A newly derived “q-desic” equation suggests that quantum effects may subtly alter particle trajectories across the universe.
Bringing together quantum physics and gravity is often described as the “Holy Grail” of modern science. Quantum theory explains the behavior of the smallest particles with remarkable precision, while Einstein’s general theory of relativity describes gravity and the large-scale structure of the universe. Yet despite decades of effort, these two foundational frameworks still cannot be fully reconciled.
A variety of proposals attempt to bridge this divide, including string theory, loop quantum gravity, canonical quantum gravity, and asymptotically safe gravity. Each approach offers promising ideas but also faces unresolved problems.
One major obstacle has been the lack of clear experimental predictions. Without measurable quantities to compare against observations, it remains impossible to determine which theory, if any, correctly describes nature. Researchers at TU Wien now report progress that could help move the field closer to that goal.
Cinderella and quantum gravity
“It’s a bit like the Cinderella fairy tale,” says Benjamin Koch from the Institute for Theoretical Physics at TU Wien. “There are several candidates, but only one of them can be the princess we are looking for. Only when the prince finds the slipper can he identify the real Cinderella. In quantum gravity, we have unfortunately not yet found such a slipper – an observable that clearly tells us which theory is the right one.”
To identify this missing “slipper,” meaning a measurable test that could distinguish between competing theories, the team focused on a central concept in relativity known as a geodesic. “Practically everything we know about general relativity relies on the interpretation of geodesics,” explains Benjamin Koch.
“A geodesic is the shortest connection between two points – on a flat plane, that’s simply a straight line, whereas on curved surfaces things become more complicated.” For example, if you want to move from the North Pole to the South Pole on the surface of a sphere, the shortest path is a semicircle.
In Einstein’s theory, space and time form a unified four-dimensional structure called spacetime. Massive objects such as stars and planets bend this spacetime. According to general relativity, Earth revolves around the Sun because the Sun’s mass curves spacetime, shaping the path Earth follows into an almost circular orbit.
The quantum version of geodesics
The shape of these paths depends on what physicists call the metric, which describes how strongly spacetime is curved. “We can now try to apply the rules of quantum physics to this metric,” says Benjamin Koch. “In quantum physics, particles have neither a precisely defined position nor a precisely defined momentum. Instead, both are described by probability distributions. The more precisely you know one of them, the more fuzzy and uncertain the other becomes.”
In quantum mechanics, quantities such as position and momentum are represented by wave functions rather than exact values. Using a similar strategy, researchers can attempt to treat the spacetime metric itself as a quantum object. In that case, curvature would no longer have a single well-defined value at each point. Instead, it would fluctuate according to quantum rules.
This approach leads to major mathematical challenges.
Working with his PhD student Ali Riahinia and Angel Rincón (Czech Republic), Koch developed a new method for quantizing the metric in a specific but important situation: a spherically symmetric gravitational field that remains constant over time.
This type of gravitational field can describe the Sun’s gravity. “Next, we wanted to calculate how a small object behaves in this gravitational field – but using the quantum version of this metric,” says Koch. “In doing so, we realized that one has to be very careful – for instance, whether one is allowed to replace the metric operator by its expectation value, a kind of quantum average of the spacetime curvature. We were able to answer this question mathematically.”
Their work led to a new equation, which the researchers call the q-desic equation, referring to the classical idea of geodesics. “This equation shows that in a quantum spacetime, particles do not always move exactly along the shortest path between two points, as the classical geodesic equation would predict.” In principle, precise observations of freely moving objects in spacetime, such as an apple falling toward Earth in outer space, could reveal information about the quantum nature of spacetime itself.
Shoe size 10-35 or rather 10+21?
How different is a q-desic from an ordinary geodesic? When considering gravity alone, which is the weakest of the known fundamental forces, the difference is extraordinarily small. “In this case, we end up with deviations of only about 10-35 meters (about 1 × 10-33 inches) – far too small to ever be observed in any experiment,” says Benjamin Koch.
However, general relativity also includes the cosmological constant, often associated with “dark energy.” This quantity drives the accelerating expansion of the universe on the largest scales. When the team incorporated the cosmological constant into the q-desic equation, the outcome changed dramatically.
“And when we did that, we were in for a surprise,” reports Benjamin Koch. “The q-desics now differ significantly from the geodesics one would obtain in the usual way without quantum physics.”
