Enter the Antiverse
Jax Gottschalch '25
With the assistance of Dr. Keith Voss, Mr. Miguel Bayona, and various friends as sounding boards.
Enter the Antiverse
0 1 1 2 3 5 Humans love patterns. 8 13 21 Identifying a common thread helps us find order in chaos and meaning in the arbitrary. But when something does not follow the pattern, 35…yuck! Perhaps the simplest form of pattern is symmetry: the 1:1, the ambigram, the palindrome. We love symmetry. You can see it when you gaze at the windows on a suburban house or the wheels on your best friend's new Tesla; the stairs penetrating the Lawrenceville School Bowl walls and the pathway connecting them. Our obsession with symmetry does not end with us though. Nature too adores symmetry. Split a human vertically and mirror one half. It will be nearly identical. In fact, the adoration of symmetry is not limited to Earth. Symmetry is so important that it is baked into the very fabric of the universe. There are many fundamental symmetries to the universe, some simple and some complex. They include temporal, translational, and gauge symmetries. When these symmetries are followed, as is typical, we call them preserved. But when one is disobeyed, we call it symmetry breaking. The universe, much like us, does not approve of this patternless state, and chaos ensues. Take for example the breaking of the SU(2) X U(1) gauge symmetry; the breaking of this symmetry is directly responsible for giving particles mass. Hence symmetry breaking does not always have negative consequences, but it is uncommon. With an increase in vacuum energy, the earlier symmetry could be restored. I don’t think I need to explain what would follow if that happens.Therefore the universe likes to keep its symmetries. This is why it is strange that in the current cosmological model, three of the most basic symmetries (together known as CPT symmetry) are broken. Charge symmetry (C) is a symmetry on the atomic scale in which if you reverse the charges of the interacting particles, the result will stay the same. Negative and Negative repel, Positive and Positive repel. Parity symmetry (P) is best thought of as mirror symmetry and has to do with the spin of subatomic particles. Finally, there is Time (T) symmetry: if you are running through the house and knock over a lamp, then rewind time to before you knocked over the lamp, all the same events happened, just in reverse. To physicists, CPT symmetry is as normal as Saturday classes are to boarding school students. Yet these very simple symmetries are broken just a few milliseconds into the universe’s life in a period known as the Inflationary Epoch. In this time, the universe rapidly expanded before slowing down again to cruising speed. Cosmic Inflation is analogous to the ball of a ballpoint pen rapidly expanding to the size of the earth in a second. Such a tremendous positive force should have left ripples in spacetime (known as gravitational waves), yet none have yet been observed. These peculiarities led a group of physicists to a model which nixes the Inflationary Epoch and maintains CPT symmetry. The implications of their research are startling.
Let’s rewind. There is a reason the Inflationary Epoch is the preferred cosmological model: it matches observations. In order for this new CPT symmetry preserving model to be considered, it too must match observations, which it does. Through applications of perturbation theory, a CPT symmetry preserving universe cancels out primordial vorticity (spinning) and creates the same boundary conditions that make the inflationary theory favored. One of the most amazing aspects of these results is a subtle one. As time increases, so do the density perturbations, which has the effect of creating a thermodynamic arrow of time. Thus, entropy!
Even cooler, CPT symmetry actually preserves linear perturbation theory. Without the symmetry, the calculations would not be possible, so the theory sustains itself in a mathematical elegance difficult to portray in words. Now that it has been established that this new model is at least on par with the current, the time is ripe to explore its incredible implications. First, it predicts new subatomic particles. To those who are physics savvy, this may not seem a great accomplishment. New discoveries were so common that Willis Lamb suggested that those who discovered new particles should be fined, and Enrico Fermi remarked that he would have to be a botanist to remember all their names.
However, these were written in the mid-20th century. Since then, there has been a lull in new elementary particle discoveries, with only one of note (the Higgs Boson). With the building of the Large Hadron Collider at the European Council for Nuclear Research (CERN), scientists expected to find a myriad of new results such as supersymmetric and KK particles (which would prove supersymmetry and extra-dimensions respectively), yet came up empty-handed. It is one thing to predict a new particle (both supersymmetry and extra-dimensional theories do this quite well), but another entirely to actually find it.
