a-cosmology-group/acg#314

There is no such universal origin point in my model.

(There isn’t one in the superficially related de Sitter universe either.)

All that really matters is that a clock near the observer runs at 1x normal speed to them, and distant clocks run at $\frac{1}{1+z}$.

So distance causes time dilation which causes redshift. I get the picture. Your model is just some math - physics plays no part in it.

So distance causes time dilation which causes redshift.

I didn’t say anything like that.

Your model is just some math - physics plays no part in it.

If you mean in the sense of controlled experiments and the like, yeah, cosmology is more of an observational science than hard physics.

If that’s not what you mean, please elaborate.

The basis of this little digression is this comment of yours: >My current conjecture is that time is speeding up, and therefore time was slower in the past. Light doesn’t actually redshift on its way through the universe. It basically started it out like that.

That was in response to this question: >…to what do you attribute the cause of the redshift and why isn’t it reflected in the math?

All I’ve been trying to determine is the causal mechanism for the redshift in your model. Given your response and subsequent remarks, it appears you don’t have a coherent physical explanation. It also appears that you don’t seem to understand why that is a problem for a scientific model.

The basics are this. Energy of a photon is frequency times Planck’s constant, $E=hf$.

Suppose EM radiation was emitted at 8 THz.

And then time (i.e., clocks) sped up, to double the speed when the EM was emitted.

It is observed as 4 THz when measured on a contemporary clock.

It only lost energy because the clock its frequency is compared against has changed rate.

There is no preferred clock rate in this scenario. There is the observer at z=0, and past clocks at z>0.

Time speeds up is not a meaningful physical statement. It’s no different than the space expands story. It’s not physics.

There are basically two theories that may serve as an explanation for the cosmic redshift in a non-expanding universe: Tired Light and Variable Mass. From Unification of Variable Mass and Tired Light it is concluded that TL and VM are mutually incompatible.

Tired Light:

Variable Mass:

Both the Time Dilated Past hypothesis by @mikehelland and The Jeans Contraction by @rajbooth are compatible with Variable Mass as the underlying mechanism.

Time speeds up is not a meaningful physical statement. It’s no different than the space expands story. It’s not physics.

@budrap00 . That depende on how you define “time”. Let Google be your friend: >Definition. The second is defined by taking the fixed numerical value of the caesium frequency ∆ν, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to $s^{−1}$.

Atomic clocks in principle can be running faster or slower. The latter is the certainly the case with Variable Mass. Now if time is defined by the number of clock ticks of an atomic clock, then this can be translated into time itself running faster or slower.

@HanDeBruijn Defining a unit of time does not constitute a definition of time any more than defining a meter means you have defined the meaning of distance (or space, the aggregate of distances). The question of whether space and time are substantial entities or merely relational concepts is an ancient philosophical debate. Here is how it is framed from a philosophical perspective: >What is space? What is time? Do they exist independently of the things and processes in them? Or is their existence parasitic on those things and processes? Are they like a canvas onto which an artist paints; they exist whether or not the artist paints on them? Or are they akin to parenthood; there is no parenthood until there are parents and children? That is, is there no space and time until there are things with spatial properties and processes with temporal durations?

–– https://plato.stanford.edu/entries/spacetime-holearg/

My argument in this regard is that while space and time are clearly descriptive of the observable relationships between objects and events, there is absolutely no empirical evidence to justify the claim that they are substantival, and therefore causally-interacting, entities. Assuming they are substantival is no more justifiable than assuming dark matter or dark energy etc. as a means to explain observations.

Atomic clocks in principle can be running faster or slower.

In principle, the laws of thermodynamics run in both directions but in physical reality they only run in one direction. All clocks, in empirical reality, run slower in gravitational fields or accelerating systems. The clocks run slower the steeper the gravitational gradient or higher the acceleration. Those are observed phenomena. Invoking a variation in clock rate without providing a physical explanation for why the clock rate has changed is metaphysical handwaving similar to “redshift is caused by the expansion of space.” It’s not physics.

@budrap00 . >In principle, the laws of thermodynamics run in both directions

Please explain: I have never seen running laws. Do you mean: run in both time directions? >Invoking a variation in clock rate without providing a physical explanation for why the clock rate has changed is metaphysical handwaving similar to “redshift is caused by the expansion of space.” It’s not physics.

I beg to differ.

• It is perfectly allowable to have a working hypothesis in physics with an underlying explanation yet to be found.
• With the Variable Mass theory there is “Jeans Contraction”, meaning that material bodies (and light waves too) are shrinking. This is equivalent with saying that empty space is expanding (because it is measured by shrinking matter).

Physics is still a philosophy but requires a bit more than words and gestures. It is still the philosophy where the loudest person in the room doesn’t always win. However we need to present arguments with reasoning for others to test or falsify. Even though maths ensue, reasoning still needs to be present, lest you end up with quarks.

Here is why time is substantive. Here is why space is substantive. OK, rather, time is emergent from space …

• There are (at least) two ways to achieve a time dilation, or a slowed clock

1. Acceleration (and this includes gravity)
2. Velocity in empty space.

It is possible to get the same amount of time dilation of e.g. a slowed clock on the surface of earth as by reaching a velocity of 11km/s in free space. 11km/s is also the escape velocity on earth surface, meaning standing in a gravity well on the surface of earth is the same as if you are traversing space at 11km/s - as far as clocks go.

The problem is getting past the relativity because at the moment nobody knows how much their times are already dilated. Set that aside for a moment and choose any frame as your reference to start off.

Then the common denominator that is causing clocks to slow is space - asymmetric space, or curved space if you will.

• Asymmetric space will accelerate you down the gradient of asymmetry (Einstein gravity).
• When you accelerate (using a force) you create an immediate asymmetry with space (inertial effects - mass is a resistance to acceleration).
• When you travel at speed v you are at an asymmetry with space (doppler effects)

This last one says space IS the cosmic timeframe.

And so it is (in theory) also possible to stop a clock by reaching a velocity v=c, or to be on the horison of a black hole, both dubiously inachievable goals. Cesium clocks may be a standard, but the clocks need to be normalised based on gravity at the lab. You can’t go measure it on top of Everest and think you’ve just made the whole universe faster. :)

However, it is evident that the roleplayer causing time dilation is interaction with space. Call it spacetime if you will, or call it aether.

