The universe is full of mysteries, but two of the biggest are dark matter and dark energy. Scientists believe these two invisible things make up about 95% of the entire universe, yet no one knows exactly what they are.
Dark matter cannot be seen, but its gravity helps hold galaxies together. Dark energy is even stranger. It is believed to be the force that is making the universe expand faster and faster.
For many years, scientists have studied dark matter and dark energy as two separate mysteries. But now, a new study by Pereira and his team suggests something exciting. They believe that both dark matter and dark energy may come from gravity itself. If this idea is correct, it could completely change how we understand the universe.
What Is Dark Matter?
Everything we can see—stars, planets, galaxies, gas, dust, and even people—makes up only about 5% of the universe.
The remaining 95% is invisible. Around 27% is thought to be dark matter, while about 68% is dark energy.
Dark matter does not produce or reflect light, so telescopes cannot see it directly. Scientists know it exists because of its gravity.
For example, galaxies spin much faster than they should. If only visible matter were present, many galaxies would fly apart. Something invisible is providing extra gravity to keep them together. Scientists call this invisible material dark matter.
Even today, researchers do not know what dark matter is made of.
What Is Dark Energy?
Dark energy is even more mysterious.
In 1998, astronomers discovered that the universe is not only expanding but expanding faster over time. Something is pushing galaxies farther apart.
Scientists named this unknown force dark energy.
The simplest explanation is something called the cosmological constant, which means dark energy stays the same forever.
However, recent observations suggest that dark energy may not be constant. Instead, it may slowly change as the universe grows older.
This has encouraged scientists to search for new explanations.
A New Idea
Pereira and his team wanted to answer an important question.
Could dark matter and dark energy actually come from the same source?
Instead of treating them as two different things, they looked at whether both could naturally appear from a special theory of gravity.
This idea is very different from most existing theories.
A Different Way to Think About Gravity
The researchers used a theory called No-Scale Gravity.
Einstein's theory of gravity uses an important number called the Planck scale, which helps describe how strong gravity is.
But No-Scale Gravity suggests something surprising.
It says the Planck scale may not be a basic property of nature. Instead, it may only appear because of how the universe behaves.
In other words, gravity may work in a much deeper and simpler way than scientists once thought.
This new theory removes built-in mass scales and follows a property called scale invariance, meaning the basic laws stay the same even if the size of things changes.
Because of this, No-Scale Gravity gives scientists a new way to explain the universe.
A Special Field in Gravity
In this theory, there is a special field known as the Brans–Dicke field.
You can think of a field as something that fills all of space.
Earlier studies showed that this field might help explain dark energy.
Now, Pereira's team has expanded this idea.
Instead of using only one field, they added two more similar fields.
Together, these three fields work as one system.
This is where the exciting part begins.
One System Creates Two Mysteries
The three fields are connected through a mathematical symmetry called O(3).
Although the mathematics is complex, the basic idea is simple.
Imagine a perfectly round ball.
Every direction on the ball looks exactly the same.
Now imagine making tiny changes to that perfect shape.
Suddenly, different directions begin acting differently.
According to the researchers, something similar happens in their model.
One direction behaves like dark matter, while another behaves like dark energy.
This means both could be different parts of the same gravitational system.
Instead of being completely separate, they may have a common origin.
Tiny Changes Make a Big Difference
The perfect symmetry does not stay perfect forever.
The researchers added very small changes to the system.
These tiny changes give the two fields different properties.
One field becomes dark matter.
The other becomes dark energy.
The same small changes also allow the two fields to interact with each other.
This is important because many earlier models simply assumed dark matter and dark energy already existed.
In this new theory, both appear naturally from gravity.
Can Dark Matter and Dark Energy Affect Each Other?
Most current models assume dark matter and dark energy do not directly interact.
But this new theory suggests they can.
Since both come from the same gravitational system, they can exchange energy as the universe evolves.
This interaction changes how the universe expands over billions of years.
It also helps explain several observations that have puzzled scientists.
Matching the Real Universe
A new theory must agree with real observations.
The researchers tested their model to see whether it could reproduce the known history of the universe.
Their calculations showed that it successfully produces:
the correct amount of dark matter,
the correct amount of dark energy,
and the observed expansion of the universe.
As time passes, the lighter field naturally begins to dominate, causing the accelerated expansion that astronomers observe today.
This is one of the strongest results of the study.
What Did DESI Discover?
One of the world's biggest space surveys is the Dark Energy Spectroscopic Instrument (DESI).
DESI studies millions of galaxies to understand how the universe has expanded over time.
Recent DESI observations suggest that dark energy might not be completely constant.
Instead, it may slowly change as the universe ages.
Although scientists still need more evidence, these results have attracted a lot of attention.
Interestingly, Pereira's new model naturally allows dark energy to change over time.
This makes the theory even more exciting.
A Strange Expansion Without Strange Physics
Scientists describe dark energy using a number called w.
If w = -1, dark energy behaves like the cosmological constant.
Some observations suggest that w might even become smaller than -1.
This is called phantom-like behavior.
Normally, explaining this requires unusual particles that create serious problems in physics.
The new theory avoids this problem.
Instead of introducing strange particles, the interaction between dark matter and dark energy makes the universe behave as if w is below -1.
In other words, the universe looks like it has phantom dark energy, even though it actually does not.
A Very Light Form of Dark Matter
The researchers also suggest that dark matter may be made of extremely light particles.
This type of dark matter is called ultralight dark matter.
Scientists are becoming increasingly interested in this idea because it may solve some problems found in older dark matter models.
Future observations may help determine whether this prediction is correct.
Why Is This Study Important?
The biggest strength of this research is that it brings together two of the greatest mysteries in science.
Instead of creating one theory for dark matter and another for dark energy, the researchers explain both using a single theory of gravity.
Their model also explains why the two invisible components may interact with each other.
Everything comes from the same underlying gravitational system.
This makes the theory much simpler and more elegant than many previous ideas.
What Happens Next?
This research is still a theoretical proposal. It has not yet been proven by experiments or observations.
In the coming years, powerful telescopes and space missions will collect more accurate data about the universe.
Scientists will compare those observations with the predictions made by this new model.
If future evidence supports the theory, it could become one of the biggest breakthroughs in modern cosmology.
For now, the study gives scientists an exciting new way to think about the invisible universe. It suggests that dark matter, dark energy, and even the connection between them may all come from gravity itself, bringing us one step closer to understanding what most of the universe is really made of.
Reference: Lincoln da S. Pereira, Muzi Hong, Elisa G. M. Ferreira, Tsutomu T. Yanagida, "Interacting Dark Energy and Dark Matter in O(3) No-Scale Gravity", Arxiv, 2026. https://arxiv.org/abs/2607.20320
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