[SOLVED] Hypothetical question about gravity

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Faust

Re: [SOLVED] Hypothetical question about gravity

Post by Faust »

What is the universe expanding into ?
Nothing , that's what . It's not as if there is more ( spare ) space , outside of it .
Gravity "tells" space how to curve .

These would seem to cover all of the options :-
The universe is either bounded / unbounded , and finite / infinite ( plus some possible combinations ? )
That's from " Brief History of Time " , so I'm not going to nit-pick .

And then there is the " Anthropic Principle " which states that the universe is the way we observe it to be ,
because if it were different in any significant degree , we would not exist to make the observations !

Pretty heuristic reasoning IMO , but there are some smart cookies who hold to it .

What are you going to do ?
Build a machine that changes the gravitational constant ? ..... or annihilates all Higgs Bosons ?
It's not easy to put these things to the test - :lol:

Just my two kopiykas worth ....
..... some random thoughts on this topic , which strangely appears to be marked as "solved " !

:mrgreen: :mrgreen:
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Re: [SOLVED] Hypothetical question about gravity

Post by Fred Barclay »

Oof! Yeah, sorry to have offended you, catweazel.
As for the "playing dress-up physicist"... you're free to draw your own conclusions. I've said repeatedly that I'm a radiation physicist, not a cosmologist. It's no surprise that I'm a bit behind on the latest ideas -- I don't normally have to worry about anything smaller than electrons or larger than linear accelerators.
Since you seem so interested in me all of a sudden, I would have gladly posted my ORCID so you could review a list of my publications and etc and verified the complete lack of dress-up going on, but that would personally identify me. "Fred Barclay" must remain anonymous!

Your definition of "physicist" is surprising and limited only to, what, astrophysicists and cosmologists? I presume at that rate you'd propose that Einstein (who hated the probabilies inherent to the Copenhagen interpretation of quantum physics) was no physicist either? Michael Faraday -- whom, as I'm sure your aware, had a lot to do with field-only theories -- must not have been a physicist too. Nor either of the Curies (also chemists), Roentgen, Lord Kelvin,... I'm sure you get the idea. None of these chaps were cosmologists, and the only one of them who actually learnt of quantum mechanics was violently opposed to large portions of it, yet all were physicists. Fortunately, your seeming definition of who qualifies is too narrow. Else I'd have to change my job title and advise my institution they've hired me, and the rest of the department, in the wrong position!

Also, some of the above folks were religious too -- but your thought seems to be that religion imminently disqualifies folks from serious science. In that case, we need to throw out the concept of 0 (from Hindus and the Mayans), algebra (Muslims mathematicians), fields (Faraday was a devout Christian), and calculus (Leibnitz and Newton were Lutheran and Anglican, respectively). Heisenberg and Einstein were somewhat religious as well. Of course the opposite is true as well -- Hawking was, IMHO, one of the most brilliant mathematicians and physicists we'll see in a long time, and also seems to have been a firm atheist. I do not want to start a religious debate here, but I do take issue with your assertion.
catweazel wrote:...the application of a label necessarily entails the existence...
Ok, then. I will label the concept of a 13-legged, cream-coloured giraffe made entirely of glucose as "flautwurst." You must agree that flautwurst exist, right? I've just labeled it/them.
Or... you can agree that a concept or a label does not imply existence. I quite agree with you that nothingness, as the absence of anything (even signals), does not exist. That doesn't mean I can't conceive the notion and even describe what it would be like. I can even "coherently define" it -- nothing would be the absence of everthing (particles, waves, information...).

If you would prefer to use the quantum electric vacuum state as your definition of "nothing", then your conclusions may be correct. Though it also smells of the old steady-state cosmology that was discarded a while back, or Aristotle's whole "nature abhors a vacuum" idea.
Oddly enough, there are no particles
Possibly not. That's a single study from 2012 which hasn't yet had any impact on my, ahem, field ;) and this is the first I'm hearing of it. I see no reason to toss out wave-particle duality just yet -- it's a useful model. Besides, that paper is limited to a very particular bit of quantum physics. While I have no issue with quantum physics, surely you're aware that many of these "greater minds" you reference do have an issue with some aspects. Meaning no offense, but lots of these folks are far brighter than me and possibly you as well. Why are you so dogmatic about a theory that they don't think is a good model in its current form?

https://arxiv.org/pdf/1301.1069.pdf gives a snapshot (as of 2013) of physicists' attitudes towards quantum mechanics. You'll notice it's a mixed bag. It's also a very small sample size. :(

Neither of you is arguing from a scientific base, but from... Newtonian or classical physics
That's funny. Last I recall (and it's been a while since my intro physics at uni so you'll have to remind me if I'm wrong), classical physics had no concepts of relativistic effect such as time dilation or basic quantum mechanics. The Rayleigh-Jeans catastrophe was, well, catastrophic. Yet all of these I've been saying are real phenomena. So I'm not arguing from Newtonian or classical physics. You were saying?

