Gravity and expansion

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Jan 29, 2020
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As I reason, this is about the boundary between an atom and vacuum energy. If it is about future dark energy's effects in the atom, I can Scholar it. I'd guess the interaction gets shoved to the perimeter and this happens as about the middle most forcing (from Quora):
"Romeel Davé
Astronomer, astrophysicist, cosmologistAuthor has 3.5K answers and 6.2M answer views3y...
You misunderstand what dark energy is. It’s a common misunderstanding owing to the name, but it is not energy in the sense of E=mc2E=mc2, which (together with the Uncertainty Principle) is where virtual particles come from. It’s really more appropriate to call it a vacuum pressure, but that doesn’t sound as sexy.
Dark energy generates a repulsive force, like a pressure. Virtual particles create (for a very short time) matter that generates an attractive force. So it does exactly the opposite of what dark energy does."

It may be more about pairs, but it works for single atoms too. The opposite works too. Matter is created at early super-inflation, and lost in the distant future. At some future dark energy increased vacuum pressure, the atom will disappear. Probably a 1/2 dozen quantum foam effects happen before dark energy overcomes the cohesion of other QED forces within the atom. Fast enough dark energy acceleration changes might rip the atom into leptons or something in the past.
 
Would we know if we were expanding in space?

I have been thinking about how space itself behaves in the vicinity of black holes and during the Big Bang, and am wondering if we can test our theories about it.

As a thought experiment, I consider a cubic box that is 10 meters on a side, so it contains 1000 cubic meters of “space”. In that box is a one kilogram mass moving in a straight line at 1 meter per second.

Now, let’s think about being able to watch that box shrink by a factor of ½ in linear dimensions with a person inside that also shrinks by the same factor, while we stand outside and are not affected by the shrinkage. Now, the person inside has a meter stick that is ½ what it used to be, so he still measures the box to be 10 x 10 x10 meters. But, what does he think about the kinetic energy of that moving mass? Assuming that energy is conserved even when space shrinks, that kilogram mass would now seem to be moving at 2 meters per second to the person inside the box, IF his seconds are the same as ours outside the box, where space has not shrunk. That would be an apparent increase in kinetic energy by a factor of 4. However, what if the measure of time inside the box also shrinks by the same linear factor as the physical dimensions of the box? Then, the observer inside would see the speed as ½ the distance over ½ the time, so apparent velocity would be unchanged and the kinetic energy would appear to be unchanged to the person inside the shrinking environment, just like it appears to be unchanged to us observers outside the box in “stable” space. However, those of us outside would now say that the energy density in that shrunken part of space has increased by a factor of 8, because the same energy is in one eighth of the original volume. But, the shrunken observer inside the box would think that the energy density has not changed. So, scaling time along with physical dimensions would make a shrinking or expanding observer unable to determine that he is shrinking or expanding IF that is the way it works.

I don’t know what to think about how this might play out in the Big Bag time line. That sudden inflation by more than the speed of light seems really odd to me. But, if time is scaled along with the size of the universe by the same factor, then (theoretical) “observers” inside the rapidly expanding universe might not know that it was rapidly expanding.

However, that conjecture about time seems opposite to the way that proximity to mass has been shown to affect the passage of time. Time really does run slower when the observer (or clock being checked later) is close to a large mass. So, I would expect a clock that is stuck in the middle of a tightly compacted mass of the entire universe to run extremely slowly in the initial tiny moments of the Big Bang. Now I am having a hard time wrapping my mind around what that should look like to an observer who is inside that compacted universe.

And, what type of observer are we now? "Looking back" at the Big Bang, it seems we are trying to be "outside the box" observers. But, our observations are actually made while we are still in that box, today. Can we really change our perspective by "looking back in time" with telescopes looking at very distant objects?

I admit that I am confused - and I wonder if those who propose theories like BBT are also confused, too.
 
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Catastrophe

"There never was a good war, or a bad peace."
Unc, there are a few comments I might make about the framing of your experiment, but, making a qualitative choice, I will stick to the very positive aspects:

So, scaling time along with physical dimensions would make a shrinking or expanding observer unable to determine that he is shrinking or expanding IF that is the way it works
My emphasis.

Can we really change our perspective by "looking back in time" with telescopes looking at very distant objects?
My emphasis.

