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Hubble tension

The Hubble tension—it’s that annoying crack in the universe’s story that nobody can seem to patch up. Some say the universe is expanding slower (CMB), some say it’s expanding faster (local measurements using Cepheids and supernovae). It’s the same fight over and over, different tools, same sky, but what if both sides are kind of right, and yet, completely missing the bigger picture?

Let’s just say, for a moment, that light speed isn’t this holy, constant grail we think it is. It’s relative. Variable. Not in some abstract, mind-bending sense, but actually, literally fluctuating as it moves through the crumpled mess of space-time. This isn’t just a wild theory; we’re treating light speed like it’s the same everywhere, but only because, from where we sit, everything looks the same above a certain threshold. So we slap the term *light speed" on it and call it a day.

Light speed, as we so confidently define it, is a universal constant—until it isn't. The very idea that light moves at a fixed speed across the entirety of space-time is a simplification. It is useful, yes, but profoundly misleading when we begin to probe deeper into the universe's structure, specifically into the Hubble tension. This ongoing discrepancy between the universe’s expansion rate based on CMB measurements (around 67-68 km/s/Mpc) and local distance ladder methods (which show a higher rate of around 73-74 km/s/Mpc) is more than a mere anomaly. It is a signal that our current framework may be flawed.

To those of us exploring more nuanced interpretations, the crumpling of space-time—the crumpled aether theory—provides a lens through which to reconsider the behavior of light. We speak of light speed as if it is an unwavering constant, but it is relative, subject to the distortions of space-time. We reach a point where the differences in speed are imperceptible, and thus we assign the label “light speed” as if it were immutable. But what if, as the theory suggests, light’s speed varies subtly as it moves through different regions of a space over time that is anything but smooth?

Cepheid variables—those pulsating stars that we rely on to establish cosmic distances—are part of this complexity. Their relationship between luminosity and pulsation gives us a way to measure distances, forming the backbone of the local distance ladder. Yet, we use them under the assumption that light behaves uniformly across space. If the aether is crumpled, if light speed fluctuates across regions, then the distances we measure using Cepheids are distorted. Type Ia supernovae, which we use in conjunction with Cepheids, would similarly be affected, further complicating our local measurement of the Hubble constant.

Now, contrast this with the CMB, which provides a snapshot of the early universe. The universe then was smoother, less structured. Light traveled through a less crumpled space-time, which means that the measurements derived from the CMB are fundamentally different from what we observe in the present universe. Our current universe, with its galactic structures and voids, has regions where space-time behaves differently—crumpled, as it were—causing light to interact in variable ways depending on where it travels.

So now, its not so simple. You need to consider when you throw in Cepheid variables and their pals, the Type Ia supernovae. They’re the cosmic rulers we use to measure distances in our local neighborhood. It’s neat, precise—until it’s not. Because if light’s speed is varying based on where it travels, then these standard candles we so heavily rely on are giving us skewed results. Maybe that explains why we see one expansion rate locally, but when we zoom out to the CMB, the whole thing slows down. We’ve been assuming the universe is this smooth, continuous sheet, but in reality, it’s more like a crumpled piece of paper that’s been thrown into some cosmic corner.

In the early universe, everything was simpler, less structure, fewer wrinkles. CMB data reflects that pristine time, when light had a straight shot through relatively smooth space-time. But as the universe grew, the wrinkles started forming—galaxies, voids, clusters, all crumpling space-time in different ways. Light had to start navigating these bumps, slowing down in some places, speeding up in others, which means the way we measure redshift and the expansion rate today is fundamentally different from how we measure it in the early universe.

Think about it. Local measurements like Cepheids and supernovae are happening in a universe that’s way more crumpled, way more complex. It’s like trying to measure how fast your car is going on a twisty, bumpy road versus an open highway. You’re bound to get different readings. But instead of questioning the road, we’ve been blaming the tools. The real issue might just be the assumption that space-time is smooth and light behaves the same everywhere. Spoiler alert: it doesn’t.

And here’s where things start to get spicy. If light speed is variable, then maybe redshift—that golden standard for measuring cosmic distances—needs a second look. We’ve been treating it like it’s a straightforward function of the universe’s expansion, but what if part of that redshift is due to the light interacting with space-time in different ways depending on how crumpled it is? Maybe the expansion rate we’re measuring isn’t just about galaxies moving away from each other but also about how space-time itself is shaping light’s journey.

Void-like regions, the big empty expanses between galaxy clusters, could actually be less crumpled, allowing light to move a little faster, creating a lower redshift than we’d expect. Dense, structure-rich regions? That’s where light might slow down, bending, twisting, taking detours. This would explain why we see different expansion rates depending on where we look. It’s not that the universe is lying to us; it’s that we’ve been looking at a tangled, crumpled map and pretending it’s a clean one.

