Why?

Because Time is not an objective phenomenon? In this I completely agree with Bergson.

Because Time is not an objective phenomenon? In this I completely agree with Bergson. — Hachem

Well, physics obviously speaks about physical time that can be measured by a light clock which is invariant regardless of frame of reference.

This is indeed different than the experience of time which philosophy talks about. Why do you conflate the two?

This is indeed different than the experience of time which philosophy talks about. Why do you conflate the two? — Agustino

I don't, Einstein does, and before him his teacher that invented it.

Imagine for a moment that everything that happens in the current world speeds up to twice the speed. Objective time, as measured by the light clock, will appear to be the same. That is certain.

But will subjective time appear to flow twice as fast? I think so.

But a materialist determinist like Einstein wouldn't necessarily agree because if everything speeds up, the processes in the brain, which according to them are responsible for our subjective experience of time also speed up. So relative to their new speed, we will perceive no change in our subjective experience of time. That would be the argument I would say.

I already know the argument, and it is the most ridiculous thing I have ever heard. Ask biologists.

I already know the argument, and it is the most ridiculous thing I have ever heard. Ask biologists. — Hachem

Why do you say that?

Time, even as objective phenomenon, is never neutral. When you make biological processes run at two times their normal speed, you are not effectuating an algebraic process, like multiply both the nominator and the denominator by the same number, and the original number will not change.
Biological, and certainly psychological processes are what they are because of their rhythm, change the rhythm, and you will make organs work two times harder, age two times faster, and emotions completely change from quite to frantic.

edit: the difference between I did it my way by Sinatra and the other guy, the dj?

Time, even as objective phenomenon, is never neutral. When you make biological processes run at two times their normal speed, your are not effectuating an algebraic process, like multiply both the nominator and the denominator by the same number, and the original number will not change.
Biological, and certainly psychological processes are what they are because of their rhythm, change the rhythm, and you will make organs work two times harder, age two times faster, and emotions completely change from quite to frantic. — Hachem

Yes, but if materialism were true (which is what we have to assume for their explanation to make sense), then your subjective experience of time flowing at such and such a rate is created by the correlation of the speed of movements in your brain with the speed of movements outside your brain. If both of them increase at twice the speed, your subjective experience will not perceive the increase.

assume further my dear sir.

So our entire assumption about the universe expanding is based on one interpretation of a bit of red in a telescope when there seems to be other interpretations for that bit of red? Nobody can tell me why my question can't be proved false? That's pretty cool, but it can't be right. We would need a whole new set of extrapolated physics for each scenario - it would be a physicists dream and too obvious to be overlooked.

I had a similar thought like this a while back, though I was thinking that the universe(s) are moving away from the original center but are on a sort of gravitational bungi cord and eventually the universe will be pulled back and collapse in on itself.
I have no knowledge of cosmology, this is simply a poetic possibility.

So our entire assumption about the universe expanding is based on one interpretation of a bit of red in a telescope when there seems to be other interpretations for that bit of red? — MikeL

As T Clark points out back at the start, if the red shift was just us moving towards some mythical centre, then we would also be approaching other galaxies, creating a blue shift. And even if they were moving faster ahead of us for some reason, the resulting red shift would not be as red as galaxies in the opposite direction.

Then if it was instead just our galaxy collapsing inwards, we would have collapsed long before now. And also all the other galaxies would look redshifted equally regardless of their distance. They would all appear to have the same velocity, not a velocity that appears to accelerate until it eventually goes super-luminal (faster that lightspeed) and so get swallowed up by a cosmic event horizon.

So there are a whole bunch of astronomical observations which are simplified best by believing that what we see is an expanding/cooling universe. And science says the best theory is the one that accounts for the most variety with the least explanatory effort. We have no good reason to doubt the expanding/cooling universe hypothesis.

There is not just one observation that demands the theory. The theory is the only one that makes sense of everything we so far observe.

Remember Olber's paradox. If the universe is infinite and wasn't expanding we would be blinded at night by the blaze of every star in the cosmos. Thank goodness for event horizons that means we only see a finite number of those stars and so can sleep in the dark.

Yes, it is nice to reimagine every physical claim from its other angle, tell the same story in reverse. That is what physics gives you - reversible stories that thus connect starting conditions to final conditions in a predictable way. But if you actually try to understand the physics backwards, then you will become prone to all kinds of metaphysical error.

So red-shifting was the big clue that forced the reach for a good explanation. But there were already other reasons, like Olber's paradox.

General relativity also created an issue of how the Universe could be stable, given that it either had to be gravitationally collapsing, or for some reason expanding. We could guess it wasn't collapsing because otherwise our odds of being here to witness its existence would be infinitesimal (given infinite time, at any particular moment, collapse would have already occured with matching probability). So that only left expansion as the reasonable guess.