I admit that I am confused - and I wonder if those who propose theories like BBT are also confused, too.
My emphasis.

I am addressing these in bulk, because they parallel closely the conclusions of:
Is the Big Bang in Crisis? By Dan Hooper Astronomy October 2020
namely,

We do not know how the particles that make up the atoms in our Universe managed to survive the first moments of the Big Bang, and we still know little about cosmic inflation, how it played out, or how it came to an end – This energy might have taken the form of an exotic species of light and feebly interacting particles, or of some kind of dark energy associated with the vacuum of space itself that has long disappeared from the Universe from the Universe. Or perhaps there is something else we don’t understand about this era of cosmic history.
My emphasis.

This energy might have taken the form of an exotic species of light and feebly interacting particles, or of some kind of dark energy associated with the vacuum of space itself that has long disappeared from the Universe. Or perhaps there is something else we don’t understand about this era of cosmic history.
My emphasis.

I have already mentioned several times, that some things might have been different then. I am pleased that I now have some agreement.


Cat :)

Goodbye and Good Riddance to this being over exaggerated:

Uniformitarianism, also known as the Doctrine of Uniformity or the Uniformitarian Principle, is the assumption that the same natural laws and processes that operate in our present-day scientific observations have always operated in the universe in the past and apply everywhere in the universe.
Uniformitarianism - Wikipedia
 
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Catastrophe

"There never was a good war, or a bad peace."
Unc, with regard to the ideas in your post #28, to which I gave a 'like', there are some interesting concepts there.

However, I do find difficult, the assumption of a nearby observer of normal size looking in the small box, which contains a small human.
with a person inside that also shrinks by the same factor, while we stand outside and are not affected by the shrinkage
OK, I can imagine it, but I think that a scientist could well say that your assumptions belie the observations and thus devalue the conclusion - granted, always, that this is a thought experiment.

Also, we know, of course, that our rulers (measuring sticks) do not change with the expansion of space - as we also know, that would neutralise the expansion (units measured would remain the same)'

And, again, (sorry to be nit-picky), but
Assuming that energy is conserved even when space shrinks, that kilogram mass would now seem to be moving at 2 meters per second to the person inside the box
Can you assume that energy is conserved in this highly convoluted thought experiment? Does the person who is shrunk also retain the same mass?- i.e., increases in density? Sorry, but these are the consequences of your thought experiment. You have a really interesting idea there, and I am sorry to be a bit nit picking, but, for me, it is too convoluted to identify with any real situation. It may be my bad, but I cannot relate to the conclusions. I can, at a pinch, imagine the 'observers' to be wispy unreal beings, which can observe, but which don't change density when shrunk, but I cannot assume that a kg weight 'stays the same' as well.

I admit that I am confused - and I wonder if those who propose theories like BBT are also confused, too.
I am just as confused myself, and I suspect that those proposers might be so
confused as well. I am definitely with you on that.

Is there any way you can frame this in such a way as to be more scientifically acceptable?


Cat :)
 
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Cat,

Don't worry about being "nit picky", because I framed this thought experiment and posted it so that people would think about the details and pick at them. Some of those nit picks will also apply to other concepts, particularly the Big Bang Theory. I framed the thought experiment in way that specifically opens up the questions that you posted, because that is what I am trying to get people to think about and discuss.

I specifically chose a mechanical system that involves mass and kinetic energy because we have a more intrinsic common understanding of those than we do of "fields" and things with "dual natures" of both particles and waves. And, we can still compute pressures and temperatures with the physical model, although I did not go there, yet.

So, I am not sure what you think would be a better model for a thought experiment that examines the properties of "inflation" and asks if those involved in it would be able to perceive it happening, in either the expansion of contraction mode.

The first item I proposed for discussion in this thought experiment is whether the "inflation" of "space-time" occurs in just the 3 physical dimensions, or if it involves the 4th dimension, time, in the same manner as the other 3 dimensions. My tentative conclusion is that, if the measurement of time is scaled by the same factor as used for the measurement of the other 3 dimensions, then it would not be observable by those being "inflated" or "deflated", even though mass and energy are conserved, at least in this simple model test chamber, and with the assumption that all of "space" expands or contracts by the same amount, including the space in the room down through the space between subatomic particles in atoms.

