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Dark Matter and Dark Energy Don’t Exist. New Theory Says the Universe Works Without Them
This could change everything we know about gravity and universal expansion.

Before the Hubble Space Telescope (HST), it was thought that the universe was slowing in its expansion and might someday fold back in on itself. In 1998, the HST revealed that rather than slowing, the rate of universal expansion is actually picking up. We still don’t know why.
One explanation is dark energy. Rather than allowing the universe to expand at a constant rate, dark energy pushes it along, causing it to pick up speed. Astronomers can only detect it indirectly, by measuring the distance between galaxies, for instance.
Dark energy is thought to comprise roughly 68% of the known universe, and dark matter 27%. Yet, we only know about them in terms of gravity. In other words, scientists can only detect them indirectly, by how they cause stars and galaxies to move and behave. For instance, the amount of matter inherent in galaxy clusters alone doesn’t account for the gravity that keeps them together. Some other force must be involved. Here, dark matter is the most common answer.
Astrophysicists have been postulating the existence of dark matter for about a century. Swiss astronomer Fritz Swicky was the first to see that there was far more matter in the universe than we could directly observe. Though he postulated this in 1933, US astronomer Vera Rubin made the concept more popular in the 1970s, when he used it to try and illustrate how stars move and at what velocity.
Australian and U.S. astrophysicists won the Nobel Prize in physics in 2011, for their 1998 discovery of the Hubble Constant. This is the rate at which the universe expands. Since then, despite many attempts to detect dark matter and dark energy, no progress has been made.
The Big Bang and the accelerated expansion of the universe. Credit: Coldcreation. Wikipedia Commons.
Now, André Maeder, honorary professor in the Department of Astronomy at the University of Geneva (UNIGE), has a radical theory that's shaking up astrophysics. He says neither dark matter nor dark energy exist. These concepts he believes are no longer required. The Swiss physicist can demonstrate how the universe works without them. His findings were published recently in a series of papers in The Astrophysical Journal. So how does this new model work?
It all surrounds what’s known as scale invariance. This is when the properties of something do not change no matter how you measure it, regardless of scale. We can multiply their energies or lengths by whatever number and they do not change. Certain fractals for instance, if we zoom in or fade back, remain the same size and shape. Their properties don’t change. The same is true of empty space. Whether you pan out or in, it's the same. This isn’t exactly foreign to physics. Scale invariance is actually a fundamental part of the theory of electromagnetism.
The Weiner process works on scale invariance, seen here. Credit: Cyp, Wikimedia Commons.
Maeder proposes that instead of dark matter or dark energy, we’ve simply forgotten to include scale invariance into the Standard Model—our current model of the universe. This has so far been developed mainly from Newton’s universal gravitation, Einstein’s general relativity, and quantum mechanics.
"In this model, there is a starting hypothesis that hasn't been taken into account, in my opinion," Maeder said. "By that, I mean the scale invariance of empty space; in other words, empty space and its properties do not change following a dilatation or contraction." If this is true, it would change everything we know about gravity and universal expansion.
What’s different is that Einstein believed empty spaced operated on what’s known as the cosmological constant. Today, we’d interpret it as a form of dark energy. Maeder’s model instead includes scale invariance in empty space. He tested his hypothesis on the accelerated expansion of space, and it worked without the need for dark energy. He also applied it to galaxy clusters. Their behavior was in line with Maeder’s calculations.
The Musket Ball Cluster. This controversial hypothesis can explain why star clusters stick together. Credit: Getty Images.
In another test, Maeder showed that he could account for why stars in the outer reaches of galaxies move faster than those within them. Dark matter is the usual explanation. Lastly, he accurately illustrated the dispersion of certain stars as they travel through the Milky Way, which until now has been difficult for astronomers to understand.
These findings are controversial. The Frankfurt Institute’s Sabine Hossenfelder, a physicist blogger, called Maeder’s hypothesis inconsistent. While astrophysicist Katie Mack of Australia’s University of Melbourne, said it’s been “massively overhyped.” There’s other evidence for dark matter she said, in the cosmic microwave background, the residue of the Big Bang. It’s also present in how galaxies are distributed. Finally, a phenomenon called gravitation lensing also hints at dark matter.
Though there are other ways to interpret Einstein, that doesn’t mean they’re true, Mack said. Until Maeder’s hypothesis is proven across a number of observations and measurements, his theory won’t supersede that which is already in place. But if he succeeds, it’ll be a paradigm shift in our entire understanding of how the universe operates.
For more on how the universe works from a more traditional view, click here:
A 62-year old Russian mystery (and conspiracy theory) has been solved
Some mysteries take generations to unfold.
