We May Be Moving Through The Universe Faster Than We Thought

Hello wonderful person, this is Anton, and today we're going to discuss some of the recent discoveries in regards to radio observations from across the universe. But specifically we're going to be diving into one of the most fundamental and most bizarre mysteries in cosmology that essentially centers around how fast we, our planet, our solar system, and even our galaxy, are actually moving through cosmos. The mystery that's been recently highlighted in one of the recent studies that used radio observations to discover something that nobody expected. There's a slight chance right now that we're actually moving through the universe way way faster than anyone imagined, and much faster than we should be moving. Which also sort of kind of contradicts some of the observations from the most mind-blowing map we've ever created, the cosmic microwave background. And so let's discuss some of these recent studies and what all of this means, but actually let's start with some of the previous discoveries and previous observations. And specifically with that CMB, the earliest light in the universe. Now based on many different observations over the years, we know that CMB provides a lot of information about the universe around us, and even about certain structures far away from us. But also CMB gives us a kind of a baseline for our speed based on what's known as the cosmic microwave dipole. But some of these most recent observations based on various radio sources super far away from us, potentially identified a very serious tension. Something they now refer to as radio dipole anomaly. And this is not just some kind of a little error, here this has 5.4 sigma discrepancy. In this case this means that it seems to be really there, and it has to be addressed in some of the future studies because right now it doesn't have an explanation. And that's basically what we're going to be discussing today. Trying to figure out what these observations mean, and trying to explore potential answers for this new bizarre mystery. But in order to understand what's really happening and why this is a mystery, let's actually talk about the observations and the measurements and how they're conducted. And so first we need to understand the baseline, the CMB dipole. The dipole that in simpler terms would look something like this. Now, what exactly are we looking at here? Well remember, CMB is the earliest light in the universe. It was released approximately 380,000 years after the Big Bang, when the hot plasma that the universe used to be made out of, finally turned into particles and allowed the light to travel through. And so as this light stretched and cooled for billions of years, it eventually turned very hot photons of about 3000 Kelvin into the photons that we observe today at approximately 2.725 Kelvin, that we refer to as the Cosmic Microwave Background. So basically this very faint microwave glow that comes from every single direction around us, and that represents the remnants of this early light. And here the uniformity of CMB is incredibly important because it essentially supports the cosmological principle. In scientific terms, this is referred to as homogenous and isotropic. But as we've discussed in previous videos, CMB is not perfectly uniform. It does have these tiny variations or anisotropies, which we believe were formed by some of the very early structures in the universe that created these slight temperature differences. For example, galactic clusters would make something appear just a little bit different, possibly making it appear just a little bit hotter, and likewise, galactic voids might make this light appear just a little bit colder. But here there's another variation that seems to be on a large scale. There's a slight temperature difference of 0.0035 Kelvin going from the west to the east, as you can see right here, with one side being slightly blueshifted and the opposite side being slightly redshifted. And, well, as you can imagine, this seems to be the result of motion. The motion of the solar system and the motion of the galaxy with respect to the so-called rest frame or cosmic frame that then creates this Doppler effect. And this motion has been calculated quite precisely and seems to be approximately 370 km per second. And so basically here we seem to be moving in a certain direction at 370 km per second. This has been established many years ago and seems to have been true up until relatively recently. Okay, now let's talk about the radio sky. This is obviously based on observations in slightly longer wavelengths and does show us very different features. And just to give you an example, here's the microwave radiation and here's the radio observations. Here what you're looking at is, of course, the Milky Way. But, crucially, it's important not to confuse the microwave dipole with the radio dipole, because technically they're measuring different things. And so the CMB dipole measures temperature, but the radio dipole is currently based on measurements of distant objects, specifically distant quasars, mostly focusing on their brightness. But here we have this very important question. If the universe truly follows the cosmological principle and it's the same everywhere, would the measurements from CMB also be reproducible using radio sources in the same way we can see it in the CMB? Or, just to rephrase this, does the CMB dipole align with the radio dipole? And if the cosmological principle is correct, the answer should be yes. The CMB dipole should be very similar to the radio dipole or should be at least somewhat correlated. But for radio sources, this can only be done by counting distant galaxies. This is known as the kinematic source count dipole. Okay, how does this work? It's essentially driven by two effects from motion, the Doppler shift and aberration. So when it comes to the Doppler shift, as we move toward a distant radio galaxy, the radio waves become blue-shifted, making the source appear just a little bit brighter. However, if we move away from something, the waves are red-shifted, making the object appear fainter. And so since the surveys only count sources above a certain brightness limit, we naturally count more bright sources in the direction we're moving and fewer sources in the opposite direction. So basically we should be seeing more galaxies toward one side of the dipole and less galaxies on the other side. And when it comes to aberration, this effect is supposed to shift the apparent position of some sources toward the direction of our motion. And so together these physical effects suggest that we can count radio galaxies and we should see slightly more of them in the direction we're headed toward, here we're talking about the constellation of Centaurus, and fewer in the opposite direction. But crucially, the size or the amplitude