So, it is still open for discussion on several fronts, including the assumptions I have already included and mentioned.

First, although we have good evidence that the measure of time passage does change with speed and proximity to mass in the present universe, we really don't know how it changes with "inflation". So, I don't think there is any reason to assume that "inflation" cannot alter time measurement. The real issue is in what manner(s) might it do that, and how would that change our perceptions and conclusions about the universe.

And, we also don't know whether "inflation" really does move physically constant-dimensioned masses farther apart in "space", rather than simply expanding both the physical measures of the dimensions of the masses and the spaces between them such that they maintain the same scale relationship, much like just zooming-in or -out on a view screen. That gets to your point about whether the meter sticks inside my thought experiment box would be invariant or shrink by 1/2. My opinion is that the meter sticks must inflate or deflate along with the space. But, the way that the BBT is presented, we seem to be thinking that the whole universe could be measured at much less than a "meter" just after the "Big Bang". My question to the theorists is "Whose meter?" And a similar question about time measurement, so that we can get "speed" estimates for "inflation".

What I am saying is that it seems to me that the currently written presentations of the BBT seem to assume exactly what you posted that you are having trouble imaging - being an "outside observer" to the universe as it undergoes the "Big Bang" initial event. It is your trouble with imagining that which is really my intended area to explore with this thought experiment.
 
Cat,

Additional thoughts about your initial comments on my thought experiment:

First, realize that I am only exploring a concept called "inflation" that was introduced by the theorists who are trying to figure out how the universe could have grown from something microscopically tiny to what we see today assuming that jt must have been smaller than the event horizon associated with its mass during its earliest history. They postulated "inflation" as something that can move space in a manner that defies the General Theory of Relativity so that dimensions can increase against otherwise overwhelming gravity and at speeds faster than the speed of light. They postulate that "inflation" is driven by "dark energy" that is, at this point, totally undetected and undefined.

They do seem to consider mass, or at least mass plus energy-equivalent mass, to be conserved in the BBT following its initiation. So, I am going with that in this thought experiments, so far, at least. But, I am open to other ideas.

So, what I am trying to do is explore the implications of those new concepts, not to prove or disprove anything. Too often, theorists are satisfied with proposing new things to solve theoretical problems, without exploring the further implications - and without proving the correctness of their new concepts.

If there really is such a thing as dark energy that can move space dimensions faster than light speed, it would be something that might allow humans to travel among the stars, if we can learn how to create and/or control it. So, something worth thinking about, even if not something we can really fully believe at this point in our actual knowledge base.
 
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Catastrophe

"There never was a good war, or a bad peace."
OK, but what about mass and/or density changes. Of course, endemic in your thought experiment.

May I say how thrilled I am at your logical destruction of these inertia-sagging assumptions?
Best attack them now, and start a new 'revolution' of thought.
For example, see 'Is the Big Bang in Crisis?' By Dan Hooper Astronomy October 2020

Cat :)
 
Remember, I am looking for things that would let shrinking (or expanding) observers detect the changes. That is complicated by so little definition of what "inflation" actually does. So, my thought experiment necessarily involves looking at a variety of assumptions about how inflation really works.

My first part of that variety was to consider whether time measurement is affected by inflation, or not. In that regard, I just now looked at what a pendulum clock would do in the half-sized cube after it shrank. If time measures shrank by the same factor as the physical size measures, which would make the previously discussed parameters of speed and kinetic energy look the same, I think that a pendulum clock would have a different graph for its tick rate compared to its pendulum length, because the square of the tick period is proportional to the pendulum length. So, reducing the pendulum length by 1/2 and reducing the time period measured as one second by 1/2 would end up making the relationship for the pendulum change by (1/2)^2 divided by1/2 = 1/2 of the undeflated correlation constant.

Even if a present day observer does eventually measure dimensional changes due to inflation, that still doesn't address the question of how time could progress when the mass is concentrated in a tiny volume, given General Relativity predictions (and verifying measurements) about how time changes more slowly in locations close to large masses. Since there can be no masses larger than "everything in the whole universe" and the proximity to that can't get any smaller than postulated for the moment after the Big Bang, I don't see now time could be passing with much speed in the early universe.

