Anyone here interested in General Relativity, or perhaps physics in general?

[Abandoned Character]

So I have a project that has been eating away at my soul for the better part of two, almost three, years. I have to write a report that essentially summarizes the basics of general relativity and its philosophical and historical foundations.

If there is anyone else out there that enjoys learning about physics can maybe help me by engaging in a dialogue about the subject. You see, I'm finding it incredibly hard to write by myself and I figure maybe a dialogue would help get my thoughts out of my brain.

For the sake of the layman, I'll give an intro to the topic at hand: Formulated in 1915, General Relativity is the product of Albert Einstein's decade long investigation of the nature of gravity, which lead him to a deep insight regarding both space and time. You may be familiar with the term space-time, which is described exactly as you would expect--the unification of what we percieve to be space and what we percieve to be time.

You may have heard of special relativity, which Einstein formulated well before the general counterpart. The key differences between the two is that special relativity is only concerned with geometrically flat spacetime (spacetime having a geometry is a crazy concept to grasp, but I believe anybody can understand it), whereas general relativity is concerned with flat and curved geometries (such as the discussion of distant light bending around our sun).

Of course, there are limitations to the theory as often emphasized when trying to understand very very small phenomona. This part is a weak spot of mine, as I do not have a super good understanding of why general relativity fails to describe quantum phenomona. The most I can say is that general relativity seeks to create a continuum of spacetime, where as quantum theory chops up reality into very discrete bits.

There are also several other theories of gravity that look to describe what general relativity fails to do. Of particular interest to me is Julian Barbour's construction of Shape Dynamics, which takes the fundamental relations of shape and geometry and makes them the only thing to consider. Barbour does a great job at identifying the failure of general relativity by discussing reference frames and, in particular, inertial reference frames and the ultimate non-inertial reference frame. (My understanding here is a bit watery so it makes sense if this does not click to you, I need to refine this part for myself)

Anyway, I've kind of word-vomitted here. Please let me know if something confuses you, or you have a question, or something fun to add. Whatever it is, I am happy to hear. Thanks.

 

[alltoomuch2]

So I have a project that has been eating away at my soul for the better part of two, almost three, years. I have to write a report that essentially summarizes the basics of general relativity and its philosophical and historical foundations.

If there is anyone else out there that enjoys learning about physics can maybe help me by engaging in a dialogue about the subject. You see, I'm finding it incredibly hard to write by myself and I figure maybe a dialogue would help get my thoughts out of my brain.

For the sake of the layman, I'll give an intro to the topic at hand: Formulated in 1915, General Relativity is the product of Albert Einstein's decade long investigation of the nature of gravity, which lead him to a deep insight regarding both space and time. You may be familiar with the term space-time, which is described exactly as you would expect--the unification of what we percieve to be space and what we percieve to be time.

You may have heard of special relativity, which Einstein formulated well before the general counterpart. The key differences between the two is that special relativity is only concerned with geometrically flat spacetime (spacetime having a geometry is a crazy concept to grasp, but I believe anybody can understand it), whereas general relativity is concerned with flat and curved geometries (such as the discussion of distant light bending around our sun).

Of course, there are limitations to the theory as often emphasized when trying to understand very very small phenomona. This part is a weak spot of mine, as I do not have a super good understanding of why general relativity fails to describe quantum phenomona. The most I can say is that general relativity seeks to create a continuum of spacetime, where as quantum theory chops up reality into very discrete bits.

There are also several other theories of gravity that look to describe what general relativity fails to do. Of particular interest to me is Julian Barbour's construction of Shape Dynamics, which takes the fundamental relations of shape and geometry and makes them the only thing to consider. Barbour does a great job at identifying the failure of general relativity by discussing reference frames and, in particular, inertial reference frames and the ultimate non-inertial reference frame. (My understanding here is a bit watery so it makes sense if this does not click to you, I need to refine this part for myself)

Anyway, I've kind of word-vomitted here. Please let me know if something confuses you, or you have a question, or something fun to add. Whatever it is, I am happy to hear. Thanks.wi

I will definitely read this more carefully later as I think it will interest me. My physics level of knowledge is basic school level many years ago but I'm looking for a new interest and this could be it

 

[Leiot]

I've heard people try to integrate Quantum Mechanics and philosophy but never GR. Sounds interesting. When you said you've been working on a report, are you talking about a thesis?