@budrap00

Time speeds up is not a meaningful physical statement. It’s no different than the space expands story. It’s not physics.

That’s just your opinion.

In any case, the farther things are, the more redshift they have. Redshift is when the frequency and energy of a wave (E = hf) go down.

We also see distant objects as stretched in time. It gives the appearance that clocks were slower in the past.

In the standard model, that time dilation is an optical illusion caused by the expansion of space.

My proposal is that it is not an optical illusion, nor the effect of some other cause. Our eyes aren’t playing tricks on us, and neither is the Cosmos. Time was actually slower in the past.

Electromagnetic waves emitted millions of years ago are received by an observer with a faster clock rate, and thus the measured frequency and energy are lower.

It’s just an idea. And it doesn’t have deeper implications for the true nature of time or space. It’s a mathematical tool for describing measured phenomena.

@mikehelland >It’s just an idea. And it doesn’t have deeper implications for the true nature of time or space. It’s a mathematical tool for describing measured phenomena.

I agree. It’s just some math slathered on an empirically baseless idea, that doesn’t say anything meaningful about physics. Which brings up this difficulty that mathematicism has with physical reality:

BR: >Time speeds up is not a meaningful physical statement. It’s no different than the space expands story. It’s not physics.

MH: >That’s just your opinion.

No, my statement is, in fact, based on the fact that there is absolutely no empirical evidence to support your belief in a physical thing called time that speeds up, thus causing the light from distance galaxies to be redshifted. I’ve pointed out this absence of empirical evidence repeatedly and you repeatedly ignore that fact. You are, as a politician once pointed out, entitled to your own opinions but not to your own set of facts. That there is no scientific basis for your belief in a causally interacting time is a factual statement.

@HanDeBruijn >Please explain: I have never seen running laws. Do you mean: run in both time directions?

Yes, of course. Thank you for pointing out the elision. I’m glad you were able to figure it out on your own.

It is perfectly allowable to have a working hypothesis in physics with an underlying explanation yet to be found.

That is true only if there is some possibility of the hypothesis being empirically verified. An idea like “material bodies (and light waves too) are shrinking” cannot be empirically verified because all observational instruments in that context are also shrinking, thus making the idea indistinguishable from “not shrinking.” In that light the Variable Mass model is neither a theory nor a hypothesis, just an unverifiable conjecture. (The VM model also seems to assume a universal time frame in which our “here and now” has some cosmological significance.)

@Francois-Zinserling >However, it is evident that the roleplayer causing time dilation is interaction with space. Call it spacetime if you will, or call it aether.

Rather than invoking metaphysical concepts, why not consider the thing that is observably part of physical reality, the Ambient Electromagnetic Radiation that is everywhere present in the Cosmos where you require spacetime or an aether. The AER is what’s there, not spacetime or an aether.

Neither standard model takes any account of the AER even though it is ubiquitous; the theorists are all too busy - dreaming up imaginary models full of things that aren’t there - to pay any attention to physical reality. This unscientific trainwreck is the direct consequence of the mathematicist framework that overwhelmed science @ 1980 and brought about the default, post-empirical regime of modern theoretical physics where the effluvia of hyper-mathematical imaginations now dominates the scientific landscape.

@budrap00 writes: >In principle, the laws of thermodynamics run in both directions but in physical reality they only run in one [time] direction.

The first half of thet statement is false. It is just another >difficulty that mathematicism has with physical reality

It happens that @mikehelland has written an excellent piece of text about it:

The Arrow of Time

Herewith the whole problem is actually solved, but it seems that nobody (except me) has noticed. Very much related: Upwind differencing scheme in Finite Volume Method (FVM) .

It happens that @mikehelland has written an excellent piece of text about it:

The Arrow of Time

Wow! How did you find that? I wrote that a long time ago.

@budrap00 . >An idea like “material bodies (and light waves too) are shrinking” cannot be empirically verified because all observational instruments in that context are also shrinking, thus making the idea indistinguishable from “not shrinking.” In that light the Variable Mass model is neither a theory nor a hypothesis, just an unverifiable conjecture.

Quite on the contrary. The Variable Mass model makes testable predictions. To mention a few:

• The Shrinking Kilogram may be related to the Age of the Earth
• The secular retardation of the spin motion of the Earth is calculated
• A proof of : $(\mbox{leap seconds in century}) = (\mbox{century})^2 / (\mbox{age of the earth})$

(The VM model also seems to assume a universal time frame in which our “here and now” has some cosmological significance.)

The VM model does not assume a universal time frame and its “here and now” is precisely what it says, i.e. nothing cosmological.

By the way @HanDeBruijn, the “shrinking kilogram” happened because the piece of metal had to be cleaned regularly to remove layers of Parisian pollution that would collect on its surface. The cleaning process also removed a bit of metal at the same time.

We know that the mass of “Le Grand K”, the official kilogram, was decreasing relative to several other standards, made of the same material, but kept in a better atmospheric environment. The mass of these kilograms did not change by the same amount, in contradiction with the Variable Mass Model. Your first point is not a valid argument against @budrap00 statement.

@RedshiftDrift . Any evidence is a coincidence in the eyes of a non-believer. >We know that the mass of “Le Grand K”, the official kilogram, was decreasing relative to several other standards, made of the same material, but kept in a better atmospheric environment.

The better atmospheric environment is exactly the problem. The official kilogram has not been shrinking; it has remained the same, while the other kilograms have become heavier. Very much related is my contribution to the thread What mechanism(s) drives plate tectonics? .

@mikehelland >How do you determine what is physics and what is not?

All of science, including physics, is the study of the phenomenological world. It is the study of those things that can be directly observed, measured, or detected. It is not supposed to be, although that is what academic theoretical physics has become, the study of mathematical models based on mathematically convenient conjectures such as expanding space, speeding up time, shrinking matter, dark matter, dark energy, quarks, and on, and on, and on…

You and others here clearly understand that the standard model of cosmology is a failure. That’s a good thing, but you apparently think you can use the same math-first methodology that is the root cause of this mess, to create a better model. You can’t. Because math is not physics. You can’t seem to grasp that simple fact. You and others can’t even discuss physics without employing a mathematical framework. You don’t seem to understand physics at all, only mathematical models.