Regarding the possibility for changes in mass with inflation, I don't think theorists are currently assuming that mass (actually mass + energy equivalent mass) changes as the universe inflates to its present conditions once "mass" is "created" by the Higgs Field/Higgs Boson. At this stage of the thought process, I don't want to get into discussing the Higgs Field, so let's at least start with thinking about inflation/deflation of small factors around present conditions.

Getting back to my issue of whether time might be scaled by the same amount as physical dimensions. If mass does not change in a closed volume, but measurement of space changes, then densities would look the same, because there is still the same amount of mass in the same measured volume. That is, a 0.1 m x 0.1 m x 0,1 m volume of water would weigh 1 Kg, and, if it and the meter stick both shrank in physical dimensions, then it would still be the same mass in what looked like the same volume to a shrinking observer - so same density.

I do intend to look at effects on pressure and temperature parameters, but need to go do some other tasks before it gets dark here.
 
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Ok, let's discuss pressure, next.

Pressure would be the change in momentum at one of the cube's walls as mass impacts on it and bounces off (or maybe sticks - but let's do bounces, so the pressure is not changing with time). Let's say that the 1 kg of mass is a bunch of marbles moving at 1 m/sec, and that they are perfectly elastic, so momentum is reversed when they bounce off the walls. Because the observers who "deflated" by 1/2 could not see the change in velocity or the measurement of surface area if the time measure also deflates by 1/2 then they and the not-deflated observers outside would compute the same amount of momentum impacting the same size walls, each with their own measurements for wall size and marble speed. So, under the assumption that time scales with physical dimensions, measuring momentum would not be an inflation detection method.

I will start on a discussion of temperature, but it is much more difficult, and I will not get "finished" in this post or maybe ever.

The problem is that I am not clear that measurements of temperature is necessarily only the kinetic energy of the particles in the medium. Energy additions to some materials don't all go to particle kinetic energy in the (x,y.z) dimensions. For complex particles, some energy goes into internal structures, such as vibrations of atoms, energy level of electrons, etc. There is even a difference in the amount of energy that needs to be added to raise the temperature by one degree when a gaseous material is kept at the same volume while the energy is added, compared to letting it expand while maintaining the same pressure. And, there are the energy values needed for phase changes, such as the heat of condensation/evaporation to change between gas and liquid, and the different value to change between liquid and solid, and another between solid and gas - not to mention ionization. And, when we get into things like quark plasmas and the even more esoteric soups of even smaller sub-atomic particles, I am not even sure how they compute a "temperature". I suppose it has a basis in the amount of energy needed for the colliding protons and antiprotons to "make" certain particles in the CERN atom smasher. Which seems to need some additional assumptions to turn a dynamic condition into a static condition measurement.

And, how we actually measure "temperature" is also quite varied. Sometimes it is the change in volume of a liquid like mercury or alcohol with red dye in it. Sometimes it is computed on the basis of emitted radiation spectrum, based on wavelength measurements of light emitted from a "black body".

How all of those temperature measurement techniques would be changed by deflation of, say 50%, or inflation by 100%, is not something I can fully envision at this point. Anybody else have some thoughts on perceivable effects of inflation on temperature measurements?
 

Catastrophe

"There never was a good war, or a bad peace."
"Time" does not work. Who measures time with pendulum clocks? Time will not change, only some means of measurement. If all the observers had digital watches they would read the same. Also, if you are talking about one tiny man in a box, he will not change the Solar System. Days, months, years will not be changed, so neither will minutes or seconds.

So that will affect your argument on pressure. If you consider the change in volume occurring slowly, then the velocity does not change, but the walls get closer, so impacts are more frequent, and pressure increases. I think, as with time, length does not change, only the measurement of it. Coming back to the Solar System, the AU does not change, or the Earth Moon distance. There are just more "box widths" in these distances. Coming back to your ruler (measuring stick), if Earth is anything to go by, things within Earth's gravity (for practical purposes) do not change - as for the reason you have given. We would be unaware of expansion/contraction.

When it comes to pressure, you have assumed that you can change a 1 kg weight for a 'bunch of marbles'. Would you not need smaller entities than marbles to change pressure.