This crumpled aether model gives us a way to reconcile the Hubble tension without having to reinvent the cosmic wheel. It’s not that the CMB measurements are wrong or that local Cepheid measurements are wrong. They’re just telling different sides of the same story. A universe that isn’t expanding uniformly because the stage it’s performing on isn’t uniform.

What we need to do now is dig deeper. Test this hypothesis. Recalibrate the distance ladder using the idea that light speed isn’t a constant, that space-time isn’t smooth. Gravitational lensing could be the key—if light’s path bends more in crumpled regions, we’d expect some weird anomalies in time delays, in how we see lensed galaxies. And that’s testable.

So maybe the universe isn’t this pristine, perfectly stretched canvas. Maybe it’s a crumpled piece of cosmic paper, tossed into a corner of space, full of folds and twists that make light’s journey a little more complex than we’ve been willing to admit. Maybe the Hubble tension is just the first tear in that paper, a signal that it’s time to rethink what we thought we knew about the fabric of space & time.

Topic: Hubble tension, particularly around hypotheses like the under-density bubble and how it relates to the cosmic expansion rate.

The Hubble tension refers to the discrepancy between two methods of measuring the universe’s expansion rate, known as the Hubble constant (H₀). This value is critical because it tells us how fast the universe is expanding. However, the tension arises because different methods of measurement give us different values for H₀, leading scientists to question whether our understanding of cosmology needs revision.

(it does)

Let’s break this down in detail:

Two Key Measurement Methods of H₀:

  1. Cosmic Microwave Background (CMB) Data: The CMB is the afterglow from the Big Bang and reflects conditions of the early universe. Data from satellites like Planck provide highly precise measurements of this radiation. Using a model (Lambda-CDM), scientists extrapolate the Hubble constant by interpreting the geometry of space-time and the distribution of matter in the early universe. These measurements yield a value of H₀ ~ 67-68 km/s/Mpc​(ar5iv).

  2. Local Universe Measurements (Distance Ladder): This method involves Cepheid variables and Type Ia supernovae. Cepheids are pulsating stars with a well-established relationship between their luminosity and pulsation period. Astronomers measure their brightness and, using their known distances, can build a "distance ladder" to determine the expansion rate in the local universe. This method gives a higher value of H₀ ~ 73-74 km/s/Mpc​(ar5iv)​(ar5iv).

The state of the art says Hubble tension arises from discrepancies in the universe's expansion rate as measured using early universe data (Cosmic Microwave Background - CMB) versus local universe observations. A delve into the discrepancies in the Hubble constant (H0), focusing on the latest measurements from CMB (Planck data) and local distance-ladder methods like Type Ia supernovae and Cepheid variables. Studies suggest that local effects, such as the under-density hypothesis, may explain these differences without invoking new physics, like dark energy​(ar5iv)​(ar5iv).

Cepheid Variables are used in the local universe as a standard candle because their intrinsic brightness can be calculated based on their pulsation. By comparing their intrinsic brightness to how bright they appear from Earth, astronomers can calculate their distance.

  1. This distance measurement is crucial because it helps establish the Hubble flow—the relationship between distance and velocity for galaxies. As galaxies move away, the redshift of light from them increases. This redshift is used to calculate H₀ locally.

  2. However, the Cepheid-based measurement of H₀ (in the local universe) is consistently higher than the CMB-based H₀. This discrepancy is a core part of the Hubble tension​(ar5iv).

Light speed (c) is central to measuring distances in cosmology because both the redshift and the time light takes to travel from distant objects are involved in calculations of H₀.

  1. In the standard model, the speed of light is considered constant in a vacuum. However, if your theory of crumpled aether or variable light-speed comes into play, it could affect redshift calculations and thereby alter the perceived distance or velocity of objects. If light speed varies slightly across different regions of the universe due to space-time anomalies, this would lead to differences in how we measure distances, thus affecting the H₀ value.

  2. For example, in a universe where light speed is not uniform, galaxies could appear to move away at faster rates or farther distances depending on the local conditions of space-time. This variability would create discrepancies in how we measure H₀ locally (using Cepheids and supernovae) versus from the CMB, which relies on early-universe conditions​(ar5iv).

The Crux of the Hubble Tension:

  • CMB measurements come from an era about 380,000 years after the Big Bang, when the universe was much younger and simpler (matter was more uniformly distributed).

  • Local measurements from Cepheids and supernovae, however, reflect the current universe, which is much more complex and inhomogeneous due to structures like galaxies and dark matter.

  • If your crumpled aether theory holds, it suggests that space-time is more varied than assumed in current models. This variability might explain why local measurements of H₀ are higher: the expansion rate could appear faster in regions of "crumpled" space-time, while early-universe measurements, which assume uniform conditions, show a slower expansion​(ar5iv)​(ar5iv).