The deviations appear at both extremely small and extremely large distances. Although the tiny-scale differences are unlikely to be measurable, the situation is different at vast cosmic scales. At distances of around 1021 meters (about 6.2 × 1020 miles), the predicted paths can diverge substantially. “In between, for example when it comes to the Earth’s orbit around the Sun, there is practically no difference. But on very large cosmological scales – precisely where major puzzles of general relativity remain unsolved – there is a clear difference between the particle trajectories predicted by the q-desic equation and those obtained from unquantized general relativity,” says Benjamin Koch.
A new perspective on observational data
The findings, published in the journal Physical Review D, introduce more than a new mathematical framework for connecting quantum theory and gravity. They also suggest a possible path toward testing quantum gravity using astronomical observations.
“At first, I would not have expected quantum corrections on large scales to produce such dramatic changes,” says Benjamin Koch. “We now need to analyze this in more detail, of course, but it gives us hope that by further developing this approach we can gain a new, and observationally well testable, insight into important cosmic phenomena – such as the still unsolved puzzle of the rotation speeds of spiral galaxies.”
Returning to the Cinderella analogy, researchers may finally have identified a potential observable that can separate promising quantum gravity theories from those that fall short. A slipper has been found – now we have to find out which theory it truly fits.
Reference: “Geodesics in quantum gravity” by Benjamin Koch, Ali Riahinia and Angel Rincon, 22 October 2025, Physical Review D.
DOI: 10.1103/w1sd-v69d
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9 Comments
Quantum mechanics is 10-base number geometry – artificial lines – an off-ramp from reality. Gee, we love math.
The whole while, our minds are akin to neural-net super computers –
Ponto lake
A slipper has been found – now we have to find out which theory it truly fits.
VERY GOOD!
If we cease asking “whether observation disturbs the object” and instead ask “how observation participates in the topological variation of the object,” our understanding of scientific knowledge may enter a new realm.
—— Excerpted from https://zhuanlan.zhihu.com/p/2010973729556026200.
Except “observation” doesn’t appear anywhere in the quantum formalism. It’s just handwaving.
Thank you for browsing and commenting. I have a windmill in my hand, and it is rotating (right now). Can you tell me if it is rotating clockwise or counterclockwise? If you observe it, do you see clockwise or counterclockwise rotation? Why?
When we pursue the ultimate truth of all things, the space in which our bodies and all things exist may itself be the final and deepest puzzle we need to explore. This is not only the pursuit of physics, but also the most magnificent exploration of the origin of the universe by human reason.
Based on the Topological Vortex Theory (TVT), space is an uniformly incompressible physical entity. Space-time vortices are the products of topological phase transitions of the tipping points in space, are the point defects in spacetime. Point defects do not only impact the thermodynamic properties, but are also central to kinetic processes. They create all things and shape the world through spin and self-organization.
In today’s physics, some so-called peer-reviewed journals—including Physical Review Letters, Nature, Science, and others—stubbornly insist on and promote the following:
1. Even though θ and τ particles exhibit differences in experiments, physics can claim they are the same particle. This is science.
2. Even though topological vortices and antivortices have identical structures and opposite rotational directions, physics can define their structures and directions as entirely different. This is science.
3. Even though two sets of cobalt-60 rotate in opposite directions and experiments reveal asymmetry, physics can still define them as mirror images of each other. This is science.
4. Even though vortex structures are ubiquitous—from cosmic accretion disks to particle spins—physics must insist that vortex structures do not exist and require verification. Only the particles that like God, Demonic, or Angelic are the most fundamental structures of the universe. This is science.
5. Even though everything occupies space and maintains its existence in time, physics must still debate and insist on whether space exists and whether time is a figment of the human mind. This is science.
6. Even though space, with its non-stick, incompressible, and isotropic characteristics, provides a solid foundation for the development of physics, physics must still insist that the ideal fluid properties of space do not exist. This is science.
and go on.
Is this the counterintuitive science they widely promote? Compromising with pseudo academic publications and peer review by pseudo scholars is an insult to science and public intelligence. Some so-called scholars no longer understand what shame is. The study of Topological Vortex Theory (TVT) reminds us that the most profound problems in physics often lie at the intersection of different theories. By exploring these border regions, we can not only resolve contradictions in existing theories but also discover new physical phenomena and application possibilities.