When you start discussing relativity, are not the times and distances too similar to Earth measures? Your marbles are not travelling close to c are they? Ditto consideration of inflation. Isn't this "one man and his dog in a box" approach getting carried a little too far? You know what I mean, by the old song "One man and his dog went to mow a meadow"?

I am also a little unclear about temperature. are you going to start applying a Carnot Cycle? Are the conditions in the box appropriate? Are you going to kill off the observers in the box with pressure or temperature? Are the conditions/assumptions getting a little too fanciful to mean anything at all? Just asking a few questions. :)
 
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Cat,

I seem to be losing you as far as following the thought experiment I am trying to use.

You have posted several statements as if they are facts, but there is not proof that they are facts.

Specifically, there is no poof that inflation did not and is not still changing the dimensions of things in our galaxy, our solar system and even here on Earth's surface. If it is changing the distances between galaxies and between stars within galaxies, why not between the ends of a meter stick? My question is about how to prove that one way or the other. Simply stating that it must be one way, without proof, is not scientific method.

And there is no proof that time does not change with inflation. In fact, General Relativity Theory would seem to indicate that time will change at points that get closer to or farther from large concentrations of mass. So, even if time is not changed directly by inflation, it seems likely that it would change due to the indirect effect of changes in proximity to mass as mass is spread out further in the expanding universe. We need to stop assuming that time is passing at a constant rate everywhere at all times. Having inflation change the measure of time (think a "clock tick"), at the same rate that it changes the measures of the physical dimensions is perfectly in keeping with the idea that space is a 4-dimensional thing, (x.y,z,ct). But, being "consistent with a concept" is not the same as proof that it is true. Hence, my use of the word "if" when describing the speculative consequences of that tentative assumption being used in some of the thought experiments.

Regarding "Who measures time with pendulum clocks? ": It really doesn't matter that they really are still in use today. (I actually have one). The point is that it is a fundamental physical phenomenon for a "clock tick" that can be shown to differ between two states that have experienced different amounts of inflation, even when using the test assumption that time scales linearly by the same scalar quantity as the physical dimensions during inflation. That is the type of thing I was hoping to find. So, I posted that I have found one way that the assumption might be tested in a quantitative manner.

Your comment about pressure changing as the walls in my thought experiment test cube get closer from a factor of 2 deflation is also missing the point about how that would be measured inside the cube by observers who themselves have also shrunk by the same factor and had their time increment measuring system as well as their meter stick shrunk along with their room. Please look again at the math involved, and I think you will have to agree that the pressure measured by observers inside the cube will look the same before and after the cube is "deflated" by a factor of 0.5 if you assume the things that I have specified for this thought experiment. It does not matter if you believe those test assumptions - what matters is the logic and the math that relate the assumptions to the results if the assumptions are correct. And, results seem to indicate that a pendulum clock would not scale the "clock ticks" in the same manner as assumed for the time increment measurements. So, that would provide a way to test the assumption about the scaling of time (at least if we could find 2 places in space that have experienced different amounts of inflation or one place where inflation is still fast enough to measure with means within human capabilities).

I will do "temperature" in the next post.
 
Discussing the effects of "inflation" on the measurement of temperature seems too hard to corral into a simple physics kinetic discussion. So, I want to step away from the 10 meter cubic box used in the previous thought experiments and instead use the cosmic microwave background radiation to think about some potentially relevant factors. That has the advantage of being a real phenomena with actual observations that don't have to be imagined. But, the interpretation of that phenomenon has involved a lot of imagination. So, my process is to try to look for alternative assumptions, see what differences they would make in conclusions, and then see if those assumptions can be tested.

As I understand the theory for the inflation of the universe to have resulted in the background microwaves, the whole universe was filled with what is basically hydrogen plasma - protons and free electrons. Expansion of space itself let the plasma expand and thus cool, until it reached a point where hydrogen atoms formed by the protons capturing electrons into quantum state orbitals, making neutral hydrogen atoms, which cannot absorb photons below a certain energy value that exceeds the energy needed to strip electrons from their proton nuclei. So, once electrons became bound to protons to make electrically neutral atoms of hydrogen, the photon radiation already being emitted and reabsorbed in the universe was able to travel without being absorbed. That radiation spectrum is thought to represent a black body temperature of about 3,000 K. A factor of 1090 of additional expansion of space since that point in time about 13.4 billion years ago is thought to have stretched the wave length of the photons traveling through it, so that the resultant wave length match the black body radiation spectrum of the temperature 2.725 K as we see that radiation, today.

