Time is not simply what clocks measure. It is a force, a process, perhaps the most fundamental of all physical phenomena. What if the past has weight — and the future does too?
Rethinking Time
Time has always been difficult to define. Physicists can measure it, build equations around it, demonstrate how it slows near massive objects. But what it is — that escapes every formula.
Einstein taught us that time is not a universal constant. It passes more slowly in strong gravitational fields and at high velocities. In his spacetime geometry, everything moves at the speed of light through four-dimensional spacetime — with the share of movement through time decreasing the faster something moves through space. Time and space are not separate — they are two sides of the same fabric.
But perhaps time is even more than that. Perhaps it is not merely a dimension we move through — but a process that creates the universe in every moment.
Three States of Time
If you divide time into its three categories, a surprising picture emerges:
The Future — A Quantum State
The future does not exist as a fixed reality. It is a superposition of all possible states that the universe could assume in the next moment. In the language of quantum mechanics: a wave function of unimaginable complexity, simultaneously containing every conceivable configuration of particles, fields, and energies.
This is not a philosophical thought experiment — it is the foundation of quantum mechanics. Before a particle is measured, it exists in a superposition of all permitted states. Only measurement "selects" a state. The future is, on a cosmic scale, exactly that: Schrodinger's box, before it is opened.
The Past — Solidified Reality
The past is the opposite. It consists not of possibilities, but of facts. Every event that has occurred has irrevocably taken place. The positions of all particles, the interactions of all fields, the states of all systems — everything is fixed, frozen, irreversible.
The past is the counterpart of the future: Where the future is possibility, the past is certainty. Where the future is wave, the past is particle.
The Present — The Transformation Process
And the present? It is neither wave nor particle. It is the moment of transformation — the process in which the future becomes the past. The opening of Schrodinger's box. The decoherence that measures the quantum state and forces it into a definite outcome.
Physically speaking, the present does not "exist" as an independent state — it has already passed before we perceive it. It is a transition, not a place. A boundary between the possible and the settled.
"The present is the decoherence of the universe — the continuous collapse of a cosmic wave function, transforming future into past in every moment."
Information Has Weight
This is where it gets interesting — and where we leave well-established ground.
In 2019, physicist Melvin Vopson of the University of Portsmouth formulated the Mass-Energy-Information Equivalence Principle: an extension of Einstein's famous E=mc² by a third term — information.
The calculated mass of a single bit at room temperature is approximately 3.5 × 10⁻³⁸ kilograms — inconceivably small. But the universe does not contain one bit. It contains an amount of information that exceeds all human imagination.
Vopson's principle is not uncontested. Lairez (2024) and Burgin & Mikkilineni (2022) have raised objections, primarily concerning the distinction between the energy of information itself and the energy of the physical carrier. But the principle has a remarkable consequence if taken seriously.
Dark Matter — The Weight of the Past
Astronomers have known for decades that the universe exerts more gravitational force than visible matter can account for. Galaxies rotate too fast, galaxy clusters hold together more tightly than they should, and light from distant sources bends more strongly than expected. The explanation: dark matter — an invisible substance making up roughly 27% of the universe.
Despite decades of searching, no one has found a dark matter particle. The most sensitive detectors in the world, buried hundreds of meters underground, have registered nothing. Colliders like the LHC have produced no new particles beyond the Standard Model.
What if dark matter is not a particle — but the weight of history?
Imagine this: Every time two particles interact — collide, exchange a photon, become entangled — a piece of information is created. A record of the event, encoded in the quantum states of the participating particles. This information does not disappear. It persists as entangled quantum information, distributed across all particles that were involved in the event.
If information has mass, then every past event has added a tiny bit of weight to the universe. And this weight is not evenly distributed — it concentrates where a lot has happened. Where many particles have interacted. Where history is densest.
"Dark matter appears to be exactly where a lot of visible matter is." This is precisely what astronomers observe. And it is exactly what you would expect if the additional weight comes from the interaction history of matter.
Džaferović-Mašić formally investigated this idea in a 2021 paper, proposing "Missing Information in the Universe" as a dark matter candidate — based on Vopson's principle.
The weight of the past is not merely the sum of current states. It is the sum of all states that have ever existed — a cosmic memory whose burden curves spacetime.