Back in the day (1800s) physics was called Natural Philosophy so they agreed with you.

Maybe take the math out of it. QM sounds like philosophy if you take the math out of it; e.g.; By looking at something you've changed it; that sort of thing. GR has universal constants (c), objects can bend reality, time isn't a constant, everything is connected to everything else, etc.

Have you read any of Lisa Randall's stuff? She has the simplest description of higher order spatial dimensions I've ever read. She may have some stuff that could apply.

My personal view is that all physics is really is a model that describes reality. It may or may not be what's really there. A good example of that is the Bohr model of the atom. You have a distinct nucleus, electron shells, all of that. Not even close to what's there. But it explains everything you'd want to know in chemistry. GR could be the same thing. People may not be able to integrate QM & GR because one (or both) of them are just wrong, or more likely incomplete. But that doesn't change the fact that relativity has been measured accurately - GPS doesn't work unless you take it into account.

Philosophy is the same thing. It's something that tries to explain reality and our place in it.

Anyway, just babbling here. Let me know what you come up with.

 

[alltoomuch2]

I've heard people try to integrate Quantum Mechanics and philosophy but never GR. Sounds interesting. When you said you've been working on a report, are you talking about a thesis?

Back in the day (1800s) physics was called Natural Philosophy so they agreed with you.

Maybe take the math out of it. QM sounds like philosophy if you take the math out of it; e.g.; By looking at something you've changed it; that sort of thing. GR has universal constants (c), objects can bend reality, time isn't a constant, everything is connected to everything else, etc.

Have you read any of Lisa Randall's stuff? She has the simplest description of higher order spatial dimensions I've ever read. She may have some stuff that could apply.

My personal view is that all physics is really is a model that describes reality. It may or may not be what's really there. A good example of that is the Bohr model of the atom. You have a distinct nucleus, electron shells, all of that. Not even close to what's there. But it explains everything you'd want to know in chemistry. GR could be the same thing. People may not be able to integrate QM & GR because one (or both) of them are just wrong, or more likely incomplete. But that doesn't change the fact that relativity has been measured accurately - GPS doesn't work unless you take it into account.

Philosophy is the same thing. It's something that tries to explain reality and our place in it.

Anyway, just babbling here. Let me know what you come up with.

Keep babbling. I'm enjoying it :-)

 

[Leiot]

I haven't thought about any of this in a long time. Yeah, what Einstein figured out was in one way brilliant and in another way so simple that anyone should have figured it out. He just asked questions and didn't take what was accepted as 'truth'. In that way he was no different than any of the philosophers that came before him.

Ha! I remember I told one of my professors that I put Dark Matter right up there with the Luminiferous Aether. That didn't go over well at all. (I have a pretty strong sarcastic streak) Let's see.. there's some mysterious stuff that doesn't interact with light but most of the matter in the universe is made up of it, and they came up with this because of seeing space-time seemed to be bent without anything being there. But who says space is flat to begin with? We've detected gravity waves, and they bend space-time without anything being there.. Nope. Dark Matter is the answer. Geez..

 

[Abandoned Character]

Going back 300 years to the time of Newton, even he was stumped by the question "how does the information of the mass of the sun reach the gravitationally bnound earth?" Perhaps he and his colleagues were distracted by his (and Leibniz's) invention of calculus and its application to the theory of gravity. Newton essentially said "it is left as an exercise to the reader to figure out how our planet knows of the sun's presence." It wasn't until Einstein when someone decided to tackle the problem. And Einstein was not a self-made man by any means, there's an interesting story of the many characters that underpin his success.

Have you read any of Lisa Randall's stuff? She has the simplest description of higher order spatial dimensions I've ever read. She may have some stuff that could apply.

