In 1929, Edwin Hubble discovered that the universe was expanding. However, this expansion today raises an enigma: The cosmos seems to expand more quickly near us than in more distant areas. Known as “Hubble tension”, this divergence confuses scientists and questions well -established theories.
While the data from the Planck satellite show a slower expansion of the primitive universeclose supernovae observations reveal a difference, close to 10 %, Sufficient to question the robustness of the current cosmological model. Are the measures wrong or a centerpiece of the theory lacking?
In July 2025, Researchers from the University of Portsmouth presented a bold solution, proposing that we live inside a “bubble” of low density. According to Dr. Indranil Banik, this would explain why the nearby galaxies move away faster than expected.
If this scenario is real, there is no error in the data, but in the way of observing, it would be like being in a valley surrounded by hills and our position, everything would seem more inclined than it is in reality, so we would need a change of perspective difficult to achieve since our location in the galaxy.
Big Bang Echoes
To verify this hypothesis, cosmologists have used what is called the acoustic oscillations of bariums (BAO), Big bang echoes preserved in the material of the universe, a kind of undulation which works as a cosmic rule, allowing us to measure the distances and structures with precision, thus revealing the deep structure of the cosmos.
BAOs show that matter is not uniformly distributed over large scales, Because there are fewer galaxies than expected in our environment, which corroborates the existence of a local vacuum. Recent data indicate that this model is 100 million times more likely than the traditional model.
The severity of the external regions draws the material to the outside, accelerating its movement, a flow that increases the red shift from the nearby galaxies, simulating an accelerated expansion. Thus, the apparent contradiction between local and distant measures finds a coherent bridge.
If it were confirmed, this hypothesis would not only resolve Hubble’s tension, but would reopen an old dilemma: do we occupy a “special” area in the cosmos? A question that science has been eluded since the Copernican revolution, which has taught us that we are at the center of nothing.
Empty giants: the limits of current physics
A gap of a billion light-of-the-ray calls into question the cosmological principle, which postulates that the universe is homogeneous on a large scale. If it is verified, the λcdm model, which is the basis of current cosmology, must be adjusted to integrate this unexpected asymmetry.
The λCDM model, also called standard cosmological model, is the most widely accepted description of the evolution and structure of the universe. It incorporates black energy (represented by Lambda, λ) and cold dark matter (CDM).
Some experts claim that structures of such magnitude are unlikely according to the simulations of dark matter. In the near future, telescopes such as Euclid and Vera Rubin could provide evidence, by mapping the distribution of galaxies with an unprecedented level of detail.
Meanwhile, other theories are strengthened and the idea of early black energy suggests that an unknown force has changed the expansion of the universe When he was still in his early days. However, the local vacuum is distinguished by the simplicity with which it adapts to data without adding complex variables.
This debate reflects a fundamental principle of science: any theory must adjust to evidence. In the same way that Copernicus upset our vision of the solar system, The existence of a cosmic bubble could open a new chapter in the history of modern cosmology.
Look to the future: Future questions and results
To confirm this theory, Astronomers plan to compare the emptiness model with what are called cosmic clocks, That is to say old galaxies whose age is deducted from the absence of young stars; If their age corresponds to the predictions, the void will be solidly supported.
Large -scale material flows constitute another crucial index, because if we live in the void, a massive displacement of galaxies to the edges of this bubble should be observed, And this is where projects such as LSST in Chile could detect these movements towards the end of this decade.
Beyond abstraction, Understanding the expansion of the universe has practical consequences, Because knowing whether the cosmos will go out forever or will collapse redefine theories, inspires new technologies and raises philosophical dilemmas as to our role in immensity.
In this discovery trip, each discovery reminds us that the greatest certainty is our ignorance and that perhaps, as in the time of Galileo, we are close to seeing reality with a renewed look, pushing the limits of the visible and the possible.