I don’t think this is a personal failing of anyone’s. It is a product of your education which no doubt took place post-1980 when academic science plunged off the sturdy rails of empiricism into the thickets of illogic provided by the cult of mathematicism. You don’t know how to think about physics because physics hasn’t been taught in the academy for 40+ years, only mathematical models.

Because math is not physics.

If it’s math, that doesn’t make it physics.

And if there is no math, it’s definitely not physics.

You don’t know how to think about physics because physics hasn’t been taught in the academy for 40+ years, only mathematical models.

Give us some examples of “true” physics then.

Also, this is all just a philosophical aside. I’ve already argued that cosmology is not physics. For starters, we can’t do controlled experiments on the cosmos.

And if there is no math, it’s definitely not physics.

That’s what you were taught alright but that is simply wrong. You can do physics without math with just observations and measurements - no math required. But no amount of math can turn abstract theories into physics. You can’t make geocentrism into physics with epicycles and you can’t make speeding-up light cause a cosmological redshift just because you have some math.

When Galileo pointed his telescope at Jupiter or apocryphally dropped different weights from the Leaning Tower of Pisa he wasn’t doing math. Faraday did physical experiments - he did not have or need a mathematical model. The double-slit experiment is not math. Passing light through a prism is not math. When Feynman took a piece of o-ring material and immersed it in ice water to test it during the hearings about the Challenger disaster he was doing physics, not math.

@mikehelland >Also, this is all just a philosophical aside. I’ve already argued that cosmology is not physics. For starters, we can’t do controlled experiments on the cosmos.

Well, for starters science does not require controlled experiments, like math they are useful tools but they do not define science. You can’t do controlled experiments on the Solar System either or the Sun, Moon, Jupiter etc.

Modern cosmology is not physics because modern cosmologists spend their entire careers trying to squeeze every new physical observation of the Cosmos into a model based on 100 year old assumptions that don’t make any sense in terms of known physics. But cosmological physics involves scientific observations and measurements which we have compiled in great number over increasing radial distances over the course of the last century.

What is required of cosmologists at this point is that they assess all those new (<100 years) observations without the intellectual blinders of the standard model, and come to some qualitative understanding of how the Cosmos is structured. At that point mathematical models can be used to fine-tune our qualitative understanding - as long as the math correlates with the physics and doesn’t invoke purely metaphysical, philosophical or mathematical conceits to “explain” observations. Such nonempirical conceits only indicate that the mathematical model under consideration is inadequate to the task of accurately representing the physics.

In terms of modern cosmology, the FLRW model’s assumption of a universal frame is the geocentrism of our day - it is simply wrong, because it is incompatible with our knowledge that the speed of light has a finite maximum. I understand that you and @HanDeBruijn claim that your cosmological models do not assume a universal frame but you both use “the Past” in a way that implies just such a frame - by attributing a universal-scale significance to our local perception of the past. The light we observe in our here and now, that was emitted by any 10Gly distant galaxy was emitted in that galaxies here and now.

If there can be any meaning to the Cosmological Principle then the conditions at any 10Gly distant galaxy, at the time the light we observe was emitted, should have been similar to the conditions in our here and now. If the conditions were different (in a similar way) at all of the galaxies 10Gly from us then you are invoking a frame that is both geocentric and universal.

The galaxies that are 10Gly distant in our local frame do not share a physically meaningful common “Past”. In the relativistic Cosmos those galaxies have their own unique frames and there is no common frame that unites them physically. Their commonality is trivial - it exists only with respect to their position in our local frame. They all lie coincidentally on our 10Gly horizon. That correlation is only from our point of view and it has no physical significance beyond that. If you imbue it with physical meaning then you are invoking a geocentric, universal frame.

There must be a frame though, even if you were to start of, and only define the frame as ‘the laws of physics’, because the 10Gly distant galaxy appears to have the same rules and laws as our own. It is not entirely ‘unconnected’.

It does appear as though you are fighting the status quo, yet you also appear to have adopted their rejection of an aether. In an earlier post you said:

Rather than invoking metaphysical concepts, why not consider the thing that is observably part of physical reality, the Ambient Electromagnetic Radiation that is everywhere present in the Cosmos where you require spacetime or an aether. The AER is what’s there, not spacetime or an aether.

I see your AER, and I raise you because, A random distribution of (remnant) ER cannot enforce the laws in the same way everywhere. It has to be a ‘specific’ ER. Like e.g. the strength of vacuum that QM found to be at the order of $10^{120}$ and rejected as implausible. And it has to ensure that the strength of gravity (and the Coulomb attraction) is the same ‘everywhere’ (with exceptions in the extremes).

It can also not be our average observed ER, no matter the intensity, because almost none of those would penetrate the earth, past the moon, and still do its business on the other side without cooking everything inbetween. Since we do not see the cosmos shine brighter than the sun, I expect the strength of the remnant ER to be orders weaker (than the sun). How then can this AER define both gravity and Coulomb attraction within and on the sun itself?

On the other hand, an aether of order $10^{120}$ would be just what I expect to cause electromagnetic effects, making opposites attract and ticking the clocks of elementary particles. Larger structures would be unaffected by this aether, just as e.g. a radio antenna ignores UV rays.

The reason I do not believe in the aether is that it cannot be directly observed, measured, or detected. Therefore it can only be believed in. Science is the study of those things that can be directly observed, measured, or detected.

Science is not the study of things that can only be believed in on the basis of circular arguments stemming from philosophical, metaphysical, or mathematical considerations that hold the belief a priori.

@budrap00

You can do physics without math with just observations and measurements - no math required.

Only by some strange definition of physics.

If you have a cannon and want to hit a target that’s a half mile away, with enough cannonballs, you could through trial and error eventually hit it.

Or, you could do some physics, i.e., math.

When Galileo pointed his telescope at Jupiter

That’s astronomy. That some stars seem to make different sized bear shapes in the sky isn’t “physics”.

or apocryphally dropped different weights from the Leaning Tower of Pisa he wasn’t doing math.