of this measurement has to match the observations from the CMB. But some of the previous surveys, especially surveys using infrared telescopes, sometimes found a bit of a problem. There was a bit of an inconsistency with the expected size of the dipole, and it was not matching the CMB dipole that's been studied rigorously for many years. And this new study, in 2025, seems to report this again, but this time using additional observations and independent calculations. So let's discuss this very recent 2025 analysis, which combines data from three massive wide-area radio surveys, referred to as LOTS-DR2, REXLO, and NVSS. But here researchers had to address one major complication. Many radio sources are actually made up of multiple components, which previous studies could not resolve and which often resulted in less accuracy. And so traditionally in some of the previous studies, some of these multi-component sources led to overdispersion, or basically a lot of additional errors. To fix this, this team developed a new statistical estimator. With this new mathematical method, increasing the measurements dramatically and making the results much more realistic, accounting for previous mistakes. And while surprisingly, this combined measurement once again discovered that the radio sources do not match the CMB. And specifically, the radio source count dramatically exceeded the expected value by a factor of 3.7, which translates to approximately 5.4 sigma when it comes to statistical analysis. Or to, I guess, rephrase this, this is extremely unlikely to be a random probability fluke. And right now the observations strongly suggest that the solar system, and of course our galaxy, seem to be moving across the universe 3.7 times faster than the current cosmological predictions based on the cosmic microwave background. And that means that we might be moving at approximately 1370 km per second instead of 370. But interestingly, even though the amplitude is wildly different, the overall direction for radio dipole is more or less the same. The overall angular separation is less than 5 degrees and could just be due to uncertainty. So the overall direction is consistent and matches previous observations. But there's a really important side note here. Right now this is still somewhat preliminary. As a matter of fact, some of the studies, especially studies using other telescopes such as Meerkat and the Meerkat absorption line survey, seem to have found results that do align with the CMB expectations and sort of contradict the study. Which potentially suggests that there is a problem with some of these surveys or that the way that these wide area surveys are designed and conducted may actually produce some kind of a discrepancy. In other words, this might be a measurement issue and not a universe issue. And so there might be some kind of a systematic error or some kind of a bias, because radio astronomy is notoriously challenging to precisely calibrate across wide fields, and occasionally leads to these systematic errors, especially the ones that operate at different radio frequencies. But here it's unlikely to be a systematic error across multiple surveys, because the results also seem to mimic previous observations using infrared quasars and infrared surveys as well. There, there was also this bizarre dipole detection that's difficult to explain. So the anomaly could be real after all. And that means that the question is, why? Why is there such a massive discrepancy between microwave dipole and radio dipole that seems to be 3.7 times larger? Well, if this is confirmed, this is definitely going to be a major challenge for the cosmological standard model. But we do have some potential explanations. Now, one explanation that nobody wants to deal with is, well, maybe the cosmological model is incorrect. Maybe the universe is not isotropic and is actually different in different directions, and thus changes property over distance. But a much more likely explanation, and the one that scientists are leaning toward, is what's known as the local bulk flow. The excess of motion in this case could be caused by a very large-scale motion of matter, that could be the result of some kind of a major structure such as the cosmic web and our position in it. Or basically, our local cosmic neighborhood might be moving much faster than expected, because we're just located in this river of galaxies, and are just headed in a certain direction. This would actually not violate any principles, and thus align with a lot of modern observations and modern propositions. I would also suggest that we're basically inside this very difficult-to-detect river, that needs to be studied more in order for us to understand the universe itself. If you actually want to learn more about the cosmic web, check out some of the previous videos in the description. And so in short, we have no idea what's happening, but something seems to be happening. There seems to be a bit of a discrepancy between observations in the radio light compared to the cosmic microwave background, and additional deviations in the infrared. And though both observations confirm that we're moving toward the constellation of Centaurus, which is by the way where the famous Great Attractor is located, here the observations in radio light and the microwave light give us very different velocity. And so we're left with two conflicting fundamental measurements. The cosmic microwave background that's been used to define the universal rest frame tells us we're moving at 370 km per second, but observations of distant radio sources suggest we're moving at almost 1400 km per second. And currently that makes no sense. So essentially this reminds us that there's still so much more to discover, and we still don't really understand our place in the cosmos. But the solution to this mystery will most likely rely on some of the future surveys, including an upcoming Large Area Sky Survey known as LOTSS-DR3. And eventually surveys conducted by super large telescopes such as the Square Kilometer Array. This will definitely provide us with more accurate data, and potentially help us pinpoint the origin of this excess radio dipole. And so whether the universe is fundamentally different and not isotropic, or we're just moving through some kind of a giant cosmic current inside the cosmic web, only time will tell. For now, the questions remain open. And that means we'll come back and discuss them more in some of the future videos. Thank you for watching, subscribe, come back tomorrow to learn something else, support the channel on Patreon where you can find additional videos, videos without any ads and can be DMed directly, or by joining the channel membership that grants you early access. You can also buy the Wonderful Person t-shirt in the description below. Stay wonderful, I'll see you tomorrow, and as always, bye bye.