Gravity? Did he fall or was he pushed?

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Discussion Overview

The discussion centers around the nature of gravity, specifically whether it can be classified as a pulling force, a pushing force, or neither. Participants explore various theoretical perspectives, including General Relativity and alternative models, while considering implications for understanding gravitational interactions.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that gravity cannot be strictly classified as a push or pull, suggesting it is a result of spacetime curvature as described by General Relativity.
  • Others argue that gravity might be perceived as a pushing force under certain conditions, such as when considering the effects of mass on spacetime.
  • A participant introduces the idea of a "uniform isotropic inertial field" and discusses how the presence of mass modifies this field, leading to different inertial reactions.
  • There is mention of a "pushing gravity theory," which some participants challenge by stating it lacks the rigor of a true scientific theory.
  • One participant questions the perception of force in a two-dimensional analogy, suggesting that a flat being would not perceive the curvature of space affecting its path.
  • Another participant reflects on the relationship between mass and spacetime, pondering whether gravity could be considered a dimension similar to time or space.
  • Some participants express uncertainty about the definitions of "push" and "pull," indicating a need for clearer terminology in the discussion.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether gravity is a push, pull, or neither. Multiple competing views are presented, with ongoing debate about the nature of gravitational interactions and the interpretation of General Relativity.

Contextual Notes

Participants acknowledge that the discussion involves complex theoretical concepts, including the nature of force, the curvature of spacetime, and the implications of mass on gravitational interactions. There are unresolved questions regarding the definitions and interpretations of key terms.

Devilin
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Gravity? Did he fall or was he pushed?
A. relatively simple question, is gravity a pulling force or a pushing force, or both?
 
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Good question - some years ago there was a website that posed the same question and offered some interesting insight - but perhaps it can't really be said to be one or the other - In GR mass conditions spacetime - so another mass feels the gradient (the conditioning brought about by the first mass). Here is another thought - consider a mass in free space that will experience an inertial force when accelerated in any direction - there appears to be a uniform isotropic inertial field that exists throughout the cosmos - now introduce a second mass nearby - when the first mass is accelerated toward the second at a rate equal to the gravitatinal attraction - no force is experienced - if the acceleration is greater than the g force - there will be some inertial reactionary force - but it will be less, etc - so what has happened - the second mass has unbalanced the uniform isotropic inertial field
 
There is a pushing gravity "theory" (in quotes because despite the claims of its proponents, it is NOT a theory). One big problem is there should be no gravity inside your house.
 
Devilin, the answer is: Neither. It is not a push or a pull, because there is no such thing as force. Before you right me off as a kook, I should explain. You see, Einstein postulated General Relativity, and it is the currently accepted theory of gravity (though some do disagree). In General Relativity (GR), what we think of as the "force" of gravity is really just a result of the curvature of spacetime.

In case you haven't heard of anything like this before, I'll post an analogy: Imagine a two-dimensional "flat man", who lives his life out on a piece of paper (which will represent the Universe altogether). Now, let's say that I (three-dimensional God) bend the piece of paper, right in front of where the flat man was about to walk. Obviously, he would move in a "crooked" path, due to the bent nature of the space he's walking on, but as far as he's concerned there must be a force that is either pushing or pulling him to move in that direction.

Does that make sense?
 
Originally posted by Mentat
Devilin, the answer is: Neither. It is not a push or a pull, because there is no such thing as force. Before you right me off as a kook, I should explain. You see, Einstein postulated General Relativity, and it is the currently accepted theory of gravity (though some do disagree). In General Relativity (GR), what we think of as the "force" of gravity is really just a result of the curvature of spacetime.

In case you haven't heard of anything like this before, I'll post an analogy: Imagine a two-dimensional "flat man", who lives his life out on a piece of paper (which will represent the Universe altogether). Now, let's say that I (three-dimensional God) bend the piece of paper, right in front of where the flat man was about to walk. Obviously, he would move in a "crooked" path, due to the bent nature of the space he's walking on, but as far as he's concerned there must be a force that is either pushing or pulling him to move in that direction.