There have been recent experimental results that may have identified the particles. More data must be collected for it to be conclusive, but so far the results of the ANITA experiments look very promising. The results are an especially exciting aspect of this paper in that it makes falsifiable claims. This means this theory can be proven correct or false. The theory claims that the particles are right-handed neutrinos and that the light ones are majorna. One is massless and the other two are thermodynamically coupled. Let me break it down. In the standard model, particles are divided into generations and handedness. Generations are by mass, and there are three. Handedness is the direction that a particle spins in a characteristic known as chirality. So far, there have been three neutrinos discovered, all massless: Electron Neutrino, Muon Neutrino, and Tau Neutrino in order of generations up. They are all left-handed. In a CPT symmetric universe, there are three new neutrinos, all right-handed and one massless (but the others are not, hence the light). They are all also majorna, or their own antiparticles, which is another testable aspect. Hopefully, in the future more research will determine if the observations from the ANITA experiments are evidence of the right-handed neutrinos predicted.
With luck, it is evidence, because there are a few more exciting aspects of these neutrinos that have me typing at the edge of my seat. For one, the two massless neutrinos neatly solve the riddle of matter-antimatter asymmetry, a problem that has puzzled physicists for decades. This is due to a process called thermal leptogenesis, where the extreme temperatures near the big bang cause a decay asymmetry in the two neutrinos. This may lead to a slightly higher amount of matter than antimatter. A few seconds later when the temperature drops, the decay becomes stable again, so the matter advantage does not grow any further and matches observations. This is an incredible result!
Yet it is still not the most amazing thing about right-handed neutrinos. Perhaps the greatest riddle in modern cosmology concerns dark matter. In order for the behavior of galaxies and galactic clusters to make sense, dark matter must exist. Yet despite this dark matter, we have not the slightest idea as to what it is. Until now. The right-handed neutrino is a perfect dark matter candidate. First and foremost, the particle has an extra Z2 symmetry νR1 → -νR1 which means that the particle is stable. More crucially, this symmetry prohibits the particle from interacting with any force except gravity. This prohibition explains why dark matter is so dark. This particle cannot be created by particle interactions if it does not interact. Instead, this model pulls another rabbit out of its hat. The right-handed neutrino (νR1) is created by gravity! This is as if by dropping your Big Red card it suddenly gained money (instead of going through the standard “interactions” to place money on it). More specifically, it derives from the inequality of the CPT-invariant universe and the “out” mode of the universe, which combined with gravity creates the particle. There are two modes of creationary and destructive operators, before the bang “in” and after “out”. Due to it not interacting with the “thermal bath” at the beginning of the universe, νR1 will have a lifetime longer than Hubble Time (the time from bang to now). This conclusion again matches experimental results. With a predicted mass of 4.8 × 108 GeV, the neutrino is heavy, stable, and accounts for observed dark matter results.
An equally if not more interesting result of this model is the creation of an antiverse. Frustratingly, the papers outlining the model by Boyle, Finn, and Turok are vague in regards to the universe-antiuniverse pair, instead focusing on the dark matter candidate. Yet the scarce details gleamed are frankly incredible. In the revised history created by this model, the universe does not start from a point of infinite density. Instead, it stems from a CPT invariant surface disingularized by Weyl transformations. That is to say instead of using a new theory to desingularize the big bang, symmetries are enforced. It is another example of a modern problem solved neatly within the model. This also matches the predictions of string theory, which requires the big-bang to be desingularized.
From this humble beginning sparks not one, but two universes (U1 and U2). U1is the universe we know and love, with our symmetries. U2is the universe before the bang, with time flowing backward and with flipped symmetries. The reversal of time is not as significant as it may appear. The illusion of time is created by a thermodynamic arrow stemming from the big-bang. It begins at low entropy, and will end in high entropy if current models are correct (the so-called heat death). The anti-universe similarly has a thermodynamic arrow pointing away from the bang, just in the opposite direction of ours. To them, it would appear our time is running backward and theirs forward. The bottom line, the symmetries will operate the same, just flipped (recall the magnet example: Positive and Positive repel, Negative and Negative repel).
This creates multiple questions: Is our universe the same as the anti-universe? Or is the anti-universe the inverse of ours? Perhaps it is completely different? In a discussion I had with Dr. Voss, he brought up the interesting point that symmetries are not always what they seem. He provided the example of energy symmetry on a halfpipe (neglecting friction). The ball rolls down one half, converting its Potential Energy into Kinetic and Rotational Energy. The transfer from Potential to Rotational results in the ball not going as far as it began on the other half. It will then roll down and reach the spot where it started. This whole ordeal traces an incomplete semi-circle. While this model does have some flaws, the point remains. Symmetries in the universe don’t always correlate to geometric symmetries.