Winter in the Ural Mountains
- In 1959, a group of nine Russian hikers was killed in an overnight incident in the Ural Mountains.
- Conspiracies about their deaths have flourished ever since, including alien invasion, an irate Yeti, and angry tribesmen.
- Researchers have finally confirmed that their deaths were due to a slab avalanche caused by intense winds.
In February 1959, a group of nine hikers crossed through Russia's Ural Mountains as part of a skiing expedition. The experienced trekkers, all employed at the Ural Polytechnical Institute, were led by Igor Dyatlov. On the evening of February 1, all nine appear to have fled their tents into the Arctic temperatures, for which they were unprepared. None survived.
Six of the members died of hypothermia; three suffered from physical trauma. Some members were missing body parts—a tongue here, a few eyes there, a pair of eyebrows for good measure. According to reports, no hiker appears to have struggled or panicked. They were likely too quickly overtaken by the hostile environment in Western Russia.
All the members were young, mostly in their early twenties; one member, Semyon Zolotaryov, was 38. Good health didn't matter. Given the uncertain circumstances—what made them flee into the bitter cold?—the incident known as Dyatlov Pass has long been the type of Area 51-conspiracy theory that some people love to speculate about. A vicious animal attack? Infrasound-induced panic? Was the Soviet military involved? Maybe it was the katabatic winds that did them in. Local tribesmen might not have liked the intrusion.
Or perhaps it was aliens. Or a Yeti. Have we talked about Yeti aliens yet?
These theories and more have been floated for decades.
a: Last picture of the Dyatlov group taken before sunset, while making a cut in the slope to install the tent. b: Broken tent covered with snow as it was found during the search 26 days after the event.
Photographs courtesy of the Dyatlov Memorial Foundation.
Finally, a new study, published in the Nature journal Communications Earth & Environment, has put the case to rest: it was a slab avalanche.
This theory isn't exactly new either. Researchers have long been skeptical about the avalanche notion, however, due to the grade of the hill. Slab avalanches don't need a steep slope to get started. Crown or flank fractures can quickly release as little as a few centimeters of earth (or snow) sliding down a hill (or mountain).
As researchers Johan Gaume (Switzerland's WSL Institute for Snow and Avalanche Research SLF) and Alexander Puzrin (Switzerland's Institute for Geotechnical Engineering) write, it was "a combination of irregular topography, a cut made in the slope to install the tent and the subsequent deposition of snow induced by strong katabatic winds contributed after a suitable time to the slab release, which caused severe non-fatal injuries, in agreement with the autopsy results."
Conspiracy theories abound when evidence is lacking. Twenty-six days after the incident, a team showed up to investigate. They didn't find any obvious sounds of an avalanche; the slope angle was below 30 degrees, ruling out (to them) the possibility of a landslide. Plus, the head injuries suffered were not typical of avalanche victims. Inject doubt and crazy theories will flourish.
Configuration of the Dyatlov tent installed on a flat surface after making a cut in the slope below a small shoulder. Snow deposition above the tent is due to wind transport of snow (with deposition flux Q).
Photo courtesy of Communications Earth & Environment.
Add to this Russian leadership's longstanding battle with (or against) the truth. In 2015 the Investigative Committee of the Russian Federation decided to reopen this case. Four years later the agency concluded it was indeed a snow avalanche—an assertion immediately challenged within the Russian Federation. The oppositional agency eventually agreed as well. The problem was neither really provided conclusive scientific evidence.
Gaume and Puzrin went to work. They provided four critical factors that confirmed the avalanche:
- The location of the tent under a shoulder in a locally steeper slope to protect them from the wind
- A buried weak snow layer parallel to the locally steeper terrain, which resulted in an upward-thinning snow slab
- The cut in the snow slab made by the group to install the tent
- Strong katabatic winds that led to progressive snow accumulation due to the local topography (shoulder above the tent) causing a delayed failure
Case closed? It appears so, though don't expect conspiracy theories to abate. Good research takes time—sometimes generations. We're constantly learning about our environment and then applying those lessons to the past. While we can't expect every skeptic to accept the findings, from the looks of this study, a 62-year-old case is now closed.
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Stay in touch with Derek on Twitter and Facebook. His most recent book is "Hero's Dose: The Case For Psychedelics in Ritual and Therapy."
Could muons point to new physics?
New data have set the particle physics community abuzz.
- The first question ever asked in Western philosophy, "What's the world made of?" continues to inspire high energy physicists.
- New experimental results probing the magnetic properties of the muon, a heavier cousin of the electron, seem to indicate that new particles of nature may exist, potentially shedding light on the mystery of dark matter.
- The results are a celebration of the human spirit and our insatiable curiosity to understand the world and our place in it.