Also, at that time, stars were not yet thought to have formed.

Working from that, I have several questions.

First, why could stars not have formed while the universe was filled with hydrogen plasma, since that is what the earliest stars were made of to begin with. Plasma has mass, and mass concentrations create stars when they collapse and make the hydrogen plasma dense enough and hot enough to fuse into helium plasma. How do we know that plasma concentrations that were starting from an average that is 1090 times what it is today and would obviously have had variations in density could not have developed some stars doing fusion while the universe was still opaque to photons?

Second, what is the ionization energy: I found this: "[h]ydrogen is present almost entirely in the form of neutral hydrogen (H I) for temperatures below about 7000 K, but above that temperature there is a rapid transition so that above about 10,000 K the hydrogen is present almost completely as ionized hydrogen (H II). In the region 7000 - 10,000 K the gas is a mixture of H I and H II." See http://csep10.phys.utk.edu/OJTA2dev/ojta/c2c/ordinary_stars/harvard/ionization_tl.html .

How does the CBR temperature of 3000K fit this picture for hydrogen ionization as measured in our part of the universe at our current time? Does the BBT make some adjustments for hydrogen ionization energy due to differences in hydrogen atoms' electron energy states as a function of the amount of inflation those atoms have experienced? I have not heard of that, but it seems like a valid question to think about. If inflation is indeed expanding everything, including atoms, then it is logical to ask if that would change the measured properties of those atoms.

That is all I have time for right now. It would be helpful if somebody with more familiarity with the assumptions and the resulting calculations used in the BBT would address the 2 questions that I have just posted.
 

Catastrophe

"There never was a good war, or a bad peace."
Can I clear one question, before I try to proceed?

Can the person(s) in the little box see out around the external world? For example, Sun, Moon, street lights, 'everyday' things in the 'big' world?

Cat :)
 
Cat, Not is my thought experiment. The box is just to make a small enough part of the universe to do some simple calculations, without worrying about the edge somewhere approaching infinity. The idea of the observers outside the box is just that they get to see both the original and deflated conditions, so that they can compare them, while the observers inside the box can only see the current conditions, but could have some memory of past conditions, such as how the graph for the rate of a pendulum used to look before the deflation changed their measurements.

Reality would be more like the inflated/deflated observers are looking back in time as they look out into the universe, but would only be able to directly measure things in their own tiny region of space/time. So, maybe the things they are looking at very far away and very long ago happened with different conditions than what we can measure here. The theorized difference is a factor of 1090 expansion between the cosmic background radiation conditions and what is here, now. So, the issue is what could be different in the way of time passage or the physical parameters of matter such as energy levels of electrons in atoms when the space in them is 1090 times smaller than it is here where we are measuring those properties, now.

BTW, remember that the "axions" discussed in the paper I added with my P.S. are somebody else's thought experiment, not particles that have been detected and proven to exist. Like what I am trying to do here is a "what if", and so is that paper. There seems to be a lot of not-so-clear things going on in the discussions of the CBR, which is where observation transitions to nothing but theory in the BBT time line.
 
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Catastrophe

"There never was a good war, or a bad peace."
unc,
A box 10 x 10 x 10 metres is not going to give problems of approaching infinity, if the inhabitants can just see whether it is night or day, or what the weather is like. Anyway, you are saying they just have no windows at all?

Cat :)
 

Catastrophe

"There never was a good war, or a bad peace."
What I am trying to get at is, does this small world (box) have any sort of reality, or is it some totally impossible assumption without any connection with reality.

I cannot see any merit in inventing some totally impossible situation to 'prove' that 'reality' is not 'real'.

Sorry, I just do not understand what this is meant to signify.

Cat :)
 
I am not understanding your problem with "the box". So, how about you not thinking about the box at all. Just ask yourself if an observer in the universe would be able to tell the difference between 2 states of the universe, one that is "inflated" or "deflated" compared to the other. Consider the whole universe to be changed between the two conditions, not just the inside of a box.