Lastly, why? Does my discussion with trytip et al really bother you so much you had to come up with all those metaphors? I will be keeping that tri-flippered seal reference for later use, though. :mrgreen:

Cheers!
Fred
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Re: [SOLVED] Hypothetical question about gravity

Post by lsemmens »

catweazel wrote: Tue Mar 19, 2019 3:02 am
Fred Barclay wrote: Mon Mar 18, 2019 8:00 pm
catweazel wrote: Mon Mar 18, 2019 3:22 am As for the weirdness, "nothing" is a very unstable state so the the production of "something" out of "nothing" is inevitable therefore it should not be a surprise that we find ourselves in something.
That I disagree with. "Nothing" has no matter, no energy, no entropy*... I don't agree that nothingness is unstable.

*I assume. It's not as if we can actually measure the entropy and etc of nothingness -- anything measurable, by definition, couldn't be nothing.
It pays to know how to do your research in case greater minds than your own don't accord, then to know to check your presuppositions and seek clarifications, where appropriate, before playing dress-up physicist. There is the theological, romantical, faeries-at-bottom-of-the-garden idea of nothing, which, without doubt you are referring to, is not known to exist, and, by definition, cannot possibly exist; then there is the scientific nothing; the nothing of quantum field theory, the quantum electrodynamic vacuum state.
The team of scientists headed by Professor Alfred Leitenstorfer has now shown how to manipulate the electric vacuum field and thus generate deviations from the ground state of empty space which can only be understood in the context of the quantum theory of light.

With these results, the researchers from the field of ultrafast phenomena and photonics build on their earlier findings, published in October 2015 in the scientific journal Science, where they have demonstrated direct detection of signals from pure nothingness.
https://phys.org/news/2017-01-quantum-v ... space.html

The "pure nothingness" referred to is the scientific nothingness.

The moment you apply a single label to your unscientific idea of nothing, it has become something, and that is so because the application of a label necessarily entails the existence of an attribute, which, by your very own definition, it cannot possibly possess. Helloooo? It follows then that you cannot coherently define what you mean by nothing so are doomed to forever dance around each other in never-ending illogical circles, like a pair of seals, each missing a flipper, trying to fight over a hapless sardine.

Neither of you is arguing from a scientific base, but from each of your own personal interpretations of 17th century old-wives tales, otherwise known as Newtonian or classical physics, which has been resoundingly discredited by modern science as nothing more than gross approximation at best, and nothing that even remotely approaches a description of reality. You seem to be trying to impress each other over who can commit the most egregious errors of rudimentary logic in two words or less or who can spout boundless unscientific piffle and incoherent poppycock better than the other.

Nothingness is the absence of physical particles.

Oddly enough, there are no particles.

https://arxiv.org/pdf/1204.4616.pdf

It follows then that nothing exists. BOOM! BOOM!
And all that from an exile from 1066 - Before Newton even existed!!!!!! :lol: :lol: :lol: :lol:
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Re: [SOLVED] Hypothetical question about gravity

Post by catweazel »

trytip wrote: Tue Mar 19, 2019 9:38 am we're just having fun,
lol - and I wasn't?
"There is, ultimately, only one truth -- cogito, ergo sum -- everything else is an assumption." - Me, my swansong.
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Re: [SOLVED] Hypothetical question about gravity

Post by catweazel »

Faust wrote: Tue Mar 19, 2019 11:14 am What is the universe expanding into ?
Nothing , that's what .
Not according to a number of brane cosmologies. It is proposed to be expanding into what is called 'the bulk'.
"There is, ultimately, only one truth -- cogito, ergo sum -- everything else is an assumption." - Me, my swansong.
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Re: [SOLVED] Hypothetical question about gravity

Post by catweazel »

Fred Barclay wrote: Tue Mar 19, 2019 8:02 pm Since you seem so interested in me all of a sudden,
Wow! Talk about having tickets on yourself. I'll leave you to it.