Dr. Voss’ examples were admittedly focused on the macroscopic, classical realm of everyday life. However, the thought of asymmetrical symmetries inspired me to think a little deeper on the issue. Treating U1 and U2 as separate universes, it immediately becomes clear that they must be different, despite being governed by “the same” symmetries. This is due to a phenomenon known as quantum fluctuations, the spontaneous creation and dissipation of particles. The pops and poofs happen billions of times every second, and have no significant influence on the universe. This is true for most of cosmic history, except for the very beginning in a time known as the Planck epoch. Many interesting things happen at this time. At least three (but probably all) of the fundamental forces were united before spontaneous symmetry breaking occurred and separated them. Temperatures were so hot it is nearly unfathomable (10^32 Kelvin). Most importantly, modern physics breaks down, and quantum mechanics takes the driver’s seat. In areas so small, quantum mechanics becomes dominant over classical mechanics, and the quirks of the theory are in full swing. Quantum fluctuations have direct effects on other particles, shifting and shaping the universe in random bursts of quantum fun. It only takes one during this time for U2to be significantly different from U1 due to chaos theory. As the universe aged and cooled, the small change at the start expands to a huge change down the line. But it is nearly impossible to prove or disprove without an entire upheaval of physics.
There is currently an irreconcilable conflict between Quantum Mechanics (the physics of the small) and General Relativity (the physics of the big). The mathematics of general relativity requires a mostly flat background to work upon. This is true the majority of the time, except for in the Planck Epoch. Here, the quantum effects change the very fabric of reality into a chaos coined by the quantum foam. Herein lies the problem. The two most successful theories clash in the very area we need both to work properly. In order to do any calculations of very small and very hot areas (the main suspects are black holes, singularities, and the Planck Epoch), a theory reconciling these, a proper theory of quantum gravity, must be created. We have some decent attempts at this, String Theory and Loop Quantum Gravity are the forerunners, yet both suffer from crippling problems. Until this feud of theories is resolved, investigations into the earliest eras of U1 and U2 are mere speculation.
On a philosophical note, there is a definitive prediction within the model that is of great interest. Ultimately, the whole shebang began from nothing. One could attribute this to God, and I will not attempt to argue for or against this claim. Instead, I will focus on a second, alternate explanation. The universe must exist as a logical necessity. I first encountered this idea in a book titled “Why does the world exist” by Jim Holt. In the book, the author thoroughly examines every possibility and finds some quite interesting ones. Modal Ontological Arguments, A quantum free lunch, and sentient creators are all discussed. However the argument Jim Holt arrives upon is deeply infatuating and quite elegant. Let’s begin by establishing two philosophical pillars: Every truth has a reason and no truth is its own reason. Now imagine four categories reality can fall into: nothingness, every universe, the best universe, and then other generic possibilities. Now lest these realities fall prey to the principle of sufficient reason (the first pillar of the proof), they must have an explanation in the form of a selector. To explain nothingness is simplicity. The best universe by goodness. Every universe by fullness. The generic possibilities have no special selector. That is not to say that there is no selector, just that the selector is having no selector. Each of these selectors must also have a reason. At this point, some reality types are eliminated. The selector for goodness is goodness, but no truth can be its own reason, and thus circularity rules out the best universe. This follows for the other selectors as well, leaving only two meta-selectors. Simplicity and Fullness. Fullness does not select itself, but does select all realities. This cannot be so as only one reality can exist at a time and thus fullness does not work. All that is left is simplicity. Simplicity will select no selector in the second tier, and as this violates no philosophical tenets, is a valid meta selector. By process of elimination, simplicity must be the meta-selector the universe uses and thus there must be something rather than nothing.
This conclusion is truly an incredible result. So, at the most fundamental levels, the CPT model can make sense. The model accomplishes many great feat by providing a consistent alternative to the Inflationary Epoch, the matter-antimatter imbalance, and dark matter. It establishes numerous exciting avenues to pursue and tangifies ideas previously relegated to the realms of science fiction. Best of all, it is falsifiable and may be proven correct or incorrect in the near future. To send off this essay, I will return to philosophy one last time. Soren Kierkegaard remarked “Life can only be understood backwards, but it must be lived forwards”. It appears the universe truly took his message to heart.
References:
L. Boyle, K. Finn, and N. Turok, “The Big Bang, CPT, and neutrino dark matter,” 2018, doi: 10.48550/ARXIV.1803.08930.
L. Boyle, K. Finn, and N. Turok, “CPT-Symmetric Universe,” Phys. Rev. Lett., vol. 121, no. 25, p. 251301, Dec. 2018, doi: 10.1103/PhysRevLett.121.251301.
L. A. Anchordoqui, V. Barger, J. G. Learned, D. Marfatia, and T. J. Weiler, “Upgoing ANITA events as evidence of the CPT symmetric universe,” LHEP, vol. 1, no. 1, pp. 13–16, Mar. 2018, doi: 10.31526/LHEP.1.2018.03.