I am not familiar with Lisa Randall, but she is definitely familiar--probably heard her talk cosmology in some documentary. Could you find a quote or a source I can look up to read her interpretations?

 

[Leiot]

Lisa Randall - Wikipedia

en.wikipedia.org

I first found her after reading Warped Passages.

 

[ZeroM24]

The physical laws frighten and confuse me. This universe is so unimaginable big, cold and lonely. Like a physical representation of the average human soul and mind.

 

[DarkRange55]

So I have a project that has been eating away at my soul for the better part of two, almost three, years. I have to write a report that essentially summarizes the basics of general relativity and its philosophical and historical foundations.

If there is anyone else out there that enjoys learning about physics can maybe help me by engaging in a dialogue about the subject. You see, I'm finding it incredibly hard to write by myself and I figure maybe a dialogue would help get my thoughts out of my brain.

For the sake of the layman, I'll give an intro to the topic at hand: Formulated in 1915, General Relativity is the product of Albert Einstein's decade long investigation of the nature of gravity, which lead him to a deep insight regarding both space and time. You may be familiar with the term space-time, which is described exactly as you would expect--the unification of what we percieve to be space and what we percieve to be time.

You may have heard of special relativity, which Einstein formulated well before the general counterpart. The key differences between the two is that special relativity is only concerned with geometrically flat spacetime (spacetime having a geometry is a crazy concept to grasp, but I believe anybody can understand it), whereas general relativity is concerned with flat and curved geometries (such as the discussion of distant light bending around our sun).

Of course, there are limitations to the theory as often emphasized when trying to understand very very small phenomona. This part is a weak spot of mine, as I do not have a super good understanding of why general relativity fails to describe quantum phenomona. The most I can say is that general relativity seeks to create a continuum of spacetime, where as quantum theory chops up reality into very discrete bits.

There are also several other theories of gravity that look to describe what general relativity fails to do. Of particular interest to me is Julian Barbour's construction of Shape Dynamics, which takes the fundamental relations of shape and geometry and makes them the only thing to consider. Barbour does a great job at identifying the failure of general relativity by discussing reference frames and, in particular, inertial reference frames and the ultimate non-inertial reference frame. (My understanding here is a bit watery so it makes sense if this does not click to you, I need to refine this part for myself)

Anyway, I've kind of word-vomitted here. Please let me know if something confuses you, or you have a question, or something fun to add. Whatever it is, I am happy to hear. Thanks.

I've heard people try to integrate Quantum Mechanics and philosophy but never GR. Sounds interesting. When you said you've been working on a report, are you talking about a thesis?

Back in the day (1800s) physics was called Natural Philosophy so they agreed with you.

Maybe take the math out of it. QM sounds like philosophy if you take the math out of it; e.g.; By looking at something you've changed it; that sort of thing. GR has universal constants (c), objects can bend reality, time isn't a constant, everything is connected to everything else, etc.

Have you read any of Lisa Randall's stuff? She has the simplest description of higher order spatial dimensions I've ever read. She may have some stuff that could apply.

My personal view is that all physics is really is a model that describes reality. It may or may not be what's really there. A good example of that is the Bohr model of the atom. You have a distinct nucleus, electron shells, all of that. Not even close to what's there. But it explains everything you'd want to know in chemistry. GR could be the same thing. People may not be able to integrate QM & GR because one (or both) of them are just wrong, or more likely incomplete. But that doesn't change the fact that relativity has been measured accurately - GPS doesn't work unless you take it into account.

Philosophy is the same thing. It's something that tries to explain reality and our place in it.

Anyway, just babbling here. Let me know what you come up with.

Formulated in 1915, General Relativity is the product of Albert Einstein's decade long investigation of the nature of gravity, which lead him to a deep insight regarding both space and time. You may be familiar with the term space-time, which is described exactly as you would expect--the unification of what we percieve to be space and what we percieve to be time.

This doesn't really discuss the philosophy side of special relativity, which is that all observers in static reference frames should measure the same physical laws and the same speed of light. Einstein started from that philosophical position, and derived special to relativity from that.