The point of this thought experiment is to see if they can determine that the dimensions of space have changed between the 2 different conditions of inflation, with an underlying assumption that their meter stick and their clock have both been changed by the same amount between the 2 conditions. That is (x2,y2,z2,ct2) = 1/2 of (x1,y1,z1,ct1). Assume that mass is not changed, but the mass that fits within a specific amount of physical space as measured by a meter stick in the #1 condition will fit into the same amount of space as measured by the shrunken meter stick in condition #2. That is saying that the space within the mass has shrunk by the same amount as the space that is not in the mass. So, an observer that somehow is outside the inflation/deflation would see the density increase by a factor of 8 by still using their unchanged meter stick, but, because the observers who are getting inflated/deflated along with their meter stick (and clock) would measure the density as being unchanged by the inflation/deflation.

One you get that, you can look at how the hypothetical change in the clock rate associated with the inflation/deflation would affect measurements involving speed.

There is no need for any relativistic levels of speed to be considered in this thought experiment. This is not about the appearance of time change between 2 inertial frames of reference that are moving relative to each other at a speed that is a large fraction of c. Nor is it about the change in time passage rate that occurs in strong gravitational fields. Those two effects are independent and additive, as we have already discussed being demonstrated by our GPS satellite clock correction factors. This thought experiment is intended to consider what the effects would be if time is affected by inflation (independent of speed or gravity) in the same manner that spatial dimensions are affected by inflation.

Since you seem to want to think in terms of the whole universe, or at least the part we can observe, you could consider the actual observations of distant galaxies and even the CBR, but be careful to consider only the actual observations, without pulling in the assumptions from the BBT. So, we really do not know the age or origin of the CBR, we just know that it is everywhere around us, and can tell its frequency/energy level as we see it here and now.

Then, when trying to consider how the CBR came about, ask yourself how we would know if the physical properties of hydrogen that existed when and where the BBT assumes the CBR was produced were different from the physical properties of hydrogen that we can measure here on Earth or maybe in our own solar system, today. For instance, how could we tell if the temperature at which hydrogen plasma reassociates into neutral atoms is the same when space was less inflated by a factor of 1090 (or any other factor) compared to what it is here and now? Does inflation affect the ionization energy for hydrogen, maybe by changing the dimensions of the electron orbitals so that their quantum state energies are different?

I am asking this question because there does seem to be some difference between the assumption in the BBT that hydrogen reassociated in the distant past when the universe's plasma temperature cooled to 3000 K, compared to data from the sun that says the amount of hydrogen ionized is almost none below 7000 K and almost all above about 10,000 K. There is an estimated factor of 1090 for the difference in the amount of "inflation" between those 2 points in time that are estimated to be 13.4 billion years apart. I am wondering how to make sense of that, and whether the way the BBT did it is the only way that makes any sense.
 

Catastrophe

"There never was a good war, or a bad peace."
Unc . . .
I am not understanding your problem with "the box". So, how about you not thinking about the box at all. Just ask yourself if an observer in the universe would be able to tell the difference between 2 states of the universe, one that is "inflated" or "deflated" compared to the other. Consider the whole universe to be changed between the two conditions, not just the inside of a box.
Why didn't you say that in the first place?

I think it was the box's problem with the box? That simply required me to define the properties of the box, to try to understand why you put it there in the first place. ;) ;) ;)

Cat :) :) :)
 

Catastrophe

"There never was a good war, or a bad peace."
Unc, I still have difficulty in seeing what you are getting at.

Specifically, there is no poof that inflation did not and is not still changing the dimensions of things in our galaxy, our solar system and even here on Earth's surface.
I think we agree, for a start, that if everything, including measuring sticks were expanding, then we would not notice the expansion. That is not in question, I believe?

Are you suggesting some differential expansion? Some things expanding, but not others? I am afraid that that would give me a very bad headache. You have been kind enough to post reams, which I appreciate, but rather than keep reading it through, can we please just take it easy, and deal with one point at a time?

Cat :)
 
OK, I'll try to make it simple:

I am trying to explore the assumption that there was and still is "inflation" of space. "Inflation" is not defined in detail by the theorists, and there is disagreement whether it increases the size of everything in the universe as it increases the size of the universe itself (at greater than the speed of light, but not at a constant rate). So, necessarily, I am asking questions from some different, and sometimes incompatible perspectives, to see what the implications are for more detailed specifications for "inflation" and whether we have a means for testing whether some of those details are true or not.