If brute force doesn't work, then look into the peculiarities of nothingness. This may sound like a Zen koan, but it's actually the strategy that particle physicists are using to find physics beyond the Standard Model, the current registry of all known particles and their interactions. Instead of the usual colliding experiments that smash particles against one another, exciting new results indicate that new vistas into exotic kinds of matter may be glimpsed by carefully measuring the properties of the quantum vacuum. There's a lot to unpack here, so let's go piecemeal.
It is fitting that the first question asked in Western philosophy concerned the material composition of the world. Writing around 350 BCE, Aristotle credited Thales of Miletus (circa 600 BCE) with the honor of being the first Western philosopher when he asked the question, "What is the world made of?" What modern high energy physicists do, albeit with very different methodology and equipment, is to follow along the same philosophical tradition of trying to answer this question, assuming that there are indivisible bricks of matter called elementary particles.
Deficits in the Standard Model
Jumping thousands of years of spectacular discoveries, we now have a very neat understanding of the material composition of the world at the subatomic level: a total of 12 particles and the Higgs boson. The 12 particles of matter are divided into two groups, six leptons and six quarks. The six quarks comprise all particles that interact via the strong nuclear force, like protons and neutrons. The leptons include the familiar electron and its two heavier cousins, the muon and the tau. The muon is the star of the new experiments.
The Standard ModelCredit: Cush via Wikimedia Commons licensed under CC0 1.0
For all its glory, the Standard Model described above is incomplete. The goal of fundamental physics is to answer the most questions with the least number of assumptions. As it stands, the values of the masses of all particles are parameters that we measure in the laboratory, related to how strongly they interact with the Higgs. We don't know why some interact much stronger than others (and, as a consequence, have larger masses), why there is a prevalence of matter over antimatter, or why the universe seems to be dominated by dark matter — a kind of matter we know nothing about, apart from the fact that it's not part of the recipe included in the Standard Model. We know dark matter has mass since its gravitational effects are felt in familiar matter, the matter that makes up galaxies and stars. But we don't know what it is.
Whatever happens, new science will be learned.
Physicists had hoped that the powerful Large Hadron Collider in Switzerland would shed light on the nature of dark matter, but nothing has come up there or in many direct searches, where detectors were mounted to collect dark matter that presumably would rain down from the skies and hit particles of ordinary matter.
Could muons fill in the gaps?
Enter the muons. The hope that these particles can help solve the shortcomings of the Standard Model has two parts to it. The first is that every particle, like a muon, that has an electric charge can be pictured simplistically as a spinning sphere. Spinning spheres and disks of charge create a magnetic field perpendicular to the direction of the spin. Picture the muon as a tiny spinning top. If it's rotating counterclockwise, its magnetic field would point vertically up. (Grab a glass of water with your right hand and turn it counterclockwise. Your thumb will be pointing up, the direction of the magnetic field.) The spinning muons will be placed into a doughnut-shaped tunnel and forced to go around and around. The tunnel will have its own magnetic field that will interact with the tiny magnetic field of the muons. As the muons circle the doughnut, they will wobble about, just like spinning-tops wobble on the ground due to their interaction with Earth's gravity. The amount of wobbling depends on the magnetic properties of the muon which, in turn, depend on what's going on with the muon in space.
Credit: Fabrice Coffrini / Getty Images
This is where the second idea comes in, the quantum vacuum. In physics, there is no empty space. The so-called vacuum is actually a bubbling soup of particles that appear and disappear in fractions of a second. Everything fluctuates, as encapsulated in Heisenberg's Uncertainty Principle. Energy fluctuates too, what we call zero-point energy. Since energy and mass are interconvertible (E=mc2, remember?), these tiny fluctuations of energy can be momentarily converted into particles that pop out and back into the busy nothingness of the quantum vacuum. Every particle of matter is cloaked with these particles emerging from vacuum fluctuations. Thus, a muon is not only a muon, but a muon dressed with these extra fleeting bits of stuff. That being the case, these extra particles affect a muon's magnetic field, and thus, its wobbling properties.
About 20 years ago, physicists at the Brookhaven National Laboratory detected anomalies in the muon's magnetic properties, larger than what theory predicted. This would mean that the quantum vacuum produces particles not accounted for by the Standard Model: new physics! Fast forward to 2017, and the experiment, at four times higher sensitivity, was repeated at the Fermi National Laboratory, where yours truly was a postdoctoral fellow a while back. The first results of the Muon g-2 experiment were unveiled on 7-April-2021 and not only confirmed the existence of a magnetic moment anomaly but greatly amplified it.