"Gravity, as we know it, is the weight of the past. Dark energy is the weight of the future."
The two forces nearly balance each other — but not quite. Currently, the future still slightly outweighs the past. The tiny surplus on its side is what we observe as dark energy: a gentle but relentless accelerating expansion.
This would also explain why dark energy is so astonishingly small compared to the theoretically predicted vacuum energy. It is not small — it is a residual value after near-total compensation. Like the faint hum that remains when two nearly equal tones almost cancel each other out.
I want to emphasize: This is a speculative hypothesis. There is no mathematical proof and no experiment confirming this idea. But it offers an intuitive answer to one of the most pressing questions in modern physics.
The Big Bang — A Chain Reaction
If this picture holds, the Big Bang can also be understood differently.
Before the Big Bang: a singularity, a state of extreme density. The forces — the weight of the solidified past and the possibilities of the future — had long held each other in balance. An unstable equilibrium, like a pencil balancing on its tip.
Then the system reached a critical state. The energy density was so extreme that the number of possible subsequent states surged. Suddenly there was so much more future than past that the balance tipped.
The future "won" the tug of war — and tore space apart.
But the expansion did not only create space. It also created new possibilities: More space means more places where particles can exist, more possible configurations, more future. The expansion fed itself — a chain reaction that could explain the inflationary epoch: that fraction of a second in which the universe grew by a factor of 10²⁶.
The chain reaction ended when enough past had accumulated — enough realized states, enough interactions, enough weight — to nearly compensate the weight of the future once again. Since then, the universe has continued to expand gently, driven by the quiet surplus of possibilities.
Time Travel
This picture has another consequence — one that will disappoint science fiction fans.
Traveling into the future is possible. This is not speculation but experimentally confirmed physics. Move at a significant fraction of the speed of light, or stay near an extreme curvature of spacetime — such as a black hole — and time passes more slowly for you than for the rest of the universe. Astronauts on the ISS age measurably slower than people on Earth, albeit only by microseconds.
Traveling into the past is impossible. And not for technical reasons, but for logical ones: The past is solidified. All subsequent states — the entire future that emerged from a past moment — depend on the constancy of that moment. Changing the past would require the entire causal chain up to the present to be recalculated. This is not a technical problem — it is a logical contradiction.
If the present is the result of a specific past, and that past is altered, then the present from which the journey was undertaken no longer exists. The traveler cannot begin their journey because the future in which they exist is a different one.
"Should it somehow be possible to travel into the past, the first attempt would annihilate us."
The Hollywood Problem
And this brings us to what may be the most absurd assumption in science fiction: The idea that one could travel to the past and "just be careful." Do nothing conspicuous. Talk to no one. Just don't step on any butterflies.
This is complete nonsense — for a reason that chaos theory and quantum mechanics equally confirm.
Imagine someone travels to the year 1920 and does absolutely nothing remarkable. They walk down a street, step aside for a passerby, and in doing so kick a pebble to the side. That pebble now lies three centimeters further to the left. A beetle that would otherwise have crawled over it takes a different path. It is eaten by a bird that would not otherwise have found it. That bird survives the winter. Its offspring displace another bird species from a patch of woodland. The insect population in that forest shifts. A tree that would otherwise have been attacked by pests survives. Its shadow alters the microclimate of a field. A farmer's harvest turns out differently. The farmer makes a different decision, does not move to the city, marries a different woman.
After ten years, the entire demographic structure of a region has changed. After fifty years, different people have been born, different decisions made, different wars fought or not fought. After a hundred years, the world is entirely different — and none of it can be traced back to the time traveler who was "just going for a walk."
There are no harmless actions in the past. Every displaced atom, every redirected breath of air, every moment of eye contact with a stranger sets off a chain reaction whose effects over decades and centuries lead to a completely different present. This is not a dramatic device — it is physics.
A Final Thought
Time is the most self-evident thing in the world — and at the same time the most enigmatic. We experience it in every moment, yet we do not understand what it is. We measure it with atomic clocks to femtosecond precision, yet we cannot say why it flows in one direction.
Perhaps the answer lies in information. Perhaps the arrow of time is nothing other than the direction in which information is created — the direction in which possibilities become facts, in which waves collapse into particles, in which the future becomes the past.
And perhaps this process has a weight. One that we are already observing — without knowing that we are.