And now - surprise - Einstein was righter than he knew on that score. We have discovered a further observation, what has been dubbed dark energy or the cosmological constant, which tells us metric expansion is wired into the fabric of being. Expansion forever is a hardwired-looking fact now.

So as I say, physics ain't dumb. The expanding Big Bang universe was predicted by theory as much as it was necessitated by multiple lines of observation. Once Einstein cracked GR, expansion had to be the case somehow.

[Scratches arse and reaches for tin foil hat....] — apokrisis

I personally have no problem with the idea of a universe expanding. After all, it is as reassuring or scary as the idea of a finite world. A little like being afraid to reach the end of the earth and then fall off in the emptiness.

What we are talking about is the ontological value of cosmology. You are convinced of the veracity of the whole story, while others in this discussion are not. Again, I could buy into the idea of an expanding universe. What I do not buy in are the current cosmological theories.

You are convinced of the veracity of the whole story, while others in this discussion are not. Again, I could buy into the idea of an expanding universe. What I do not buy in are the current cosmological theories. — Hachem

I was explaining why cosmologists, as a pragmatic community of inquiry, would proclaim themselves convinced.

You are free to dissent. But your dissent only counts as reasonable if you can show you understand what is being said, and why, then make some other case in that light.

Otherwise its all fake news and alternative facts, as they say.

Please read the previous posts. You barge in and expect us to start all over again. That is not reasonable.

I have zero expectations of making any real difference here. That's way I might at least one day be pleasantly surprised. So carry on....

Thank you. But I was just about done. This was a side-street I was walking, with no real definite end to it.

I have, in another forum, spent as much time and energy that I could, based on my non-physicist background. And metaphysical debates have the annoying property of having no end. There are no knock out arguments for me to hit you with, and I do not think you have any in your possession either.

But it's all right, such an open ending is exactly what makes science interesting as far as I am concerned. What worries me is the theological devotion of people who call themselves scientists or materialists. BTW, I am old-fashioned, and for me materialism has more of a socio-political connotation than a metaphysical one. I have always felt closer to Marx than to Engels.

I find metaphysical materialism as is known in, among other places, American universities, as simplistic as Engels' attempts at philosophy.

As T Clark points out back at the start, if the red shift was just us moving towards some mythical centre, then we would also be approaching other galaxies, creating a blue shift. And even if they were moving faster ahead of us for some reason, the resulting red shift would not be as red as galaxies in the opposite direction. — apokrisis

Can't talk long as I'm at work. The resultant red shift intensity would be relative to the speeds of objects. It could be that they are both red shifted equally, one is blue one is red, or one is more red shifted than the other, surely.

If the entire galaxy was not collapsing, but rather shrinking (space shrinkage), the we could observe the red shift.

Sorry for the brevity. Do you get what I'm saying?

The resultant red shift intensity would be relative to the speeds of objects. It could be that they are both red shifted equally, one is blue one is red, or one is more red shifted than the other, surely. — MikeL

Nope. Your scenario would predict inhomogenities in red-shifting that we just can't see. If it is our relative motion that causes the effect, then we couldn't be moving towards some things without moving away from other things. There would be no way to conceal that fact.

The red shifting is just too precise and well behaved in every direction for our motion to be the cause.

You could imagine an inverse physics where instead of spatial expansion causing this even outward flow the story is that every point of space is contracting inwards. So the universe is a constant size in the global sense, but every point within it is shrinking smaller. That is kind of your contracting galaxies story.

But that would predict the sun and the milky way stars all receding from us too. Every point in space would have to be contracting inwards .... at lightspeed .... to invert the same physical picture.

As I said, actual galactic structure couldn't still exist. It would have all shrunk out of our sight. Even the good old sun would be a light-day "more distant" from us each morning when we wake up. Not to mention that we would have to junk quantum mechanics and its claims that physical action is tied to some actual minimum Planckian scale.

So your conjecture predicts observables we don't observe. And in the case of the sun rising tomorrow, the degree of error in the prediction is not small. It is astronomical. :)

Poor fool, I would tell him, that curvature is just a quamtum holographic projection of your own mind field. You can live in your reality and I'll live in mine. — apokrisis

https://resonance.is/observational-tests-holographic-cosmology/

"Quantum gravity offers such new physics unifying the cosmological and quantum scales and providing a complete model of our universe. However, although a consistent and validated model has yet to be agreed upon, it is expected to be holographic – that is the information of a volume of space is encoded on a boundary surface – as suggested by Nassim Haramein’s theory of quantum gravity, although the boundary surface is not regarded as literally 2-dimensional as it is comprised of 3D spherical planck oscillators. Now for the first time a team of scientist’s present observational proof that the Universe could well be holographic."