Does that make sense?

Actually...No, it doesn't because the flat man would have NO depth perception, therefore he would not perceive any force holding him to anything that hadn't already/always been there.

(He wouldn't perceive the bend!)

As for Push or Pull force, 3D guys, all energetic activities, from/in nature, are either expansive, or contractive, of space.

EDIT SP!
 
(uniform isotropic inertial field) you've got me there, I've got no idea what your talking about?, could you explain in little words with few syllables? pls :)
As for the space time depression, that was my premise for asking the question, as although gravity itself, its a theoretical and dubious matter, excuse the pun, a submarine when submerged, has the force exerted from the outside pushing inward, wouldn't this Principal be exactly the same in space time itself? and the reason you wouldn't float in zero gee in your house, is the dent in space time, would be a multi dimensional affair,? could gravity be a dimension? Like time or space?
Assuming of course there's no little gravity particles flying around, because of course if there was, Newton's law would mean there's anti gravity particles flying around as well, unless you use this theory for the increasing expansion of the universe itself
Or maybe I'm just talking rubbish? Enlightened me please
 
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Devilin: Perhaps it would help if you gave a PRECISE definition of the "Push" and "Pull".
 
Devlin - when I refer to a uniform isotropic inertial field - it is simply a way of describing the experimental fact that wherever a mass is located - it experiences the same inertial reaction no matter in which direction it is accelerated (isotropic) - whatever it is that produces inertia, it appears to have the same value throughout the universe (uniform) - but that all gets modified in the presense of a second mass - whatever the nature of the field - it gets modified by other matter - the proverbeal concept of a field is that it has properties associated with different locations - Einstein renamed the either spacetime - and he asserted that this spacetime gets conditioned by the presence of other material bodies that exhibit mass-energy. (Does that help).
 
Originally posted by HallsofIvy
Devilin: Perhaps it would help if you gave a PRECISE definition of the "Push" and "Pull".
Personally I've always assumed, that a object if containing enough mass would pull other objects towards it, the mass itself being the pulling object, although now I've reached a uneasy conclusion that the mass of a object, purchase space time onto a object

yogi thanks, if my tiny brain has perceived this correctly, which I seriously doubt it has, I'll need to think on this and I assumed isotropic was a form of energy drink
 
  • #10
Originally posted by Mentat
Devilin, the answer is: Neither. It is not a push or a pull, because there is no such thing as force. Before you right me off as a kook, I should explain. You see, Einstein postulated General Relativity, and it is the currently accepted theory of gravity (though some do disagree). In General Relativity (GR), what we think of as the "force" of gravity is really just a result of the curvature of spacetime.

In case you haven't heard of anything like this before, I'll post an analogy: Imagine a two-dimensional "flat man", who lives his life out on a piece of paper (which will represent the Universe altogether). Now, let's say that I (three-dimensional God) bend the piece of paper, right in front of where the flat man was about to walk. Obviously, he would move in a "crooked" path, due to the bent nature of the space he's walking on, but as far as he's concerned there must be a force that is either pushing or pulling him to move in that direction.

Does that make sense?

No, gravity is not a perceived state, it is a real state, and although the word force might not be a appropriate word, there is definitely something forcing ( pulling/pushing) me towards the ground, and although I assume this is a result of the curvature of spacetime. a action, or reaction ( force ) is definitely present, Does that make sense?
 
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  • #11
I'd say gravity is a pulling interaction, although in relation to things with NEGATIVE mass/energy it might act as a pushing one.
 
  • #12
Standing on the surface of the Earth and being accelerated in 9.8 G's in a weightless environment feels like the same thing. Logically, this must mean that when you fall towards Earth, let's say from an airplane, you are not feeling any acceleration at all. But you're moving, and picking up speed, still you're not really being accelerated. What's happening here? :)
 
  • #13
What is happening is Einstein's equivalence principle which means an inetrial refernce frame due to gravity is the same as an inertial frame due to accelration which means that all frames are relative as long as you include the correct gravitational field.
 

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