You may have heard of special relativity, which Einstein formulated well before the general counterpart. The key differences between the two is that special relativity is only concerned with geometrically flat spacetime (spacetime having a geometry is a crazy concept to grasp, but I believe anybody can understand it), whereas general relativity is concerned with flat and curved geometries (such as the discussion of distant light bending around our sun).

General relativity takes into account accelerated reference frames, and treats gravity as a warping of spacetime and as the equivalent of acceleration.
(I agree with Einstein, except that I see gravity as 'softening' space rather than warping it. As far as I can tell, these are mathematically the same, but warping goes to infinity at an event horizon, while softening goes to a stiffness of zero at an event horizon, which leaves open several reasonable possibilities for how it behaves beyond the event horizon).

Of course, there are limitations to the theory as often emphasized when trying to understand very very small phenomona. This part is a weak spot of mine, as I do not have a super good understanding of why general relativity fails to describe quantum phenomona. The most I can say is that general relativity seeks to create a continuum of spacetime, where as quantum theory chops up reality into very discrete bits.

QM treats time as an absolute reference frame to all observers, while GR treats it as being a relative reference frame that can be different to different observers.

There are also several other theories of gravity that look to describe what general relativity fails to do. Of particular interest to me is Julian Barbour's construction of Shape Dynamics, which takes the fundamental relations of shape and geometry and makes them the only thing to consider. Barbour does a great job at identifying the failure of general relativity by discussing reference frames and, in particular, inertial reference frames and the ultimate non-inertial reference frame. (My understanding here is a bit watery so it makes sense if this does not click to you, I need to refine this part for myself)

I have heard of Julian Barbour, but I have not studied his work.

Have you read any of Lisa Randall's stuff? She has the simplest description of higher order spatial dimensions I've ever read. She may have some stuff that could apply.

I have read a few articles about her, but I don't think I've seen her simple description of higher-order spatial dimensions.

All physics may really just be a model that describes reality. It may or may not be what's really there. A good example of that is the Bohr model of the atom. You have a distinct nucleus, electron shells, all of that. Not even close to what's there. But it explains everything you'd want to know in chemistry. GR could be the same thing.

Or QM could be the same thing, or both could be the same thing. And I'm not all that sure Bohr was 'wrong'. I suspect that in an Omniverse view, Bohr is quite close to right.

There's some mysterious stuff that doesn't interact with light but most of the matter in the universe is made up of it, and they came up with this because of seeing space-time seemed to be bent without anything being there.

Space is more bent than the matter that we can see can account for based on what we know about gravity. One explanation for that is some unseen type of matter.

But who says space is flat to begin with? We've detected gravity waves, and they bend space-time without anything being there.. Nope. Dark Matter is the answer. Hmm.

I keep an open mind on dark matter. "Yet another particle" may turn out to be correct, but it is probably the least interesting of the possible solutions.

 

[alienfreak]

I am interested in it and did coursework on it a long time ago, along with quantum mechanics, but it is all fuzzy in my head now.

The interpretations of quantum mechanics may be relevant: i wonder, if 'many worlds' is true for example, what does that mean for general relativity (or vice versa)? I suppose that interpretation of QM would lose its justifications if general relativity were sufficient to describe the phenomena that make QM necessary.

I find this video fascinating, it may give some inspiration:

 

[Abandoned Character]

When you said you've been working on a report, are you talking about a thesis?

I realize I didn't give you a proper answer. Yes, in essence what I am working on is a thesis, but a not-so-serious one. It is the final thing standing in my way of a bachelors degree in physics and really is not much work, but for some reason I've beaten my head against the thought of starting for nearly 3 years now. My first couple posts on this forum likely reference this conondrum, albiet with a stronger tone of self-destructive thinking.

which is that all observers in static reference frames should measure the same physical laws and the same speed of light. Einstein started from that philosophical position, and derived special to relativity from that.