Postscript:
Does my discussion with trytip et al really bother you so much you had to come up with all those metaphors?
It doesn't bother me in the slightest. I enjoy a good laugh, and I get immense pleasure out of metaphor :)
"There is, ultimately, only one truth -- cogito, ergo sum -- everything else is an assumption." - Me, my swansong.
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Re: [SOLVED] Hypothetical question about gravity

Post by trytip »

Faust wrote: Tue Mar 19, 2019 11:14 am What is the universe expanding into ?
does it really matter now that IT already is? so it expands to the "ends of the universe". will it go further or is there a limit? if there's a limit then there's something containing it. does something contain the container?
And then there is the " Anthropic Principle " which states that the universe is the way we observe it to be ,
because if it were different in any significant degree , we would not exist to make the observations !
if a tree falls in the forest does it make a sound? sure it does? there are other observers out there besides humans. does the universe experience Double Slit Experiment if an amoeba is observing?
Dr Quantum - Double Slit Experiment :) ok, you may ovelook the animation and the audience intended for.

why must human factor be included into all of this? we at the present are not observing the beginning of everything so why is it that we as intelligent humans have to put a "title" on something as if we are at the center of the universe? i seem to recall some other person saying that the Earth wasn't the center of the universe and his theories turned out to be quite factual even though it seemed as heresy.

but is the universe square or is it round? does it expand in spherical, elliptical or linear ways ? (ok gravity can join in on this one)

and what about infinite? is the universe infinite? how far is too far for you until you can't comprehend it. all of this they say came from a something quantum hole? people are so obsessed with the quantum stuff, they forget that to a universe as a "whole being" a quantum tear might just as well be a pimple being popped
Last edited by trytip on Wed Mar 20, 2019 9:14 am, edited 1 time in total.
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Re: [SOLVED] Hypothetical question about gravity

Post by catweazel »

trytip wrote: Wed Mar 20, 2019 1:43 am
...does the universe experience Double Slit Experiment if an amoeba is observing?
The Copenhagen Interpretation of quantum mechanics would say yes, provided the amoeba has some form of consciousness. What is missing from the video description you linked to is the extrapolation of the meaning of the double-slit experiment to its ultimate implication. An implication that poses a dilemma for philosophers. It goes something like this:

If it is true that a conscious observer is required to collapse the wave function into a single, real event, what, then, observed the universe?

The point is, no matter how hard science tries, it cannot get away from a creation event. It's ok to say that the universe was caused by murmurs in the quantum foam, but as far as we are aware, these events require a conscious observer to collapse the wave function into an actual event, hence the dilemma. For some.
"There is, ultimately, only one truth -- cogito, ergo sum -- everything else is an assumption." - Me, my swansong.
stormryder

Re: [SOLVED] Hypothetical question about gravity

Post by stormryder »

Faust wrote: Tue Mar 19, 2019 11:14 am What is the universe expanding into
Spacetime.
The electromagnetic radiation needs something to propagate through.
That is why the conversation I was having with catweasel about consciousness is relevant.
You perceive the absence of matter as nothing, but is pain something?
Does a thing have to be a "material" thing?
Is time a thing?
Out there beyond the expansion does time cease to exist?
Right now I'm working on a time and materials contract so for me time is thing 1, material is thing 2. Dr Sues was a genius. Things can be extremely hard to control and the most powerful things aren't always material.
trytip wrote: Wed Mar 20, 2019 1:43 am It's ok to say that the universe was caused by murmurs in the quantum foam, but as far as we are aware, these events require a conscious observer to collapse the wave function into an actual event,
I just realized I've actually witnessed this even though I never really understood why it happened til now.
The old tube TVs are a perfect example of this. While you watch it the electrons bombarding the screen are in wave form, we observe the photons emitted by the florescent particles. When you turn it off some of the electrons remain in the vicinity of the glass.
We can observe the electrons by touching them so when your hand approaches the screen you feel the electrons that collapse on your side of the screen and see the photons emitted by the fluorescent particles that react to the electrons that collapse on the other side.
This indicates to me that there is a deep connection between consciousness and that which we perceive as material.

I really like Walter Lewin's lectures.
https://www.youtube.com/watch?v=El3g9Xt ... DhSjTJATPu
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Re: [SOLVED] Hypothetical question about gravity

Post by Fred Barclay »

catweazel wrote: Wed Mar 20, 2019 12:54 am
Wow! Talk about having tickets on yourself. I'll leave you to it.
Had to look up the "tickets on yourself" expression -- we don't often have that in my part of the world. Anyways, no, not in the slightest. Just putting a bit of backstory out there since someone was apparently concerned about "playing dress-up" and whatnot. I enjoyed your tales of watching explosions without hearing protection, and etc, without worrying about your motives for sharing. ;)
I enjoy a good laugh, and I get immense pleasure out of metaphor :)
Very well then! Keep 'em coming. :D

So now a serious question for you since you seem far more familiar with the Copenhagen interpretation and so on than I. As I recall the CI is quite fine with spontaneous creation events as long as they're balanced out almost immediately by destruction events -- i.e. total energy and mass in the Universe is still conserved. But wouldn't the beginning of the universe have been a sort of creation event without a corresponding immediate destruction? If so, why the lack of destruction? (Perhaps "annihilation" would be a better term but in my field, at least, that usually refers to collisions of electrons with positrons and of course doesn't result in complete destruction, just conversion of mass to energy.)