Under the topological vortex architecture, it is highly challenging for even two hydrogen atoms or two quarks to be perfectly symmetrical, let alone counter-rotating two sets of cobalt-60. Contemporary physics and so-called peer-reviewed publications (including Physical Review Letters, Science, Nature, etc.) stubbornly believe that two sets of counter rotating cobalt-60 are two mirror images of each other, constructing a more shocking pseudoscientific theoretical framework in the history of science than the “geocentric model”. This pseudo scientific framework and system have seriously hindered scientific progress and social development.
For nearly a century, physics has been manipulated by this pseudo scientific theoretical system and the interest groups behind it, wasting a lot of manpower, funds, and time. A large amount of pseudo scientific research has been conducted, and countless pseudo scientific papers have been published, causing serious negative impacts on scientific and social progress, as well as humanistic development.
Complexity does not necessarily mean that there is no logical and architectural framework to follow. Mathematics is the language and tool that reveals the motion of spacetime, rather than the motion itself. Although the physical form of spacetime vortices is extremely simple, their interaction patterns are highly complex, and we must develop more and richer mathematical languages to describe and understand them.
The development of the Topological Vortex Theory (TVT) reflects a progression from concrete physical phenomena to abstract mathematical modeling and, ultimately, to interdisciplinary unification. Its core innovation lies in forging the continuous spacetime geometry of general relativity with the discrete interactions of quantum field theory within the same topological dynamical system. The core idea of TVT — space is physical, and matter is its topological excitation—already provides a solid and elegant scientific path for understanding the origin of all things.
——Excerpted from https://scitechdaily.com/microscope-spacecrafts-most-precise-test-of-key-component-of-the-theory-of-general-relativity/#comment-909171 and https://t.pineal.cn/blogs/6255/A-Mathematical-and-Physical-Analysis-On-the-Origin-of-Objects.
Are these science?
Example 1
Two sets of cobalt-60 are manually rotated in opposite directions, and even without detection, people around the world know that they will not be symmetrical because these two objects are not mirror images of each other at all. However, a group of so-called physicists and so-called academic publications do not believe it. They conducted experiments and the results were indeed asymmetric, but they still firmly believed that these two objects were mirror images of each other, and the asymmetry was due to a violation of the previous natural laws (CP violation). In the history of science, there can never be a dirtier and uglier operation and explanation than this.
—— Excerpted from https://scitechdaily.com/what-happens-when-light-gains-extra-dimensions/#comment-947619.
Example 2
Please see how the so-called “mystery of θ – τ” is explained: θ and τ are completely identical in all measurable physical properties such as mass, lifetime, charge, spin, etc. However, experimental observations have shown that the θ meson decays into two π mesons, while the τ meson decays into three π mesons, making it difficult for physicists to explain why they are so similar. Physicist Martin Block proposed a highly challenging idea: θ and τ are the same particle, but in weak interactions, parity is not conserved. An easy to understand explanation is the following analogy:: There are two boxes of apples with identical weight, color, and taste. However, when one box is opened, there are two apples, while when the other box is opened, there are three apples. This confuses the old farmer who buys apples. He circled around the orchard and came up with a highly challenging idea: these two boxes of apples are not from the same tree, so they are the same.
—— Excerpted from https://scitechdaily.com/what-happens-when-light-gains-extra-dimensions/#comment-947686.
Everyone who has a reverence for natural laws and regulations deserves respect.
In the physical world constructed by the American Physical Society (APS) and its publications using parity violation, particles from God, Demons, and Angels wander around, while dead and alive cats jump up and down, unconstrained by dynamics and thermodynamics, and unaware of what is dirty, ugly, and shameful in public. APS and its publications reject the possibility that spaces with zero viscosity, zero compression, and zero anisotropy in mathematics may form spatiotemporal vortices through topological transformations. They don’t know that space and non existence are not the same concept.
If a self proclaimed scientific society (such as American Physical Society) deviates from science without shame, it is highly likely to be heading towards the end.
This is what happens when you canonise a mathematical model and then try to warp reality to fit it.
I like it
I’ve been developing an independent theoretical framework in my own time — just for the love of the idea honestly. Put it on Zenodo this week. It hits on this from a differ angle, really cool love it. Sharing here in case it connects with anyone thinking about similar things.
https://zenodo.org/records/18870167
If light is composed of particle that don’t get to us in straight lines on the scale of the universe ,what comes next?