To most people, the official results, published recently, don't seem so exciting: a "tension between theory and experiment of 4.2 standard deviations." The gold standard for a new discovery in particle physics is a 5-sigma variation, or one part in 3.5 million. (That is, running the experiment 3.5 million times and only observing the anomaly once.) However, that's enough for plenty of excitement in the particle physics community, given the remarkable precision of the experimental measurements.
A time for excitement?
Now, results must be reanalyzed very carefully to make sure that (1) there are no hidden experimental errors; and (2) the theoretical calculations are not off. There will be a frenzy of calculations and papers in the coming months, all trying to make sense of the results, both on the experimental and theoretical fronts. And this is exactly how it should be. Science is a community-based effort, and the work of many compete with and complete each other.
Whatever happens, new science will be learned, even if less exciting than new particles. Or maybe, new particles have been there all along, blipping in and out of existence from the quantum vacuum, waiting to be pulled out of this busy nothingness by our tenacious efforts to find out what the world is made of.
- Benjamin Franklin wrote essays on a whole range of subjects, but one of his finest was on how to be a nice, likable person.
- Franklin lists a whole series of common errors people make while in the company of others, like over-talking or storytelling.
- His simple recipe for being good company is to be genuinely interested in others and to accept them for who they are.
Think of the nicest person you know. The person who would fit into any group configuration, who no one can dislike, or who makes a room warmer and happier just by being there.
What makes them this way? Why are they so amiable, likeable, or good-natured? What is it, you think, that makes a person good company?
There are really only two things that make someone likable.
This is the kind of advice that comes from one of history's most famously good-natured thinkers: Benjamin Franklin. His essay "On Conversation" is full of practical, surprisingly modern tips about how to be a nice person.
Franklin begins by arguing that there are really only two things that make someone likable. First, they have to be genuinely interested in what others say. Second, they have to be willing "to overlook or excuse Foibles." In other words, being good company means listening to people and ignoring their faults. Being witty, well-read, intelligent, or incredibly handsome can all make a good impression, but they're nothing without these two simple rules.
The sort of person nobody likes
From here, Franklin goes on to give a list of the common errors people tend to make while in company. These are the things people do that makes us dislike them. We might even find, with a sinking feeling in our stomach, that we do some of these ourselves.
1) Talking too much and becoming a "chaos of noise and nonsense." These people invariably talk about themselves, but even if "they speak beautifully," it's still ultimately more a soliloquy than a real conversation. Franklin mentions how funny it can be to see these kinds of people come together. They "neither hear nor care what the other says; but both talk on at any rate, and never fail to part highly disgusted with each other."
2) Asking too many questions. Interrogators are those people who have an "impertinent Inquisitiveness… of ten thousand questions," and it can feel like you're caught between a psychoanalyst and a lawyer. In itself, this might not be a bad thing, but Franklin notes it's usually just from a sense of nosiness and gossip. The questions are only designed to "discover secrets…and expose the mistakes of others."
3) Storytelling. You know those people who always have a scripted story they tell at every single gathering? Utterly painful. They'll either be entirely oblivious to how little others care for their story, or they'll be aware and carry on regardless. Franklin notes, "Old Folks are most subject to this Error," which we might think is perhaps harsh, or comically honest, depending on our age.
4) Debating. Some people are always itching for a fight or debate. The "Wrangling and Disputing" types inevitably make everyone else feel like they need to watch what they say. If you give even the lightest or most modest opinion on something, "you throw them into Rage and Passion." For them, the conversation is a boxing fight, and words are punches to be thrown.
5) Misjudging. Ribbing or mocking someone should be a careful business. We must never mock "Misfortunes, Defects, or Deformities of any kind", and should always be 100% sure we won't upset anyone. If there's any doubt about how a "joke" will be taken, don't say it. Offense is easily taken and hard to forget.
Not following Benjamin Franklin's advice.Credit: Ronald Martinez via Getty Images
On practical philosophy
Franklin's essay is a trove of great advice, and this article only touches on the major themes. It really is worth your time to read it in its entirety. As you do, it's hard not to smile along or to think, "Yes! I've been in that situation." Though the world has changed dramatically in the 300 years since Franklin's essay, much is exactly the same. Basic etiquette doesn't change.
If there's only one thing to take away from Franklin's essay, it comes at the end, where he revises his simple recipe for being nice:
"Be ever ready to hear what others say… and do not censure others, nor expose their Failings, but kindly excuse or hide them"
So, all it takes to be good company is to listen and accept someone for who they are.
Philosophy doesn't always have to be about huge questions of truth, beauty, morality, art, or meaning. Sometimes it can teach us simply how to not be a jerk.
Our ancestors first developed humanlike brains 1.7 million years ago
A recent study analyzed the skulls of early Homo species to learn more about the evolution of primate brains.
