I've found a very comprehensive article describing the 30 year old quest to understand the "proton sea" - a look into the developing ideas of what is actually going on inside the proton:
https://www.quantamagazine.org/protons-antimatter-revealed-by-decades-old-experiment-20210224/
As an alternative to the pion model there is a...
However, the two models don't make identical predictions.
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Don't knock spacetime - it is very resilient! 
Look at the Einstein Field Equation which is shown in simplified form in the attachment.
The left hand side 'G' symbol represents how spacetime is warped or curved by matter and energy.
On the right hand side of the equation, the 'T' symbol is the stress-energy tensor.
The stress 'T' on spacetime has to be extremely large to produce an appreciable amount of warp or curvature 'G'.
It takes an object like the Earth (all 6 trillion trillion kilograms of it) to warp spacetime to a level that we're familiar with - spacetime is very resilient!
My knowledge of the maths behind General Relativity is tantamount to zero, so I extracted the above information from this article:
Just How Resilient Is Spacetime? - Scientific American Blog Network
Look at the Einstein Field Equation which is shown in simplified form in the attachment.
The left hand side 'G' symbol represents how spacetime is warped or curved by matter and energy.
On the right hand side of the equation, the 'T' symbol is the stress-energy tensor.
The stress 'T' on spacetime has to be extremely large to produce an appreciable amount of warp or curvature 'G'.
It takes an object like the Earth (all 6 trillion trillion kilograms of it) to warp spacetime to a level that we're familiar with - spacetime is very resilient!
My knowledge of the maths behind General Relativity is tantamount to zero, so I extracted the above information from this article:
Just How Resilient Is Spacetime? - Scientific American Blog Network
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In his book Far Journeys, Robert Monroe called how our limited senses perceive reality as Time Space Illusion. In a sense it is since physics has begun to consider spacetime as an emergent quantity. Just like we visualize a proton as simply a particle.
Today we still cling to our particle notion with all its weird quantized properties since it is directly useful for our survival; while only a few of us prefer to work in the messy underlying probability function.
The centennial of the Copenhagen Interpretation is coming soon, seems we have some fresh views coming on the table.
Today we still cling to our particle notion with all its weird quantized properties since it is directly useful for our survival; while only a few of us prefer to work in the messy underlying probability function.
The centennial of the Copenhagen Interpretation is coming soon, seems we have some fresh views coming on the table.
Nice way of putting it @indra1
This guy has some great physics lectures - hes go one (2 part) where he derives Einstein's field equations - its about 2 hours long. You come away with a fresh appreciation for just what a breakthrough GR was and Einstein's genius.
General Relativity: An Introduction - Part 1 of 2 - YouTube
This guy has some great physics lectures - hes go one (2 part) where he derives Einstein's field equations - its about 2 hours long. You come away with a fresh appreciation for just what a breakthrough GR was and Einstein's genius.
General Relativity: An Introduction - Part 1 of 2 - YouTube
Some explanation of the term "emergent quantity" may be in order, so here are the fruits of my research.
An emergent quantity is one that can only be inferred from an understanding of the properties of its microscopic constituents.
Spacetime is coming to be regarded, not as something fundamental in itself, but as a quantity emerging from the dynamics of some underlying microscopic theory.
It is thought that spacetime may break down at smaller scales and higher energies than are currently being probed by particle accelerators.
So spacetime is coming to be regarded as an approximation that emerges only at large distances and low energies.
More on emergent spacetime: https://guava.physics.uiuc.edu/~nigel/courses/569/Essays_Spring2018/Files/gupta.pdf
I suspect the appropriate phrase is "emergent quality," though (and perhaps a different but related topic) a significant change in quantity does change quality.
(I'm imagining writing a long post mentioning chaos theory, cellular automata, Conway's Game of Life, Wolfram's infamous NKS ... oh yeah the book is free online but I don't recommend reading past chapter 2, it's just more variations on a theme A New Kind of Science: A 15-Year View—Stephen Wolfram Writings)
Have you seen what Wolfram is up to lately, he's "simulating" the fabric of space, but it's not "just" at the subatomic level, he claims he's doing it at 30 orders of magnitude below the Plank Constant, yes, you read that right ...