Cheers!
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Re: [SOLVED] Hypothetical question about gravity

Post by catweazel »

Fred Barclay wrote: Wed Mar 20, 2019 5:53 pm So now a serious question for you since you seem far more familiar with the Copenhagen interpretation and so on than I. As I recall the CI is quite fine with spontaneous creation events as long as they're balanced out almost immediately by destruction events -- i.e. total energy and mass in the Universe is still conserved. But wouldn't the beginning of the universe have been a sort of creation event without a corresponding immediate destruction? If so, why the lack of destruction? (Perhaps "annihilation" would be a better term but in my field, at least, that usually refers to collisions of electrons with positrons and of course doesn't result in complete destruction, just conversion of mass to energy.)
The CI attempts to give meaning to QM in terms of knowledge gained. Spontaneous creation events aren't a feature of CI, nor are the conservation laws, both of which are founded on scientific observation. Destruction is the wrong word to apply to virtual particles because destruction results in a release of energy. What they (virtual particles) do is appear in our 3-dimensional world then promptly disappear back into the dimension where they presumably came from (neutrinos apparently do this all the time), rather than destruct, but here in time we are dealing with an equilibrium state, not the conditions under which we can postulate that the universe came into being, where there was indeed much destruction, but that destruction was due to matter and anti-matter collisions, which, rather oddly, must have been unbalanced (not in equilibrium) in order to leave our universe the way we find it otherwise there would be no universe for us to find. We assume that at the moment the universe came into being, equal amounts of matter (in the form of plasma) and anti-matter (also in the form of plasma) were generated at moment 0, but some event or other thing that we don't yet understand caused there to be an excess of matter arising from the destruction or mutual annihilation.

So, to answer the question, "wouldn't the beginning of the universe have been a sort of creation event without a corresponding immediate destruction?", the answer is no, there was wholesale destruction but something, which we don't yet understand, caused an imbalance and left something instead of nothing.

There is no analogy from the above to collisions of electrons with positrons. You correctly refer to conversion of mass to energy in such collisions, but when a particle spontaneously appears, our 3 dimensional world has, in effect, borrowed energy from a hidden dimension. When the particle pops out of existence, the borrowed energy is paid back, thus equilibrium is maintained.

Cheers.
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Re: [SOLVED] Hypothetical question about gravity

Post by 1.618 »

trytip wrote: Wed Mar 20, 2019 1:43 am
if a tree falls in the forest does it make a sound? sure it does?
If a tree falls there would be no sound, vibrations would be created in the atmosphere that require an ear to convert the vibrations into electric signals for your brain to interpret as sound. :)
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Re: [SOLVED] Hypothetical question about gravity

Post by trytip »

1.618 wrote: Sun Apr 28, 2019 5:50 am If a tree falls there would be no sound, vibrations would be created in the atmosphere that require an ear to convert the vibrations into electric signals for your brain to interpret as sound. :)
you mean to say non-human beings such as animals don't have ears? if a massive explosion would occur, let's say from a Hiroshima like blast equal to 15,000 tons of TNT, there would be no sonic shock wave if no one was there to acknowledge it's existence?
human senses are not the center of the universe and despite popular misconceptions i'm quite certain there were a few sounds on this planet as it was being formed (and in the universe) before humans came into existence.
i'm guessing then that the same philosophy would apply to light? if there's a star in the sky that omits light and no one is there to see it, does it really shine?
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Re: [SOLVED] Hypothetical question about gravity

Post by Flemur »

"Does this then mean that my observations become real only when I observe an observer observing something as it happens? This is a horrible viewpoint. Do you seriously entertain the idea that without the observer there is no reality? Which observer? Any observer? Is a fly an observer? Is a star an observer? Was there no reality in the universe before 10^9 B.C. when life began? Or are you the observer? Then there is no reality to the world after you are dead? I know a number of otherwise respectable physicists who have bought life insurance." -- Feynman Lectures

Re: If "sound": If a man is alone in the forest and there are no women around, is he still wrong?
Please edit your original post title to include [SOLVED] if/when it is solved!
Your data and OS are backed up....right?
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Re: [SOLVED] Hypothetical question about gravity

Post by lsemmens »

Flemur wrote: Sun Apr 28, 2019 1:22 pm .....
Re: If "sound": If a man is alone in the forest and there are no women around, is he still wrong?
Of course he is, just ask ANY woman. :D
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