That’s a rather odd claim.

https://www.physicslab.org/Document.aspx?doctype=2&filename=Kinematics_GalileoRamps.xml

Kind of sounds like you’ve got something against math.

@mikehelland

Kind of sounds like you’ve got something against math.

I have nothing against math. As I have stated repeatedly in this venue I understand math to be a useful and necessary tool of science. But it is only a tool; it is not science, and slapping some math on a metaphysical conceit like speeding-up time doesn’t turn that metaphysics into science.

Unfortunately you appear to have no framework other than the mathematicism you learned in school for dealing with that criticism, And since that criticism is ultimately of mathematicism and its by-products you find yourself defenseless.

As for the rest of your remarks they follow a standard mathematicist template: spew a few non sequiturs and illogical remarks in hopes of diverting attention from your inability to defend mathematicism. Here is a classic example. To my argument that Galileo wasn’t doing math when he pointed his telescope at Jupiter, you responded with this remark:

That’s astronomy. That some stars seem to make different sized bear shapes in the sky isn’t “physics”.

I’m not going to follow you down that contrived black hole of historical ignorance and sheer illogic. That’s the point after all, isn’t it? Let’s change the subject. Nope. I’ll just let it stand there as a testament to your profound inability to defend your mathematicist beliefs.

I understand math to be a useful and necessary tool of science.

Fair enough. You were making it sound like it was unnecessary.

But it is only a tool; it is not science, and slapping some math on a metaphysical conceit like speeding-up time doesn’t turn that metaphysics into science.

Then just don’t make that assumption.

Making mathematical models is just another part of finding patterns in the shadows on the cavewall.

I personally prefer Julian Barbour’s take on time, that change is primary, and time is something we deduce from it. In other words, things don’t change in time; things change, and time is the result.

But however you view time, for the purpose of the conjecture, events appear to have unfolded at a slower rate in the past because they actually did, at least according to local clocks.

To my argument that Galileo wasn’t doing math when he pointed his telescope at Jupiter, you responded with this remark:

Pointing a telescope at Jupiter doesn’t necessarily require doing math (assuming you know where it is without needing coordinates), but it’s also not doing physics.

Chemistry, biology, astronomy, and physics are different branches of science.

…events appear to have unfolded at a slower rate in the past because they actually did…

That’s like saying the railroad tracks appear to converge in the distance because they do. You are essentially imposing on physical reality a simple point-of-view illusion. This becomes more obvious when you consider your use of the term past. If that past is only referring to our local clock’s past then you have to explain how the mere coincidence of two galaxies lying in equal (10Gly) but opposite directions from us uniquely determines their local clock rates to be running at the exact same slower rate than ours. I don’t think you can.

You can assume that the coincidental location causes their clocks to run slower, of course, but then that’s just a metaphysical conjecture without any justification in known physics, which is to say the conjecture doesn’t have any scientific basis. It’s the kind of thing mathematicism does all the time without producing any meaningful science.

Pointing a telescope at Jupiter doesn’t necessarily require doing math (assuming you know where it is without needing coordinates), but it’s also not doing physics.

What Galileo was doing was science and what he discovered by making his repeated observations of Jupiter was that Jupiter had moons that orbited it. This was a profound scientific discovery at the time since the common belief was that the Earth was the center of the universe. It was significant for both astronomy and physics. The math describing those orbital motions wouldn’t be worked out by Newton for another 75 years but the physics of the situation was an observed fact in 1610.

BR: >But it is only a tool; it is not science, and slapping some math on a metaphysical conceit like speeding-up time doesn’t turn that metaphysics into science.

MH: >Then just don’t make that assumption.

I don’t think see an assumption in the remark you quoted. If you believe otherwise please be specific about what you think the assumption was.

That’s like saying the railroad tracks appear to converge in the distance because they do.

In a sense.

We watch the sunrise and sunset, and the most natural explanation is that the sun moves around the Earth. We know that this isn’t the case though. It’s the Earth that moves around the sun.

I am in effect saying that the most natural explanation of cosmic time dilation is that things appear to have happened slower in the past because they did.

You are essentially imposing on physical reality a simple point-of-view illusion.

Given that it is a “simple” “illusion”, how do you explain cosmic time dilation? The only valid explanation out there now is expanding space.

And here you assume that there is something called physical reality and we all know what it is.

The hypothesis and the mathematics make no such assumptions. You do.

This becomes more obvious when you consider your use of the term past. If that past is only referring to our local clock’s past then you have to explain how the mere coincidence of two galaxies lying in equal (10Gly) but opposite directions from us uniquely determines their local clock rates to be running at the exact same slower rate than ours. I don’t think you can.

Since light travels at a finite speed, something that happened one light year away actually happened a year ago by the time it is observed here.

Do you have an issue with that concept?

I am in effect saying that the most natural explanation of cosmic time dilation is that things appear to have happened slower in the past because they did.

@mikehelland The keyword here is “appear”! Would you accept that distant objects “appear” to evolve more slowly because of an optical illusion?

STz shows that all frequencies, 1000 THz, 1 MHz, .1 μHz, etc., are reduced by a cumulative Doppler effect from electron recoil. The month-long SNe light curves are therefore stretched, not because “time was slower in the past”, but because of an optical effect that produces a redshift.

Here I agree with @budrap00 that using relativity to stretch time is the same as using relativity to stretch space. Instead of writing the metric

$$ 0 = -(ct)^2 + a(t)^2 \ ( {\rm d}x^2 + {\rm d}y^2 + {\rm d}z^2) \quad \quad \mbox{“stretching space”} $$

you propose to stretch time with

$$ 0 = -(c \ [t/a(t)])^2 + {\rm d}x^2 + {\rm d}y^2 + {\rm d}z^2, \quad \quad \mbox{“stretching time”} $$

or change the speed of light with

$$ \quad \quad \quad 0 = -([c/a(t)] \ t)^2 + {\rm d}x^2 + {\rm d}y^2 + {\rm d}z^2. \quad \quad \mbox{“stretching the speed of light”} $$

There is no observational difference between these models, physically they are the same. They are also mathematically equivalent.

The big issue with that concept is that it’s the Big Bang model expressed differently, with all the problems that come with mainstream cosmology.