(I'm imagining writing a long post mentioning chaos theory, cellular automata, Conway's Game of Life, Wolfram's infamous NKS ... oh yeah the book is free online but I don't recommend reading past chapter 2, it's just more variations on a theme A New Kind of Science: A 15-Year View—Stephen Wolfram Writings)
Have you seen what Wolfram is up to lately, he's "simulating" the fabric of space, but it's not "just" at the subatomic level, he claims he's doing it at 30 orders of magnitude below the Plank Constant, yes, you read that right ...
I used "emergent quantity" to match indra1's post.
The term used in the 2018 Udit Gupta reference is "emergent property" which makes more sense to me - as in 'Spacetime is an emergent property of some underlying microscopic theory.'
The reference also suggested that spacetime 'breaks down' anywhere between the TeV scale and the Planck scale. So it is interesting to hear from you that Wolfram is simulating way down at basement level.
You give me far too much credit!Though I suspect that you or Steve may.
I'm just learning about this right now by looking up references and trying to share my findings in a semi-digestible manner.
As for Steve...
I also see the phrase "emergent behaviour" being used.
This illustrates the major obstacle to the layman's understanding of cutting edge physics - the use of words which obfuscate rather than enlighten!
I'm still researching in a quest to put the latest ideas in spacetime theory into simpler words. It's helping me to get my head around it at least!
In the quantum world, a particle can be in two places at once. Only by making an observation do we force it to 'choose' its location.
Sabine Hossenfelder submits that the quantum picture is at odds with a smooth, continuous fabric of spacetime. She says that, unlike matter and energy, "a gravitational field cannot be in two places at once".
So physicists are seeking a marriage between the two rival camps - they're searching for a theory of quantum gravity.
One of the contenders is Loop Quantum Gravity (LQG). Instead of being a smooth, continous fabric, LQG says that spacetime has structure on the smallest scales - just like zooming in on a piece of cloth and seeing the individual stitches, or zooming in on an LCD display and seeing the individual pixels.
The trouble is that when LQG physicists say small, they mean really small. The structure of spacetime would only be apparent on the level of the Planck scale - around a trillionth of a trillionth of a trillionth of a metre.
How, then, can you detect spacetime structure that small? Read the rest from my reference source here: Was Einstein wrong? Why some astrophysicists are questioning the theory of space-time | Space
In the quantum world, a particle can be in two places at once. Only by making an observation do we force it to 'choose' its location.
Sabine Hossenfelder submits that the quantum picture is at odds with a smooth, continuous fabric of spacetime. She says that, unlike matter and energy, "a gravitational field cannot be in two places at once".
So physicists are seeking a marriage between the two rival camps - they're searching for a theory of quantum gravity.
One of the contenders is Loop Quantum Gravity (LQG). Instead of being a smooth, continous fabric, LQG says that spacetime has structure on the smallest scales - just like zooming in on a piece of cloth and seeing the individual stitches, or zooming in on an LCD display and seeing the individual pixels.
The trouble is that when LQG physicists say small, they mean really small. The structure of spacetime would only be apparent on the level of the Planck scale - around a trillionth of a trillionth of a trillionth of a metre.
How, then, can you detect spacetime structure that small? Read the rest from my reference source here: Was Einstein wrong? Why some astrophysicists are questioning the theory of space-time | Space
Physicists no longer consider that electrons move in set orbits. That idea has been superseded by the 'quantum model' of the atom where electrons are 'clouds of probability' and their position is uncertain.
Perhaps you could look up the estimated diameter of a hydrogen atom, compare that with the Planck scale quantified above and tell us what you come up with.
Perhaps you could look up the estimated diameter of a hydrogen atom, compare that with the Planck scale quantified above and tell us what you come up with.
Far too much damn probability in all this quantum stuff. I prefer things that are pinned down. Exact. Precise. Observable.
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