I appreciate your additions, they are important details both simple and very rich. It's fascinating that one can read Einstein's original papers (translated from german) published in 1905 concerning special relativity and he describes exactly this phenomonan. He makes the observation that a magnet in motion and a conductor at rest produces the same phenomona as a magnet at rest and a conductor in motion. Two empricially identical phenomena must be explained by the same ontology, which brings Einstein to special relativity. One struggle I have with this paper is that he effectively pulls the speed of light as constant in vacuum out of his ass. Clearly, it works out, but the inspiration to hold the speed of light as constant is lost on me.

while softening goes to a stiffness of zero at an event horizon

Are these thoughts about softening yours alone or are there others looking at GR similarly?

I find this video fascinating, it may give some inspiration

I do tend to stay away from QM in this project aside from a couple mentions because the scope is already intimidating as is, but I appreciate the input! Lee Smolin does some fascinating work and is quite familiar with Julian Barbour as well--he even name drops him at the end of that video.

As an aside, I distinctly remember the realization of relativity's implications, and it came after being told that gravity is not a force. There is no force of gravity keeping my person attached to this Earth, instead it is the earth itself stopping me from following spacetime's curvature, which would have me accelerate towards the center of the bent spacetime.

 

[DarkRange55]

I realize I didn't give you a proper answer. Yes, in essence what I am working on is a thesis, but a not-so-serious one. It is the final thing standing in my way of a bachelors degree in physics and really is not much work, but for some reason I've beaten my head against the thought of starting for nearly 3 years now. My first couple posts on this forum likely reference this conondrum, albiet with a stronger tone of self-destructive thinking.


I appreciate your additions, they are important details both simple and very rich. It's fascinating that one can read Einstein's original papers (translated from german) published in 1905 concerning special relativity and he describes exactly this phenomonan. He makes the observation that a magnet in motion and a conductor at rest produces the same phenomona as a magnet at rest and a conductor in motion. Two empricially identical phenomena must be explained by the same ontology, which brings Einstein to special relativity. One struggle I have with this paper is that he effectively pulls the speed of light as constant in vacuum out of his ass. Clearly, it works out, but the inspiration to hold the speed of light as constant is lost on me.


Are these thoughts about softening yours alone or are there others looking at GR similarly?


I do tend to stay away from QM in this project aside from a couple mentions because the scope is already intimidating as is, but I appreciate the input! Lee Smolin does some fascinating work and is quite familiar with Julian Barbour as well--he even name drops him at the end of that video.

As an aside, I distinctly remember the realization of relativity's implications, and it came after being told that gravity is not a force. There is no force of gravity keeping my person attached to this Earth, instead it is the earth itself stopping me from following spacetime's curvature, which would have me accelerate towards the center of the bent spacetime.

I appreciate your additions, they are important details both simple and very rich. It's fascinating that one can read Einstein's original papers (translated from german) published in 1905 concerning special relativity and he describes exactly this phenomenon. He makes the observation that a magnet in motion and a conductor at rest produces the same phenomena as a magnet at rest and a conductor in motion. Two empirically identical phenomena must be explained by the same ontology, which brings Einstein to special relativity. One struggle I have with this paper is that he effectively pulls the speed of light as constant in vacuum out of his ass. Clearly, it works out, but the inspiration to hold the speed of light as constant is lost on me.

Counterintuitively the measured speed seemed to be constant in spite of earth's movement being in different directions at different times of the year, so Einstein asked "if it is constant, where does that lead?"

while softening goes to a stiffness of zero at an event horizon
Are these thoughts about softening yours alone or are there others looking at GR similarly?

I have shared them with some colleagues over the years. I do not know if there are others looking at GR similarly.
I would share them more widely but I haven't yet had time to figure out if/how frame dragging works out.

As an aside, I distinctly remember the realization of relativity's implications, and it came after being told that gravity is not a force. There is no force of gravity keeping my person attached to this Earth, instead it is the earth itself stopping me from following spacetime's curvature, which would have me accelerate towards the center of the bent spacetime.

That can also be viewed as an explanation of where the "force" of gravity comes from, if "force" is defined broadly.