From a metaphysical point of view, “stretching space-time coordinates” is a category error: the physical size of an object is not the same as “space”, and the rate of change of an object is not the same as “time”. Einstein correctly derived the equations of relativity, but these equations are incorrectly interpreted which leads to statements such as “space and time can be stretched” (it may be Einstein’s fault with his confusing statement ‘time is what clocks show’). Space and time are mental constructs that cannot be observed directly. It’s the objects we observe, rulers and clocks, that are described by physics.

@mikehelland writing to @budrap00 : >Kind of sounds like you’ve got something against math.

I would rather say that mathematics is not Bud’s strongest ability, as is apparent from

• The 4/3 Dimensional Ratio, refuted in one or two replies. But it is still on Bud’s website.
• Gravitational Redshift & Expanding Spherical Wavefronts with a few last replies in the accompanying thread.

@RedshiftDrift

Would you accept that distant objects “appear” to evolve more slowly because of an optical illusion?

If it can be shown how.

STz shows that all frequencies, 1000 THz, 1 MHz, .1 μHz, etc., are reduced by a cumulative Doppler effect from electron recoil. The month-long SNe light curves are therefore stretched, not because “time was slower in the past”, but because of an optical effect that produces a redshift.

So, I don’t totally grasp this. Are you saying the conditions for time dilation are only present around serupnovae? Or am I reading that wrong, and redshift is always equal to time dilation?

There is no observational difference between these models, physically they are the same. They are also mathematically equivalent.

Unfortunately for me, that isn’t true. $a(t)^2 dx^2$ means space is changing over time. $a(t)^2 dt^2$ means time is changing over time. In the world of differential geometry, that works out to be Minkowski spacetime, with no redshift or time dilation.

It took a number of people explaining it to me, including an MNRAS reviewer, along with me calculating the Christoffel symbols before I accepted that.

But the gist is, how a dimension changes over itself is always 1.

In any case, whatever metaphysics you get out of a mathematical model, you have to put into it first.

@RedshiftDrift

Space and time are mental constructs that cannot be observed directly. It’s the objects we observe, rulers and clocks, that are described by physics.

You say they are mental constructs yet you describe the exact methods (rulers and clocks) for measuring each of them … directly. That looks like physics to me.

I am in effect saying that the most natural explanation of cosmic time dilation is that things appear to have happened slower in the past because they did.

This again means that you see “the past” of our local, relational, spacetime frame as having a universal meaning or significance. Calling it “natural” is dependent on taking a classical view of the Cosmos - that it has a universal spacetime frame that is the same for all observers at any universal “here and now” moment. That is the fundamental error at the heart of Big Bang cosmology.

The problem, of course, is that such a universal “here and now” can only be imagined, not observed. Science is not supposed to be in the business of giving credence to imaginary things for which there is no possibility of empirical verification - otherwise we would still be discussing the number of angels that can dance on the head of a pin.

I would also point out that time dilation is an observed physical consequence between clocks at different potentials in a gravitational field. That makes attributing cosmic time dilation to a gravitational effect far more “natural” than attributing it to an unexplained effect related to an unobservable but “universal” spacetime frame, the very concept of which is at odds with basic relativity theory.

And here you assume that there is something called physical reality and we all know what it is.

The hypothesis and the mathematics make no such assumptions. You do.

Ah yes, another diversionary tactic, a desperate attempt to change the subject from the realm of scientific considerations, which do involve the experience of an objective reality, to the feckless musings emanating from some philosophy nerds. Sorry, I don’t have time for that kind of vapid, pseudo-profound, nonsense. If it’s your cup of tea, be my guest, but as far as I’m concerned, it’s just another one of those black holes of illogic I’m not going to chase you down.

I also don’t understand why you think that the inability of your “hypothesis” and its attendant math to discern an objective reality, is a selling point. Maybe it is in philosophy but in science it just means that you are not doing science.

This again means that you see “the past” of our local, relational, spacetime frame as having a universal meaning or significance.

How so?

If you existed 100 billion years from now, or 100 billion years ago, the cosmos would look basically the same.

@RedshiftDrift . >using relativity to stretch time is the same as using relativity to stretch space.

There is a more elementary way to see this. Assuming a Circular orbit as a good approximation, we have according to good old classical mechanics for the orbital period $T$, say a year on earth, and for $r=$ distance from earth to sun:

$$ m \omega^2 r = G\frac{m M}{r^2} \quad \Longrightarrow \quad \omega = \sqrt{\frac{GM}{r^3}} \quad \mbox{with} \quad \omega = \frac{2\pi}{T} $$

$$ T = 2\pi\sqrt{\frac{r^3}{GM}} \quad \mbox{: time} \qquad \mbox{OR} \qquad r^3 =\frac{GM}{(2\pi/T)^2} \quad \mbox{: space} $$

where $G=$ gravitational constant, $M=$ mass of the sun. Now suppose we adhere to the Variable Mass theory, then with increasing $M$ we have, compared to here and now $(0)$ :

$$ \frac{T}{T_0} = \sqrt{\frac{M_0}{M}} \qquad \mbox{OR} \qquad \frac{V}{V_0} = \frac{M}{M_0} \quad \mbox{with} \quad V = \frac{4}{3}\pi r^3 $$

If we take one of the two and not both: Time is speeding up OR Space / Volume is expanding (towards the future). Some people have made a choice and prefer to take Time (Dilated Past) only.

@mikehelland >Are you saying the conditions for time dilation are only present around serupnovae? Or am I reading that wrong, and redshift is always equal to time dilation?

Redshift, time dilation, and a variable light speed are all correlated in a gravitational gradient.

@mikehelland >If you existed 100 billion years from now, or 100 billion years ago, the cosmos would look basically the same.

That’s right, but in your model time is speeding up so clocks in the past ran slower than now and clocks in the future will be running faster. The Cosmos in your model not only looks different in different epochs but is/was/will be different - due to a metaphysical cause, speeding-up time. At least that’s the best I can make of your arguments which however do seem to straddle the distinction between “what is” and “what is observed”.

For instance in this exchange: MH: >…events appear to have unfolded at a slower rate in the past because they actually did…

BR: >That’s like saying the railroad tracks appear to converge in the distance because they do.