http://phys.org/news/2017-01-reveals-substantial-evidence-holographic-universe.html

"A UK, Canadian and Italian study has provided what researchers believe is the first observational evidence that our universe could be a vast and complex hologram."

https://arxiv.org/abs/1610.06236

"We show that the holographic principle can be understood heuristically as originated from quantum fluctuations of spacetime."

http://www.swansea.ac.uk/physics/researchgroups/particlephysicsandcosmologytheorygroup/holographyandphysicsbeyondthestandardmodel/

"Recently, the group began to apply the ideas of holography also to the construction of viable models of inflationary cosmology."

Yep. I can see how easy it is to confuse the holographic principle with literal holograms.

But that would predict the sun and the milky way stars all receding from us too. Every point in space would have to be contracting inwards .... at lightspeed .... to invert the same physical picture. — apokrisis

Yeah, I have no problem with that if it is the case that we have not actually observed any motion but only a snap shot through the telescope. Our time scale v the universe time scale suggests we've not tracked from A to B yet in our observations.

It well may be the case that space is contracting. Have we observed the reverse of any of this either? I mean are we a light-day "closer" to the sun every day, to take the opposite view of your example?

I don't know about the Plank scale. I'll have to check it out.

Bergson, Robbins, and myself are pretty much on the money. Apparently you do not understand the references provided. Exactly what what was being proposed as a holographic model of the universe. I'll fill this page with references and I'm bookmaking them for future replies.

Meanwhile back in the real world, physicists make it clear that they are making an analogy. A hologram is some real physical pattern. The holographic principle is about the theories you could write that can measure observable events described in information theoretic terms.

So the Universe may be LIKE a hologram. No one is saying the Universe IS a hologram. (Outside of the usual misleading reader-grabbing headlines.)

In the everyday world, a hologram is a special kind of photograph that generates a full three-dimensional image when it is illuminated in the right manner. All the information describing the 3-D scene is encoded into the pattern of light and dark areas on the two-dimensional piece of film, ready to be regenerated. The holographic principle contends that an analogue of this visual magic applies to the full physical description of any system occupying a 3-D region: it proposes that another physical theory defined only on the 2-D boundary of the region completely describes the 3-D physics.

http://www.phys.huji.ac.il/~bekenste/Holographic_Univ.pdf

https://www.sciencedaily.com/releases/2017/01/170130083231.htm

"A UK, Canadian and Italian study has provided what researchers believe is the first observational evidence that our universe could be a vast and complex hologram. Theoretical physicists and astrophysicists, investigating irregularities in the cosmic microwave background (the 'afterglow' of the Big Bang), have found there is substantial evidence supporting a holographic explanation of the universe -- in fact, as much as there is for the traditional explanation of these irregularities using the theory of cosmic inflation."

http://m.nautil.us/blog/new-evidence-for-the-strange-idea-that-the-universe-is-a-hologram

"In their paper, published last month in Physical Review Letters, the team report the holographic model fitting the Planck satellite data slightly better than the standard model. The results don’t prove the universe is holographic, but they are consistent with a holographic model."

Yep. Back in the real world, the analogy is still proving useful to try and explain stuff to lay folk.

https://www.southampton.ac.uk/news/2017/01/holographic-universe.page

"Professor Kostas Skenderis of Mathematical Sciences at the University of Southampton explains: “Imagine that everything you see, feel and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field. The idea is similar to that of ordinary holograms where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire universe is encoded!”

https://www.sciencealert.com/this-might-be-the-first-observational-evidence-that-our-early-universe-was-a-hologram

"So like a 3D hologram projected from a two-dimensional screen, the hypothesis states that the three dimensions of our Universe were projected from a two-dimensional boundary.

Since 1997, more than 10,000 papers have been published supporting the idea, so it’s a lot less crazy than it sounds.

Now Afshordi and his team report that after investigating irregularities in the cosmic microwave background - the 'afterglow' of the Big Bang - they’ve found strong evidence to support a holographic explanation of the early Universe.

"Imagine that everything you see, feel, and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field," says one of the team, Kostas Skenderis from the University of Southampton in the UK.

"The idea is similar to that of ordinary holograms, where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire Universe is encoded."

https://youtu.be/HnETCBOlzJs

I am a great believer in Science, and at the same time the most skeptic of all.

https://philpapers.org/post/17142

edit: maybe more to the point, I found those two posts that more directly relate to the phase of the discussion. But let me state that I have no opinion on whether the universe is a hologram or not. I am afraid it is way above my pay grade!

https://philpapers.org/post/17290
https://philpapers.org/post/17298