So, I am not trying to specify a particular set of assumptions as being "true", and that may be leading to some confusion, because just about everybody else who posts here seems to have a set of beliefs that they argue in favor of. What I have posted so far is more in the nature of "if-then" for several alternatives.

The main thrusts of my posts are to question how "inflation" can do what the BBT needs while not doing other things that undermine what the BBT assumes to be invariant.

So, I am asking if time passage, or at least measurement of time passage, also changes with the physical dimensions as "space-time" is "inflated".

And I am asking if the dimensions of atoms and/or molecules change with inflation, and if that changes the energy levels of electron orbitals, and if that changes the assumptions about at what temperature hydrogen atoms condense from hydrogen plasma. All of those things might alter how we compute the amount of expansion and the timing of the expansion that we are inferring from the cosmic background radiation.

I am not saying that I have the answers for these questions - I am suggesting them for thought and discussions by others.
 

Catastrophe

"There never was a good war, or a bad peace."
I am trying to explore the assumption that there was and still is "inflation" of space. "Inflation" is not defined in detail by the theorists, and there is disagreement whether it increases the size of everything in the universe as it increases the size of the universe itself (at greater than the speed of light, but not at a constant rate).
I am bemused at the so called gravitational effect which acts against expansion, so that we don't expand - only the spacetime around us. Doesn't this cause a problem when the two meet - expanding space and non-expanding space? I.E. The bits around objects?

Cat :)
 
Cat, I think at least some of the people who think that our bodies, metersticks, maybe our solar system and maybe even our galaxy are not expanding like the rest of the universe are saying that the expansion is not happening because other forces are making those pieces of matter move through space faster than the space is expanding, so that those things retain their same dimensions under the control of stronger sets of attractive and repulsive forces.

So, there would be no hard edge effects where expanding space meets space that doesn't expand. All space expands, but matter's distribution in that space is controlled by forces that maintain that matter's shape and size by moving its edges through space more rapidly than space expanding can change those dimensions.

I just say "Maybe so, maybe not."

My problem is trying to understand what "space" is and how the "fields" that are hypothesized to "fill all of space" actually relate to each other and to "space" itself. Worse, some theorize that all of matter is just waves in those fields of various types. Even "mass" is supposed to be created by the "Higgs Field" and its ripple waves.

So, how do we envision all of these "fields" responding to "inflation". We seem to believe that light travels through the electric field that fills space and is stretched by the expansion of space so that it is red shifted by "inflation". To me, that indicates that "fields" and the ripples in them that are the photons, electrons, quarks, etc. should stretch as space stretches.

So, my best guess is that the physical dimensions of objects of all sizes change by the same factor as "space" as it is "inflated", because we see light being stretched and are attributing that (mostly) to "inflation" of the space that the light is in.

But, these imagined "fields" are not all postulated to have the same properties. The "Higgs Field" is being called "sticky", whatever that really means.

It would be helpful if somebody could explain how fields for the different forces (gravity, electromagnetic, strong nuclear force, weak nuclear force and Higgs) are related and interact. There clearly needs to be some sort of interaction, or the properties like charge and mass would not be able to stay associated with the same "particle" if these different parameters/properties are just independent "waves" in independent "fields".

And, then, I want to know how these theorists think those fields respond to "inflation". Some of their hypotheses seem inconsistent to me. But, I am willing to listen to answers to my questions with an open mind.
 

Catastrophe

"There never was a good war, or a bad peace."
I think at least some of the people who think . . .
Certainly many people think lots of different !ideas".

I just say "Maybe so, maybe not."
Agreed. But they are not of equal scientific probability.

the "fields" that are hypothesized to "fill all of space" actually relate to each other and to "space" itself.
Are we back to Michelson Morley?

It would be helpful if somebody could explain how fields for the different forces (gravity, electromagnetic, strong nuclear force, weak nuclear force and Higgs) are related and interact.
I certainly agree about that. Back to Universal . . . . . .

And, then, I want to know how these theorists think those fields respond to "inflation". Some of their hypotheses seem inconsistent to me. But, I am willing to listen to answers to my questions with an open mind.
Me too, or should it be I also?

Cat :)
 

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