MH: >In a sense.

Well, railroad tracks don’t actually converge. Yet you seem to be claiming that the observation of distant clocks running slower is not due to a POV illusion but that the clocks were actually running slower in “the Past.” But that gives “the Past” a universal significance and imbues it with a substantive difference, i.e. the universe of “the Past” was different than universe of the present, which seems to contradict the above quote. It also means you have a universal frame.

In short your various explanations don’t seem to hold together. Either the clocks on distance galaxies actually ran slower or they only appear to run slower. Your answers to that basic question are ambiguous - in a sense.

The Cosmos in your model not only looks different in different epochs but is/was/will be different

It would always look the same. The observer would always think their clock is normal, and past clocks are slower. Future clocks cannot be observed.

It would always look the same. The observer would always think their clock is normal, and past clocks are slower.

Ok, fine, all clocks are running at the same rate locally. That means that something must be happening to the electromagnetic radiation in the interval between emission and observation. What then is the physical mechanism that causes the observed cosmological redshift and cosmic time dilation in your model?

Ok, fine, all clocks are running at the same rate locally. That means that something must be happening to the electromagnetic radiation in the interval between emission and observation. What then is the physical mechanism that causes the observed cosmological redshift and cosmic time dilation in your model?

So, imagine you shoot a pulse of light into space every 1 second, for 10 seconds.

The light travels at a finite speed and arrives some where to some observer in the cosmos sometime in the far future.

That observer measures 2 seconds between each pulse. What happened?

We’re in the present, the ones emitting the pulse of light every one second. Let’s give our clock rate, the rate at which things happen in the universe, an arbitrary value of N.

Now suppose as the light travels, clocks everywhere speed up, meaning everything speeds up.

By the time our pulses reach that distant observer, clocks are going 2N.

Every pulse reaches the observer 1 second apart if you were using the old N clock rate. But the observer’s clock hands spin twice as fast as the emitters. So it counts two seconds between each pulse.

You can replace the pulses with a frequency and wavelength, and see that the frequency goes down. Which meant its energy has gone down. E=hf

Since light always travels at c locally, as clocks and events of the universe speed up, it has to speed up as well, to remain at c with local clocks. The speed of a wave is v = wavelength * frequency. You can’t produce a higher frequency in traveling light any more than you can turn 10 pulses in 20. But you can increase the wavelength.

So the frequency\energy go down do to an increasing local clock rate, and the wavelength goes up to keep that light traveling at c.

I’m not suggesting there is a physical mechanism that causes the clocks/everything to speed up. That’s just a postulate. It’s a proposed principle of nature, and not as an effect of some other cause.

What physical mechanism, for instance, keeps light traveling at c? You don’t need one. You postulate it. That’s the hypothesis in a nutshell.

@mikehelland writes: >I’m not suggesting there is a physical mechanism that causes the clocks/everything to speed up.

The Variable Mass theory (VM) is a physical mechanism that causes the clocks/everything to speed up. By its very nature, it is in close agreement with the Time Dilated Past hypothesis, as shall again be demonstrated here. There are two ways to do it. The first way is via Narlikar’s Law. In the common sloppy notation: Replace $t\rightarrow T$ with $T=$ orbital time (because we are dealing with Einstein’s theory / Gravity). And shift the origin of time to here and now, where $m=m_0$ for $T=0$. This has previously been done in “Breakdown of the Newton–Einstein Standard Gravity at Low Acceleration in Internal Dynamics of Wide Binary Stars”, giving

$$ \frac{m}{m_0} = (1+T/A)^2 $$

Another central result in (my version of) the Variable Mass theory is

$$ \frac{dT}{dt} = \sqrt{\frac{m}{m_0}} \qquad \mbox{or} \qquad \frac{dt}{dT} = \sqrt{\frac{m_0}{m}} $$

where $T=$ orbital time, $t=$ atomic time, $m=$ mass, $A=$ Age, $(0)=$ here and now. It follows that

$$ \frac{dt}{dT} = \frac{1}{1+T/A} \quad \Longrightarrow \quad t = \int\frac{dT}{1+T/A} = A.\ln(1+T/A) + C $$

where $C=0$ because of the initial condition $T=t=0$. And so the outcome is similar to one in the Time Dilated Past theory.

$$ 1+T/A = e^{t/A} \quad \mbox{provided that} \quad A = \frac{1}{H} \quad \mbox{and} \quad T = \tau $$

The second way is to start with the Time Dilated Past hypothesis. In Mike’s notation we copy:

$$ \frac{1}{1+z} = e^{Ht} $$

where $z=$ cosmic redshift, $H=$ Hubble parameter, $t=$ Expanded time, to be renamed here to Atomic time. According to VM, the cosmic redshift is caused by smaller elementary particle (rest) mass $m \lt m_0$ in the past:

$$ 1+z = \frac{m_0}{m} \quad \Longrightarrow \quad \frac{m}{m_0} = e^{Ht} $$

And here we go the other way around.

$$ \frac{dT}{dt} = \sqrt{\frac{m}{m_0}} = e^{H/2.t} \quad \Longrightarrow \quad T = \int e^{H/2.t} dt = \frac{e^{H/2.t}}{H/2} + C $$

With the initial condition $T=t=0$ it follows that $C = -2/H$ and so

$$ 1+\frac{H}{2}T = e^{H/2.t} \quad \Longrightarrow \quad \left[1+\frac{H}{2}T\right]^2 = e^{H.t} = \frac{m}{m_0} $$

Leading back to Narlikar’s Law on the right. On the left we see that Mike’s Minkowski time $\tau$ is similar to our Orbital time $T$. However, in this derivation (and Narlikar’s theory too) the Hubble parameter is related to Age by

$$ H = \frac{2}{A} \quad \mbox{or} \quad A = \frac{2}{H} \qquad \mbox{instead of} \qquad H = \frac{1}{A} \quad \mbox{or} \quad A = \frac{1}{H} $$

Therefore the cosmos with Variable Mass is twice as old as usual. In Orbital time $T$; in Atomic time $t$ it is eternal.

You say they are mental constructs yet you describe the exact methods (rulers and clocks) for measuring each of them … directly. That looks like physics to me.