A significant avenue of research is the role of ‘relativistic dark matter’ (notice the quote marks) and its interaction with neutrinos, which could explain discrepancies in the measured expansion rate of the universe. One promising theory suggests that early-universe dark matter production might be key to resolving the tension between local measurements and cosmic microwave background (CMB) estimates【33†source】【34†source】

Furthermore, recent research has used cutting-edge tools like the James Webb Space Telescope to refine the cosmic distance ladder, ruling out certain errors in measuring Cepheid variables and solidifying the existence of the Hubble tension【35†source】

This reinforces the hypothesis that local conditions, such as under-density in our region of space, might affect expansion rates without needing dark energy【33†source】【36†source】

My thought is with effective field theories that model these relativistic particles, especially scalar dark matter, which could offer new perspectives on early universe phenomena….that is by comparing current findings with my existing theories on localized space-time anomalies, maybe we can build a cohesive narrative around these modern discoveries.

However—our certainty about cosmological models, like the Big Bang, is largely based on assumptions, interpretations of data, and mathematical frameworks that themselves evolve over time. The idea that the universe began in a singular Big Bang has dominated cosmology, but alternative theories—like the Big Bounce, steady-state models, or some combination (that obviously must include the crumpled aether concept ;) and as such—open up intriguing possibilities.

The Big Bang posits a singular point from which all space, time, and matter expanded, but it faces philosophical and scientific challenges, such as what came "before" the Big Bang and how it avoids an infinite density point.

The Big Bounce is an alternative that suggests the universe may have expanded, contracted, and then "bounced" back into expansion again, perhaps in a cyclical manner. This resonates with the crumpled aether metaphor: rather than a clean explosion, imagine a universe with cycles of contraction and expansion, like a crumpled piece of paper that periodically unfolds and refolds​(ar5iv)​(ar5iv).

I propose a recalibration of cosmological models that incorporates a variable light-speed based on the crumpling of space-time. This framework could bridge the gap between CMB data and local measurements by introducing spatial variability in the expansion rate and redshift. It would require further observational tests, specifically around gravitational lensing, Cepheid redshift calibration, and cosmic voids, to validate.

If this model holds, we would shift from seeing the universe as a uniform expanse to a more dynamically structured entity

In this analogy, each contraction phase causes the universe to crumple further, creating more dense structures like black holes, neutron stars, or even regions of highly warped space-time. Black holes, in particular, might represent areas where this crumpling reaches an extreme—essentially folds in the universe that collapse in on themselves. As the universe breathes out during expansion, the crumples might partially smooth out, but never entirely. This could explain why space-time, at its deepest levels, feels so textured and complex.

Over multiple cycles of bouncing, this crumpling becomes more predictable but still chaotic—each "breath" of the universe leaving a new configuration of black holes, galaxies, and space-time distortions in its wake. The universe isn’t a clean expansion from a singularity, but an intricate, chaotic dance of contractions and expansions, folding in on itself in unpredictable ways, much like the collapse and formation of supermassive black holes at the centers of galaxies.

Black holes could be seen as anchors of this crumpling process. As the universe contracts, matter and energy get funneled into these dense pockets, effectively causing the most intense forms of crumpling. During expansion, some of this energy may escape, but black holes remain as vestiges of the last contraction, holding the deepest scars of space-time’s folding.

Our lung analogy fits here—inhale, exhale, and yet the crumples from the previous breath remain, marked in the structure of black holes and the fabric of space-time. These crumples, black holes, and space-time anomalies might hold the memory of previous universes, making each bounce distinct while carrying the same fundamental patterns.

Over time, the universe could be settling into natural rhythms. Each expansion and contraction cycle may not be perfectly uniform, but they could be approaching some form of equilibrium, where the crumpling becomes a repeated, predictable pattern. Black holes might form at regular intervals, galaxies cluster in similar ways, and the very expansion of the universe could find a steady rhythm as it bounces in and out of these states.

In this way, the universe might resemble a breathing entity, adjusting to its cycles, much like a lung finding a natural breathing pattern over time. Each contraction pulls in more structure, forms more crumples, and builds more complex entities like black holes, while each expansion tries to smooth things out, but never completely.

This idea suggests that the universe is far from a static or one-time event like the Big Bang. Instead, it’s an evolving, breathing system, expanding and contracting, crumpling and smoothing out. Over time, black holes and other dense structures act as markers of these cycles, creating a natural, recurring pattern of space-time’s evolution. The Big Bounce, in this sense, is not just a theory about how the universe expands, but also how it ages, breathes, and forms through cycles of creation and destruction. The universe crumples into itself like a lung, adapting and settling into a rhythm over an eternity of bounces.