the help of a rocket), if we were to send the asteroid back into space, it would simply be a situation of detangling (decohering?) its wavefunction from the greater wavefunction of the planet...

(with the degree of detangling still having something to do with distance, as per Newton’s law)

...thus restoring the autonomy of its wavefunction (and its prior weightlessness) in the vacuum.

Now I realize that what I am proposing is highly speculative, however...

...is it possible that the greater the volume and complexity of the entangled morass of quantum waves that comprise a planet’s overall wavefunction is what determines the strength of that which we call a planet’s gravity?
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This is like asking if people's appreciation of the Mona Lisa has something to do with the chemical bonding of titanium lead and linseed oil.
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Re: What is gravity?

Post by uwot »

commonsense wrote: Thu Jul 16, 2020 11:24 pmGravity is the force generated by the electromagnetic attraction between objects.
Try this test: get a magnet, a paper clip and a planet-Earth will do. Put the paper clip on the planet and bring the magnet close to the paper clip. Which wins? The magnetism of a small piece of iron, or the gravity of an entire planet?
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Re: What is gravity?

Post by Impenitent »

would a magnet's strength on another planet vary with the size of the planet? would the chemical make up of said magnet be different?

did magnets react differently on the moon or in outer space?

just a thought...

-Imp
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