Having a measurement method for time and space is physics, but it doesn’t tell us what time and space are (which is metaphysics for now).

@RedshiftDrift ah, yes, you mean just like gravity?

We can vary clock-rates in a varying gravity but, since we don’t know what causes gravity, there is still a metaphysics component in there. Yet we have figured out a way to measure gravity by its effect on mass (which we also don’t really know what it is) and thereby it’s ok to give each a name and it’s no longer metaphysics.

Our difficulty in comprehending this is that we still intuitively see gravity as something ‘coming out of a mass’, where-as it is more reasonably an effect of asymmetric space (Einstein GR or curved space) around a mass. Then do not think of varying clocks by placing it on top, or at the bottom, of a mountain, but rather think how space could behave different in these two locations. In this case space is causing the different clock rates AND space is causing a different acceleration (gravity) toward the mass at those two locations.

It’s not hard to understand that space is causing gravity, unless one is a complete Einstein dissident. It’s harder to accept that space is causing atom clocks to ‘tick’ thereby causing time to flow at that location.

There we now have two more ways to measure space. At what point will it no longer be metaphysical?

So we’re back at a universal time frame where all clocks at some uniform distance from us were uniformly running at a rate slower than the clocks of our supposedly universal now - or maybe they weren’t.

The distance and location is not important, so it seems I’m not describing it quite so clearly.

Let’s start with a basic Euclidean 3D space filled with abstract clocks.

Let’s assume all those clocks tick at the same rate.

And let’s assume, they will also tick at the same rate. Like a 200 MHz CPU from decades ago. It run at 200 MHz when it was new, it runs at 200 MHz today.

Absent any gravitational forces, that’s basically what we’re assuming is the case.

What physical mechanism enforces that? Why do we assume that’s true?

It’s your model. You have to explain your assumptions, not me.

If there isn’t any particular reason that time should always flow at the same rate for eternity, there isn’t any particular reason it can’t speed up either.

No one has observed flowing time - no one ever will because time is only a relational concept, that’s all the scientific evidence supports. Flowing time and expanding space are metaphysical concepts that have nothing to do with the way physical systems behave. They may be in your math in the same way that epicycles are in Ptolemy’s math but they are not part of observed physical reality and they play no causal role in physical reality. Speeding-up time is in your model? That’s nice but it means your model is not a scientifically accurate representation of physical reality - it’s just some math.

What is the scientifically accurate representation of physical reality?

I’m glad you know what it is. That saves everyone the trouble of finding models that predict its behavior.

Scientifically accurate representations of physical reality describe the behavior of those things that can be directly observed, measured, or detected (physical reality) without invoking unobservable, metaphysical “helpers” to ease the burden on mathematicists who don’t seem to understand that science is supposed to be the study of physical reality. Science is not supposed to be the study of mathematical fantasias concocted by mathematicists who are uncertain about the distinction between objective physical reality and their subjective metaphysical conjectures of mathematical convenience.

Since academic science blundered into the mathematicist weeds going on 50 years ago it has been in an almost constant state of crisis, with no end in sight. Mathematicism has produced the two ludicrously absurd, incoherent, and illogical standard models of theoretical physics, that do not bear any resemblance to the physical reality we actually observe. As far as I can see you’re just trying to pour the same old mathematicist wine into new bottles. A different set of metaphysical assumptions to replace the current ones will only perpetuate the problem not fix it.

To fix it you would have to start by closely studying physical reality without the blinders of the misbegotten standard models and their empirically baseless assumptions. I understand that this would be difficult for people who only comprehend the world through math and consider physical reality background noise that can be tuned out for the most part.

You keep saying what “physical reality” is over and over without realizing that you’re making tons of assumptions about it while doing so, and not actually saying anything meaningful.

And why a mathematical model should be taken as somehow encoding deep fundamental metaphysical truths is beyond me.

You basically make a bunch of assumptions, just to rail against them. There’s a name for that.

@budrap00 I think it is you who are playing the Ptolemy part in this argument.

There is enough evidence to suggest that time flows and there is enough evidence to show that time can flow at different rates at different locations. From those locations everything else appears to speed up or slow down. This is good established physics.

It’s not an absurd hypothesis to test if time flowed differently at different epochs. I may not buy in, but still, this is good physics in my opinion.

Agreed, time doesn’t need to be something physical, but it may be the measure of something physical. Just like ‘length’ is not physical but is another tool in the physics tool-bag. If only we could agree on what time is a measure of.

@mikehelland >And why a mathematical model should be taken as somehow encoding deep fundamental metaphysical truths is beyond me.

I have no idea what that is supposed to mean but my problem with your metaphysical explanation (speeding up time) for observed physical phenomena (cosmological redshift and cosmic time dilation) is precisely that being metaphysical means the “explanation” has no scientific value or meaning. It’s just some math.

As with your difficulty comprehending the concept of a physical reality that exists independently of your subjective belief system, you seem unable to distinguish between the separate realms of physics and metaphysics. That is not a good foundation for doing science.

Earlier in this thread you alluded to Plato’s allegory of the cave dwellers chained in such a way that they could only see the shadows of the world beyond playing out on the cave wall. I never saw much in that. The point seemed to be that there was a deeper, more perfect reality underlying the phenomenological world of experience, that could not be directly accessed. The problem for me was the nature of the chains that were preventing the cave dwellers from turning around and examining the world as it is. To Plato they just seem to be inherent in our human condition but undefined otherwise.

In light of our recent conversation I have now come to think of the Plato’s allegory as being trenchant to understanding the state of modern theoretical physics. Theoretical physicists are the cave dwellers who are not permitted to directly observe the phenomenological world but in this case the chains are simply the mathematicist beliefs that only allow them to observe mathematical shadows cast by external physical reality on their internal subjective reality - the chains are self-imposed.

@Francois-Zinserling >If only we could agree on what time is a measure of.

It seems to me that time is just a measure of the change and motion inherent to all physical processes in the same way that distance is just a measure of the spatial separation between objects or locations. Would you agree or disagree with that?

@budrap00

time is just a measure of the change and motion

(bold my addition) I could agree to that, except for the ‘just’ part because there has to be a reference clock.

Just as for 2 systems in motion (relative to a reference point) at the same velocity it appears to each one that the other is static, so too for two synchronised clocks it would appear if time is standing still - if everything else around them, and including themselves, is not changing. Is time standing still? No, this is an absurdity because in the cosmos there is always something changing.

Let’s stick to the analogy of two clocks at the top and at the foot of a mountain. We know that their clock rates differ. We know one system will look at the other and say: “time is passing slower for you” (and vice-versa faster for the other) which inherently means their measure of change and motion is not the same. This is not just an observation effect (of each other) because time does flow different for these two systems. They are each taking themselves as the reference and comparing the other.

The reference could also be something else, which may be the clock rate of cesium … in a vacuum … at 0’C … at sea level …. on earth. I probably missed something (voltage?) but wanted to show that a common reference could exist but labelling it ‘an exact measure of the cosmos clock’ would be absurd. Change one parameter and the clocks disagree.

Take this back to the observed redshift of distant galaxies. We could possibly explain this with the BB hypothesis that space is expanding. It has a certain logic to it, albeit flawed. We could also explain this with other methods that show a change of EMR happening over distance or time e.g. TL, apparently less flawed. BB and TL would be an observation effect, meaning distant systems are the same as our own but appear different here and now.

What is largely ignored is that the clocks of the ‘far away’ or ‘long ago’ (these are not the same concepts) systems are or were different to our own and therefore we are (for reasons yet unknown) the clock on top of the mountain and the distant galaxies are the clocks at the foot of the mountain. This would be a real difference - not just observed as with BB or TL. I’m not necessarily advocating for this - but pointing out as a plausible alternative which needs proper investigating as I think @mikehelland is doing.

What I am advocating for is that space is ticking the clocks of atoms. In my opinion we should investigate why space could be different ‘over there’ (a distance or location effect) or ‘back then’ (a time effect), or ‘changing between there and here’ or ‘changing between then and now’. My preference is uncertain. My tendency is toward that we are the clock on top of the mountain. How? Don’t know yet. My opening argument (against myself) would be that the distant system likely also thinks it is the clock on top of the mountain, and space is changing the signals in both (all) directions. Which is why I liked your expanding sphere concept.

@mikehelland writes: >I personally prefer Julian Barbour’s take on time, that change is primary and time is something we deduce from it. In other words, things don’t change in time; things change, and time is the result.

@RedshiftDrift writes: >the rate of change of an object is not the same as “time”.

@budrap00 writes: >It seems to me that time is just a measure of the change and motion

@Francois-Zinserling writes: >which inherently means their measure of change and motion is not the same

You are all making the same basic error here: Physics is part of our technology. Nothing of its “truth” can be considered as being independent of that technology, as it has been made up by us humans. When looking at nature, we are basically looking at ourselves as well. Time is OUR time. Especially take Orbital Time vs. Atomic Time.

Orbital clock

Repeated from a previous reply. Assuming a Circular orbit and Newtonian mechanics for an Orbital period $\Delta T$.

$$ m \omega^2 r = G\frac{m M}{r^2} \quad \Longrightarrow \quad \Delta T = 2\pi\sqrt{\frac{r^3}{GM}} $$

where $r=$ distance, $G=$ gravitational constant, $M=$ mass. With the Variable Mass theory the result is

$$ \frac{\Delta T}{\Delta T_0} = \sqrt{\frac{m_0}{m}} \quad \mbox{with} \quad M \rightarrow m $$

Atomic clock

Analogously, with Coulomb’s law instead of Newton’s law of gravitation, we calculate for an Atomic period $\Delta t$.

$$ m \omega^2 r = \frac{q^2}{4\pi\epsilon_0 r^2} \quad \Longrightarrow \quad \Delta t = 2\pi\sqrt{\frac{m.4\pi\epsilon_0 r^3}{q^2}} $$

where $q=$ charge, $\epsilon_0=$ electric constant. For the distance $r$ the Bohr radius is assumed:

$$ r = \frac{1}{\alpha}.\frac{\hbar}{m c} $$

where $\alpha=$ fine structure constant, $\hbar=$ reduced Planck constant, $c=$ speed of light. It follows that

$$ \Delta t = 2\pi\sqrt{\frac{m.4\pi\epsilon_0 \hbar^3}{\alpha^3 m^3 c^3 q^2}} = \mbox{constant} \times \sqrt{\frac{m}{m^3}} \sim \frac{1}{m} $$

And so

$$ \frac{\Delta t}{\Delta t_0} = \frac{m_0}{m} \qquad \mbox{contrary to} \qquad \frac{\Delta T}{\Delta T_0} = \sqrt{\frac{m_0}{m}} $$

With Variable Mass this means that free running Orbital clocks and Atomic clocks inevitably will go out of sync. Giving rise to the necessity of a Leap second. And VM can calculate for it:

$$ \mbox{number of leap seconds in a century} = \frac{(\mbox{ number of seconds in a century })^2}{\mbox{age of the earth in seconds}} $$

The presence of leap seconds implies technological activity by us humans, namely an act of synchronization at the infamous here and now timestamp, by putting $t=T=0$ and $\Delta T_0 = \Delta t_0$ . Take limits for $\Delta T \rightarrow dT$ and $\Delta t \rightarrow dt$ and find (again) that

$$ \frac{dT}{dt} = \sqrt{\frac{m}{m_0}} \quad \mbox{especially:} \quad \frac{dT}{dt}|_{t=0} = \sqrt{\frac{m_0}{m_0}} = 1 $$

Meaning that the two clocks - automatically or artificially ? - have equal ticks at the synchronization timestamp.

@budrap00 >I have no idea what that is supposed to mean

It means why expect mathematical approximations to be profound truths?

@budrap00 writes: >Redshift, time dilation, and a variable light speed are all correlated in a gravitational gradient.

As a humble mathemacist, I understand nothing of the above.

@HanDeBruijn >As a humble mathemacist, I understand nothing of the above.

Yes, of course, physics is not your strong suit, but still: in a gravitational gradient, there is a gravitational redshift correlated with position in the gradient. The same is true as well for time dilation and a varying light speed. Those are observed phenomena - they are facts.

Therefore all three phenomena are correlated in a gravitational gradient. What part of that are you having a problem processing?